Search

Polybrominated diphenyl ethers (PBDEs) industrially used as flame retardants are nowadays considered emerging pollutants as they are endocrine disrupting chemicals (EDCs), persistent in the environment, bioaccumulative and in addition, its hydroxylated (OH-BDEs) and methoxylated (MeO-BDEs) metabolites have similar ecotoxic properties. The aim of this work was to develop an analytical method to be applied in the study of the bioconcentration and biotransformation of BDE-47 due to its bioavailability, toxicity and high persistence and abundance in environmental samples, including humans. So, a dependable ultrasonic extraction process followed to dispersive SPE clean-up step and GC-MS-μECD detection has worked out for the determination of BDE-47 and its main biotransformation products (MeO-BDEs and OH-BDEs), considering the polarity difference. In addition, an alternative method to bioconcentration official guideline OECD 305, developed previously with zebrafish (Danio rerio) eleutheroembryos (i.e., hatched but not yet free feeding embryos) is used, reducing dramatically the animal suffering but also time and reagents. Bioconcentration factors (BCF) were calculated using first order one-compartment toxicokinetic model. The profiles found show rapid absorption in the first hours of larval development and great bioaccumulative with capacity, finding bioconcentration factors (BCF) of 6631 and 44210 at nominal concentrations of 10 and 1 μg·L-1 (< 1% LC50), respectively. Metabolization studies show increasing concentrations of the metabolites BDE-28, 2'-OH-BDE-28 and 5-MeO-BDE-47 throughout the exposure time. The results obtained show the feasibility of the method for bioaccumulation and opens the possibility of metabolic studies with zebrafish eleutheroembryos, which is a very underdeveloped field without official testing or regulation.

The accumulation potency of zinc nanoparticles in Nile tilapia (Oreochromis niloticus) was previously studied but their impacts on proximate chemical composition in muscle tissue by describing the dose-dependent accumulation and the protective role of vitamins (E + C), have not been investigated. Therefore, this study was carried out to assess the protective role of vitamins (E + C) on Zn accumulation in muscle and gill tissues of O. niloticus exposed to three sub-lethal concentrations (1/8 LC50, 1/4 LC50, and 1/2 LC50) of zinc oxide nanoparticles (ZnO NPs) compared to zinc oxide bulk particles (ZnO BPs) as well as their effects on the induced chemical composition alterations for different experimental periods (7, 14, 21, and 28 days). The data displayed that fish exposed to the different sub-lethal concentrations of ZnO NPs or ZnO BPs have a significant increase (PO. niloticus fish.

The present research evaluated the phytoremediation potential of three selected plant species Tamarix. spp, Haloxylon. spp and Malcolmia Africana to remediate gold mine tailings in the center of Iran. To improve the ecological capability of the tailing dam and contaminated soil, two treatments of contaminated (tailing dam) and control (surrounding area of the gold mine) were chosen. The associated tailing and plants' shoot and root samples were collected and analyzed for total metal concentrations of Cobalt, Chromium, Strontium, Thorium, Titanium and Uranium. Translocation Factor (TF), BioAccumulation Coefficient (BAC) and Bioconcentration Factor (BCF) were estimated to assess the plant species potential for phytoremediation. Results indicated that Tamarix. spp showed the best growth on contaminated site (by height of 44.05 cm and weight of 105.3 mg) as compared to Haloxylon. spp and Malcolmia Africana. Metal accumulation rate was observed to be maximized in all three species; by 28.37%, 35.5% and 12.96% of Sr and 20.28%, 9.85% and 31.7% of Ti for Tamarix. Spp, Haloxylon. Spp and Malcolmia Africana, respectively. The study showed that Malcolmia Africana is the best accumulator of Strontium with TF, BAC and BCF of higher than one for both control and contaminated treatments. Also Tamarix. spp can translocate large amounts of Strontium, Thorium, Titanium and Uranium from roots to shoots as well as Strontium and Titanium for Haloxylon. spp.

The present study was conducted to reveal the concentrations and patterns of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in seven species of freshwater aquatic products ( procambarus clarkii, ctenopharyngodon idellus, parabramis pekinensis, hypophthalmichthys molitrix, cyprinus carpioio, aristichthys nobilis, carassius auratus ) collected from freshwater aquaculture farms around Changsha, China. And the OCPs and PCBs in the muscle tissue of the aquatic products were analyzed to assess the dietary intake risk. The mean concentrations of OCPs and PCBs varied between 6.38 - 15.90 and 3.18 - 5.12 ng g -1 wet weight, respectively. Heptachlor and δ-HCH are the main contaminants of OCPs in the tested aquatic products, which account for over 74% of the total OCPs. The PCB52 is the main contaminant of PCBs, which account for over 88% of the total PCBs. The bioaccumulation levels of OCPs and PCBs in the aquatic products depend upon the species of aquatic products. The ctenopharyngodon idellus has the highest contamination levels of OCPs while the hypophthalmichthys molitrix has the highest contamination levels of PCBs. The mean lipid content in the freshwater aquatic products varies from 6.08% to 19.8% (dry weight) and presents a significant correlation with the contents of OCPs and PCBs. The health risk of the freshwater aquatic products is assessed by the hazard ratios and hazard quotient, a carcinogenic risk is found for the consumption of freshwater aquatic products.

The establishment of non-native species can result in complex shifts in food-web structure and ecosystem function that alter the bioaccumulation, transfer, and biomagnification of contaminants. Hemimysis anomala (the bloody red shrimp), a mysid native to the Ponto-Caspian region that is now established throughout the Laurentian Great Lakes region (North America) and Europe, is characterized by high densities and a trophic ecology that may be consequential to mercury fluxes and bioaccumulation. We combined methylmercury (MeHg) and stable isotope (δ15N and δ13C) analyses of invertebrates from Seneca Lake (NY, USA) to test the hypotheses that mercury concentrations differ among (1) H. anomala and native or naturalized analogs due to food-web position and (2) stages of H. anomala due to ontogenetic diet shifts. The MeHg concentration and δ15N of H. anomala exceeded other littoral invertebrates (such as amphipods, dreissenid mussels, and zooplankton >153 μm) and were as high as the pelagic, native Mysis diluviana. These taxa-specific patterns indicate intensified biomagnification of MeHg is possible in nearshore and reef-spawning fish following the establishment of H. anomala, an energy-dense prey item for economically and ecologically important fish. Larger, adult H. anomala had higher MeHg concentrations and more enriched δ15N than juveniles, and H. anomala collected at a littoral site had higher MeHg than a canal site. These intraspecies contrasts are consistent with the shift toward zooplanktivory in adult H. anomala. As both putative prey for fish and competitors for shared zooplankton resources, H. anomala may impact fish in compounding ways.

We compared mercury bioaccumulation in triploid and diploid walleye (Sander vitreus) in Narraguinnep Reservoir, Colorado, USA, and made several hypotheses that sex- and ploidy-specific differences in the allocation of energy towards reproductive development would affect mercury bioaccumulation. We tested our hypotheses with linear regression and a bioenergetics model informed by field data. We found diploid walleye had 28%–31% higher mercury concentrations on average than triploids, but there were no differences between sexes of the same ploidy. Triploids of mature age exhibited minimal gonadal development when compared to diploids. After accounting for reproductive investment, the bioenergetics model accounted for most of the observed difference in average mercury concentration between ploidies for females. Conversely, the energetic cost of producing testes was low, and gonadal development could not explain observed patterns for males. Costs associated with elevated swimming activity and metabolism by diploid males relative to other groups could explain the difference but requires further investigation. The use of triploid fish in stocking programs could prove useful for reducing mercury in fish destined for human consumption.

This study analyzed the function of different glutathione S-transferase (GST) isoforms and detoxification metabolism responses in Manila clam, Ruditapes philippinarum, exposed to 4 kinds of polycyclic aromatic hydrocarbons (PAHs) single, and their mixtures for 15 days under laboratory conditions. 13 kinds of GSTs in R. philippinarum were classified, and the results of tissue distribution indicated that 12 kinds of GSTs (except GST sigma 3) expressed most in digestive glands. We detected the mRNA expression levels of aryl hydrocarbon receptor signaling pathway, and detoxification system in digestive glands of clams exposed to benzo[a]pyrene (BaP), chrysene (CHR), benzo[a]anthracene (BaA), benzo[b]fluoranthene (BbF), and BaP + CHR + BaA + BbF, respectively. Among these genes, we selected GST-sigma, GST-omega and GST-pi as potential indicators to BaP; GST-sigma, GST-A and GST-rho to CHR; GST-pi, GST-sigma, GST-A, GST-rho and GST-microsomal to BaA; GST-theta and GST-mu to BbF; while GST-pi and GST-mu to the mixture of BaP, CHR, BaA and BbF. Additionally, the bioaccumulation of PAHs in tissues increased remarkably over time, and showed an obvious dose-effect. Under the same concentration, the bioaccumulation in single exposure group was higher than that in mixture group, and the bioaccumulation of PAHs in tissues with different concentrations of stress was irregular. The results revealed the metabolic differences and bioaccumulation rules in clams exposed to four kinds of PAHs, and provided more valuable information for the PAHs risk assessment.

Sediments and water columns in the Los Angeles Outer Harbor, a major port behind a breakwater, contain DDTs and PCBs from a nearby superfund site and contaminants brought in by ships, boats, stormwater, a river and a wastewater outfall. White croaker, a bottom feeder, and queenfish, a water column feeder, are two bioindicators for this marine ecosystem whose conditions are assumed to be robust for this role at all times. The current study tests this benign assumption amidst progressively increasing DDTs/PCBs levels in their tissues. Results, as evident by progressively shrinking gonads, show a less than robust white croaker population particularly. While the males are generally larger than the female fish, the length (standard (SL) or total (TL)) and body mass (BM) of 80 white croakers collected over a period of eight years were found to be similar irrespective of gender (177 mm, 212 mm and 114 g, respectively). Queenfish (67) did not show such similarity over the same period (female: 152 mm SL, 177mm TL, 56 g BM; male: 145 mm SL, 172 mm TL, 50 g BM). The site-specific expressions/values capturing the current conditions of these fish are SL=0.835[TL]-1.68 (r 2 =0.914, n=68) and SL=0.891[TL]-8.88 (r 2 =0.961, n=50) for white croaker and queenfish, respectively. In the allometric growth equation BM=a[SL] b , a and b are 2.83×10-4 and 2.49 (r 2 =0.817) for white croakers, and 6.10×10-5 and 2.73 (r 2 =0.825) for queenfish, respectively. The relative coefficients of condition K n are 0.97±0.07 and 1.01±0.12 for white croakers and queenfish, respectively. Molecular level studies are needed to establish definitively the links between DDTs/PCBs bioaccumulation in fish tissues and the robustness of the fish populations. This article is protected by copyright. All rights reserved.

Heavy metal pollution in the aquatic ecosystem has been a problem globally, this is because of their ability to accumulate in aquatic organisms particularly in fish which is a source of diet for most humans. In the present study, the bioaccumulation of five heavy metals (Cd2+, As+5, Cr+6, Pb2+ and Hg2+) was determined in the water, sediments, and fishes (Clarias gariepinus, Bagrus bayad, and Oreochromis niloticus) using Microwave Plasma Atomic Emission Spectroscopy (MP-AES) and the potential human health risk for local consumers was evaluated using standard indices. The measured mean concentration level (mg/kg) of the metals in water and sediment from five sampling location in the reservoir were 0.64 ± 0.10, 0.56 ± 0.43, 0.39 ± 0.18, 0.51 ± 0.02, 0.31 ± 0.01 mg/L, and 1.76 ± 0.05, 1.68 ± 0.00, 2.46 ± 0.83, 1.99 ± 0.06 and 1.53 ± 0.61 mg/g for Cd2+, As+5, Hg2+, Pb2+ and Cr+6 respectively. The result of the heavy metal content in the fish depicts the highest toxicity of Arsenic in the flesh, gills, and liver as 5.04 mg/kg, 5.79 mg/kg, and 2.13 mg/kg respectively. Bioaccumulation factor (BAF) of the heavy metals in B. bayad and O. niloticus were higher than C. gariepinus. Potential human health risks related with the intake of these metals were evaluated in terms of Estimated Daily Intake (EDI), Target Hazard quotient (THQ) and hazard index (HI) assessed for repercussions suggest that the values were above the permissible limit for both adults and children as recommended by WHO/FAO. The result of this study shows the health risks associated with the consumption of heavy metals through the intake of the studied fishes, therefore, there is a need for a sustainable management approach and biomonitoring of these heavy metals in Cika Koshi reservoir. This will minimize pollution of the aquatic environment which is a health threat for human consuming fishes contaminated with heavy metals.

Developing an understanding of factors that influence the accumulation and magnification of heavy metals in fish of the Laurentian Great Lakes is central to managing ecosystem and human health. We measured muscle tissue concentrations of heavy metals in Lake Michigan prey fish that vary in habitat use, diet, and trophic position, including alewife, bloater, deepwater sculpin, round goby, rainbow smelt, and slimy sculpin. For each individual, we measured tissue concentrations of four metals (chromium [Cr], copper [Cu], manganese [Mn], and total mercury [THg]), stable isotope ratios for trophic position (δ15N and δ13C), and individual fish attributes (length, mass). Total mercury concentration was positively related to total length and δ15N. Of all species, round goby had among the greatest increases in mercury per unit growth and was most isotopically distinct from other species. Profundal species (bloater, deepwater sculpin, slimy sculpin) had similar high THg tissue concentrations, possibly due to slower growth due to cold temperatures, whereas other species (alewife, round goby, rainbow smelt) showed more variation in THg. In contrast, other metals (Cr, Cu, Mn) had either a negative or no relationship to total length and δ15N, suggesting no bioaccumulation or biomagnification. Potential incorporation of mercury by sportfish may thus be related to species, age, diet, trophic position, and habitat of prey fish. Our findings serve as a foundation for understanding how heavy metals accumulate in Lake Michigan food webs and highlight the continued need for management of metal input and cycling in Lake Michigan.

Metal pollution is one of the main environmental threats in freshwater ecosystems. Aquatic animals can accumulate these substances and transfer them across the food web, posing risks for both predators and humans. Accumulation patterns strongly vary depending on the location, species, and size (which in fish and crayfish is related to age) of individuals. Moreover, high metal concentrations can negatively affect animals’ health. To assess the intraspecific relationship between metal accumulation and size and health (proxied by the body condition) of individuals, the concentration of 14 metals (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Pb, Se, Zn) was analyzed in six alien species from the highly anthropogenically altered Arno River (Central Italy): five fish (Alburnus alburnus, Pseudorasbora parva, Lepomis gibbosus, Ictalurus punctatus, and Silurus glanis) and one crayfish (Procambarus clarkii). We found that in P. clarkii, Cu was negatively related to size, as well as Al in L. gibbosus and Mg for adult I. punctatus. Positive size-dependent relationships were found for Hg in L. gibbosus, Fe in S. glanis, and Cr in juvenile I. punctatus. Only Co and Mg in S. glanis were found to negatively correlate with individual health. Since metal concentrations in animal tissue depend on trade-offs between uptake and excretion, the few significant results suggest different types of trade-offs across different species and age classes. However, only predatory fish species (L. gibbosus, I. punctatus, and S. glanis) presented significant relationships, suggesting that feeding habits are one of the primary drivers of metal accumulation.

The exponential rise in the Nigerian population has necessitated the use of agrochemicals for enhanced agricultural yields to meet the ever-rising demand for food. However, agrochemicals such as organochlorine pesticides (OCPs) have caused several devastating health and ecological challenges. The study was therefore aimed at assessing the bioaccumulation of OCPs and the associated parasitological and microbial susceptibility in P. obscura to determine the possible ecological impacts of the chemical. A total of 106 specimens of Parachanna obscura fish species were sampled between July and November 2019 from Lekki Lagoon in Lagos, Nigeria. Four culture media, namely nutrient agar (NA), MacConkay agar (MCA), eosin methylene blue (EMB), and sabouraud dextrose agar (SDA) were employed in microbial culture. These microbes were subjected to ceftazidime, ceftriaxone, cefuroxime, gentamicin, ofloxacin, augmentin, nitrofurantoin, ciprofloxacin, and erythromycin to test for resistance, susceptibility and intermediate statuses before and after curing. OCPs were tested in the water, sediment, and tissues of P. obscura using gas chromatography flame ionization detector (GC-FID). P. obscura sampled in the lagoon had poor growth exponent which was characterized by negative allometry (slenderness) in the sampled fish. Although the incidence of parasitic infection in the fish was not alarming, the situation might be aggravated if the prevalent anthropogenic activities persist, resulting in immunosuppression. Regulation of anthropogenic activities in the catchment area is recommended to forestall the prognosis of health and environmental hazards associated with the agricultural, industrial, pharmaceutical, and municipal activities around the lagoon. Bacteria that conferred the most resistance to the majority of the antibiotics were Staphylococcus sp., Micrococcus sp. Escherichia coli and Klebsiella sp., testing positive to plasmid profile. They conferred high resistance to the antibiotics before plasmid curing but became highly susceptible post- plasmid curing. This implies that the gene for resistance in the bacteria isolates was plasmid-mediated, that is, they were obtained from the environment. In the event of an outbreak of waterborne diseases such as cholera, typhoid, dysentery, and diarrhea, there may be non-response to treatment among the infected inhabitants. The incidence of antibiotic resistance in bacteria colonies recorded in this study is of great public health concern, given the possibility of the antibiotic-resistant bacteria strains being passed to humans through fish consumption, resulting in increased multi-drug resistance in humans. Regulation of anthropogenic activities around the lagoon is recommended to forestall prognosis of health and environmental hazards associated with OCPs from agricultural, industrial, pharmaceutical, and municipal sources. Resumo O aumento exponencial da população nigeriana exigiu o uso de agroquímicos para aumentar a produção agrícola e, assim, atender à crescente demanda por alimentos. No entanto, agroquímicos como pesticidas organoclorados (OCPs) causaram vários problemas de saúde e ecológicos. Portanto, o estudo teve como objetivo avaliar a bioacumulação de OCPs e a suscetibilidade parasitológica e microbiana associada em Parachanna obscura, a fim de determinar os possíveis impactos ecológicos desse produto químico. Foi amostrado um total de 106 espécimes de P. obscura entre julho e novembro de 2019 da lagoa Lekki, em Lagos, Nigéria. Quatro meios de cultura, como o ágar nutritivo (NA), o ágar MacConkay (MCA), o ágar eosina azul de metileno (EMB) e o ágar sabouraud dextrose (SDA), foram empregados na cultura microbiana. Esses micróbios foram submetidos a ceftazidima, ceftriaxona, cefuroxima, gentamicina, ofloxacina, augmentin, nitrofurantoína, ciprofloxacina e eritromicina para testar resistência, suscetibilidade e status intermediário antes e depois da cura. Os OCPs foram testados na água, sedimentos e tecidos de P. obscura usando um detector de ionização de chama por cromatografia em fase gasosa (GC-FID). Os peixes amostrados de P. obscura da lagoa apresentaram um expoente de crescimento ruim, caracterizado por alometria negativa (esbelteza). Embora a incidência de infecção parasitária nos peixes não tenha sido alarmante, a situação pode ser agravada se as atividades antropogênicas prevalecentes persistirem, resultando em imunossupressão. Recomenda-se a regulamentação de atividades antropogênicas na área de captação para prevenir o prognóstico de riscos à saúde e ecológicos associados a atividades agrícolas, industriais, farmacêuticas e municipais ao redor da lagoa. As bactérias que conferiram maior resistência à maioria dos antibióticos foram Staphylococcus sp., Micrococcus sp., Escherichia coli e Klebsiella sp., com teste positivo para o perfil plasmidial. Elas conferiram alta resistência aos antibióticos antes da cura do plasmídeo, mas se tornaram altamente suscetíveis após a cura dele. Isso implica que o gene de resistência nos isolados de bactérias foi mediado por plasmídeo, ou seja, foi obtido do ambiente. No caso de surtos de doenças transmitidas pela água, como cólera, febre tifoide, disenteria e diarreia, pode haver não resposta ao tratamento entre os habitantes infectados. A incidência de resistência a antibióticos nas colônias de bactérias registradas neste estudo é de grande preocupação para a saúde pública, dada a possibilidade de que as cepas de bactérias resistentes a antibióticos sejam transmitidas aos seres humanos por meio do consumo de peixes, resultando em maior resistência a múltiplas drogas em seres humanos. Recomenda-se a regulamentação de atividades antropogênicas ao redor da lagoa para impedir o prognóstico de riscos à saúde e ecológicos associados aos OCPs de fontes agrícolas, industriais, farmacêuticas e municipais.

We assessed fiddler crabs' (Minuca burgersi) ability to secrete metallic contaminants through ecdysis under controlled conditions. We fed them with contaminated food with different copper (Cu) and lead (Pb) amounts and measured their concentration in the released and renewed exuviae. We found a significant reduction in the average concentrations of Cu and Pb in the released and renewed exuviae-eliminating the exoskeleton in the ecdysis process helps in the metal detoxification mechanism of these animals. A portion of the concentration of metals is retained in the crustaceans' exuvia, and thus, they can be used to analyze bioaccumulation in ecosystems. Our results also reinforce the need for attention to the contamination characterization in crustaceans before and after ecdysis to avoid underestimation effects.

Contaminant substances consist of chemical elements that present the potential to adversely impact the ecology of the environment, thus representing a threat to local fauna and flora. In this context, heavy metals are critical agents that, depending on the nature and level, are potentially toxic to living organisms. In order to evaluate the bioaccumulation of heavy metals in the Santos estuary and to determine the potential influence of salinity gradient on the heavy metal bioconcentration, the present study measured the concentrations of As, Cd, Pb, Cu, Cr, Fe, Ni, and Zn in two bivalve species (Crassostrea rhizophorae and Perna Perna) sampled at different sites of Santos Bay, in the southeastern region of Brazil. Throughout the study, the "sentinel species" used were effective in bioaccumulating contaminants. In oysters, based on the Brazilian legislation, critical limits were exceeded for As, Zn, Cu, and Cr. In the case of mussels, on the other hand, only for As, Zn, and Cr, the critical limits were overcome. In the present study, obtained data suggested salinity as a determinant parameter in As incorporation processes of bivalve mollusks. PRACTITIONER POINTS: The present study presents important results for the development of environmental management policies in estuarine environments. The present study points out differences between different organisms as biomonitors, providing subsidies for the decision of an effective biomonitoring program. The present study discusses values of contaminants as a danger to public health in Santos Bay, which can be extrapolated to other similar environments around the world.

The study showed novel findings about changes in the fate and bioavailability of conazole fungicides (CFs) after biochar (BC) addition to soil. Two contrasting soils (low- and high-sorbing of CF; L soils, H soils) were amended by three BCs (low-, moderate-, and high-sorbing of CF; L-BC, M-BC, H-BC) at 0.2% and 2% doses. Epoxiconazole (EPC) and tebuconazole (TBC) were then added to the soil–BC mixtures, and their degradation, bioaccumulation in earthworms (Eisenia andrei), and bioconcentration in lettuce (Lactuca sativa) were studied for three months. Also, stir bar sorptive extraction (SBSE) was performed to determine CF (bio)accessibility. The EPC and TBC degradation in the soil–BC mixtures followed usually the first-order decay kinetics. The BC addition prevalently decreased the pesticides degradation in the L soil mixtures but often increased it in the H soil mixtures. In general, EPC degraded less than TBC. BC type and dose roles in the pesticides degradation were unclear. The BC addition significantly reduced pesticide uptake to the earthworms in the L soil mixtures (by 37–96%) and in the H soil mixtures (by 6–89%) with 2% BC. The BC addition reduced pesticide uptake to the lettuce roots and leaves significantly—up to two orders of magnitude, and this reduction was strong in H soil mixtures at 2% of BC. The BC addition reduced the CF (bio)accessibility measured by SBSE in all L soil mixtures and some H soil mixtures with 2% BC. Although not significant, it also seems that the pesticide bioaccumulation, bioconcentration, and (bio)accessibility were decreasing according to the BC type (L-BC > M-BC > H-BC). The pesticide concentrations in the earthworms and lettuce correlated significantly to the SBSE results, which indicates this technique as a possible predictor of biotic uptake. Our results showed that the interactions were hard to predict in the complex soil–BC–pesticide system.

The metals present in freshwater have a toxic profile with bioaccumulation and are biomagnified along the aquatic food chain. The metals induce high sensitivity in most aquatic organisms, while others, such as some microalgae species, evolve towards resistance. Therefore, this research predicted through the Combination Index method the binary interaction exposed to divalent metals by inhibiting population growth in a Cd-resistant strain (DcRCd100) compared to the wild-type strain (Dc1Mwt) of Dictyosphaerium chlorelloides and evaluate the specific resistance level obtained by DcRCd100 to Cd relative to other divalent metals.The results showed that DcRCd100 presents resistance compared to Dc1Mwt in individual exposure in the order of Fe2+ > Ni2+ > Cd2+ > Co2+ > Zn2+ > Cu2+ > Hg2+ with 50% inhibitory concentration at 72 h of exposure (IC50(72)) values 1253, 644.4, 423, 162.7, 141.3, 35.1, and 9.9 µM, respectively. It induces cross-resistance with high antagonistic rates (Combination Index (CI); CI > > 1) in the Cd/Zn and Cd/Cu. Cd/Ni, its initial response, is antagonistic, and it ends in an additive (CI = 1). DcRCd100 showed a lower resistance in Co, and Cd/Fe resistance was reduced individually. The interaction with Hg increased its resistance ten times more than individually.This research highlights the use of the CI as a highly efficient prediction method of the binary metal interactions in wild-type and Cd-resistant strains of D. chlorelloides. It may have the potential for metal accumulation, allowing the development of new methods of bioremediation of metals in effluents, and to monitor the concentration of metals in wastewater, its relative availability, transport, and mechanisms on resistant strains of microalgae.

Hydrocarbons and heavy metals (HM) present in automobile wastes get into water bodies close to automobile mechanic villages. They deteriorate the physico-chemical qualities of such water bodies and exert toxic effects on fish and other aquatic fauna. They also pose risks to humans that consume fish from streams near such automechanic villages. There is paucity of information on the HM contents of Agba stream, Ilorin and no information on the bioaccumulation of HM in the tissues of Pellonula afzeliusi is currently available. The purpose of this study was to assess the physico-chemical qualities of water and bioaccumulation of HM in the tissues of Pellonula afzeliusi fish collected from Agba stream, Ilorin, Kwara State, Nigeria. Water and samples of Pellonula afzeliusi were collected from the upstream (station A), midstream (station B) of Agba stream located close to an auto-mechanic village and Oyun dam (control site, station C) located within the University of Ilorin. Standard methods were used to analyse oil and grease (OG), total petroleum hydrocarbon (TPH) and HM in water samples. The concentrations of TPH and HM were analysed in the skin, bone, muscle, gills, gastrointestinal tract, liver and kidney of the fish. The order of water HM concentrations indicated Zn > Cd > Ba> Fe > Pb at station A; Cd > Zn > Fe > Ba > Pb at station B, and Zn > Ba > Pb > Fe >Cd at station C. TPH and HM bioaccumulated in the tissues of fish while lead was not detected in all tissues from station C. Bioaccumulation factor varied with the highest values t station C. The result of this study indicated heavy pollution burden in station B with lower pollution burden in station C (the control site). These call for attention of government in ensuring ecological restoration and prevention of further discharge of automobile wastes into the stream. Keywords: Automobile wastes, Heavy metals, Hydrocarbons, Bioaccumulation, Pellonula afzeliusi

Persistent organic pollutants (POPs) in biota are influenced by ecological, physiological, and physicochemical properties; however, there is a need for a better understanding about the interplay of these parameters on POP dynamics and fate. To address this, POPs in three Lake Erie freshwater fishes (freshwater drum, Aplodinotus grunniens; walleye, Sander vitreus; and white perch, Morone americana) with different feeding ecologies were assessed using life history characteristics and three stable isotopes (δ13 C, δ15 N, and δ34 S). Lipid normalized POP concentrations were in the range of past studies and were generally similar among the three species when all ages were combined. Principal component analysis (PCA) found the two significant PCs (explaining 59% and 10% of the variation), with all POPs loading significantly onto PC1, which indicated a common source of contamination, likely legacy sediment loads. Loadings on both PCs were correlated with POP log KOW . Age, habitat use (δ13 C and δ34 S), trophic position (δ15 N) and interactions between age and δ15 N, age and species, and δ15 N and δ34 S were significant predictors of POP concentration based on PC1 scores, whereas δ13 C and species were significant predictors of PC2 scores. The similar concentrations among the species, yet variation related to the ecology (age and trophic position) across individuals demonstrates the complexity of contaminant dynamics in freshwater fish in a large lake system and the need to consider variation across individuals within species. Environ Toxicol Chem 2021;40:3421-3433. © 2021 SETAC.

The study vigilantly considered the load of Pb, Cd, Cr, Cu, and Zn in a variety of tissues (muscle, gills, and liver) of 5 fish species (Mystus gulio, Notopterus notopterus, Notopterus chitala, Mugil cephalus, and Glossogobius giuris) collected from six sites in the lower Gangetic area. The study showed the lowest concentration of metals in the muscles. The accumulated patterns of heavy metals differed in different regions and concentrations fluctuated between the liver and gills. The target hazard quotient (THQ) value has been measured in contaminated fish. The THQ values for all the metals in respective fishes are below 1 that indicate that indirect intake of metals by consuming these selected fishes will not result in potential health hazard in human. The estimated daily intake (EDI) results were also calculated. EDI levels of all elements are lower than the permissible limit indicating a lower chance for health risk to occur. However, doses below the recommended levels do not indicate that they are completely safe for consumption or those above are not to be used. Thus, it can be demonstrated that occurrence of Cd, Cr, Pb, Cu, and Zn in the preferred tissues of the selected fish species in the present study may not pretense severe human health risk after consumption at its existing concentration.

Aquatic organisms that inhabit coastal areas are often exposed to several contaminants. It is known that the bioaccumulation of contaminants can be amplified according to the species feeding habits and contaminant properties. As a consequence, species can experience different effects to contaminant exposure even if they inhabit the same area. The present study aimed to investigate the activities of carbonic anhydrase (CA), Ca2+-ATPase, and Mg2+-ATPase in different tissues (soft tissue, mantle, and gill) of three mollusk species (Lottia subrugosa, Stramonita brasiliensis, and Crassostrea brasiliana) with different feeding habits (herbivore, carnivore, and filter-feeder, respectively) which were sampled within a known contamination gradient at Santos Estuarine System (Southeastern Brazil). From the three enzymes tested, only CA was affected by the presence of contaminants within the contamination gradient evaluated. In general, the CA activity from the three species were lower in contaminated sites when compared to the reference site. The contrasting CA activity response observed in S. brasiliensis compared to L. subrugosa and C. brasiliana could be related to the tissue-specificity of this enzyme activity and species feeding habits (filter-feeders can accumulate more contaminants than herbivores and even carnivores). Results indicated that C. brasiliana mantle is the most suitable tissue for the use of CA analysis as a biomarker.

An investigative biomonitoring study was conducted along the coastal area of Laizhou Bay (China) to evaluate the impact of organic pollution on the clam Ruditapes philippinarum using bioaccumulation and multi-biomarker measurements. In addition, the polychlorinated biphenyls (PCBs), total petroleum hydrocarbons (TPHs) and nonylphenol (NP) content in surface sediment at the study sites were also analyzed. Concentrations of PCBs, TPHs and NP in the sediments of the study area were 1.90 ± 0.10 μg kg−1, 39.55 ± 2.42 mg kg−1, 9.23 ± 0.41 μg kg−1 dry weight, respectively, while the organic contaminants in the soft tissues of R. philippinarum were 14.81 ± 0.96 μg kg−1 for PCBs, 165.87 ± 5.03 mg kg−1 for TPHs and 86.16 ± 5.29 μg kg−1 for NP. Linear regression analysis on the levels of organic pollutants accumulated in R. philippinarum and in sediments showed no significant correlation. Multi-biomarkers including superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, total glutathione and lipid peroxidation were assayed in gills and digestive glands of R. philippinarum. Finally, the biomarkers in gills were selected to calculate the Integrated Biomarker Response (IBR) index and to evaluate the impact of the three organic contaminants on R. philippinarum collected from different sites. According to IBR results, the western coast and eastern coast exhibited higher environmental stress than the sampling sites along the southern coast of Laizhou Bay. Significant correlation was found between the level of organic contaminants in the sediments and IBR whereas no dependence was found between pollutants’ concentrations in sediments and separate biomarker responses. The results showed that PCBs and NP were the main organic pollutants among the three studied which have caused pollution pressure on R. philippinarum in Laizhou Bay coastal area.

This study reports the implications of silver nanoparticles (AgNPs) and cow-dung contamination on water quality and oxidative perturbations in antioxidant biomarkers in the exposed Clarias gariepinus. Sixteen samples of C. gariepinus were exposed to fresh-water, 0.75 mg/mL each of AgNPs, cow-dung and a mixture of AgNPs-cow dung dosed water for 10 days. Cow-dung significantly (p muscle > gill > liver, implying the kidney was the worst affected organ. The AgNPs significantly (p

Diclofenac (DCF) is a very common pharmaceutical that, due to its high use and low removal rate, is considered a prominent contaminant in surface and groundwater worldwide. In this study, Solanum lycopersicum L. cv. Micro-Tom (tomato) was used to disclose the role of glutathione (GSH)-related enzymes, as GSH conjugation with DCF is a well reported detoxification mechanism in mammals and some plant species. To achieve this, S. lycopersicum plants were exposed to 0.5 and 5 mg L−1 of DCF for 5 weeks under a semi-hydroponic experiment. The results here obtained point towards an efficient DCF detoxification mechanism that prevents DCF bioaccumulation in fruits, minimizing any concerns for human health. Although a systemic response seems to be present in response to DCF, the current data also shows that its detoxification is mostly a root-specific process. Furthermore, it appears that GSH-mediated DCF detoxification is the main mechanism activated, as glutathione-S-transferase (GST) activity was greatly enhanced in roots of tomato plants treated with 5 mg L−1 DCF, accompanied by increased glutathione reductase activity, responsible for GSH regeneration. By applying a targeted gene expression analysis, we provide evidence, for the first time, that SlGSTF4 and SlGSTF5 genes, coding for GSTs from phi class, were the main players driving the conjugation of this contaminant. In this sense, and even though tomato plants appear to be somewhat tolerant to DCF exposure, research on GST activity can prove to be instrumental in remediating DCF-contaminated environments and improving plant growth under such conditions.

Morchella is a genus of edible fungi with strong resistance to cadmium (Cd) and the ability to accumulate it in its mycelia. However, the mechanisms underlying Cd resistance in Morchella remain unknown. In the present study, morphological and physiological responses to Cd were evaluated in the mycelia of Morchella spongiola. Variations in hyphal micromorphology, including twisting, folding, and kinking, in mycelia exposed to different Cd concentrations (0.15, 0.9, 1.5, 2.4, 5.0 mg/L) were observed using scanning electron microscopy. Deposition of Cd precipitates on cell surfaces (at Cd concentrations >2.4 mg/L) was shown by SEM-EDS. Transmission electron microscopy analysis of cells exposed to different concentrations of Cd revealed the loss of intracellular structures and the localization of Cd depositions inside and outside the cell. FTIR analysis showed that functional groups such as C=O, –OH, –NH, and –CH could be responsible for Cd binding on the cell surface of M. spongiola. In addition, intracellular accumulation was observed in cultures at low Cd concentrations (

The release of a large quantity of heavy metals into the Dhaleswari River from the tannery, dyeing, and other industrial setups and their subsequent transfer to food chains through fish consumption have been an alarming issue in Bangladesh. To study the pollution level, a total of seven fish species, namely Heteropneustes fossillis, Channa punctata, Nandus nandus, Chanda nama, Anabas testudineus, Mystus gulio, and Colisa fasciata, were collected in winter from the Dhaleswari River and the total concentrations of Cr, Pb, Ni, and Zn in head and body tissues were analyzed separately. The concentrations of Cr, Pb, and Zn were found 300, 20, and 10 times higher, respectively, than the guideline value of the Food and Agriculture Organization (FAO)/World Health Organization (WHO), indicating possible health risks to humans. In most cases, bioaccumulation factors (BAFs) exceeded the highest limit, expressing that most of the species, especially C. nama, A. testudineus, and C. fasciata, were in the highly bioaccumulative state. The health risks associated with fish consumption were determined in terms of estimated daily intake (EDI), non-carcinogenic risks (THQ), and carcinogenic risk (TR) factors. The THQs for Cr and Pb crossed the maximum value of 1 in all the fish species except Pb in Mystus gulio, which might cause different non-carcinogenic diseases upon consumption of these fishes. In all the fish species, the carcinogenic risk factor for Cr exceeded the standard value (10-4), indicating chronic cancer risk to humans. Although the estimated daily intake (EDI) values did not cross the permissible limit, continuous consumption of contaminated fish from the target area may cause serious health complications. This study revealed that consumption of these fishes exposed people to a higher risk of non-carcinogenic and carcinogenic consequences in terms of human health.

Hybrid watermilfoil is becoming more prevalent in many lakes where the invasive Eurasian (Myriophyllum spicatum, EWM) and native northern watermilfoil (M. sibiricum) co-occur. These Eurasian and northern watermilfoil hybrids (HWM) grow 30% faster and in many cases are less sensitive to 2,4-dichlorophenoxy acetic acid (2,4-D) than either parent. The mechanism(s) impacting 2,4-D tolerance in these hybrids was investigated by comparing the absorption, translocation, metabolism, and desorption of two 2,4-D formulations in EWM and HWM.2,4-D absorption in EWM and HWM was 5.7 and 7.9 times the external herbicide concentration determined by the plant concentration factor, a metric used to determine herbicide bioaccumulation, and 2,4-D butoxyethyl ester absorption was 35.6 and 52.1 times the external concentration in EWM and HWM, respectively. Herbicide bioaccumulation was greater in HWM than in EWM. Herbicide translocation to HWM roots was limited at 192 HAT and herbicide desorption in HWM was slightly lower than EWM. No differences were found in herbicide metabolism between the two plant species.2,4-D resistance in HWM is not due to non-target-site resistance as no differences in herbicide absorption, translocation, desorption and/or metabolism were identified; therefore, target-site resistance is the most likely resistance mechanism. More research is needed to identify the molecular basis for the 2,4-D-resistant trait in HWM. © 2021 Society of Chemical Industry.

Ongoing inputs, in the form of sediment deposition along with associated dissolved contaminants, have challenged the assessment of cap performance at contaminated sediment sites. To address this issue, thin 2–3 cm layer sand caps amended with activated carbon (AC) were investigated for the remediation of polychlorinated biphenyl (PCB) contaminated marine sediments using 90-day mesocosms. All treatments were challenged with (1) ongoing clean or marker-PCB-spiked sediment inputs and (2) bioturbation. Bioaccumulation in hard clams (filter feeding near the cap-water interface) was evaluated to best understand cap effectiveness, relative to sheepshead minnows (confined to the surface water) and sandworms (which burrowed through the caps). All caps (sand and AC amended sand) provided isolation of native bedded PCBs (i.e., PCBs sourced from the bed), reducing uptake in organisms. Total PCB bioaccumulation in clams indicated that AC addition to the cap provided no benefit with spiked influx, or some benefit (56% reduction) with clean influx. Spiked input PCBs, when added to the depositional input sediment, were consistently detected in clams and passive samplers, with and without AC in the cap. PCB uptake by passive samplers located in the caps did not reflect the performance of the remedy, as defined by clam bioaccumulation. However, PCB uptake by passive samplers in the overlying water reasonably represented clam bioaccumulation results.

Over the last decade, increasing proliferations of Atlantic Sargassum populations have led to massive beaching with disastrous environmental consequences. This study is a preliminary assessment of open ocean Sargassum spp. element concentration to assess their potential contribution on coastal ecosystems. Sargassum spp. samples from seven sites, collected along a transect from the center of the Atlantic Ocean to near the coast of Martinique (French West Indies), were analyzed to determine their potential metal and metalloid enrichment. Mean element concentrations from the Sargassum spp. samples were ranked in the following descending order: As > Fe > Mn > Al > Zn > V > Ni > Cu > Cr > Cd > Hg. Element concentrations are relatively low compared to previous results of beached Sargassum spp. except for As that need to be carefully considered before reusing Sargassum spp.

In recent years, air pollution has increased significantly due to anthropogenic factors and has become a global problem. Heavy metals in air pollution components; it is of particular importance because they are not easily degraded and disappeared in nature, bioaccumulation in living bodies, some of them can be toxic, toxic or carcinogenic even at low concentrations and even those necessary for living bodies can be harmful at high concentrations. Therefore, monitoring the concentrations of heavy metals in the air is of great importance for human and environmental health. Biomonitoring is the most suitable method for monitoring the concentration of heavy metals. Plants that can accumulate heavy metals in different organs are suitable biomonitors. However, the most appropriate type and organ for monitoring each heavy metal must be determined separately. In this study, the changes in the concentrations of the elements Cr and Mn in Robinia pseudoacacia, Platanus orientalis, Acer negundo, Ulmus minor and Nerium oleander species were determined by the individuals who grow in areas where there is no traffic, less and dense. The Cr and Mn concentrations in the leaves, bark and wood of the species subject to the study were evaluated. Within the scope of the study, the washing process was also applied to the leaves and shells and the effect of the washing process was tried to be determined. As a result of the study, it was determined that the concentrations of each element in different species vary depending on the traffic density and this change can vary greatly on the basis of element and species.

Omega fatty acids, major importance in the prevention or treatment of a range of human diseases or disorders related with inflammation. These fatty acids are found in transgenic plants, fungi, and animals and even in microorganisms but in major amounts can be extracted from fatty fish. However, due to bioaccumulation of fat-soluble vitamins and high levels of saturated and omega-6 fatty acids, they may have deleterious health effects. It becomes necessary to search for novel and rich sources containing omega-3 fatty acids and one of the alternatives include fungi. The present study deals with production and purification of omega-3 fatty acids from Trichoderma viride and Aspergillus niger. In the present study, the main objective was to explore the beneficial effects of fungi for the maximum lipid production through optimized conditions and the results clearly showed that Trichoderma viride was the significantly highest lipid producer, with lipid production at initial pH 6.0 and incubation temperature 40℃.

The abuse of antibiotics in modern life and aquaculture has become a worldwide problem. Trace amounts of antibiotics discharged into natural water are increased in organisms through bioaccumulation and ultimately harm human health. Herein, we report a metal-tagged CRISPR/Cas12a bioassay and apply it to an ultrasensitive and highly selective evaluation of antibiotics bioaccumulation in wild fish samples. We integrated an element-tagging report probe and collateral cleavage activity of CRISPR/Cas12a. With the recognition and capture of target kanamycin by a "locked-activated" system, the activator strand was subsequently released to activate the collateral cleavage activity of Cas12a, followed by the cleavage of free Tm-Rep. After SA-MB capture, the biotin terminal was modified, and the uncleaved probe of Tm-Rep was removed. The acidized supernate containing the element tag fragment could be directly detected with 169Tm isotope monitoring by inductively coupled plasma mass spectrometry (ICPMS). With CRISPR/Cas12a biosensing and metal isotope detection by ICPMS, ultrasensitive and fast antibiotics analysis was realized with multiplex detection potential. Taking kanamycin as a modal analyte, a limit of detection as low as 4.06 pM was provided in a 30 min detection workflow. Besides, the bioaccumulation effect of kanamycin in a wild fish sample was also evaluated using the proposed strategy. We investigated the geographical distribution with Pseudorasbora parva samples collected in four different locations along a 600 km stretch of the Yangtze River. In addition, the bioaccumulation kinetics of antibiotics was evaluated in serum, muscle, and liver tissues of Pseudorasbora parva with 7 days of continuous feeding in a kanamycin-enriched environment.

The search for solutions to environmental pollution has been on the increase, with many questions recently as to which marine organisms can bioaccumulate trace elements in the marine ecosystem. Cadmium, Cr, Cu, Fe, Mn, Ni, Pb, and Zn concentrations in sediment, seawater, and seagrass compartments (root, rhizome, and leaf blade) were determined at Rabigh lagoon, Red Sea. This is to provide an insight into the potential of Cymodocea serrulata to bioaccumulate trace elements and as a good candidate to biomonitor these elements in a natural aquatic ecosystem. Results revealed significant variations in trace element concentrations across the three compartments of C. serrulata and the sites, with site S8 located in the most closed part of the lagoon recording the highest concentrations for all the trace elements. The translocation factor (TFrhizome/root = 1.00) of trace elements was higher in the root compartment. This implies that the root compartment is a better bioindicator of trace elements and has more potential to be utilized for biomonitoring. A significant positive correlation (p

Toxic cyanobacteria blooms have been reported in freshwater sources worldwide and may lead to aquatic biota toxin accumulation and trophic chain transfer, resulting in ecological and public health concerns. To assess cyanobacteria effects on microcystin uptake and accumulation and on phosphatase, acethylcholinesterase (AChE) and carboxylesterase (CarbE) enzymatic activities, an in vivo experiment was carried out employing the golden mussel Limnoperna fortunei. These mussels were exposed to a Microcystis aeruginosa NPLJ-4 strain (NPLJ-4) for 48 hours at different cell densities. Subsequently, algal cell counts were carried out and enzymatic activities were assayed. All three enzymes (Phosphatase, AChE and CarbE) were inhibited at the end of the exposure experiment. Mussels exposed to higher in vivo M. aeruginosa densities exhibited microcystin uptake and accumulation. In vitro assays were also carried out, exposing soluble L. fortunei enzyme fractions to M. aeruginosa extracts containing microcystin, and phosphatase inhibition was observed, whereas acetylcholinesterase and carboxylesterase were not inhibited. The results indicate that metabolites other than mycrocystin probably caused the observed in vivo esterase inhibitions, requiring further investigations.

Polycyclic aromatic hydrocarbons (PAHs) are considered as import contaminants portraying diverse ecological and public health apprehension due to their properties such as water solubility, toxicity, bioaccumulation potential and recalcitrant nature. Due to their contrary impact on the human wellbeing and other organisms in the biosphere, research is in progress to remove PAHs from the environment. Several physicochemical methods can be used for the removal of PAHs; however, its bioremediation using microorganisms is a benign and ecofriendly approach. Various strains of bacteria and microalgae are capable to potentially degrade or transform PAHs through their indigenous metabolic pathways. However, their biodegradability potential hindered by the cytotoxic effect of petroleum hydrocarbons, unfavorable environmental conditions, metabolic constrains, hydrocarbon composition, concentration, type and number of microorganisms. During the last decade, different microalgae species have been reported capable of biodegrading PAHs. Moreover, the interaction between microalgae and bacteria PAH metabolic pathways overcomes some rate limiting step(s) observed in single species. Thus, an alternative paradigm “Microalgae–Bacteria Consortia” is emerging as a new strategy to be adopted for the efficient detoxification and removal of the PAH pollutants. This review article aimed to provide an update of the current knowledge on the toxic effects of PAHs in various organisms as well as the symbiotic interactions between different bacteria and microalgae species in the degradation/transformation of PAHs. In addition, environmental factors are highlighted to elucidate how PAHs influence the growth of microalgae within a symbiotic framework with bacteria counterpart. The ultimate outcome of this paper can be beneficial to expedite the progress of new research into the bioremediation of PAHs from the contaminated environments.

Bioconcentration and bioaccumulation levels of lead, zinc, iron and arsenic in Scirpus californicus of the Paca and Tragadero Lagoons, Jauja, Peru, were evaluated. Water, sediment and Scirpus californicus samples were collected from each lagoon, which were transported to the laboratory for the analytical determination of lead, iron, zinc and arsenic, which was performed by atomic absorption spectrophotometry based on the methodology recommended by FAO. The results obtained reveal the current status of the quality of the aquatic environment of natural wetlands in the central region of Peru in terms of heavy metals and arsenic, which provide an important source of water for the populations of large cities in the central region of Peru. The presence of heavy metals and arsenic with great impact on the quality of these water bodies may be due to the pressure exerted by anthropogenic activities such as mining, agriculture, industrial and domestic wastewater. The sediments of Paca and Tragadero Lagoons showed high concentrations of Fe, exceeding international standards. Aquatic vegetation represented by Scirpus californicus in both lagoons bio accumulated mainly Zn, without exceeding international standards. Resumo Foram avaliados os níveis de bioconcentração e bioacumulação de chumbo, zinco, ferro e arsênio em Scirpus californicus das lagoas Paca e Tragadero, Jauja, Peru. Amostras de água, sedimento e Scirpus californicus foram coletadas de cada lagoa, as quais foram transportadas ao laboratório para a determinação analítica de chumbo, ferro, zinco e arsênio que foi realizada por espectrofotometria de absorção atômica com base na metodologia recomendada pela FAO. Os resultados obtidos revelam o estado atual da qualidade do ambiente aquático dos pântanos naturais da região central do Peru em termos de metais pesados e arsênio que constituem uma importante fonte de água para as populações de grandes cidades da região central do Peru. A presença de metais pesados e arsênio com grande impacto na qualidade desses corpos d'água pode ser decorrente da pressão exercida por atividades antrópicas como mineração, agricultura, efluentes industriais e domésticos. Os sedimentos das lagoas Paca e Tragadero apresentaram altas concentrações de Fe, superando os padrões internacionais. A vegetação aquática representada por Scirpus californicus em ambas as lagoas mostra bioacumulação principalmente de Zn, sem ultrapassar os padrões internacionais.

The present study investigated the water quality index (WQI) of the Kshipra river at Dewas, Madhya Pradesh, India, using native fish Labeo rohita, and plant Eichhornia crassipes. The temperature, pH, dissolved oxygen, alkalinity, turbidity, and dissolved solids were found to be within the prescribed limits. However, heavy metals concentration exceeded the limit except for Cu and Zn. Their occurrence in river water was as follows: Ni > Fe > Cd > Cr > Mn > Zn > Cu. Among these heavy metals, Cd was found to be highly bioavailable, whereas Zn was the least bioavailable metal. Based on WQI, the water was found to be unfit for drinking, and the high WQI value was due to the presence of Cr and Cd. In fish tissues (muscle, liver, gut, gills, and kidney), the highest and lowest metal pollution index was found in gills (45.03) and kidneys (12.21), respectively. Bioaccumulation of these metals resulted in significant depletion of energy reserves (protein, glucose, and glycogen) and also altered hematological parameters. Moreover, liver function tests showed hepatic damage in the exposed fish. In-plant, both the bioaccumulation and mobility factor exceeded 1 for all these metals. On the other hand, the translocation factor was found to be beyond 1 for Fe, Ni, and Zn. These high values make this plant fit for phytoextraction of Mn, Fe, Cu, Zn, and Cd and phytostabilization of Cr in water. Moreover, consumption of L. rohita from the Kshipra River does not pose a non-cancer risk as the target hazard quotient was below 1, but it may pose cancer risk because of the presence of Cr in the range of 1.402 × 10−3 to 1.599 × 10−3.

Bats have been proposed as reliable bioindicators for monitoring bioaccumulation of elements and chemicals in natural and transformed ecosystems. Non-invasive methods are becoming more popular as research moves away from destructive methodologies. We present the first concentrations of 23 elements in Mops condylurus and Tadarida aegyptiaca (Molossidae) fur and blood from an opencast diamond mine and reference area using inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of B, K, Rb and Cd in the bats’ fur were significantly higher in the mining footprint compared to the reference area (P < 0.05). Other elements such as Zn and Hg were significantly higher in the blood of bats from the mining footprint than the reference area (P < 0.05), whereas Mn was significantly higher in the blood of bats from the reference area than from the mining footprint (P < 0.05). Sixteen of the 22 elements above the limit of detection, with the exception of Ba, were significantly higher in the fur samples than in the blood due to elements being incorporated over time into the fur as it grows, whereas blood reveals short-term exposure to elements. Concentrations of most of the elements were reasonably low except Al, Fe and Zn. In general, the element concentrations particularly in the fur samples were comparable with other international studies reporting elemental fur concentrations from anthropogenically impacted and natural areas. Fur and blood have the potential to be viable indicators of environmental toxicity, but research is required on toxic thresholds and physiological and ecological unknowns around element concentrations in bat tissues and organs.

A high proportion of populations in most developing countries live below the poverty line and those near refuse grounds resort to dumpsite farming to grow food. Consequently, high levels of waste-derived contaminants are found in crops consumed by these people. This study investigates the extent to which crops cultivated on the Mbale dumpsite (Uganda) were contaminated by 11 metals and 2 non-metals: iron (Fe), aluminum (Al), zinc (Zn), manganese (Mn), copper (Cu), mercury (Hg), lead (Pb), nickel (Ni), cobalt (Co), cadmium (Cd), selenium (Se), chromium (Cr), and arsenic (As). We investigated how element bioaccumulation in crops was influenced by the growth period (short- and long-term crop maturity). The short-term crops were Zea mays and Amaranthus cruentus, whereas the long-term crops were Manihot esculenta, Colocasia esculenta, Musa acuminata, Carica papaya, Coffea arabica, and Saccharum officinarum. Results showed that nine metals were present at concentrations above World Health Organization/Food and Agriculture Organization (WHO/FAO) food safety recommendations and hence may pose health risks to consumers. In this study, leaves contained higher metal concentrations than other analyzed consumable parts. Pb and Co were found at higher concentrations in leaves of short-term crops than in long-term crops. Among short-term crops, only Z. mays seeds contained permissible metal concentrations by WHO/FAO standards. The growth period was also found to influence metal bioaccumulation in crop types. Pb, Co, Fe, Al, and Cu concentrations were significantly higher in the short-term crops than in long-term crops, while Mn, Ni, and Cr concentrations were higher in long-term crops than in short-term crops. Overall, public awareness about the health risks associated with consuming short-term leafy crops grown on dumpsites should be improved to reduce toxic metal exposure. While implementing such a campaign, the food supply of individuals whose survival depends on such crops should not be jeopardized. Therefore, farmers need alternative farming areas outside dumpsites. Integr Environ Assess Manag 2022;18:1056-1071. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental ToxicologyChemistry (SETAC).

The uptake potential of fragrance encapsulates by aquatic or terrestrial organisms was investigated. Because of their size of5 mm and their polymeric nature, fragrance encapsulates fall under the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection definition of microplastics. After use, fragrance encapsulates enter the sewer system and reach the sewage treatment plant (STP), where90% of them are likely to be removed by sorption to the sludge. When the STP-generated sludge is used as fertilizer for agricultural soils, this may lead to potential exposure of terrestrial invertebrates to fragrance encapsulates, especially those feeding on particles of a similar size as the fragrance encapsulates. Two aquatic (Corbicula fluminea [water exposure] and Hyalella azteca [water and dietary exposure]) and one terrestrial invertebrate (Eisenia andrei [soil exposure]) species were exposed to 50 mg/L (or mg/kg) double fluorescence-labeled fragrance encapsulates (diameter 5-50 µm). The results showed that fragrance encapsulates are available to aquatic and terrestrial invertebrates but that species-specific differences regarding the ability to ingest fragrance encapsulates may exist. The benthic grazer H. azteca showed no ingestion of fragrance encapsulates, whereas the capsules were readily ingested and egested by the unselective freshwater filter feeder C. fluminea as well as the terrestrial decomposer E. andrei. No signs of bioaccumulation of fragrance encapsulates were indicated by microscopic assessment. Environ Toxicol Chem 2022;41:931-943. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Microplastics can accumulate residual drugs and heavy metals in the environment and accumulate through the layers of the food chain, ultimately causing harm to human health. The pollution of microplastics in the freshwater environment is becoming more and more serious, which directly affects the safety of aquatic organisms. This experiment studied the effects of single and composite microplastics and Cd on the tissue damage, antioxidant, and immune response of juvenile Channa argus. Microplastics with different diameters of 80 nm, 0.5 μm (200 μg/L), and Cd (50 μg/L) were used for exposure, and four sampling points were set for 24 h, 48 h, 96 h, and clear 48 h. Under different treatments, a certain degree of gill tissue damage can be found in 96 h. Microplastics and Cd can cause oxidative stress and affect the antioxidant status, and the impact of 0.5-μm microplastics is stronger than that of 80-nm microplastics. There is an antagonistic effect between the two microplastics and Cd during compound exposure, but the activity of CAT shows a synergistic effect. Microplastics and Cd affect the expression of immune-related genes to varying degrees. When exposed together, the expression of HSP70 gene all showed mutual antagonism, while the expression of IL-1β gene was different. The expression of the MT gene can infer the ability of microplastics to accumulate Cd, and microplastics with a small diameter of 80 nm have stronger enrichment capabilities.

The recovery of valuable metals from waste electrical and electronic equipment (WEE or e-waste) might be achieved by bioleaching, a microbial-based technology which can substitute in the future chemical-based processes, reducing environmental impacts. Although marine fungi are still little exploited for such purposes, they are potential interesting targets. In the present study, we isolated marine fungi from contaminated sediments collected in two coastal areas (Bagnoli-Coroglio Bay, Italy; Bilbao estuary, Spain) and identified four high tolerant fungal taxa to high concentration of e-waste (100 g L−1). Such fungal taxa, belonging to the fungal families Dipodascaceae, Microascaceae, Gymnoascaceae and Trichocomaceae, were tested for their bioleaching and bioaccumulation potential of metals present in e-waste, using different experimental approaches. Results reported here indicate that the fungi are able to bioaccumulate metals released from e-waste with an efficiency depending from fungal strains and metals considered. Among precious elements, platinum was highly concentrated within fungal biomass (31–62%) across all strains. Our findings provide new insights on the potential of marine fungi inhabiting highly contaminated marine sediments as promising candidates to be used for the recovery of precious metals from electronic waste.

Sorites marginalis as one of the benthic foraminifer's genera were collected from three coastal lagoons (Abu Shaar, Umm al-Huwaytāt, and Marsa Shūni) on the Egyptian Red Sea coast and investigated for their 226Ra, 232Th, and 40K content using HPGe gamma-ray spectrometry. S. marginalis shells show high radioactivity levels with average activity concentration values of 251.8 ± 18.3, 86.8 ± 7.7, and 791.2 ± 57.6 Bq kg-1, 327.1 ± 11.4, 97.4 ± 7.1, and 751.6 ± 54.7 Bq kg-1, 246.6 ± 17.7, 65.1 ± 4.8, and 477.6 ± 34.8 Bq kg-1 for 226Ra, 232Th, and 40K in the samples from Abu Shaar, Umm al-Huwaytāt, and Marsa Shūni, respectively. 226Ra and 40K have a high tendency to accumulate in S. marginalis compared to 232Th. High bioaccumulation of the studied radionuclides was found for samples from Umm al-Huwaytāt and Abu Shaar lagoons. Radiological parameters such as radium equivalent activity, gamma absorbed dose rate in air, and outdoor annual effective dose were calculated, and values higher than the permissible limits were obtained. Based on the obtained results, the estimation of radioactivity levels in S. marginalis shells may serve as an indicator of marine environment pollution.

Biotransformation may substantially reduce the extent to which organic environmental contaminants accumulate in fish. Presently, however, relatively little is known regarding the biotransformation of ionized chemicals, including cationic surfactants, in aquatic organisms. To address this deficiency, a rainbow trout liver S9 substrate depletion assay (RT-S9) was used to measure in vitro intrinsic clearance rates (CLint ; ml min-1 g liver-1 ) for 22 cationic surfactants that differ with respect to alkyl chain length and degree of methylation on the charged nitrogen atom. None of the quaternary N,N,N-trimethylalkylammonium compounds exhibited significant clearance. Rapid clearance was observed for N,N-dimethylalkylamines, and slower rates of clearance were measured for N-methylalkylamine analogs. Clearance rates for primary alkylamines were generally close to or below detectable levels. For the N-methylalkylamines and N,N-dimethylalkylamines, the highest CLint values were measured for C10 -C12 homologs; substantially lower clearance rates were observed for homologs containing shorter or longer carbon chains. Based on its cofactor dependency, biotransformation of C12 -N,N-dimethylamine appears to involve one or more cytochrome P450-dependent reaction pathways, and sulfonation. On a molar basis, N-demethylation metabolites accounted for up to 25% of the N,N-dimethylalkylamines removed during the 2-h assay, and up to 55% of the removed N-methylalkylamines. These N-demethylation products possess greater metabolic stability in the RT-S9 assay than the parent structures from which they derive and may contribute to the overall risk of ionizable alkylamines. The results of these studies provide a set of consistently determined CLint values that may be extrapolated to whole trout to inform in silico bioaccumulation assessments. Environ Toxicol Chem 2021;40:3123-3136. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

This study was conducted to measure concentrations of cadmium (Cd), lead (Pb), arsenic (As), mercury (Hg), copper (Cu), chromium (Cr), and iron (Fe) in blood serum and feces of mugger crocodile (Crocodylus palustris) and in water and sediment of their habitat (Negour site, Chabahar County in Sistan and Baluchistan Province, Iran). Heavy metal contents in crocodile serum and feces, water, and sediments were analyzed by inductively coupled plasma optical emission spectrometry (ICP–OES spectrometer—Spectro Genesis). The highest levels of heavy metals in the mugger crocodile’s serum were Fe > Hg > Pb > Cr > Cu > Cd > As, respectively. The total metal concentrations in the feces exhibited the following decreasing order from Fe > As > Pb = Cr > Hg > Cd > Cu. The highest average levels of heavy metals in water were Hg > Fe > As > Pb > Cu > Cr > Cd respectively and As > Fe > Pb > Cu > Hg > Cd > Cr in the sediment of lagoons. A significant difference was observed in the concentration of Fe and Pb between male and female crocodiles. Moreover, correlation analysis indicated significant negative correlations between sex and bioconcentrations of Cd, Fe, Pb, As, and Hg in the serum. In conclusion, this study showed that the environmental conditions of Negour lagoons are not suitable for crocodiles regarding habitat health and water quality. Furthermore, since these lagoons and fish are the most important sources of drinking water and seafood for the residents of the area, contamination of these pools with heavy metals can also threaten people’s health.

The presence of microplastics within the gut of animals is well documented. Whether microplastics bioaccumulate in organisms and biomagnify in food webs remains unclear and relies on the ability of microplastics to translocate to other tissues. Here, we demonstrate the widespread presence of microplastics and other anthropogenic microparticles in the gastrointestinal tract, fillet, and livers of seven species of sportfish from Lake Simcoe, Ontario, Canada. Larger fish had a higher microplastic load compared to smaller fish, but the opposite trend was observed with translocated microplastics standardized by fish mass (i.e., smaller fish contained more translocated particles per gram wet weight than larger fish). Moreover, we observed no evidence of biomagnification as there was no significant relationship between the trophic level and total or translocated microplastics per individual. Overall, this suggests that microplastics are translocating, but that excretion of translocated particles or growth dilution may be occurring rather than bioaccumulation and biomagnification. Moreover, the assemblages of shapes and material types varied among tissues, suggesting that particle characteristics may predict biological fate. Our findings highlight the need for further work to understand the mechanisms of microplastic translocation and excretion and the implications for the dynamics of microplastics accumulation in food webs and human exposure.

Detrimental effects of chemical pollution-primarily caused by human activities-on aquatic ecosystems have increasingly gained attention. Because of its hydrophobic qualities, mercury is prone to easily bioaccumulate and biomagnify through the food chain, decreasing biodiversity and eventually also affecting humans. In the present study, accumulated mercury concentrations were measured in muscle and liver tissue of perch (Perca fluviatilis) and European eel (Anguilla anguilla) collected at 26 sampling locations in Flemish (Belgian) waterbodies, allowing a comparison of these species within a variety of environmental situations. Furthermore, effects of size and weight have been assessed, expected to influence accumulation and storage of pollutants. Mercury concentrations in perch ranged up to 1.7 mu g g(-1) dw (median: 0.29 mu g g(-1) dw) in muscle and from 0.02 to 0.77 mu g g(-1) dw (median: 0.11 mu g g(-1) dw) in liver tissue. For eel, these concentrations were between 0.07 and 1.3 mu g g(-1) dw (median: 0.39 mu g g(-1) dw) and between 0.08 and 1.4 mu g g(-1) dw (median: 0.55 mu g g(-1) dw) respectively. We found a correlation of accumulated mercury with length in perch, independent of location. Furthermore, a significant difference in accumulated mercury concentrations between the targeted species was measured, with the highest mean concentrations per dry weight in eel liver and muscle tissue. In perch, higher concentrations were found in muscle compared to liver tissue, while in eel, liver tissue showed the highest concentrations. These findings were further considered with concentrations corrected for lipid content, excluding the fat compartment, which is known to a hold negligible portion of the total and methyl mercury concentrations. This confirmed our previous conclusions, except for mercury concentrations in eel. Here there was no longer a significant difference between muscle and liver concentrations. Finally, health risk analyses revealed that only frequent consumption of local eel (> 71 g day(-1)) could pose risks to humans.

Papiliotrema huenov was previously reported to be highly tolerant of a range of extremely toxic heavy metals. This study aimed to identify the potential of P. huenov to remove manganese and copper from aqueous solution. Physical conditions which affect removal of Mn(II) and Cu(II) were determined. Optimal temperature for adsorption of both metal ions was 30 °C, and optimal pH for maximum uptake of Mn(II) and Cu(II) were 5 and 6, respectively. Under these conditions, living cells of P. huenov accumulated up to 75.58% of 110 mg/L Mn(II) and 70.5% of 128 mg/L Cu(II) over 120 h, whereas, the removal efficiency of metal ions by dead cells over 1 h was 60.3% and 56.5%, respectively. These results indicate that living cells are more effective than dead biomass for bioremediation, but that greater time is required. The experimental data extends the potential use of P. huenov in biosorption and bioaccumulation of toxic heavy metals to copper and manganese, two of the most common industrial contaminants.

The concentrations of As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn (TE) in four juvenile fishes (Acestrorhynchus pantaneiro, Salminus brasiliensis, Brycon orbignyanus, and Megaleporinus obtusidens) and associated sediment water from the Lower Parana River were measured. For muscle, gills, and liver fishes, the TE accumulation in the muscle, gills, and liver was evaluated. The TE concentration was measured by quadrupolar inductively coupled plasma mass spectrometry (Q-ICP-MS). Cadmium (0.25 ± 0.07 μg L−1), Cu (3.00 ± 1.44 μg L−1), Fe (612 ± 69 μg L−1), and Pb (1.92 ± 1.20 μg L−1) in water and As (4.1–6.9 μg g−1), Cr (20.1–31.4 μg g−1), Cu (10.7–19.2 μg g−1), Mn (351.3–482.2 μg g−1), and Ni (24.5 ± 10.9 μg g−1) in sediments exceeded the guide values for the conservation of aquatic life. In general, muscle of omnivorous species (B. orbignyanus and M. obtusidens) showed higher values of elements than those of carnivorous species (A. pantaneiro and S. brasiliensis). However, TE concentrations varied with fish species and organs. Independently of the examined species, the highest concentrations of Cr and Pb were in the muscle and gills, respectively. Cadmium, Cu, and Fe concentrations were higher in the liver than in gills and muscle in all four fish species. These results were consistent with the tissue selectivity index analyzed. For the four species, major essential elements showed the highest accumulation. However, the accumulation of toxic elements in omnivorous fish was higher than in carnivorous fish. The individual pollution load index indicated that sediment was very polluted with As and Pb, but based on the combined ecological indexes, low elemental sediment pollution in the Espinillo Lake was revealed.