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Along with the growing utilization of zinc (Zn) and Zn-containing nanoparticles in various industries, Zn ecotoxicological evaluation on human food supply is necessary even though Zn is generally considered safe and rarely concentrated ecotoxicologically. This study aimed to investigate the bioaccumulation of Zn in 18 species of vegetables (seven leafy, nine fruity vegetables and one species each of tuber and legume) collected from two farming sites in the west coast of Peninsular Malaysia. A human health risk assessment (HHRA) was also conducted. In addition to HHRA based on the general population, HHRA based on each major ethnic group of the Malaysian society was also determined considering that the food consumption pattern would definitely be varied across ethnicities and age groups (children and adults). The study results showed that Zn concentrations were significantly higher (p < 0.05) in leafy vegetables than in other types of vegetables. However, the target hazard quotient (THQ) values were all found to be < 1.0. Therefore, based on the Malaysian ethnicities and age groups with their respective vegetable consumption patterns, the results indicated insignificant noncarcinogenic human health risk of Zn via oral consumption of vegetables by the Malaysian population. As a metric of measurement of HHRA, a comparison of THQ values could yield previously unreported insights into HHRA differences among the compared populations. A comparison of THQ values among the consumer groups indicated higher HHR for Chinese Malaysians and children due to their higher vegetable consumption and lower body weight, respectively. A comparison the Zn intakes of all the consumer groups with the recommended nutrient intakes indicated that the oral consumption of the vegetable species collected in this study would not result in Zn-related hazards and would not be able to fulfil the Zn dietary need of the individual consumer.

In this study, levels and sources of aliphatic hydrocarbons and hopanes in surface sediments collected from rivers and estuaries of Peninsular Malaysia were assessed. The concentrations of total n-...

Microplastics (MPs) are a modern societal concern and recognized as a growing environmental hazard by careless disposal. This study aimed to assess the MPs content in white shrimp (Metapenaeus affinis) inhabiting in a natural habitat affected by high anthropogenic pressures, and recognize if the shrimp could be a suitable bioindicator for MPs pollution. To assess spatial changes of MPs presence in shrimps, sampling was carried out by a trawl net from 13 stations across the entire Musa Bay. Tissues of shrimps were examined for MPs following floatation, digestion, microscopic observation and identified by Confocal Raman Spectroscopy. MPs were observed in the shrimps of all stations. The average MPs abundance was 1.02 items/g of digestive tissues. About 37% of recorded MPs in M. affinis samples exceeding 500 μm that could be related to surface area and stickiness as notable controls beyond ingestion. The dominant shape of MPs was fiber, followed by film. Five different colors were recorded in tissues of M. affinis samples, and the white/transparent MPs were the most abundant, followed by blue and black. In addition, a wide range of recorded colors of MPs in the study area could suggest a variety of sources of MPs. Confocal Raman Spectroscopy confirmed that polyethylene terephthalate (46%), polypropylene (27%) and polystyrene (27%) were dominant polymers. As the average annually consumption of shrimp in the region is 2.3 g/person/day, therefore each person could consume 857 MPs per year. In conclusion, the results of this research provide a detailed and useful information for a better understanding of MPs contamination in the region and suggest Jinga shrimp as a suitable species for monitoring MPs in marine ecosystems.

The invasive weed Asystasia gangetica was investigated for its potential as a biomonitor and as a phytoremediator of potentially toxic metals (PTMs) (Cd, Cu, Ni, Pb, and Zn) in Peninsular Malaysia owing to its ecological resistance towards unfavourable environments. The biomonitoring potential of PTMs was determined based on the correlation analysis of the metals in the different parts of the plant (leaves, stems, and roots) and its habitat topsoils. In the roots, the concentrations (mg/kg dry weight) of Cd, Cu, Ni, Pb, and Zn ranged from 0.03 to 2.18, 9.22 to 139, 0.63 to 5.47, 2.43 to 10.5, and 50.7 to 300, respectively. In the leaves, the concentrations (mg/kg dry weight) of Cd, Cu, Ni, Pb, and Zn ranged from 0.03 to 1.16, 7.94 to 20.2, 0.03 to 6.13, 2.10 to 21.8, and 18.8 to 160, respectively. In the stems, the concentrations (mg/kg dry weight) of Cd, Cu, Ni, Pb, and Zn ranged from 0.03 to 1.25, 5.57 to 11.8, 0.23 to 3.69, 0.01 to 7.79, and 26.4 to 246, respectively. On the other hand, the phytoremediation potential of the five metals was estimated based on the bioconcentration factor (BCF) and the translocation factor (TF) values. Correlation analysis revealed that the roots and stems could be used as biomonitors of Cu, the stems as biomonitors of Ni, the roots and leaves as biomonitors of Pb, and all three parts of the plant as biomonitors of Zn. According to the BCF values, in the topsoil, the “easily, freely, leachable, or exchangeable” geochemical fractions of the five metals could be more easily transferred to the roots, leaves, and stems when compared with total concentrations. Based on the TF values of Cd, Ni, and Pb, the metal transfer to the stems (or leaves) from the roots was efficient (&gt, 1.0) at most sampling sites. The results of BCF and TF showed that A. gangetica was a good phytoextractor for Cd and Ni, and a good phytostabilizer for Cu, Pb, and Zn. Therefore, A. gangetica is a good candidate as a biomonitor and a phytoremediator of Ni, Pb, and Zn for sustainable contaminant remediation subject to suitable field management strategies.

The objective of this commentary is to promote the use of bivalves as biomonitors, which is a part of the continual efforts of the International Mussel Watch. This commentary is an additional discussion on “Bivalve mollusks in metal pollution studies: From bioaccumulation to biomonitoring” by Zuykov et al., published in Chemosphere 93, 201–208. The present discussion can serve as a platform for further insights to provide new thoughts and novel ideas on how to make better use of bivalves in biomonitoring studies. The certainty of better and more extensive applications of mollusks in environmental monitoring in the future is almost confirmed but more studies are urgently needed. With all the reported studies using bivalves as biomonitors of heavy metal pollution, the effectiveness of using Mussel Watch is beyond any reasonable doubts. The challenge is the development of more accurate methodologies for of heavy metal data interpretation, and the precision of the biomonitoring studies using bivalves as biomonitors, whether in coastal or freshwater ecosystems. Lastly, inclusion of human health risk assessment of heavy metals in commercial bivalves would make the research papers of high public interest.

The aim of this paper is to determine and discuss the Concentrations of Copper (Cu) in the different soft tissues of Perna viridis and surface sediments collected from western and eastern parts of Johore Singapore Causeway. In general, it is found that the different tissues of eastern mussel populations were found to have significant (p < 0.05) higher Cu levels than those in the western mussel populations. This indicated higher Cu bioavailability in the eastern part of causeway than that in the western part. The geochemical fractions (except for oxidizable-organic fraction) showed significant (p < 0.05) higher Cu levels in the eastern sediments than those in the western part of the causeway. This indicated higher Cu contamination in the eastern part of causeway than that in the western part. With consistent scientific reports of high metal levels in the eastern part of causeway between 2015-2018, it is predicted that there is a plausible constant source of anthropogenic metal contamination at the eastern part of the causeway beyond 2020 should there is no drastic effective control of the anthropogenic activities.

This study aimed to investigate the ecological risk assessment of Khamir, Tiyab, and Jagin estuaries and the impact of anthropogenic activities on these ecosystems during a one-year study period (April 2015 to March 2016) using trace metals as pollution indices. The sediment samples were collected from nine sampling stations, following a gradient of contamination from the industrial wastewater and shrimp farming effluents to the less impacted stations. Pollution indices (i.e. PERI and PLI) were applied to ascertain the sediment quality. Based on pollution indices, the overall pattern of environmental quality status demonstrated that industrial sewage and shrimp farming effluents are major sources of pollution in the Khamir and Tiyab estuaries, respectively. The sediments in the most stations in studied coastal ecosystems of Iran posed moderate or considerable ecological risk. Results from this study showed that Zn, Pb, Cu, and Cd were mostly derived from anthropogenic activities such as domestic sewage and industrial effluents. Also, the findings of this study revealed that the pollution indices are suitable for evaluating the environmental situation of coastal ecosystems and the separation of areas with less impacted by human activities from areas affected by these activities and could be used as a robust management tool for monitoring programs in coastal areas. Altogether, these findings could be useful in providing more effective and targeted strategies of development better management practices for coastal areas.

Harmful algal blooms (HABs) have had harmful effects on the health of a wide range of organisms and are becoming a noteworthy risk to fisheries, human health and wildlife around the globe. Although the lethal influences of dinoflagellate Margalefidinium / Cochlodinium polykrikoides have been well-documented for finfish, the impacts on decapod crustacean species, especially, Litopenaeus vannamei are poorly understood. Here, we examined the exposure of L. vannamei juveniles with different M. polykrikoides densities (T1: 1 × 103, T2: 2 × 103, T3: 3 × 103, T4: 9 × 103 and T5: 30 × 103 cells ml−1), in order to observe possible histological alterations in gills and hepatopancreas. After 96 h exposure, shrimp exhibited increased mortality and survival rate of juveniles in control group were meaningfully (P

This study aimed to analyse ten trace metal concentrations in the edible part of the freshwater clam Corbicula javanica and to provide a critical assessment of the potential risks to human health through consumption of this clam as food based on well-established indices and food safety guidelines. The clams were captured from a pristine original site and transplanted to other sites with different environmental qualities. The trace metal levels in the edible total soft tissue (TST) of the clam were below those of the food safety guidelines referred to except for Pb, which exceeded the permissible limit set by the European Commission (2006) and the US Food and Drug Administration/ Center for Food Safety and Applied Nutrition), Interstate Shellfish Sanitation Conference. (USFDA/CFSAN, ISSC) (2007). The estimated daily intake (EDI) values of the clam were found to be lower than the oral reference dose and the calculated target hazard quotient (THQ) and total THQ were found to be less than 1. Therefore, in conclusion, the human health risk for consumption of TST of C. javanica at both average and high-level were insignificant regardless of the environment it was exposed to.

Microplastic (MP) pollution of the marine environment is now a growing global concern posing a threat to a variety of species through the ingestion and transfer within food webs. This is considered a potential toxicological threat to marine species due to the chemical additives used to make many plastic products, or the persistent organic pollutants that may accumulate on them while residing in the environment. While the presence of MPs in the marine environment is widely documented, there are no other review articles providing a summary of published effect studies of MPs on the immune and reproductive systems of marine species. This manuscript reviews reproductive and immune-system changes in response to MPs in 7 and 9 species, respectively. Some species such as Mytilus galloprovincialis and oyster Crassostrea gigas were investigated in multiple papers. Most studies have been conducted on invertebrates, and only 3 studies have been performed on vertebrates, with exposure times ranging between 30 min and 60 days. A review of the literature revealed that the most common MPs types studied in relation to adverse impacts on immune system and reproductive success in marine species were polystyrene (PS) and polyethylene (PE). The immune system's responses to MPs exposure varied depending on the species, with altered organismal defense mechanisms and neutrophil function observed in fish and changes in lysosomal membrane stability and apoptotic-like nuclear alterations in phagocytes reported in invertebrate species. Reproductive responses to MPs exposure, varied depending on species, but included significant reduction in gamete and oocyte quality, fecundity, sperm swimming speed, and quality of offspring. The lack of published data means that developing a clear understanding of the impact across taxonomic groups with different feeding and behavioral traits is often difficult. Further work is required to better understand the risk MPs pose to the immune and reproductive systems of marine species in order to fully evaluate the impact these ubiquitous pollutants are having on marine ecosystems and the associated goods and services they provide.

The distribution and sources of PAHs in jinga shrimp (Metapenaeus affinis), and human health risks due to consumption was evaluated in collected samples from the Musa Bay, Persian Gulf. The total concentration of PAHs (∑16PAHs) ranged from 10 to 144 μg kg−1 dry weight, indicating low to moderate level of pollution. The PAHs were dominated by three- (41%) and two-ring (38%) compounds. Source identification analyses indicated the PAH pollution mostly originated from petroleum inputs. A preliminary evaluation of human health risk using chronic daily intake, hazard index, benzo[a]pyrene-equivalent (BaPeq) concentration (PEC) as well as the incremental life cancer risk and non-cancer risk assessment suggest low potential health risk for consumers of the Metapenaeus affinis. However, the results indicate minimal risks associated with the intake of PAHs via shrimp consumption, but long-term monitoring is required to evaluate the changes in ecological and human health impacts of contaminants in the region. Main finding PAHs in Metapenaeus affinis from Musa bay, which influenced by anthropogenic activities were low to moderate level of pollution. Human health risk indicates low potential health risk for consumers.

In this study, we analyse the fish species diversity and distribution patterns to determine the potential role of environmental variables as drivers of fish community structure and composition. Thus, we investigated the distributional patterns of estuarine fish and their environmental correlates along a broad spatial scale encompassing three subtropical estuaries from the Iranian coastal waters using multivariate techniques. According to their relative densities, the fish fauna was dominated by the following ten species: Leiognathus brevirostris (17.1 %), Valamugil seheli (16.4 %), Ambassis gymnocephalus (10.4 %), Gerres filamentosus (9.3 %), Gerres longirostris (7.4 %), Leiognathus bindus (7.2 %), Thryssa vitrirostris (4.6 %), Sillago sihama (4.1 %), Megalops cyprinoides (3.9 %), and Nematalosa nasus (3.8 %). Leiognathidae and Mugilidae, represented by seven and six species, contributed 26.17 % and 19.11 % of numerical abundance of the total catch. Hierarchical cluster analysis and nMDS showed a clear spatial segregation of stations from different parts of estuaries according to similarities in their species compositions. Canonical correspondence analyses indicated that temperature, dissolved oxygen, pH and salinity were the four main variables influencing the occurrence of fishes within the estuarine systems. Our results support the effectiveness of the mangrove forests on fish communities in subtropical estuaries subjected to multiple environmental changes. Overall, the details of these findings are beneficial to understanding and developing suitable conservation strategies for the restoration and management of fish resources in the Markazi, Khalasi and Gabrik estuaries, as well as the other estuaries of the Iranian coastal waters.

The pre sent study analyzed the relationships of two different biological assemblages (diatom and macroinvertebrate) when they are used to characterize a set of stations (from reference stations to impacted stations) within the Shahrood River. In particular, we examined the issue of concordance among these assemblages and the physicochemical parameters detected, using both multivariate and multimetric methods. In addition, the trophic diatom index and Hilsenhoff family-level biotic index for macroinvertebrate assemblages were used to evaluate the ecological status of the Shahrood River. Diatom and macroinvertebrate assemblages in the Shahrood River differed significantly between reference and impacted stations. ANOSIM showed a significant difference in the composition and abundance of diatoms and macroinvertebrates among reference, influence and impact stations, especially between reference and impact stations. Results of CCA ordination showed that benthic diatoms and macroinvertebrate assemblages were mainly affected by DO, TSS, NO3 −, PO4 3− concentrations and heavy metals such as Zn and Cd. Biotic indices for the Shahrood River suggested a water quality category of “fair” with fairly substantial organic pollution for the impacted stations. Finally, our results suggest that an appropriate management and restoration policy needs to be implemented for the Shahrood basin.

This research aimed to investigate the long-term spatiotemporal changes of surface water quality of the Maroon River by implementing Water Quality Index (WQI) and multivariate statistical analyses such as non-metric multidimensional scaling and cluster analyses, as complementary tools to investigate spatial variations in water quality parameters and also delineate areas in terms of water quality conditions in the period under study. The other purposes of this study were to evaluate the physicochemical properties of the Maroon River water and assess the effects of each water quality parameter on the WQI values. Relationship between quality scale of hydrochemical parameters and the resulting WQI scores was determined employing linear regression analysis. Moreover, the suitability of water quality was evaluated for irrigation purposes using conventional indices, electrical conductivity (EC), sodium adsorption ratio (SAR), and percent sodium (Na%). The monitoring stations were placed in high and very high categories according to the assessment of irrigation water quality with EC. Considering WQI, the upper (S1, S2, and S4) and lower (S3, S5, and S6) monitoring stations of the Maroon River distributed in category C3 (high salinity) and C4–C5 (very high salinity), respectively. The findings of WQI presented an increasing trend from upstream toward downstream in the Maroon River. The findings of the linear regression analysis showed no significant correlation between WQI scores with pH and SO4 2− concentrations even though the relationship is weak. These results suggest that pH and SO4 2− concentrations could be the secondary driving parameters behind the variations in WQI scores. It can be inferred that the Maroon River water is appropriate for irrigation based on Na% and SAR. However, it also exhibits high EC. Therefore, for mitigating the adverse impacts of polluted water authors recommend multidimensional management practices such as transferable discharge permit programs in the study area.

This study evaluates the impact of anthropogenic activities on the Shahrood River using water physico-chemical variables and macroinvertebrates data sets obtained over a period of 12 months between February 2012 and February 2013 at 8 sampling sites. Biotic indices i.e. FBI and BMWP based on macroinvertebrates and physico-chemical indices (MPI, HPI and NSF-WQI) were employed to evaluate the water quality status in connection with natural- and human-induced pressures. Based on physico-chemical indices, water quality was categorized as low polluted level and it is suitable for drinking purposes. The water quality based on biotic indices was related to the anthropic activities; a clear deterioration of the water quality was observed from upstream to downstream sites. The water quality along the river changed from very good (class I; reference sites) to good (class II; midstream sites) and turned into moderate (class III) and poor (class IV) quality (downstream sites). These findings indicate that biotic indices are more powerful indicators in assessing water quality than physico-chemical indices. Allocapnia, Glossosoma and Hesperoperla were exclusively related to least disturbed sites, and Naididae, Orthocladiinae and Ecdyonurus were found in sites showing notable degradation. Our results recommended that the use of macroinvertebrates could be employed as a cost-effective tool for biomonitoring and controlling of polluted riverine ecosystems in the Middle East. Finally, the results from this study may be useful not only for developing countries, but also for any organization struggling to use macroinvertebrate based indices with restricted financial resources and knowledge.

Aim This contribution reports the first regional occurrence of Pleurosira laevis in the Masuleh River, Iran and additionally describes the pattern of occurrence along the Masuleh River and among four substrate types. The aim of this study was to assess the effects of substrate type and physical and chemical variables on distribution of centric diatom P. laevis. Methods At each station, triplicate samples were collected from 4 substrata. Epilithic (assemblages on rock), epidendric (assemblages on wood), epipsammic (assemblages on sand), and epipelic (assemblages on mud) diatom and water quality sampling was done four times at 5 stations. Physical and chemical variables including total nitrate, total phosphate, silicate, Fe2+, EC, and pH were also determined. Samples preserved in 2% for formalin solution and transferred to the laboratory, boiled with acid (HNO3: H2SO4; 2:1), centrifuged, identified, and counted. Cluster analysis was performed to indicate the main differences and similarities in diatom abundance amongst substrates sampled and amongst sampling stations. Results The highest (12.54 ± 1.54) and lowest (0.74 ± 0.10) abundance was obtained from wooden and muddy substrates at stations S5 and S4, respectively. The highest abundance was observed in the wooden substrate among all of sampling stations where showed significant differences (P < 0.05) with the other substrates. The hierarchical clustering based on relative abundance of P. laevis distinguished two clusters amongst the four substrate types. Rougher and more stable substrates (wood, sand, and stone) clearly separated from smooth and unstable substrates (mud). Based on relative abundance of P. laevis on rougher substrates, epidendric and epipsammic species had the highest similarity. Results of Pearson correlation showed that relative abundance of P. laevis had a significant correlation with EC, TN, TP, and Fe2+ concentrations (P < 0.05) whilst no significant correlation was observed with pH, temperature, and SiO2 concentration (P > 0.05). Conclusion We conclude that wood substrata can be substituted for one another during field surveys. Results from this study demonstrate that the type and roughness of the substrate both influence the attachment of P. laevis and its subsequent growth conditions. Resumo: Objetivo Este trabalho relata a primeira ocorrência regional de Pleurosira laevis no rio Masuleh (Irã) e adicionalmente descreve o seu padrão de ocorrência ao longo do rio e em quatro tipos de substrato. O objetivo deste trabalho foi avaliar os efeitos do tipo de substrato e as variáveis físicas e químicas na distribuição da diatomácea cêntrica P. laveis. Métodos Em cada estação, amostras em triplicara foram coletadas em quatro substratos. Diatomáceas epifíticas (assembléias sobre rochas), epidendricas (assembléias em troncos), episâmicas (assembléias em areia) e epipélicas (assembléias em lodo) e amostras da qualidade de água foram obtidas quatro vezes em cinco estações. Variáveis físicas e químicas incluindo nitrato total, fosfato total, silicatos, Fe2+, CE, e pH também foram determinadas. As amostras foram preservadas em solução de formalina 2% e transferidas para o laboratório, fervidas em ácido (HNO3: H2SO4; 2:1), centrifugadas, identificadas e contadas. Uma análise de Cluster foi aplicada para indicar as principais diferenças e similaridades na abundância de diatomáceas entre substratos e entre estações de amostragem. Resultados A maior (12,54 ± 1,54) e a menor (0,74 ± 0,10) abundância foi obtida a partir de substratos de troncos e lodo nas estações S5 e S4, respectivamente. Entre todas as estações de amostragem a maior abundância foi observada no substrato de troncos, com diferenças significativas (P 0,05) . Conclusão Nós concluímos que o substrato de tronco pode ser substituído por um outro durante o levantamento de campo. Os resultados deste estudo demonstram que o tipo e a rugosidade do substrato influencia a fixação de P. laevis e as suas condições de crescimento subsequentes.