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Activating permanganate with reductants has gained increasing attention recently for efficient organic contaminants abatement via reactive intermediate Mn species. However, few studies have been conducted to explore the role of pyrophosphate (PP), a typical complexing agent for intermediate Mn species, in activated permanganate systems. In this study, taking sulfamethoxazole (SMX) as a probe compound, the influences of PP on SMX degradation by permanganate/thiosulfate and permanganate/hydroxylamine were extensively studied. It was found that both thiosulfate and hydroxylamine were able to activate permanganate for oxidation of SMX in the absence of PP. However, upon the introduction of PP, opposite effects were observed in the two systems where PP further improved the activation of permanganate by thiosulfate but dampened the performance of permanganate/hydroxylamine markedly. For permanganate/hydroxylamine system, MnO2 was determined to be the only reactive oxidative species accounting for SMX degradation in the absence of PP, and its generation could be completely inhibited by PP. While in permanganate/thiosulfate system, both Mn(V) and MnO2 were responsible for SMX oxidation, and the introduction of PP could strengthen the oxidative ability of Mn(V). These results could shed some insights on the suitability of applying PP to explore the kinetics and mechanisms of manganese involved redox reactions. Practitioner points: Both Na2S2O3 and NH2OH·HCl can activate KMnO4 for SMX removal without PP.MnO2 is the reactive oxidative species involved in KMnO4/NH2OH·HCl system.Mn(V) and MnO2 account for the SMX oxidation by KMnO4/Na2S2O3 system.PP could inhibit the formation of MnO2 but enhance the oxidative ability of Mn(V). [ABSTRACT FROM AUTHOR]

Abstract Adverse effects of sulfonamide antibiotics (SAs) include growth inhibition and antioxidant activation which showed trade-off effects. Yet, the influence of food availability on such effects have not been thoroughly investigated. Caenorhabditis elegans were exposed to four SAs at high and low food availabilities which were represented by the optical densities of bacteria at 600 nm. The nematode feeding, growth and antioxidants including superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) were determined. Results showed that the control nematodes at low food availability had less growth and greater antioxidant responses than the nematodes at high food availability. In SA exposure, the nematode growth in the presence of food (at both high and low food availability) was less than that in its absence, supporting the role of food as an exposure pathway. The nematode growth at low food availability showed significantly greater inhibition than at high food availability (p < 0.05). The nematode antioxidants showed stimulations, and CAT had the greatest stimulation. Moreover, the stimulation on CAT at low food availability were significantly higher than those at high food availability (p < 0.05). That is to say, SA exposure at low food availability further biased the trade-off effects towards more energy investment in antioxidant with less in growth. Further studies on the expression levels of CAT encoding genes demonstrated that cells in intestines were the main antioxidant response sites, which further supported the contributions of food to the observed toxicities. Highlights • In controls, low food availability caused trade-off between growth and antioxidants. • Sulfonamide exposure at low food availability biased trade-off toward antioxidants. • Sulfonamide exposure with food inhibited growth more than without food. • Sulfonamides stimulated intestinal catalase at high and low food availability. [ABSTRACT FROM AUTHOR]

Plastic particles have been proven to be abundant in the aquatic environment, raising concerns about their potential toxic effects. In the present study, we determined the bioaccumulation potential of bisphenol A (BPA) in adult zebrafish ( Danio rerio ) in the absence and presence of nano-sized plastic particles (nanoplastics, NPPs). Results show that BPA can accumulate in the viscera, gill, head and muscle of zebrafish with 85, 43, 20, and 3 μg/g ww after 1 d exposure. NPPs were also found to accumulate in different tissues of the fish. Relative equilibrium was reached after 1 d exposure in different tissues with 39 to 636 mg/kg ww . Co-exposure of NPPs and BPA led to a 2.2 and 2.6-fold significant increment of BPA uptake in the head and viscera, if compared with BPA alone treatment after 3 d exposure. As such, we further investigated several neurotoxic biomarker alterations in the fish head. It was found that either BPA or NPPs can cause myelin basic protein (MBP)/gene up-regulation in the central nervous system (CNS); meanwhile, both contaminants exhibited significant inhibition of acetylcholinesterase (AChE) activity, which is a well-known representative biomarker for neurotoxicity. Moreover, for the co-exposure treatment, biomarkers of myeline and tubulin protein/gene expressions, dopamine content, and the mRNA expression of mesencephalic astrocyte derived neurotrophic factor (MANF) were all significantly up-regulated, suggesting that an enhanced neurotoxic effects in both CNS and dopaminergic system occurred. However, AChE activity was no more inhibited in the co-exposure treatment, which implies that solely AChE measurement may not be sufficient to identify neurotoxic effects in the cholinergic system. Overall, the present study demonstrates that the presence of NPPs can increase BPA bioavailability and cause neurotoxicity in adult zebrafish. [ABSTRACT FROM AUTHOR]

• Research advances (2018-2022) in health threats of light pollution are reviewed. • Effects of artificial light at night and blue light are emphasized. • Links between light pollution and highly concerned health effects are uncovered. • Toxicological mechanism of disrupting circadian rhythm is highlighted. • Efforts on regulating light pollution are discussed. The prevalence of artificial lights not only improves the lighting conditions for modern society, but also poses kinds of health threats to human health. Although there are regulations and standards concerning light pollution, few of them are based on the potential contribution of improper lighting to diseases. Therefore, a better understanding of the health threats induced by light pollution may promote risk assessment and better regulation of artificial lights, thereby a healthy lighting environment. This review is based on a careful collection of the latest papers from 2018 to 2022 about the health threats of light pollution, both epidemiologically and experimentally. In addition to summing up the novel associations of light pollution with obesity, mental disorders, cancer, etc., we highlight the toxicological mechanism of light pollution via circadian disruption, since light pollution directly interferes with the natural light-dark cycles, and damages the circadian photoentrainment of organisms. And by reviewing the alternations of clock genes and disturbance of melatonin homeostasis induced by artificial lights, we aim to excavate the profound impacts of light pollution based on accumulating studies, thus providing perspectives for future research and guiding relevant regulations and standards. [Display omitted] [ABSTRACT FROM AUTHOR]

The potential transfer of fullerene aqueous suspension (nC 60 ) associated contaminants in vivo is one of the most significant and currently not well-understood environmental risks. In this study, the carrier function of nC 60 for ibuprofen (IBU) was examined through whole-body and tissue distribution determination of nC 60 and IBU in Cyprinus carpio . The results showed that the presence of nC 60 only slightly increased the whole-body burden of IBU, because the amount of soluble IBU far exceeds that of nC 60 associated form of IBU; while the presence of nC 60 activated the catalase activity and enhanced the lipid peroxidation in the liver, suggesting an obviously induced oxidative damage to fish. With the presence of nC 60 , the uptake of IBU in both gill and digestive tract tissues increased obviously: the uptake of IBU in the gill was mainly from the desorption of nC 60 associated IBU, and that in the digestive tract was both from nC 60 associated IBU and soluble IBU. On the contrary, the nC 60 reduced IBU uptake in the brain, probably due to the high accumulation of nC 60 which blocked the blood brain barrier. Moreover, there was no significant increase in the muscle, which implies that the soluble form should be the main source of IBU accumulation in the muscle. The carrier function of nC 60 observed in the present study indicates the potential transportation of other contaminants and the subsequently enhanced environmental risks. Capsule Fullerene aqueous suspension functioned as a carrier to alter the tissue distribution of ibuprofen in Cyprinus carpio . [ABSTRACT FROM AUTHOR]

The antagonism between selenium (Se) and mercury (Hg) has been widely recognized, however, the protective role of Se against methylmercury (MeHg) induced immunotoxicity and the underlying mechanism is still unclear. In the current study, MeHg exposure (0.01 mM via drinking water) significantly inhibited the lymphoproliferation and NK cells functions of the female Balb/c mice, while dietary Se supplementation (as Se-rich yeast) partly or fully recovered the observed immunotoxicity, indicating the protective role of Se against MeHg-induced immune suppression in mice. Besides, MeHg exposure promoted the generation of the reactive oxygen species (ROS), reduced the levels of nonenzymic and enzymic antioxidants in target organs, while dietary Se administration significantly diminished the MeHg-induced oxidative stress and subsequent cellular dysfunctions (lipid peroxidation and protein oxidation). Two possible mechanisms of Se’s protective effects were further revealed. Firstly, the reduction of mercury concentrations (less than 25%, modulated by Se supplementation) in the target organs might contribute, but not fully explain the alleviated immune suppression. Secondly and more importantly, Se could help to maintain/or elevate the activities of several key antioxidants, therefore protect the immune cells against MeHg-induced oxidative damage. [ABSTRACT FROM AUTHOR]

Antibiotics have been identified as obesogens contributing to the prevalence of obesity. Moreover, their environmental toxicity shows sex dependence, which might also explain the sex-dependent obesity observed. Yet, the direct evidence for such a connection and the underlying mechanisms remain to be explored. In this study, the effects of tetracycline, which is a representative antibiotic found in both environmental and food samples, on Drosophila melanogaster were studied with consideration of both sex and circadian rhythms (represented by the eclosion rhythm). Results showed that in morning-eclosed adults, tetracycline significantly stimulated the body weight of females (AM females) at 0.1, 1.0, 10.0 and 100.0 µg/L, while tetracycline only stimulated the body weight of males (AM males) at 1.0 µg/L. In the afternoon-eclosed adults, tetracycline significantly stimulated the body weight of females (PM females) at 0.1, 1.0 and 100.0 µg/L, while it showed more significant stimulation in males (PM males) at all concentrations. Notably, the stimulation levels were the greatest in PM males among all the adults. The results showed the clear sex dependence of the obesogenic effects, which was diminished by dysrhythmia. Further biochemical assays and clustering analysis suggested that the sex- and rhythm-dependent obesogenic effects resulted from the bias toward lipogenesis against lipolysis. Moreover, they were closely related to the preference for the energy storage forms of lactate and glucose and also to the presence of excessive insulin, with the involvement of glucolipid metabolism. Such relationships indicated potential bridges between the obesogenic effects of pollutants and other diseases, e.g., cancer and diabetes. [Display omitted] [ABSTRACT FROM AUTHOR]

The authors investigated the uptake and depuration of fullerene aqueous suspensions (nC60) in 2 aquatic organisms: Daphnia magna and zebrafish. The effects of humic acid were examined to elucidate its possible mechanisms in the aquatic environment. The uptake was concentration-dependent in both organisms, and the maximum uptake concentration of nC60 in Daphnia (2268 ± 158 mg/kg) was approximately 1 order of magnitude higher than that in zebrafish (222 ± 30 mg/kg) because of the larger gut volume ratio to the mass of Daphnia or its high uptake efficiency. Humic acid reduced the uptake of nC60 in Daphnia and zebrafish as a result of the size effect and the polarity alternation of nC60. The depuration patterns were rapid for Daphnia and slow for zebrafish, and the differences were most likely the result of different water exchange frequencies between organisms. The remaining nC60 percentages were approximately 20% for Daphnia and 30% for zebrafish after 48-h depuration, suggesting that a large nC60 burden still existed for both aquatic organisms and that there is a need for further studies on the potential for trophic transfer. Environ Toxicol Chem 2014;33:1090-1097. © 2014 SETAC [ABSTRACT FROM AUTHOR]

Abstract: The rapid increase in nanotechnology has led to growing concerns on environmental effects and health risks of nanoparticles (NPs). Many studies investigated the adsorption of toxic pollutants on NPs; however, the interaction between heavy metals and natural organic matter (NOM) coated metal oxide NPs was scarcely studied. In this study, using humic acid (HA) as model NOM, the adsorption of Cd(II) on humic acid coated titanium dioxide (HA–TiO2) NPs was investigated. Solution parameters such as pH and salinity were investigated to exploit the mechanisms. Our results demonstrated that the adsorption isotherms of Cd(II) to both TiO2 and HA–TiO2 complied well with Freundlich model. qe values increased with pH increase, mainly due to electrostatic attraction, whereas qe values increased initially and then decreased at 100mmolL−1 with salinity increase, mainly due to complexation and electrostatic effects. It is noteworthy that an overall trend of higher Cd(II) adsorption was observed on HA–TiO2 compared to that on TiO2, implying that HA coating might modify bioavailability of heavy metals in aquatic environment. The possible adsorption mechanisms in views of electrostatic interactions and covalent effects were interpreted, and the X-ray photoelectron spectroscopy (XPS) results also verified the possible mechanisms. [Copyright &y& Elsevier]

Abstract: Pentachlorophenol (PCP), a probable human carcinogen, has been heavily used as an aseptic and a biocide throughout the world, and is widely present in the environment. Recent survey in Germany revealed that the average PCP amount in the urine of general German populations was 1.04μg/L while the peak concentration could reach up to 19.1μg/L. PCP was reported to cause DNA damage, but whether it can be involved in inducing point mutations in genome is unknown. To determine the genotoxicity of PCP on vertebrate, we first performed acute toxicity test on zebrafish for the effect of PCP exposure. The LC50 values of zebrafish exposed to PCP at 24, 48, 72 and 96h were determined to be 0.196, 0.130, 0.130 and 0.130mg/L, respectively. We then treated zebrafish with PCP for 10 days at 0 (control), 0.5, 5 and 50μg/L, respectively, to determine whether PCP could be involved in inducing point mutations. Employing denaturing high-performance liquid chromatography analysis and DNA sequencing, we demonstrated that exposure of PCP to zebrafish at a concentration as low as 5μg/L for 10 days elevates point mutation rate in p53 gene in liver cells. This is the first direct evidence revealing that PCP can elevate point mutation rate in the vertebrate genomes. The result implies PCP might be involved in carcinogenesis by elevating point mutation rate in the somatic genomes. [Copyright &y& Elsevier]

Four chlorobenzenes (chlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, p-chloro-methylbenzene) were administrated to the crucian carps (Carassius auratus) by peritoneal injections in the laboratory for 30 days. Serum testosterone and 17β-estradiol concentrations were detected using radioimmunology assay (RIA), and the activities of two hepatic microsome enzymes, glutathione s-transferase (GST) and UDP-glucuronosyltransferase (UDPGT), were measured using the modified methods as described by Habig and Owens. Results showed that the four chlorobenzenes caused significant increases in serum testosterone concentration in the crucian carps (P<0.05) compared to the controls, but they caused no significant effect on 17β-estradiol level. All test chemicals caused a change in hepatic GST activity in crucian carps, with significant increases in enzyme activity (P<0.05). Chlorobenzene, 1,3-dichlorobenzene and p-chloro-methylbenzene resulted in a marked inhibition to UDPGT activity in crucian carp (P<0.05) except 1,4-dichlorobenzene. The changes in hepatic microsome enzyme activities may have resulted in the alterations of serum sex steroids levels in the crucian carps. The results indicated that these four chlorobenzenes may result in the changes of endocrine functions and may affect the reproductive success of this and other species. [Copyright &y& Elsevier]

Freshwater quality criteria of 2,4,6-trichlorophenol (2,4,6-TCP) were developed with particular reference to the aquatic biota in China, and based on USEPA’s guidelines. Acute toxicity tests were performed on nine different domestic species indigenous to China to determine 48 h LC50 and 96 h LC50 values for 2,4,6-TCP. In addition, 21 d survival–reproduction test with Daphnia magna, 30 d embryo-larval test with Carassius auratus, 60 d fry-juvenile test with Ctenopharyngodon idellus, 30 d early life stage test with Bufo bufo gargarizans and 96 h growth inhibition test with Scenedesmus obliqaus were also conducted to estimate lower chronic limit and upper chronic limit values. The final acute value (FAV) was 2.01 mg/l 2,4,6-TCP. Acute-to-chronic ratios ranged from 5.01 to 12.2. The final chronic value (FCV) and the final plant value (FPV) of 2,4,6-TCP were 0.226 and 2.24 mg/l respectively. Based on FAV, FCV and FPV for 2,4,6-TCP, a criteria maximum concentration of 1.01 mg/l and a criterion continuous concentration of 0.226 mg/l were derived. The results of this study provide useful data for deriving national or local water quality criteria for 2,4,6-TCP based on aquatic biota in China. [Copyright &y& Elsevier]

• TMA+ exposure significantly inhibited the swimming activities of larval zebrafish. • Swimming path angle is the most sensitive endpoint in response to TMA+ exposure. • Neurobehavior endpoints of larvae were significantly related with oxidative stress. • The calculated 96 h-LC 50 of TMA+ was lower for zebrafish juveniles than larvae. • TMA+ evoked greater inhibitions on multi-biomarkers of juveniles than larvae. Tetramethylammonium hydroxide (TMAH) is an important compound that utilized and released by the rapidly expanding semiconductor industry, which could hardly be removed by the conventional wastewater treatment techniques. As a cholinergic agonist, the tetramethylammonium ion (TMA+) has been reported to induce toxicity to muscular and respiratory systems of mammals and human, however the toxicity on aquatic biota remains poorly known. We investigated the neurotoxic effects of TMA+ exposure on zebrafish, based on neurobehavior tests and a series of biomarkers. Significant inhibitions on the swimming distance of zebrafish larvae were observed when the exposure level exceeded 50 mg/L, and significant alterations on swimming path angles (straight and deflective movements) occurred even at 10 mg/L. The tested neurobehavioral endpoints of zebrafish larvae were significantly positively correlated with reactive oxygen species (ROS) and malondialdehyde (MDA), significantly negatively related with the activities of antioxidant enzymes, but not significantly correlated with the level of acetylcholinesterase (AChE). Such relationship indicates that the observed neurotoxic effects on swimming behavior of zebrafish larvae is mainly driven by oxidative stress, rather than the alterations of neurotransmitter. At the highest exposure concentration (200 mg/L), TMA+ evoked more severe toxicity on zebrafish juveniles, showing significantly stronger elevation on the MDA activity, and greater inhibitions on the activities of antioxidant enzymes and AChE, suggesting juveniles were more susceptible to TMA+ exposure than larval zebrafish. [Display omitted] [ABSTRACT FROM AUTHOR]

• Removal kinetics of 4-NP was globally fitted with a mixed-order model. • Humic acid at high concentrations suppressed the removal of 4-NP. • Fe2+ addition increased 4-NP removal rate and decreased the duration of lag period. • Fe2+ addition mitigated the effects of HA by favoring 4-NP removal and HA separation. • Enrichment of contaminants on ZVI is the key for Fe2+ to improve electron efficiency. In this study, Fe2+ addition was employed to overcome the negative effects of humic acid (HA) on contaminant removal by zerovalent iron (ZVI), and its feasibility to improve electron efficiency of ZVI was also tested. HA at high concentrations suppressed the removal of 4-nitrophenol (4-NP) by ZVI, while the addition of 0.25–1.0 mM Fe2+ could greatly mitigate this inhibitory effect and enhance 4-NP reduction. Specifically, with a mixed-order model, global fitting results showed that the addition of Fe2+ increased the rate constant from 0.124 × 10−2–0.219 × 10−2 mM/min to 0.227 × 10−2–0.417 × 10−2 mM/min and shortened lag period from 19.7–47.9 min to 8.0–15.2 min for 4-NP removal. The mechanistic investigation revealed this trend could be explained by the following aspects: i) Fe2+ can facilitate the generation of Fe(II)-containing oxides, which can act as an electron mediator or direct electron donor for 4-NP reduction; ii) the presence of Fe2+ could lead to aggregation of HA particles and accordingly reduced its coverage on ZVI surface. But the results of respike experiments indicate that Fe2+ addition did not show remarkable effect on the electron efficiency of 4-NP by ZVI, which should be associated with that Fe2+ was not able to favor the enrichment of 4-NP on ZVI surface. [ABSTRACT FROM AUTHOR]

[Display omitted] • Water-borne erythromycin (ERY) increased triglycerides with inhibition on lipolysis. • Dietary ERY increased triglycerides with lipolysis-inhibition and lipogenesis-stimulation. • ERY's effects involved insulin and nhr-49 signaling pathways. • ERY disturbed bacterial colonization in intestines and intestinal barrier permeabilities. • ERY affected fatty acid composition (especially SCFAs) in bacteria and nematodes. As emerging pollutants, antibiotics were widely detected in water bodies and dietary sources. Recently, their obesogenic effects raised serious concerns. So far, it remained unclear whether their obesogenic effects would be influenced by water- and diet-borne exposure routes. In present study, Caenorhabditis elegans , nematodes free-living in air–water interface and feeding on bacteria, were exposed to water- and diet-borne erythromycin antibiotic (ERY). The statuses of the bacterial food, inactivated or alive, were also considered to explore their influences on the effects. Results showed that both water- and diet-borne ERY significantly stimulated body width and triglyceride contents. Moreover, diet-borne ERY's stimulation on the triglyceride levels was greater with alive bacteria than with inactivated bacteria. Biochemical analysis showed that water-borne ERY inhibited the activities of enzymes like adipose triglyceride lipase (ATGL) in fatty acid β-oxidation. Meanwhile, diet-borne ERY inhibited the activities of acyl-CoA synthetase (ACS) and carnitine palmitoyl transferase (CPT) in lipolysis, while it stimulated the activities of fatty acid synthase (FAS) in lipogenesis. Gene expression analysis demonstrated that water-borne ERY with alive bacteria significantly upregulated the expressions of daf-2 , daf-16 and nhr-49 , without significant influences in other settings. Further investigation demonstrated that ERY interfered with bacterial colonization in the intestine and the permeability of the intestinal barrier. Moreover, ERY decreased total long-chained fatty acids (LCFAs) in bacteria and nematodes, while it decreased total short-chained fatty acids (SCFAs) in bacteria but increased them in nematodes. Collectively, the present study demonstrated the differences between water- and diet-borne ERY's obesogenic effects, and highlighted the involvement of insulin and nhr-49 signaling pathways, SCFAs metabolism and also the interaction between intestinal bacteria and the host. [ABSTRACT FROM AUTHOR]

Abstract Influences on lipid metabolism and multi-generational obesogenic effects raised new concerns on lipophilic pollutants (e.g., lindane). Yet, the mechanisms remained unanswered. The present study exposed Caenorhabditis elegans to lindane for 4 consecutive generations (F0 to F3) at 1.0 ng/L, and measured effects in the directly exposed generations (F0 to F3), indirectly exposed ones (T1 and T1′) and un-exposed ones (T3 and T3′). Lindane stimulated fat storages in all generations. At the biochemical level, lindane stimulated both acetyl-CoA carboxylase (ACC) and carnitine palmitoyl-transferases (CPT) in F0, T1 and T2, while inhibited them in F3, T1′ and T3′, demonstrating the balance between fatty acid synthesis and its depletion toward fat accumulation over generations. Moreover, lindane caused different effects on insulin among generations. It inhibited insulin in F0 and F3 and exhibited consistent effects on the expression changes of daf-2 , sgk-1 and daf-16 genes in insulin-like signal pathway. Lindane also inhibited insulin in T1 and T3 but exhibited consistent effects on the expression changes of daf-2 , akt-1 and daf-16. Different roles of sgk-1 and akt-1 indicated the response strategies from tolerance (F0 and F3) to avoidance (T1 and T3). Lindane stimulated insulin in T1′ and T3′ and exhibited consistent effects on expression changes of daf-2 , sgk-1 and daf-16 genes that were similar in F0 and F3. Highlights • Multigenerational obesogenic effects of lindane were studied on C. elegans. • Lindane stimulated fat storages in F0, F3, T1, T3, T1′ and T3’. • Fat storage stimulation was due to greater fatty acid synthesis than its oxidation. • Lindane inhibited insulin in F0, F3, T1 and T3, but stimulated them in T1′ and T3’. • Insulin changes were consistent with expressions of daf-2 , sgk-1 / akt-1 and daf-16. [ABSTRACT FROM AUTHOR]

The developmental neurotoxicity caused by environmental pollutants has received great concern; however, there were still barely known about the underlying toxic mechanisms, especially the influence of varieties of regulatory factors such as microRNA (miRNA). A representative flame retardant, 2,2′,4,4′-tetrabromodiphenyl ether (BDE47), was found to disrupt zebrafish development in visual perception and bone formation in previous study, thus here we investigated its effects on miRNA expression profiling of 6 days post fertilization (dpf) zebrafish larvae by deep sequencing. To overcome the shortage of zebrafish miRNA annotation, multiple data processing approaches, especially constructed network based on the interactions between miRNAs and enrichment terms, were adopted and helped us acquire several validated zebrafish miRNAs and two novel miRNAs in BDE47-induced effects, and identify corresponding biological processes of the miRNAs. Among them, miR-735 was supposed to play essential roles in larval sensory development according to analysis results. Our study also provided an effective strategy for analyzing biological effects on non-mammalian miRNAs with limited basic information. [ABSTRACT FROM AUTHOR]

Earlier studies showed that toxicities of excessive metals lasted over generations. Yet, these studies mainly employed one-generation exposure, and the effects of multigenerational challenges need further studies. Presently, Caenorhabditis elegans were exposed to cadmium, copper, lead and zinc for four consecutive generations (G1 to G4) at environmental concentrations. The feeding, growth, initial reproduction, superoxide dismutase (SOD) and catalase (CAT) were determined. All data were represented in the percentage of that in control (POC), and POC in the control was normalized to 100%. In G1 and G2, the POC values in feeding, growth and initial reproduction were generally within 10% of the control (100%), indicating non-significant effects. The POC values in SOD and CAT were significantly higher than 100%, showing stimulatory effects. In G3 and G4, the POC values in feeding, growth and initial reproduction were significantly lower than 100%, showing inhibitory effects which were more severe in G4 than in G3. Meanwhile, SOD and CAT continuously showed stimulatory effects, and the stimulatory effects on SOD increased from G1 to G4. The effects with multigenerational challenges were different from those in one-generation exposure. The effects in later generations demonstrated the importance of multigenerational challenges in judging long-term influences of metals. [ABSTRACT FROM AUTHOR]

A highly sensitive method based on solid-phase extraction and ultra high performance liquid chromatography with electrospray tandem mass spectrometry has been developed for simultaneous determination of five iodinated X-ray contrast media in environmental water samples. Various solid-phase extraction cartridges have been evaluated and a combination of LiChrolute EN and ENVI-Carb solid phase extraction cartridges was selected for sample enrichment. The method was comprehensively validated on ground water, tap water, surface water, drinking water, and waste water by the conventional procedures: linearity, method detection limits, accuracy and precision, matrix effects. Good linearity ( R2 > 0.999), low detection limits (0.4-8.1 ng/L), satisfactory recoveries (55.1-109.5%) and precision (0.8-10.0% for intra-day precisions and 0.6-16.5% for inter-day precisions) were obtained for all the target compounds. Iopamidol, iohexol, and diatrizoate in some matrices were affected by matrix effects, which were slightly eased by using the isotope-labeled internal standard. The developed method was successfully applied for real samples collected in Shanghai, China, with detected concentrations up to 2200 ± 200 and 9000 ± 1000 ng/L for iohexol and iopamidol, respectively. [ABSTRACT FROM AUTHOR]

A novel adsorbent, magnetic nanoparticle (γ-Fe2O3)-coated zeolite (MNCZ), was prepared for the removal of arsenic (As) ions from aqueous solution. The influence of different sorption parameters, that is, contact time, acidic reaction (pH) and initial arsenic concentration were studied using batch equilibrium techniques. The results obtained showed that the MNCZ was effective for the removal of As from aqueous solution, and the percentage removal of As could reach over 95.6% at a pH value of 2.5 within 15 min. Moreover, the removal of As depended on the initial concentration of As. For the regeneration of MNCZ material, 0.1 M NaOH was suitable for the desorption of As (70% after 15 min), and the regenerated material showed an adsorption capacity of 93.95% within five cycles. We concluded that MNCZ presents a reusable adsorbent for a fast, convenient and highly efficient removal of As from aqueous solution. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Formation of haloacetamides function of DON/DOC, SUVA254 and bromide. [•] DON/DOC may act as an indicator of HAcAm yields during chlorination. [•] More formation during chloramination in low-SUVA waters with no bromide. [•] More formation of dihalogenated species than tri- or mono-halogenated species. [•] Bromine incorporation increased with increasing bromide with either disinfectant. [Copyright &y& Elsevier]

The present study proposed a QSAR model to predict joint effects at non-equitoxic ratios for binary mixtures containing reactive toxicants, cyanogenic compounds and aldehydes. Toxicity of single and binary mixtures was measured by quantifying the decrease in light emission from the Photobacterium phosphoreum for 15 min. The joint effects of binary mixtures (TUsum) can thus be obtained. The results showed that the relationships between toxic ratios of the individual chemicals and their joint effects can be described by normal distribution function. Based on normal distribution equations, the joint effects of binary mixtures at non-equitoxic ratios (TUn:msum) can be predicted quantitatively using the joint effects at equitoxic ratios (TU1:1sum). Combined with a QSAR model of TU1:1sum in our previous work, a novel QSAR model can be proposed to predict the joint effects of mixtures at non-equitoxic ratios (TUn:msum). The proposed model has been validated using additional mixtures other than the one used for the development of the model. Predicted and observed results were similar (p>0.05). This study provides an approach to the prediction of joint effects for binary mixtures at non-equitoxic ratios. [ABSTRACT FROM AUTHOR]

Abstract: The haloacetamides (HAcAms) are disinfection by-products (DBPs) in drinking water which are currently receiving increased scientific attention due to their elevated toxicity relative to regulated disinfection by-products. A simultaneous determination method of 13 HAcAms, combining solid-phase extraction (SPE) enrichment, liquid chromatographic (LC) separation, and triple quadrupole mass spectrometry (tqMS) detection with atmospheric pressure chemical ionization (APCI) using selective reaction monitoring in positive mode, was developed to measure HAcAms, including chlorinated, brominated, and iodinated analogs. Ammonium chloride and Oasis HLB were selected as the dechlorinating reagent and polymeric SPE sorbent of HAcAm samples. The used tqMS apparatus showed higher sensitivity for the studied HAcAms in the APCI mode than electrospray ionization. 13 HAcAms were separated by LC in 9.0min, and the detection limits ranged from 7.6 to 19.7ng/L. The SPE-LC/tqMS method was successfully applied to quantify 13 HAcAms in drinking water samples for the first time, and first indentified tribromoacetamide and chloroiodoacetamide as DBPs in drinking water. [Copyright &y& Elsevier]

Abstract: Pilot-scale tests were performed to reduce the formation of several nitrogenous and carbonaceous disinfection by-products (DBPs) with an integrated ozone and biological activated carbon (O3–BAC) treatment process following conventional water treatment processes (coagulation–sedimentation–filtration). Relative to the conventional processes alone, O3–BAC significantly improved the removal of turbidity, dissolved organic carbon, UV254, and dissolved organic nitrogen from 98–99%, 58–72%, 31–53%, 16–93% and 35–74%, respectively, and enhanced the removal efficiency of the precursors for the measured DBPs. The conventional process was almost ineffective in removing the precursors of trichloronitromethane (TCNM) and dichloroacetamide (DCAcAm). Ozonation could not substantially reduce the formation of DCAcAm, and actually increased the formation potential of TCNM; it chemically altered the molecular structures of the precursors and increased the biodegradability of N-containing organic compounds. Consequently, the subsequent BAC filtration substantially reduced the formation of the both TCNM and DCAcAm, thus highlighting a synergistic effect of O3 and BAC. Additionally, O3–BAC was effective at controlling the formation of the total organic halogen, which can be considered as an indicator of the formation of unidentified DBPs. [Copyright &y& Elsevier]

Environmental contaminants are usually encountered as mixtures, and many of these mixtures yield synergistic or antagonistic effects attributable to an intracellular chemical reaction that pose a potential threat on ecological systems. However, how atomic charges of individual chemicals determine their intracellular chemical reactions, and then determine the joint effects for mixtures containing reactive toxicants, is not well understood. To address this issue, the joint effects between cyanogenic toxicants and aldehydes on Photobacterium phosphoreum were observed in the present study. Their toxicological joint effects differed from one another. This difference is inherently related to the two atomic charges of the individual chemicals: the oxygen charge of -CHO ( Oaldehyde toxicant) in aldehyde toxicants and the carbon-atom charge of a carbon chain in the cyanogenic toxicant ( Ccyanogenic toxicant). Based on these two atomic charges, the following QSAR (quantitative structure-activity relationship) model was proposed: When ( Oaldehyde toxicant − Ccyanogenic toxicant) > −0.125, the joint effect of equitoxic binary mixtures at median inhibition (TU, the sum of toxic units) can be calculated as TU = 1.00 ± 0.20; when ( Oaldehyde toxicant − Ccyanogenic toxicant) ≤ −0.125, the joint effect can be calculated using ${\rm TU} = - 27.6 \times O_{{\rm aldehyde}\;{\rm toxicant}} - 5.22 \times C_{{\rm cyanogenic}\;{\rm toxicant}} - 6.97$ ( n = 40, r = 0.887, SE = 0.195, F = 140, p < 0.001, q2Loo = 0.748; SE is the standard error of the regression, F is the F test statistic). The result provides insight into the relationship between the atomic charges and the joint effects for mixtures containing cyanogenic toxicants and aldehydes. This demonstrates that the essence of the joint effects resulting from intracellular chemical reactions depends on the atomic charges of individual chemicals. The present study provides a possible approach for the development of a QSAR model for mixtures containing reactive toxicants based on the atomic charges. Environ. Toxicol. Chem. 2012;31:270-278. © 2011 SETAC [ABSTRACT FROM AUTHOR]

Abstract: Perfluorinated carboxylic acids (PFCAs) have wide industrial applications because of their unique physicochemical characteristics. However, data on the toxicity of much of this chemical class is lacking, particularly with regard to mixture toxicity. In this study, the toxicity of individual PFCAs and their mixtures to Photobacterium phosphoreum were observed. There was a tendency of increasing toxicity from C3 to C14 PFCA and a tendency of decreasing toxicity from C14 to C18 PFCA because of “the maximum tolerance of the cell membrane”. Using the equivalent log K OW (octanol–water partition coefficient) and log K SD (C18-Empore™ disks/water partition coefficient), two linear quantitative structure–activity relationship (QSAR) models were formulated. This indicated both K SD and K OW can describe the hydrophobicity of a single chemical. However, for the PFCA mixtures, K MD is the more reasonable parameter than K owmix to describe the hydrophobicity because only the equivalent log K MD could be used to predict the mixture toxicity. [Copyright &y& Elsevier]

Abstract: Water samples were collected from 19 sampling sites along the Huangpu River in June and December 2009. The occurrence, distribution and seasonal variation of 22 antibiotics, including four tetracyclines, three chloramphenicols, two macrolides, six fluoroquinolones, six sulfonamides and trimethoprim were investigated. It was found that all 19 sampling sites were contaminated by antibiotics. Four antibiotics (sulfamerazine, norfloxacin, fleroxacin and sarafloxacin) were not detected. The detection frequencies of the other 18 antibiotics were in the range of 5.3–100%. The median concentrations of the detected antibiotics ranged from quantification limits to 36.71ngL−1 (tetracycline) in June and to 313.44ngL−1 (sulfamethazine) in December. The number of detected antibiotics and the overall antibiotic concentrations were higher in December than in June due to the different river flow conditions. Different dominant antibiotics were observed for each group of antibiotics between June and December. Higher total concentrations of veterinary antibiotics such as tetracyclines were observed in suburban sampling sites than in unban sites, indicating the role of livestock and agricultural activities as an important source of antibiotic contamination. [ABSTRACT FROM AUTHOR]

Short-chained perfluorobutane sulfonate (PFBS, four-carbon) and perfluorohexane sulfonate (PFHxS, six-carbon) are widely employed to substitute long-chained per- and poly-fluoroalkyl substances (PFASs). Recent studies showed the potential persistence of PFBS and PFHxS, and also reported their correlation with obesity. However, the long-term outcome and underlying mechanisms remained poorly understood. Presently, the effects of PFBS and PFHxS were studied on C. elegans with multi- and trans -generational experiments. The multi-generational effects were measured in continuous four generational exposure (i.e., F1 to F4). Results showed that PFBS did not stimulate the fat content in F1 but in F4 with continuous but different disturbances on the lipid metabolism and the insulin and insulin-like (IIS) pathway. PFHxS stimulated the fat content in F1 and F4 with similar disturbances on the lipid metabolism and IIS pathway. The trans -generational results showed that the effects of PFBS and PFHxS on the lipid metabolism and IIS pathway were not totally recovered in the offspring of F1 (i.e., T1-T3) and F4 (i.e., T1′-T3′) which were not continuously exposed. PFHxS showed a common pattern to up-regulate daf-7 in both multi- and trans -generational effects. The long-term consequences of the short-chained PFASs substitutes should be concerned and epigenetic regulations should be considered in future mechanism studies. [Display omitted] • PFBS stimulated the fat content not in F1 but in F4 generation. • PFBS disturbed lipid metabolism and IIS pathway differently from F1 to F4. • PFHS stimulated the fat content in F1 and F4 generation. • PFHS had similar disturbances on lipid metabolism and IIS pathway from F1 and F4. • PFHS commonly up-regulated daf-7 in both multi- and trans -generational effects. [ABSTRACT FROM AUTHOR]

The extensive utilization of antibiotics in the pharmaceutical therapies and agricultural husbandry has led to the worldwide pollution in environments. In this study the photolysis behaviors of tetracycline (TC) and toxicity of its degradation products were investigated. The results showed that TC photolysis followed first-order kinetics. The photolysis rate was found to be dependent on the initial TC concentration and increasing TC concentration from 10 to 40mgl−1 led to the decrease of the photolysis rate constant from 0.0045min−1 to 0.0014min−1. TC photolysis was highly pH-dependent and strongly enhanced at high pH value. Markedly elevated TC photolysis was also observed in the presence of nitrate and dissolved organic matter. Upon irradiation for 300min, only 15% reduction of total organic carbon (TOC) occurred in spite of quick conversion of 73% of TC, suggesting that a majority of TC transformed into intermediate products without complete mineralization. The intermediate products from TC photolysis were analyzed using high-performance liquid chromatography–electrospray ionisation-mass spectrometry (HPLC–ESI-MS) and the main photolysis products of TC were proposed. The toxicity of the photolysis compounds was evaluated using luminescent bacterium, and the results revealed that the toxicity increased with irradiation, indicative of a higher adversity risk of the degradation products of TC on bacteria upon photolysis. [Copyright &y& Elsevier]

Abstract: Mesoporous carbon, CMK-3, was prepared using hexagonal SBA-15 mesoporous silica as the template and the adsorption of nonylphenol ethoxylates (NPE) onto CMK-3 was investigated. The adsorption process was well described using pseudo-second-order kinetics. At initial NPE concentrations of 107 and 530 mg l−1, the adsorption rate constants were found to be and , indicating that a higher initial concentration or adsorption amount resulted in a lower adsorption rate. NPE adsorption onto CMK-3 fitted a Langmuir–Freundlich model and the maximum amounts of NPE absorbed at 15, 25, and 35 °C were 923, 720, and 463 mg g−1, suggesting an elevated adsorption capacity of CMK-3 for NPE with decreased adsorption temperature. In addition, increasing adsorption temperature led to the change of the adsorption model from the Langmuir–Freundlich to the Langmuir model. N2 adsorption results showed that the adsorption of NPE led to a decrease in the mesopore volume of CMK-3. However, the pore width of NPE-loaded CMK-3 was found to be identical to that of CMK-3. [Copyright &y& Elsevier]

• 13 drinking water treatment plants in 11 European and Asian countries were assessed • 115 organic micropollutants were detected in raw water and drinking water • Removal efficiency of organic micropollutants varied greatly between plants • 208 features were detected using suspect screening and three confirmed with standards • Removal efficiency was correlated for target compounds and suspect features There is growing worry that drinking water can be affected by contaminants of emerging concern (CECs), potentially threatening human health. In this study, a wide range of CECs (n = 177), including pharmaceuticals, pesticides, perfluoroalkyl substances (PFASs) and other compounds, were analysed in raw water and in drinking water collected from drinking water treatment plants (DWTPs) in Europe and Asia (n = 13). The impact of human activities was reflected in large numbers of compounds detected (n = 115) and high variation in concentrations in the raw water (range 15-7995 ng L−1 for ∑ 177 CECs). The variation was less pronounced in drinking water, with total concentration ranging from 35 to 919 ng L−1. Treatment efficiency was on average 65 ± 28%, with wide variation between different DWTPs. The DWTP with the highest ∑CEC concentrations in raw water had the most efficient treatment procedure (average treatment efficiency 89%), whereas the DWTP with the lowest ∑ 177 CEC concentration in the raw water had the lowest average treatment efficiency (2.3%). Suspect screening was performed for 500 compounds ranked high as chemicals of concern for drinking water, using a prioritisation tool (SusTool). Overall, 208 features of interest were discovered and three were confirmed with reference standards. There was co-variation between removal efficiency in DWTPs for the target compounds and the suspected features detected using suspect screening, implying that removal of known contaminants can be used to predict overall removal of potential CECs for drinking water production. Our results can be of high value for DWTPs around the globe in their planning for future treatment strategies to meet the increasing concern about human exposure to unknown CECs present in their drinking water. [ABSTRACT FROM AUTHOR]

Metal pollution in drinking water source has been under scrutiny as it seriously affects human health. This work examined 12 dissolved metals in the surface and overlying water of the Xiangjiang River, an important drinking water source in southern China, and characterized their distribution, identified their possible sources, assessed their toxicity load, and determined their potential ecological and health risk. No significant difference was found in the metal concentration between surface and overlying water. The average metal concentration fell in the order of Mg > Mn > Ba > Fe > Zn > As > Sb > Ni > Cd > V > Cr > Co, and all was lower than the safety threshold in the drinking water guideline of China. Anthropogenic activities were found to be the main source of metals from correlation analysis, principal component analysis (PCA), and cluster analysis (CA). According to the total heavy metal toxicity load (HMTL), 98.20%, 71.54%, 68.88%, and 7.97% of As, Cd, Sb, and Mn should be removed from the surface water to ensure safety. Most water samples from the surveyed area were found to have high ecological risk as was measured by the ecological risk index (RI). Health risk assessment showed that children are more susceptible than adults to the non-carcinogenic risk of dissolved metals, and the potential carcinogenic risk (CR) of As and Cd should be addressed. The results provide guidance for controlling the metal pollution of the Xiangjiang River and improving its quality as a drinking water source. [ABSTRACT FROM AUTHOR]

Metal pollution in drinking water source has been under scrutiny as it seriously affects human health. This work examined 12 dissolved metals in the surface and overlying water of the Xiangjiang River, an important drinking water source in southern China, and characterized their distribution, identified their possible sources, assessed their toxicity load, and determined their potential ecological and health risk. No significant difference was found in the metal concentration between surface and overlying water. The average metal concentration fell in the order of Mg > Mn > Ba > Fe > Zn > As > Sb > Ni > Cd > V > Cr > Co, and all was lower than the safety threshold in the drinking water guideline of China. Anthropogenic activities were found to be the main source of metals from correlation analysis, principal component analysis (PCA), and cluster analysis (CA). According to the total heavy metal toxicity load (HMTL), 98.20%, 71.54%, 68.88%, and 7.97% of As, Cd, Sb, and Mn should be removed from the surface water to ensure safety. Most water samples from the surveyed area were found to have high ecological risk as was measured by the ecological risk index (RI). Health risk assessment showed that children are more susceptible than adults to the non-carcinogenic risk of dissolved metals, and the potential carcinogenic risk (CR) of As and Cd should be addressed. The results provide guidance for controlling the metal pollution of the Xiangjiang River and improving its quality as a drinking water source. [ABSTRACT FROM AUTHOR]

• The reactive oxidative species (ROS) was studied in the Fe(III)/sulfite process. • The correlation of Fe(III)/Fe(II) with ROS generation was studied in this process. • Carbamazepine (CBZ) could be degraded at different conditions in this process. • SO 4 − and HO were the primary and secondary ROS, respectively, in this process. • In-situ generated Fe(II) played critical role in ROS generation in this process. Since the reactive species during the sulfite activation by Fe(III) (Fe(III)/sulfite process) had not been directly determined and the role of in-situ generated Fe(II) was overlooked, this study evaluated the oxidation performance of the Fe(III)/sulfite process, identified the reactive species, and investigated the role of in-situ generated Fe(II) in this process. The results demonstrated that carbamazepine (CBZ) could be degraded at different sulfite concentrations. Compared to the single-dosing mode, sulfite applied with multiple-dosing mode was beneficial to CBZ removal in this process when the same amount of sulfite was dosed. Fe(II) was rapidly generated and then decayed in this process, which were consistent with the trends of CBZ degradation and sulfite consumption. Electron paramagnetic resonance and scavenging experiments showed that SO 4 − was a major oxidant, while HO also played a significant role in CBZ degradation in this process. The tert-butyl alcohol assay indicated that the generation and re-oxidation of Fe(II) was accompanied with the generation of reactive species. Besides sulfite dosage, CBZ degradation was also affected by initial pH, Fe(III) dosage, and CBZ concentration. Cl− showed little inhibition on CBZ degradation while humic acid inhibited CBZ degradation in this process. This study advances the application of this oxidation system. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) and mesoplastics are able to sorb harmful substances and often contain additives, e.g., endocrine disrupting chemicals (EDCs), that can cause adverse effects to organisms. The present study aims to determine EDC concentrations and their endocrine activities in leachates of field-collected marine MPs and mesoplastics under stress conditions that are known to occur during the plastic life cycle. Estrogens were the dominant EDCs on plastic particles and were either concentrated from the surrounding water or originated from plastic manufacturing. Bisphenol A had the highest detection frequency (75%) with an average concentration of 475 ± 882 μg/kg, followed by bisphenol S, octylphenol and nonylphenol. Moreover, smaller marine MPs leached greater quantities of EDCs because the sorption from surrounding seawater is more efficient for smaller particles. It was found that normal life stresses such as microwaving (MW) and autoclaving (AC) can decrease EDC concentrations, but solar irradiation (solar) can increase EDC concentrations in leachates. Even though organisms with higher metabolic ability exhibited greater estrogenic effects, the comprehensive toxicity of plastic leachates after common life treatments was still limited (below the EC 10 value) if 0.1% is taken as the EDC uptake from plastic. In future studies, the accurate contribution of plastic bound EDCs needs to be further explored, and the monitoring of MPs and mesoplastics in the human diet remains important because the concentrations of these plastics may change in the future. Unlabelled Image • Estrogens are dominant EDCs on marine micro- and mesoplastics. • Smaller microplastics released more EDCs and had higher detection frequencies. • Microwaving and autoclaving decreased but solar irradiation increased EDCs. • Micro-/mesoplastic-containing seafood cooking led to negligible estrogenic effects. [ABSTRACT FROM AUTHOR]

Specific ion effects on the aggregation behavior of a reference aquatic natural organic matter (NOM), Suwannee River NOM (SRNOM), were investigated using kinetic, titration, calorimetric, and surface tension methods. Monovalent cations induced structural compacting of SRNOM, but not its aggregation. Their ability to induce structural compacting follows the order: Cs+ > Rb+ > K+ > Na+ > Li+. Divalent cations except Mg2+ can readily induce SRNOM aggregation. Their critical coagulation concentrations (CCC) follow the order: CCC Sr > CCC Ca > CCC Ba. Electrokinetic, titration, and calorimetric data suggest that monovalent cations have weak interactions with SRNOM, while divalent cations strongly interact with SRNOM. Overall, the cation specificity in aggregation is determined by cation-NOM interactions and their ability to modulate surface tension. Specific ion effects of monovalent cations correlate to their hydration free energy, while that of divalent cations correlate to the ratio of the hydration entropy of cation to the enthalpy change of cation-NOM interactions. The cation specificity is consistent with the extended Derjaguin-Landau-Verwey-Overbeek theory, and the intermolecular interaction energy is dominated by the Lewis acid-base interactions. Our results suggest that specific cations should be targeted to predict or manipulate intermolecular interactions of aquatic NOM in natural and engineered settings. [ABSTRACT FROM AUTHOR]

• The neurotoxicity of CPs were assessed using zebrafish larvae-based behavioral tests. • The chlorine content of CPs possessed more influence than carbon chain length. • The coordination of three indicators enhanced the test's sensitivity and resolution. Increasing concern has arisen regarding ubiquitous environmental distribution and potential ecological and health risks of chlorinated paraffins (CPs), especially short chain congeners. Four commercial CP products with different carbon chain lengths and chlorine contents were employed to investigate and compare the possible neurotoxic effects on zebrafish larvae at 5 days post fertilization using behavioral tests, including locomotion, path angle, and two-fish social interaction. The high-chlorinated short-chain CP-70 product resulted in the strongest effects in all three tests, while the low-chlorinated long-chain CP-42 product was on the other end of the spectrum. The consequences of the chain length of two CP-52 products could be clearly distinguished by the tests. Although exposure to the two products both caused inhibition in the locomotion test, they resulted in different kinds of effects in the path angle and interaction tests. Our results suggested, as evidenced by the sensitivity and resolution of the behavioral tests, that the influence of the chain length and chlorine content of CPs could be well characterized and that chlorine content consistently showed a more significant impact than chain length. The health threats of long-chain CPs could also not be overlooked when they contained relatively high chlorine contents. [ABSTRACT FROM AUTHOR]

Nanoplastics (NPs) and microplastics (MPs) could act as potential carriers for pharmaceuticals and personal care products (PPCPs) and alter the bioavailability in the aquatic environment. The effects of NPs and MPs of polystyrene (PS) and polyethylene (PE) on the availability of five PPCPs including carbamazepine, bisphenol A, estrone, triclocarban and 4-tert-octylphenol were investigated by negligible depletion solid- phase microextraction (nd-SPME). The freely dissolved concentrations of PPCPs decreased with the increasing concentrations of NPs/MPs. The overall order of the sorption coefficients (log K NP / log K MP) of PPCPs was as follows: 100 nm PS > 50 nm PS > 1 µm PS > 100 µm PS > 100 µm PE. Sorption of PPCPs by NPs was generally 1–2 orders of magnitude stronger than to MPs. The log K NP / log K MP values (3.16–5.21) increased with the log K OW (2.45–5.28) of PPCPs, however, linear correlation was only observed between log K MP and log K OW. The particle size, specific surface area, aggregation state as well as hydrophobicity played an important role in the sorption. Coexistence of fulic acid (FA) with NPs inhibited the sorption due to the fouling of FA on NPs. This study suggests that sorption of PPCPs to MPs/NPs could reduce bioavailability of PPCPs in the aquatic environment. [Display omitted] • Nd-SPME was developed for PPCP availability study at environmental concentrations. • Sorption of PPCPs to NPs was 1–2 orders of magnitude stronger than to MPs. • The order of the sorption: 100 nm PS > 50 nm PS > 1 µm PS > 100 µm PS > 100 µm PE. • Sorption of PPCPs to NPs are differed from MPs due to specified aggregation of NPs. • Coexistence with fulic acid inhibited the sorption of PPCPs to NPs. [ABSTRACT FROM AUTHOR]

Benzotriazole ultraviolet stabilizers (BUVSs), used extensively in both consumer and industrial products, are emerging pollutants of concern, of which, 2-(3, 5-di- tert -amyl-2-hydroxyphenyl) benzotriazole (UV-328) is currently listed under the Stockholm Convention. BUVSs have been detected widely in environmental and biological matrices; thus, they are accessible to humans via environmental exposure and dietary intake. Due to their bioaccumulation and toxicity, the requirements for environmental human health risk assessment led to the development of sensitive analytical methods for BUVSs. In this review, the analytical methods for BUVSs and metabolites in environmental and biological samples are summarized, mainly focusing on pretreatment techniques including liquid extraction, solid-phase extraction and gel permeation chromatography, as well as instrumental analysis with chromatography-mass spectrometry. In addition, the overall occurrence of BUVSs in environmental matrices and organisms is summarized, to discuss possible human exposures. Finally, the metabolism, toxicity, and human health impacts of BUVSs are overviewed. [Display omitted] • GPC combined with SPE are the mostly used clean-up techniques for complex samples. • Trace BUVS analysis in environment is almost exclusively achieved by GC/MS or LC/MS. • BUVSs are extensively present in the environment and accumulated in organisms. • BUVSs can be metabolized by human CYP450 and mainly metabolized by the liver. • Endocrine disruption, liver toxicity, and immunotoxicity are highlighted. [ABSTRACT FROM AUTHOR]