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1.
Environ Res ; 173: 246-254, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30928855

RESUMO

Persistent organic pollutants (POPs) are found in high concentrations in the Artic. Polar bears (Ursus maritimus) are one of the most exposed mammals in the Arctic and are thereby vulnerable to reproductive disruption. The aim of this study was to investigate male polar bear reproduction based on a detailed evaluation of testis histology and to assess possible effects of environmental chemicals on male polar bear reproduction. Reproductive groups that were identified based on histology were as follows: actively reproductive (REP), non-reproductive either with degenerated testes (DEG), undeveloped seminiferous tubules (UND), or morphology in-transition (INT). Categorization into these groups was supported by significant differences in testis and baculum measurements among REP, DEG, and UND, as well as differences in the area and diameter of seminiferous tubules among REP, DEG, and UND. These results show that it is possible to identify the reproductive stage in polar bears even if capture date and or age is lacking. Based on testis morphology we suggest that adult male polar bears from East Greenland have active spermatogenesis in February to June, and inactive degenerated testes in August to January. January to February was the main period of reproductive transition, characterised by a shift between inactive and active spermatogenesis. Baculum and testis size measurements decreased significantly with increasing concentrations of the chlordane metabolite oxychlordane, suggesting a potential impact on male reproductive success. Half of the investigated polar bears in REP group displayed signs of disorganization of the spermatogenesis which might be a sign of disrupted reproduction. However, no correlations with levels of the investigated POPs were detected. Reproductive organ measurements in polar bears differed significantly between REP and DEG groups, which cannot be explained by age, and therefore should be considered when investigating the effect of POPs on male reproduction.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais , Testículo , Ursidae , Animais , Regiões Árticas , Groenlândia , Masculino , Estações do Ano
2.
Environ Res ; 162: 74-80, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29287182

RESUMO

We investigated skull size (condylobasal length; CBL) and bone mineral density (BMD) in polar bears (Ursus maritimus) from East Greenland (n = 307) and Svalbard (n = 173) sampled during the period 1892-2015 in East Greenland and 1964-2004 at Svalbard. Adult males from East Greenland showed a continuous decrease in BMD from 1892 to 2015 (linear regression: p < 0.01) indicating that adult male skulls collected in the early pre-pollution period had the highest BMD. A similar decrease in BMD over time was not found for the East Greenland adult females. However, there was a non-significant trend that the skull size of adult East Greenland females was negatively correlated with collection year 1892-2015 (linear regression: p = 0.06). No temporal change was found for BMD or skull size in Svalbard polar bears (ANOVA: all p > 0.05) nor was there any significant difference in BMD between Svalbard and East Greenland subpopulations. Skull size was larger in polar bears from Svalbard than from East Greenland (two-way ANOVA: p = 0.003). T-scores reflecting risk of osteoporosis showed that adult males from both East Greenland and Svalbard are at risk of developing osteopenia. Finally, when correcting for age and sex, BMD in East Greenland polar bears increased with increasing concentrations of persistent organic pollutants (POPs) i.e. ΣPCB (polychlorinated biphenyls), ΣHCH (hexachlorohexane), HCB (hexachlorobenzene) and ΣPBDE (polybrominated diphenyl ethers) while skull size increased with ΣHCH concentrations all in the period 1999-2014 (multiple linear regression: all p < 0.05, n = 175). The results suggest that environmental changes over time, including exposure to POPs, may affect bone density and size of polar bears.


Assuntos
Densidade Óssea , Poluentes Ambientais , Crânio , Ursidae , Animais , Monitoramento Ambiental , Poluentes Ambientais/toxicidade , Feminino , Groenlândia , Masculino , Compostos Orgânicos/toxicidade , Crânio/anatomia & histologia , Svalbard , Ursidae/anatomia & histologia , Ursidae/fisiologia
3.
J Hazard Mater ; 466: 133543, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38262318

RESUMO

The prevalence of organophosphate esters (OPEs) in the global environment is increasing, which aligns with the decline in the usage of polybrominated diphenyl ethers (PBDEs). PBDEs, a category of flame retardants, were banned and classified as persistent organic pollutants (POPs) through the Stockholm Convention due to their toxic and persistent properties. Despite a lack of comprehensive understanding of their ecological and health consequences, OPEs were adopted as replacements for PBDEs. This research aims to offer a comparative assessment of PBDEs and OPEs in various domains, specifically focusing on their persistence, bioaccumulation, and toxicity (PBT) properties. This study explored physicochemical properties (such as molecular weight, octanol-water partition coefficient, octanol-air partition coefficient, Henry's law constant, and vapor pressures), environmental behaviors, global concentrations in environmental matrices (air, water, and soil), toxicities, bioaccumulation, and trophic transfer mechanisms of both groups of compounds. Based on the comparison and analysis of environmental and toxicological data, we evaluate whether OPEs represent another instance of regrettable substitution and global contamination as much as PBDEs. Our findings indicate that the physical and chemical characteristics, environmental behaviors, and global concentrations of PBDEs and OPEs, are similar and overlap in many instances. Notably, OPE concentrations have even surged by orders of several magnitude compared to PBDEs in certain pristine regions like the Arctic and Antarctic, implying long-range transport. In many instances, air and water concentrations of OPEs have been increased than PBDEs. While the bioaccumulation factors (BAFs) of PBDEs (ranging from 4.8 to 7.5) are slightly elevated compared to OPEs (-0.5 to 5.36) in aquatic environments, both groups of compounds exhibit BAF values beyond the threshold of 5000 L/kg (log10 BAF > 3.7). Similarly, the trophic magnification factors (TMFs) for PBDEs (ranging from 0.39 to 4.44) slightly surpass those for OPEs (ranging from 1.06 to 3.5) in all cases. Metabolic biotransformation rates (LogKM) and hydrophobicity are potentially major factors deciding their trophic magnification potential. However, many compounds of PBDEs and OPEs show TMF values higher than 1, indicating biomagnification potential. Collectively, all data suggest that PBDEs and OPEs have the potential to bioaccumulate and transfer through the food chain. OPEs and PBDEs present a myriad of toxicity endpoints, with notable overlaps encompassing reproductive issues, oxidative stress, developmental defects, liver dysfunction, DNA damage, neurological toxicity, reproductive anomalies, carcinogenic effects, and behavior changes. Based on our investigation and comparative analysis, we conclude that substituting PBDEs with OPEs is regrettable based on PBT properties, underscoring the urgency for policy reforms and effective management strategies. Addressing this predicament before an exacerbation of global contamination is imperative.


Assuntos
Retardadores de Chama , Éteres Difenil Halogenados , Éteres Difenil Halogenados/toxicidade , Éteres Difenil Halogenados/análise , Monitoramento Ambiental , Organofosfatos/análise , Água/análise , Retardadores de Chama/toxicidade , Retardadores de Chama/análise , Octanóis , Ésteres/toxicidade
4.
Environ Sci Pollut Res Int ; 31(19): 28341-28352, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38532220

RESUMO

Antioxidants are ubiquitous in various environmental samples, leading to increasing concern regarding their potential risk to environments or humans. However, there is dearth of information regarding the environmental fate of antioxidants and unknown/unexpected antioxidants in the environment. Here, we established a compound database (CDB) containing 320 current-used antioxidants by collecting the chemicals from EPA's functional use database and published documents. Physical-chemical characteristics of these antioxidants were estimated, and 19 ones were considered as persistent and bioaccumulative (P&B) substances. This CDB was further coupled with high resolution mass spectrometry (HRMS) technique, which was employed for suspect screening of antioxidants in extracts of sediments (n = 88) collected from Taihu Lake basin. We screened 119 HRMS features that can match 135 chemical formulas in the CDB, and 20 out of them exhibited the detection frequencies ≥ 90%. The total concentrations of suspect antioxidants in sediments ranged from 6.41 to 830 ng/g dw. Statistical analysis demonstrated that concentrations of suspect antioxidants in Taihu Lake were statistically significantly lower than those in Shihu and Jiulihu Lake, but greater than those from other small lakes. Collectively, this study provided a CDB that could be helpful for further monitoring studies of antioxidant in the environments, and also provided the first evidence regarding the ubiquity of antioxidants in aquatic environment of Taihu Lake basin.


Assuntos
Antioxidantes , Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Espectrometria de Massas , Poluentes Químicos da Água , Lagos/química , China , Antioxidantes/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos
5.
Water Res ; 218: 118498, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35489155

RESUMO

Polychlorinated diphenyl sulfides (PCDPSs) represent an emerging group of constituents that are persistent, bioaccumulative and toxic (PBT) substances of great concern in terms of human health and ecological integrity. However, little is known about the occurrence, environmental behaviour and ecological risks of PCDPSs in lake environments. In this study, the concentrations of 21 PCDPSs were determined in surface water, suspended particulate matter (SPM), sediments, and 8 fish species from Chaohu Lake, China. Eighteen PCDPS congeners were prevalently detected in the samples, with concentrations ranging from 0.272-1.69 ng/L (water), 0.477-2.03 ng/g d.w. (SPM), 0.719-4.07 ng/g d.w. (sediment) and 0-0.131 ng/g w.w. (fish), respectively. Medium- and high-chlorinated PCDPSs in SPM and sediment were significantly higher than those in water samples. Increased PCDPS concentrations were found in higher trophic level fishes and those with a demersal habitat preference, indicating their bioaccumulation and biomagnification potential. The logBCFs, BSSAFs, and BSAFs of PCDPS congeners in fishes were determined to be 3.91-5.18, 0.0500-2.33, and 0.0360-4.94 L/kg, respectively. The organic carbon normalized partition coefficients (logKoc) of PCDPSs in surface water-SPM (4.61-5.54 L/g) and surface water-sediment (4.38-5.69 L/g) systems were determined, and it was found that highly chlorinated PCDPSs were more prone to migrate from water to sediment and SPM. The toxic equivalent (TEQ) values of PCDPSs in the samples (lower than 10-1 pg/g or pg/L) and daily intake via fish consumption (0.180-0.340 µg/kg/day) were estimated for humans, and cumulative risk quotients (RQs) after correction at ten sampling sites (0.065-0.66) were calculated for green algae. The findings elucidated the environmental behaviour of PCDPSs in Chaohu Lake.


Assuntos
Sedimentos Geológicos , Poluentes Químicos da Água , Animais , Bioacumulação , China , Monitoramento Ambiental , Peixes , Material Particulado , Sulfetos , Água , Poluentes Químicos da Água/análise
6.
Sci Total Environ ; 804: 150211, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34798742

RESUMO

Per- and poly-fluoroalkyl substances (PFAS) are a problematic group of chemicals used in various industrial and household products. They have been extensively detected in wastewater as a result of day-to-day product usage. Due to concerns about their safety, voluntary and regulatory action to limit the manufacture and use of some individual PFAS has occurred since the year 2000. The impact that this intervention has had on the use and potential exposure of Australians has not been measured. Wastewater serves as a powerful tool to assess the chemical use or consumption patterns of a population over time. We accessed a ten-year wastewater archiving program to conduct a temporal analysis of PFAS trends in an urban Australian population between the years 2010 and 2020. Results showed a decline in the concentrations for most PFAS, and a change in the PFAS profile from perfluorosulfonic acids and long-chain perfluorocarboxylic acids, to the short-chain perfluorocarboxylic acids and PFOS-replacement degradation products such as 5:3 FTCA. Intermittent pulses of PFAS that were significantly higher than 'background' levels (i.e., representing the PFAS input from primarily households) were observed, suggesting continuing industrial PFAS input within the wastewater catchment. This study highlights the long-term consequences of the diffuse use of persistent chemicals in products, and their ability to continue to enter the wastewater stream for decades.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Purificação da Água , Austrália , Fluorocarbonos/análise , Estudos Retrospectivos , Águas Residuárias
7.
Environ Toxicol Chem ; 41(1): 219-229, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807997

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are globally distributed and present in nearly every environmental compartment. Characterizing the chronic toxicity of individual PFAS compounds and mixtures is necessary because many have been reported to cause adverse health effects. To derive toxicity reference values (TRVs) and conduct ecotoxicological risk assessments (ERAs) of PFAS-contaminated ecosystems for wildlife, species-specific PFAS chronic toxicity values (CTVs) are needed. The present study quantified PFAS residues from liver and eggs of birds chronically exposed to perfluorohexanoic acid (PFHxA) or a mixture of perfluorooctane sulfonate (PFOS) and PFHxA that produced a no-observable-adverse-effect level (NOAEL) and/or a lowest-observable-adverse-effectlevel (LOAEL). The CTVs we present are lower than those previously reported for birds and should be considered in future regulatory evaluations. From the estimated species- and tissue-specific PFAS CTVs, we found that PFOS and perfluorohexane sulfonate (PFHxS) were more bioaccumulative than PFHxA in avian tissues, but PFHxA was more toxic to reproducing birds than either PFOS or a PFOS:PFHxS mixture. We further determined that avian toxicity was not necessarily additive with respect to PFAS mixtures, which could have implications for PFAS ERAs. The PFAS LOAEL CTVs can be used to predict reproductive and possible population-level adverse health effects in wild avian receptors. Environ Toxicol Chem 2022;41:219-229. © 2021 SETAC.


Assuntos
Ácidos Alcanossulfônicos , Colinus , Fluorocarbonos , Ácidos Alcanossulfônicos/toxicidade , Animais , Aves , Ecossistema , Fluorocarbonos/análise , Fluorocarbonos/toxicidade , Ácidos Sulfônicos
8.
Environ Toxicol Chem ; 40(9): 2394-2405, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34062012

RESUMO

Methods used to derive water quality regulations for persistent, bioaccumulative, and toxic substances (PBTs) in the United States have evolved substantially over the past 50 yr, leveraging current understandings and assumptions about the nature and magnitude of partitioning and accumulation of substances in water, sediments, and organisms. In the United States and across the world, environmental regulations continue to evolve into more refined water quality criteria protective of aquatic life and human health. The present review provides historical context on the establishment of aquatic life and human health water quality criteria in the United States by compiling information from regulatory agencies and peer-reviewed literature on methods used to characterize and quantify bioaccumulation of substances in aquatic organisms and humans. Primary data needs and assumptions for various methods, as well as their application in setting criteria by the US Environmental Protection Agency over the past half century, are highlighted. Our review offers an important retrospective on the data and methods used to derive water quality criteria for PBTs and provides commentary on the future of US criteria development. Environ Toxicol Chem 2021;40:2394-2405. © 2021 SETAC.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , Organismos Aquáticos , Bioacumulação , Humanos , Estudos Retrospectivos , Estados Unidos , Poluentes Químicos da Água/toxicidade
9.
Environ Pollut ; 271: 116363, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33385895

RESUMO

The concern about microplastic (a group of polymers) in the environment may cause us to overlook a more substantial problem: microplastics will fragment into nanoplastics. This fragmentation will lead to a high number of nanoplastics particles. Such nanoplastic can be taken up by cells, as opposed to microscale particles that are either not or to much less extend taken up. Fragmentation into nano will also release materials previously safely embedded in the polymer. We here present results from 25 OECD/ISO in vivo hazard tests, and beyond, e.g. extended exposure duration, with Enchytraeus crypticus, using pristine nano-scale materials (NMs) [CuO, Fe2O3, Organic Pigment, MWCNT], fragmented products (polymers) with these NMs embedded in the matrices (FP_NM), and fragmented polymers without NMs (FP) [covering the 4 major plastic types: Acrylic, Polyethylene, Polypropylene and Epoxy]. For example, MWCNTs induced a highly significant population decrease after extended period of 60 days, despite having no impact after 28 days' exposure, the standard OECD duration. We conclude, that the standard tests were not suitable to evaluate hazards of these plastic fragments, weathering/ageing of materials is recommended, and extension of test duration can add value to the testing of NMs. We must refocus the concern to testing with polymers (not only "plastics"), from micro-to nano-polymers, and from aquatic to terrestrial environments.


Assuntos
Oligoquetos , Poluentes Químicos da Água , Animais , Poluição Ambiental , Microplásticos , Plásticos , Polímeros , Poluentes Químicos da Água/análise
10.
Environ Toxicol Chem ; 40(10): 2657-2666, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34003500

RESUMO

Polychlorinated diphenyl sulfides (PCDPSs) have recently attracted increasing attention due to their potential adverse effects on human and ecosystem health. We present a review regarding their environmental occurrence, persistence, bioaccumulation, toxicity, and biotransformation. The existing literature demonstrates that PCDPSs are ubiquitous in various environmental matrices, are persistent in the environment, and have long-range transport potential. In addition, the high bioaccumulation potential of these emerging pollutants, especially the low chlorinated PCDPS congeners, has been confirmed based on both theoretical calculations and experimental investigations. Moreover, a spectrum of adverse effects, such as acute liver injury, retardation of development, reproductive disorders, and increased mortality have been widely reported in vertebrates. These adverse outcomes were associated with oxidative stress and activation of aryl hydrocarbon receptors. Given these findings, PCDPSs represent candidate persistent, bioaccumulative, and toxic substances and thus deserve further research to fully elucidate their environmental behavior and fate, and evaluate the risks to human and ecosystem health. Environ Toxicol Chem 2021;40:2657-2666. © 2021 SETAC.


Assuntos
Ecossistema , Sulfetos , Animais , Bioacumulação , Humanos , Receptores de Hidrocarboneto Arílico/metabolismo , Sulfetos/metabolismo , Sulfetos/toxicidade
11.
Environ Toxicol Chem ; 40(3): 899-909, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33210750

RESUMO

To further characterize avian toxicity to environmental levels of select per- and poly-fluoroalkyl substances (PFAS), we established species- and tissue-specific PFAS chronic toxicity values (CTVs) associated with a lowest-observable-adverse effect level (LOAEL) threshold previously established for northern bobwhite quail (Colinus virginianus) chronically orally exposed via drinking water to either perfluorooctane sulfonate (PFOS) or a simple PFAS mixture. Aided by advances in analytical techniques, the novel avian oral PFAS CTVs reported in the present study are lower than the previously reported toxicity reference values (TRVs) estimated for birds chronically exposed via feed. Thus, current avian PFOS TRVs may not be fully protective of wild avian populations at PFAS-impacted sites. Also, likely due to differences in bioavailability, bioaccessibility, and toxicokinetics among individual PFAS between oral exposure types, we found higher bioaccumulation factors in all assessed tissues from birds exposed via water versus feed. Thus, we propose that future characterization of chemical toxicity due to ingestion exposure initially include a full examination of all probable sources of oral exposure for the most accurate derivation of TRVs and a more complete picture of ecological risk. The avian PFAS LOAEL CTVs established in the present study can be modified with the use of uncertainty factors to derive site-specific avian TRVs for ecological risk assessment at PFAS-impacted sites. From differences observed in the behavior of PFOS when administered as either a single chemical or part of a binary mixture with perfluorohexane sulfonate (PFHxS), we verified that PFOS was absorbed and distributed differently when coadministered with PFHxS and that PFOS likely interacted with PFHxS differently among tissues, helping to explain the differences observed in avian toxicity between exposures. Environ Toxicol Chem 2021;40:899-909. © 2020 SETAC.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Ácidos Alcanossulfônicos/toxicidade , Animais , Aves , Fluorocarbonos/toxicidade
12.
Environ Toxicol Chem ; 39(2): 343-351, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31610611

RESUMO

Tissue distributions and body-size dependent and species-specific bioaccumulation of 12 organic ultraviolet absorbents (UVAs) were investigated in 9 species of wildlife freshwater fish from the Pearl River catchment, South China. The concentrations of the 12 UVAs were from 109 to 2320 ng/g lipid weight in the fish tissue samples. The UVAs 2-hydroxy-4-methoxybenzophenone (BP-3), octocrylene (OCR), UV531, and 5 benzotriazole UV stabilizers (UVP, UV329, UV234, UV328, and UV327) were detected in more than half of the fish tissue samples. The UVA UV531 showed an obvious potential for bioaccumulation in the wild freshwater fish, with an estimated bioaccumulation factor (log BAF) and a biota-sediment accumulation factor (BSAF) of 4.54 ± 0.55 and 4.88 ± 6.78, respectively. Generally, liver (989 ± 464 ng/g lipid wt) contained the highest level of UVAs, followed in decreasing order by belly fat (599 ± 318 ng/g lipid wt), swimming bladder (494 ± 282 ng/g lipid wt), dorsal muscle (470 ± 240 ng/g lipid wt), and egg (442 ± 238 ng/g lipid wt). The bioaccumulation of UVAs in the freshwater wild fish was species specific and compound dependent. Bottom-dwelling detritus-ingesting omnivorous fish contained obviously higher UVA concentrations, suggesting that detritus/sediment ingestion is a significant pathway for exposure of the wild freshwater fish to the UVAs. The UVAs UV531 and BP-3 demonstrated a potential for growth dilution. Metabolism might play a significant role in elimination of the UVAs in the fish tissues, with the highest rate of metabolism in the liver. The UVAs did not demonstrate obvious trophic magnification in the freshwater ecosystem of the Pearl River catchment. More research is warranted to elucidate maternal transfer of the UVAs. Environ Toxicol Chem 2020;39:343-351. © 2019 SETAC.


Assuntos
Bioacumulação , Monitoramento Ambiental/métodos , Peixes/metabolismo , Rios/química , Protetores Solares/análise , Poluentes Químicos da Água/análise , Animais , Animais Selvagens/metabolismo , Biota/efeitos dos fármacos , Tamanho Corporal , China , Ecossistema , Peixes/genética , Protetores Solares/metabolismo , Distribuição Tecidual , Poluentes Químicos da Água/metabolismo
13.
Mar Environ Res ; 161: 105063, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32738555

RESUMO

A previous investigation of our research team has demonstrated the suitability of using hepatic total tin (ΣSn) concentrations for evaluating dolphin exposure to organotins (OTs). The present study develops the previous technique into three different approaches that comprise data: (1) on hepatic ΣSn concentrations of 121 Guiana dolphins (Sotalia guianensis) from five different coastal areas (CAs): (2) on ΣSn, δ13C and δ15N for 40 dolphins from Rio de Janeiro state (RJ), including ten different delphinid species; as well as (3) on hepatic ΣSn concentrations and δ15N values on 31 individuals from five different fish species from Sepetiba Bay (SB, Rio de Janeiro-RJ, Brazil). Hepatic ΣSn concentrations of Guiana dolphins from Guanabara Bay (GB, RJ) were significantly higher than those found in other four CAs from S and SE Brazilian regions. Significant positive correlations were found between ΣSn concentrations and δ13C data in delphinid species, demonstrating a coast-ocean gradient in dolphin exposure to OTs in RJ state. Significant and positive correlations were observed between ΣSn concentrations and both δ15N and Trophic Position (TP) values of fish, as well as high values were found for Trophic Magnification Factor (TMF = 3.03) and Trophic Magnification Slope (TMS = 0.14), demonstrating OT biomagnification in SB ichthyofauna.


Assuntos
Golfinhos , Poluentes Químicos da Água , Animais , Bioacumulação , Brasil , Proteínas de Ligação a DNA , Monitoramento Ambiental , Peixes , Isótopos , Estanho , Poluentes Químicos da Água/análise
14.
Toxicol Rep ; 7: 995-1000, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32874922

RESUMO

Quantitative structure-activity relationship (QSAR) models have been applied to predict a variety of toxicity endpoints. Their performance needs to be validated, in a variety of cases, to increase their applicability to chemical regulation. Using the data set of substances of very high concern (SVHCs), the performance of QSAR models were evaluated to predict the persistence and bioaccumulation of PBT, and the carcinogenicity and mutagenicity of CMR. BIOWIN and Toxtree showed higher sensitivity than other QSAR models - the former for persistence and bioaccumulation, the latter for carcinogenicity. In terms of mutagenicity, the sensitivities of QSAR models were underestimated, Toxtree was more accurate and specific than lazy structure-activity relationships (LAZARs) and Computer Assisted Evaluation of industrial chemical Substances According to Regulations (CAESAR). Using the weight of evidence (WoE) approach, which integrates results of individual QSAR models, enhanced the sensitivity of each toxicity endpoint. On the basis of obtained results, in particular the prediction of persistence and bioaccumulation by KOWWIN, a conservative criterion is recommended of log Kow greater than 4.5 in K-REACH, without an upper limit. This study suggests that reliable production of toxicity data by QSAR models is facilitated by a better understanding of the performance of these models.

15.
Environ Pollut ; 253: 1-10, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31301531

RESUMO

Organic pollutants in the Arctic seas have been of concern to many researchers; however, the vast dynamic marine water poses challenges to their comprehensive monitoring within appropriate spatial and temporal scales in the Arctic. In this study, on-board passive sampling of organic pollutants using a self-developed device coupled with triolein-embedded cellulose acetate membranes (TECAMs) was performed during an Arctic cruise. The TECAM extracts were used for target analysis of organophosphorus flame retardants (PFRs), and non-target screening of persistent, bioaccumulative, and toxic (PBT) contaminants using two-dimensional gas chromatography with time-of-flight mass spectrometry (GC × GC-TOFMS). Sixteen chemicals were screened out as PBT contaminants from the 1500 features in the non-target analysis and further identified. Consequently, two chlorinated PFRs (tris(chloroisopropyl)phosphate and tris(1,3-dichloroisopropyl)phosphate) and four PBT contaminants (4-tert-butylphenol, 2-isopropylnaphthalene, 1,1,3-trimethyl-3-phenylindane, and 1-phenylnonan-1-one) were accurately quantified, with the temporally and spatially integrated concentrations ranging from 0.83 ng L-1 to 20.82 ng L-1 in the seawaters. Sources and transport of the contaminants were studied, and ocean current transport (West Spitsbergen Current, WSC) and local sources (human settlement, Arctic oil exploitation, and petroleum fuel emissions) were found to contribute to the presence of the different contaminants. Finally, annual transport fluxes of the contaminants from the North Atlantic to the Arctic Ocean by WSC were estimated, and the results indicate that their hazard to the Arctic should be concerned.


Assuntos
Monitoramento Ambiental/métodos , Retardadores de Chama/análise , Organofosfatos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Regiões Árticas , Poluentes Ambientais/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Svalbard
16.
Sci Total Environ ; 547: 9-16, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26780127

RESUMO

Plants can bioaccumulate triclosan and bond with microbes and sediments in constructed wetlands (CWs) as well. However, little is known regarding the species-specific removal mechanism of CWs components and the selection of suitable wetland plant species for triclosan disposal. In this work, the use of bioaccumulation factors (BAFs) and biota to sediment accumulation factors (BSAFs) for choosing the best triclosan removal plant species was studied in laboratory-scale CWs. By the end of the experiment, over 80% of triclosan was removed and a specie-effect distribution was revealed in CWs with emergent, submerged and floating plants. By mass balance calculation, negative correlation between triclosan concentration in plants and degradation process was observed. The significant correlations between Log BSAFs values and triclosan concentration in plants or degradation contribution made it possible and reasonable in wetland plants selection. Introductions on plant species were provided considering the target removal process or regulation method. This work provided new information on plant species selection in CWs for triclosan removal or its emergency remediation by using bioaccumulative factors.


Assuntos
Recuperação e Remediação Ambiental/métodos , Plantas/metabolismo , Triclosan/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Biodegradação Ambiental , Triclosan/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo
17.
J Colloid Interface Sci ; 447: 167-72, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25459219

RESUMO

Here, we report the formation of surface nanosheets by electropolymerization of original 3,4 propylenedioxythiophene (ProDOT) derivatives bearing both a short perfluorobutyl chain (C4F9) and a branched alkyl chain of various lengths in order to reduce the bioaccumulative potential of the obtained materials. The dimension of the nanosheets is dependent on the size of the branched alkyl chain. These nanostructures display parahygrophobic properties (apparent contact angle θ>θ(Y) for various liquid probes, where θ(Y) is the Young angle of the corresponding smooth surface) with an extremely high liquid adhesion. These properties are due to the presence of nanoporosity between the nanosheets, which favours the Cassie-Baxter state but with high adhesion due to an important contact between the nanosheets and the liquids. These results are extremely important also in a theoretical point of view in the aim to study surfaces with high contact angles and high adhesion. Such materials could also be used in water harvesting systems especially in hot environment.


Assuntos
Galvanoplastia/métodos , Flúor/química , Nanoestruturas/química , Tiofenos/química , Água/química , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Propriedades de Superfície , Termodinâmica
18.
Rev. chil. nutr ; 37(4): 493-496, dic. 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-583002

RESUMO

The current state of environmental pollution by persistent bio-accumulative and toxic substances (PBTS) in the Chilean food and population is practically unknown. This short communication aims to open the discussion on the need to assess the level of contamination of PBTS derived from foods consumed by the Chilean population considering diet as one of the main route of exposure.


El estado actual de la contaminación ambiental con Sustancias Persistentes Bioacumulables y Toxicas (PBTS) en los alimentos y población Chilena es prácticamente desconocida. Por este motivo esta comunicación corta tiene como objeto abrir la discusión sobre la necesidad de evaluar el nivel de contaminación por PBTS proveniente de los alimentos que consume la población Chilena, considerando a la dieta como una principal vía de exposición.


Assuntos
Bioacumulação/efeitos adversos , Contaminação de Alimentos/análise , Substâncias Tóxicas
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