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1.
Environ Monit Assess ; 192(6): 404, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472215

RESUMO

The St. Lawrence River, at Cornwall Ontario, has accumulated sediment contaminants, mainly mercury (Hg) and polychlorinated biphenyls (PCBs), from industrial point sources over many years. Although those sources are past, the river at Cornwall remains an Area of Concern (AOC). Because of remediation and other changes in the AOC, improved knowledge of contaminants in wild-fish and their putative links to health effects could help decision makers to better assess the AOC's state. Thus, we compared tissue concentrations of Hg, PCBs, morphometric measures of health, and biomarkers of exposure, metabolic-, and reproductive health in native brown bullhead (Ameiurus nebulosus) from the AOC to those of upstream reference fish. Linear discriminant analysis separated the adult fish of both sexes among upstream and downstream sites without misclassification. Burdens of total-Hg (all sites) and PCB toxic equivalents (downstream sites) exceeded the guidance for the protection of wildlife consumers. There were subtle effects of site on physiological variables, particularly in female fish. Total-Hg in tissue correlated negatively to plasma testosterone and 17ß-estradiol in female fish at Cornwall: moreover, concentrations of both hormones were lower within the AOC compared to reference site fish. A similar effect on vitellogenin, which was uncorrelated to E2/T at the downstream sites, indicated the potential for reproductive effects. Downstream fish also had altered thyroidal status (T3, TSH, and ratio of thyroid epithelial cell area to colloid area). Despite spatial and temporal variability of the endocrine-related responses, these subtle effects on fish health within the AOC warrant further study.


Assuntos
Ictaluridae , Mercúrio , Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Feminino , Masculino , Ontário
2.
Sci Total Environ ; 732: 139210, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32438180

RESUMO

Eggshell pigmentation has been assessed as an indicator of exposure to environmental pollutants in birds, but these studies have only used reflectance spectrophotometry to measure such pigmentation. The present study is the first one that measures eggshell pigments and pollutants in the same eggs to explore their use as biomarkers in birds. We have studied the concentration of organochlorine pesticides and polychlorinated biphenyls (PCBs) in the content of 97 deserted eggs of gull-billed terns (Gelochelidon nilotica) after the abandonment of the colony in Mesas de Asta (Cádiz, S Spain) in 2012. Eggshell thickness and stage of embryo development were studied together along with the concentrations of protoporphyrin IX and biliverdin in eggshells. p,p'-DDE concentrations were high when compared with other studies done with terns in the Mediterranean basin in the past. p,p'-DDE and PCB levels associated with reduced reproductive success were found in 5.1% and 2.1% of the eggs respectively. Eggshell index was largely affected by the embryo development stage, which highlights the need of knowing this information to avoid potential biases in the interpretation of results. The concentrations of protoporphyrin IX and biliverdin in the eggs of gull-billed terns were negatively associated with DDTs levels, which seems to confirm previous observations with phylogenetically related species.


Assuntos
Charadriiformes , Animais , Biomarcadores , Casca de Ovo , Poluentes Ambientais , Pigmentação , Bifenilos Policlorados , Espanha
3.
Chemosphere ; 253: 126630, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32278189

RESUMO

In this study, we have investigated biotransformation and oxidative stress responses in relation to tissue contaminant burden in the African sharptooth catfish (Clarias gariepinus) exposed to simulated leachate from a solid waste dumpsite in Calabar, Nigeria. Fish were exposed to simulated leachate, diluted to 0:0 (negative control), 1:10, 1:50, 1:100 and phenanthrene (a PAH: 50 µg/L used as a positive control) for 3, 7 and 14 days. Hepatic transcripts for cat, sod1, gpx1, gr, gst, cyp1a, cyp2d3, and cyp27 were analyzed by real-time PCR, while enzymatic assays for ethoxyresorufin O-deethylase (EROD), buthoxyresorufin O-deethylase (BROD), methoxyresorufin O-deethylase (MROD), pentoxyresorufin O-deethylase (PROD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), uridine diphospho-glucuronosyltransferase (UDPGT) and lipid peroxidase (LPO) were measured using standard methods. In addition, protein expression for CYP1A, CYP3A and metallotheionin (MT) were measured by immunoblotting. Fish muscle samples were analyzed for selected group of contaminants after 14 days exposure showing significantly high uptake of heavy metals (Cd, Hg and Pb), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), chlorophenols, organochlorine (OC) and organophosphate pesticides in exposed fish. We observed significant concentration- and time-specific increases in biotransformation and oxidative stress responses at transcript and functional (enzyme and protein) levels, that paralleled tissue contaminants bioaccumulation patterns, after exposure to the simulated leachates. Our results highlighted the potential environmental, wildlife and public health consequences from improper solid waste disposal. In addition, it also provides a scientific basis for local sensitization and inform legislative decisions and policy formulation towards sustainable environmental management of solid wastes in Nigeria and other developing countries.


Assuntos
Peixes-Gato/fisiologia , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/metabolismo , Animais , Biotransformação , Catalase/metabolismo , Peixes-Gato/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Glutationa Peroxidase , Glutationa Transferase/metabolismo , Metais Pesados/análise , Nigéria , Estresse Oxidativo , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Resíduos Sólidos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
4.
Chemosphere ; 253: 126651, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32283424

RESUMO

This study investigated the characteristics of dl-PCNs, PCDD/Fs and dl-PCBs emitted from two typical secondary copper metallurgical plants processing copper sludge equipped with different sets of air pollution control devices (APCDs). Results indicated that the emission factors of dl-PCNs and PCDD/Fs of plant A are 0.00775 and 1.09 µg TEQ/ton, respectively, which are remarkably lower than those of plant B (3.12, 181 and 25.5 µg TEQ/ton for dl-PCNs, PCDD/Fs and dl-PCBs, respectively). Dl-PCNs contributed 0.7-2.7% of total TEQ for flue gases and up to 2.6% of TEQ for ash samples. The TEQ concentration of dl-PCNs in fly ash individually exceeds the regulated level of 1 ng TEQ/g regulated by Taiwan EPA, indicating that emission and discharge of dl-PCNs should be regulated. The combination of semidry scrubber and activated carbon injection (ACI) + baghouse (BH) is effective for simultaneous removals of dl-PCNs and PCDD/Fs in plant A; while the combination of cyclone, secondary combustion chamber, ACI + BH and wet scrubber (WS) is not optimal for removing dl-PCNs, PCDD/Fs and dl-PCBs. Memory effect occurring within BH and WS is responsible for low removal efficiencies of these POPs in plant B. This study suggests appropriate APCDs for simultaneous removal of three POP groups and recommends the inclusion of dl-PCNs in emission standard.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Metalurgia , Cinza de Carvão/análise , Cobre/química , Dibenzofuranos/química , Dibenzofuranos Policlorados/análise , Gases/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Esgotos , Taiwan
5.
Mar Pollut Bull ; 153: 110979, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275536

RESUMO

Within Southern California, east Pacific green sea turtles (Chelonia mydas) forage year-round, taking advantage of diverse food resources, including seagrass, marine algae, and invertebrates. Assessing persistent organic pollutants (POP) in green turtle aggregations in the Seal Beach National Wildlife Refuge (SBNWR, n = 17) and San Diego Bay (SDB, n = 25) can help quantify contamination risks for these populations. Blood plasma was analyzed for polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs). PCBs and body size explained much of the separation of turtles by foraging aggregation in a principal component analysis. Turtles from SDB had significantly (p < 0.001) higher total PCBs than SBNWR turtles. Most PCBs detected in turtles were non-dioxin-like PCB congeners (153, 138, 99) that are associated with neurotoxicity. Recaptured turtles' POP levels changed significantly over time indicating significant variation in POP levels through time and space, even among adjacent foraging locations.


Assuntos
Monitoramento Ambiental , Tartarugas/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , California , Ecossistema , Compostos Orgânicos/metabolismo , Bifenilos Policlorados/metabolismo
6.
Environ Monit Assess ; 192(5): 277, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32274592

RESUMO

The potential bioaccumulation of sediment-associated contaminants is one of the primary concerns associated with the aquatic placement of dredged sediment. Laboratory bioaccumulation tests with representative infaunal organisms exposed to dredged sediment and reference sediment are used to assess the potential for contaminant-related bioaccumulation impacts. Dredged sediment testing and evaluation guidance provides statistical inferences and numerous assessment factors (e.g., the magnitude of difference (MOD)) to interpret results; however, detailed information for applying these factors is lacking. Therefore, the focus of this work was to provide context for the application of the MOD as a line of evidence for evaluating bioaccumulation risk associated with dredged material placement in aquatic environments by considering variance (as coefficient of variation (CV)), MOD, and statistical differences associated with bioaccumulation bioassay tissue concentrations in three case studies. Based on peer-reviewed data and dredged material monitoring data, relatively low within-sample variability (CVs < 50%) of tissue concentrations can be achieved for commonly assessed constituents (e.g., polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), metals, and butyl tins). Thus, statistical comparisons were generally able to detect significant differences (p < 0.05; α = 0.05) across tissue concentrations with relatively low MODs (< 2-fold difference). Based on the observed variance, MOD, and statistical differences associated with bioaccumulation bioassay tissue concentrations, a 2-fold MOD can provide an additional line of evidence to evaluate bioaccumulative risk when statistical significance is observed. These results indicated that a judicious consideration of the sample variance and MOD is a useful factor when discerning meaningful differences among contaminant tissue concentrations.


Assuntos
Bioacumulação , Sedimentos Geológicos/química , Poluentes Químicos da Água , Monitoramento Ambiental , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos
7.
Mar Pollut Bull ; 153: 110956, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275520

RESUMO

The objective of this paper is to determine whether contaminant data on mussels and sediments can be used interchangeably, or not, when assessing the degree of anthropogenic contamination of a water body. To obtain adequate coverage of the entire Gulf of Maine, Bay of Fundy sediment samples were collected, analyzed and combined with similar data from four coastal monitoring programs. This required careful interpretation but provided robust results consistent with published literature. A strong correspondence was found between sediment and mussel concentrations for polycyclic aromatic hydrocarbons, moderate to weak correspondence for polychlorinated biphenyls, and except for mercury and zinc, little to no correspondence was found for metals. We conclude that mussel contaminant data are likely sufficient for providing information on the spatial and temporal distribution of chemical contaminants, in coastal waters, under a broad range of environmental conditions and contaminant levels, and unlike sediments, provide direct information on contaminant bioavailability.


Assuntos
Monitoramento Ambiental , Mytilus edulis , Poluentes Químicos da Água , Animais , Sedimentos Geológicos , Maine , Mytilus , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos
8.
PLoS One ; 15(3): e0230629, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32231376

RESUMO

Food safety crises involving persistent organic pollutants [POPs, e.g. dioxins, polychlorinated biphenyls (PCBs), organochlorine pesticides] lead to systematic slaughter of livestock to prevent their entry into the food chain. Therefore, there is a need to develop strategies to depurate livestock moderately contaminated with POPs in order to reduce such economic and social damages. This study aimed to test a POPs depuration strategy based on undernutrition (37% of energy requirements) combined with mineral oil (10% in total dry matter intake) in nine non-lactating ewes contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and PCBs 126 and 153. In order to better understand the underlying mechanisms of the depuration process, POPs kinetics and body lipids dynamics were followed concomitantly over 57-day of depuration in POPs storage (adipose tissue, AT), central distribution (blood) and excretion (faeces) compartments. Faecal POPs concentrations in underfed and mineral oil supplemented ewes increased by 2.0 to 2.6-fold, but not proportionally to lipids concentration which increased by 6-fold, compared to the control ewes. Nonetheless, after 57 days of depuration in undernutrition and mineral oil supplementation, AT POPs concentrations were 1.5 to 1.6-fold higher while serum concentrations remained unchanged compared to the control ewes. This was concomitant with a decrease by 2.7-fold of the AT estimated lipids weight along the depuration period. This reduction of the volume of the storage compartment combined with the increase of POPs faecal excretion in underfed and mineral oil supplemented ewes led to a reduction by 1.5-fold of the PCB 126 AT burden, while no changes were observed for TCDD and PCB 153 burdens (vs. no change for PCB 126 and increases for TCDD and PCB 153 AT burdens in control ewes). The original approach of this study combining the fine description at once of POPs kinetic and of body lipids dynamic improved our understanding of POPs fate in the ruminant.


Assuntos
Tecido Adiposo/metabolismo , Gorduras Insaturadas na Dieta/administração & dosagem , Dioxinas/metabolismo , Fezes/química , Desnutrição/patologia , Bifenilos Policlorados/metabolismo , Tecido Adiposo/química , Animais , Carga Corporal (Radioterapia) , Peso Corporal , Dioxinas/análise , Dioxinas/sangue , Poluentes Ambientais/análise , Poluentes Ambientais/sangue , Poluentes Ambientais/metabolismo , Cinética , Lipídeos/sangue , Bifenilos Policlorados/análise , Bifenilos Policlorados/sangue , Ovinos
9.
PLoS One ; 15(3): e0230628, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32231383

RESUMO

Food safety crises involving persistent organic pollutants (POPs) lead to systematic slaughter of livestock to prevent contaminants from entering the food chain. Therefore, there is a need to develop strategies to depurate livestock moderately contaminated with POPs to reduce economic and social damage. This study aimed to test undernutrition (37% of energy requirements) combined with mineral oil (10% in total dry matter intake) in nine non-lactating ewes contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyls (PCBs) 126 and 153 as a strategy to enhance the depuration of POPs through faecal excretion. To better understand the underlying mechanisms of the depuration process, lipophilic POPs and lipid fluxes were co-monitored in various body and excretion compartments. Body compartments (adipose tissues, muscle, liver and blood) and the total empty body were analyzed for lipids and POPs concentrations and burdens at slaughter, as well as excretion compartments (faeces and wool) collected during the depuration period. Decreases in empty body total and lipid weights were 6-fold higher in underfed and supplemented ewes compared to control ewes. In addition, over the depuration period undernutrition and supplementation treatment increased faecal TCDD, PCBs 126 and 153 excretions by 1.4- to 2.1-fold but tended to decrease wool PCB 153 excretion by 1.4-fold. This induced 2- to 3-fold higher decreases in the empty body POPs burdens for underfed and supplemented ewes. Nonetheless, when expressed relative to the calculated initial empty body burdens, burdens at slaughter decreased only slightly from 97%, 103% and 98% for control ewes to 92%, 97% and 94% for underfed and supplemented ones, for TCDD, PCBs 126 and 153, respectively. Fine descriptions at once of POPs kinetic (companion paper 1) and mass balance (companion paper 2), and of body lipid dynamics were very useful in improving our understanding of the fate of POPs in the ruminants.


Assuntos
Tecido Adiposo/química , Gorduras Insaturadas na Dieta/administração & dosagem , Dioxinas/análise , Fígado/química , Desnutrição/patologia , Bifenilos Policlorados/análise , Tecido Adiposo/metabolismo , Animais , Carga Corporal (Radioterapia) , Peso Corporal , Poluentes Ambientais/análise , Fezes/química , Fígado/metabolismo , Ovinos , Lã/química , Lã/metabolismo
10.
Crit Rev Oncol Hematol ; 150: 102950, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32339980

RESUMO

Incidence and mortality of thyroid cancer are increasing, thus making mandatory to improve the knowledge of disease etiology. The hypothesis of a role for anthropogenic chemicals is raising wide consideration. A series of occupational studies revealed that job exposures with high risk of chemical contamination were usually more prone to thyroid cancer development. These include shoe manufacture, preserving industry, building activities, pulp/papermaker industry and the wood processing, agricultural activities, and other work categories characterized by contact with chemicals, such as chemists and pharmacists. However, such epidemiological analyses cannot define a causal relationship. Thyroid-disrupting activity has emerged for a broad set of anthropogenic chemicals, with the best evidence being gained for polychlorinated biphenyls, polybrominated diphenyl ethers, dioxins, bisphenols, phthalates, pesticides, and heavy metals. A series of case-control studies, assessing exposure to thyroid-disrupting agents, as measured on biological matrices, have been recently performed providing the following insights: a) positive relationship with thyroid cancer was found for phthalates, bisphenols, the heavy metals cadmium, copper, and lead; b) polybrominated diphenyl ethers exposure showed no relationship with thyroid cancer c) controversial results were reported for polychlorinated biphenyls and pesticides. However, such studies cannot demonstrate the causal link with disease occurrence, as exposure is assessed after tumour development. Studies with different methodological approach are therefore required for defining the role of anthropogenic environmental chemicals in thyroid carcinogenesis.


Assuntos
Dioxinas/efeitos adversos , Poluentes Ambientais/efeitos adversos , Praguicidas/efeitos adversos , Bifenil Polibromatos/efeitos adversos , Bifenilos Policlorados/efeitos adversos , Glândula Tireoide/efeitos dos fármacos , Neoplasias da Glândula Tireoide/induzido quimicamente , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados , Humanos , Praguicidas/metabolismo , Fenóis/toxicidade , Éteres Fenílicos/efeitos adversos , Glândula Tireoide/fisiologia
11.
Sci Total Environ ; 722: 137776, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32199362

RESUMO

Organochlorine (OC) profiles have been used as chemical "fingerprints" to infer an animal's foraging area. North Pacific killer whale (Orcinus orca) populations are exposed to different levels and patterns of OCs based on their prey, distribution, and amount of time spent in a particular area. To characterize concentrations and profiles of OCs found in various populations of North Pacific killer whales, polychlorinated biphenyls (PCBs), including dioxin-like congeners, DDTs, and hexachlorobenzene (HCB), were measured in biopsy blubber samples of photo-identified resident (fish-eating) and transient (mammal-eating) killer whales collected from 1994 through 2002 from Russian Far East waters to the waters of the west coast of the United States, representing 10 populations. We compared blubber OC concentrations based on ecotype (resident vs. transient), sex and reproductive maturity, and geographic area. We also examined OC mixtures to determine if we could detect segregated geographical areas (foraging areas) among the six populations with sufficient sample sizes. Transients had significantly higher OC concentrations than residents and adult male whales had consistently higher OC levels compared to adult females, regardless of ecotype. Our OC profile findings indicate segregated foraging areas for the North Pacific killer whales, consistent with observations of their geographic distributions. Several potential health risks have also been associated with exposure to high levels of contaminants in top-level predators including reproductive impairment, immune suppression, skeletal deformities, and carcinoma. The results of this baseline study provide information on the geographic distribution of OCs found in North Pacific killer whales, results which are crucial for assessing the potential health risks associated with OC exposure in this species.


Assuntos
Orca , Animais , Monitoramento Ambiental , Extremo Oriente , Feminino , Masculino , Bifenilos Policlorados , Federação Russa , Poluentes Químicos da Água
12.
PLoS One ; 15(3): e0230283, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32191759

RESUMO

Polychlorinated biphenyls (PCBs) are worldwide chemical pollutants that have been linked to disrupted reproduction and altered sexual behaviour in many organisms. However, the effect of developmental PCB-exposure on adult passerine reproductive behaviour remains unknown. A commercial PCB mixture (Aroclor 1242) or an estrogenic congener (PCB 52) were administered in sublethal amounts to nestling zebra finches (Taeniopygia guttata) in the laboratory to identify effects of developmental PCB-exposure on adult zebra finch reproductive parameters. Results indicate that although traditional measures of reproductive success are not altered by this PCB dosage, PCBs do alter sexual behaviours such as male song and nesting behaviour. Males treated with PCB 52 in the nest sang significantly fewer syllables than control males, while females treated with Aroclor 1242 in the nest showed the strongest song preferences. PCB treatment also caused an increase in the number of nesting attempts and abandoned nests in the Aroclor 1242 treatment relative to the PCB 52 treatment, and offspring with control fathers fledged significantly earlier than those with fathers treated with Aroclor 1242. Behavioural differences between males seem to best explain these reproductive effects, most notably aggression. These findings suggest that sublethal PCB-exposure during development can significantly alter key reproductive characteristics of adult zebra finches, likely reducing fitness in the wild.


Assuntos
Comportamento Animal/efeitos dos fármacos , Exposição Ambiental , Tentilhões/crescimento & desenvolvimento , Bifenilos Policlorados/toxicidade , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/fisiologia , Feminino , Masculino , Comportamento de Nidação/efeitos dos fármacos , Vocalização Animal
13.
Sci Total Environ ; 720: 137597, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32143051

RESUMO

Polychlorinated biphenyls (PCBs) exposure is closely associated with the prevalence of metabolic diseases, including fatty liver and dyslipidemia. Emerging literature suggests that disturbance of gut microbiota is related to PCB126-induced metabolic disorders. However, the causal role of dysbiosis in PCB126-induced fatty liver is still unknown. To clarify the role of the gut microbiome in the detoxification of PCB126 in intestine or PCB126-induced toxicity in liver, mice were administrated with drinking water containing antibiotics (ampicillin, vancomycin, neomycin, and metronidazole) or Inulin. We showed that PCB126 resulted in significant hepatic lipid accumulation, inflammation, and fibrosis. PCB126, Antibiotics, and Inulin significantly affected the structure and shifted community membership of gut microbiome. 7 KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways at level 2 and 39 KEGG pathways at level 3 were significantly affected. Antibiotics alleviated PCB126-induced fibrosis in the liver but increased inflammation. Inulin treatment ameliorated both inflammation and fibrosis in the liver of PCB126-treated mice. Neither Antibiotics nor Inulin had significant effect on PCB126-induced hepatic steatosis. The more specific intervention of gut microbiota is needed to alleviate PCB126-induced fatty liver. These data demonstrate that homeostasis of gut microbiota is critical for the defense against PCB126 toxicity and dysbiosis plays a fundamental role in the development of inflammation and fibrosis in liver of PCB126-treated mice.


Assuntos
Microbioma Gastrointestinal , Animais , Disbiose , Homeostase , Fígado , Camundongos , Bifenilos Policlorados
14.
Ecotoxicol Environ Saf ; 195: 110376, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32200152

RESUMO

While contamination of indoor environment with organochlorine compounds (OCs) is well documented worldwide, only a few studies highlighted the problem of indoor pollution in Indian sub-continent, including Nepal. This study insight the contamination level, distribution pattern, and sources of OCs in indoor dust from a rural area of Nepal. Additionally, daily exposure risk through different intake pathways was estimated in order to mark the potential risk of OCs to local residents. Results indicated the predominance of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in dust. Æ©26OCPs (median 87 ng/g) in dust was about 7-8 times greater than Æ©30PCBs (median 10.5 ng/g). DDT was the most abundant chemical among Æ©26OCPs, followed by HCHs and endosulfan, and accounted for 73%, 7%, and 4% of Æ©26OCPs, respectively. A relatively high level of Æ©DDT than other OCPs suggests the existence of DDT source in the Nepalese environment. Among PCB, tetra-CBs were most prevalent, trailed by penta-CBs, hexa-CBs, and hepta-CBs, and comprised 28%, 21%, 17% and 17% of Æ©30PCBs, respectively. Dioxin like-PCBs (median 3.48 ng/g) was about two times higher than the total indicator-PCB (median 1.63 ng/g). High p,p-DDT/p,p-DDE ratio (median 2.89) suggested fresh application and minimal degradation of DDT in the local environment of Kopawa. While lower α-/γ-HCH ratio (median 0.75) indicated lindane contamination as the primary sources of HCH. Moreover, the low α-/ß-endosulfan ratio (median 0.86) specified the fresh use of commercial endosulfan. Among OCPs, only DDT positively related to total organic carbon (TOC) (Rho = 0.55, p < 0.05) but not black carbon (BC), proposing minimal or zero impact of TOC and BC. For PCBs, PCB-126 was moderately and negatively correlated with TOC (Rho = -0.49, p < 0.05), but not BC. The daily risk exposure (DRE) assessment showed that children are more vulnerable to OCs than the adult. The DRE of OCs in this study were 2-4 order of magnitude lower than their corresponding reference dose (RfD), proposing insignificant risk.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Poeira/análise , Monitoramento Ambiental/métodos , Hexaclorocicloexano/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Adulto , Criança , Endossulfano/análise , Humanos , Nepal , População Rural , Fuligem/análise
15.
Mar Pollut Bull ; 154: 111043, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32174493

RESUMO

A total of 23 sediment samples are collected from Ross Sea and Drake Passage to investigate the distribution characteristics of polychlorinated biphenyls (PCBs) in the Antarctic marine sediments. Over 51 kinds of PCBs are detected through exhaustive searches using multiple reaction monitoring system. The results show that the concentration of individual PCB congener and total PCBs vary greatly among sampling sites, ranging from not detected to 49.75 ng g-1 and 3.77 to 246.86 ng g-1, respectively. The average PCBs level in Ross Sea is ten times higher than that in Drake Passage. Two different homologues, hexa- and tetra-CBs, give high contributions to ∑PCBs level in most samples from Ross Sea and Drake Passage, respectively. Our results support that the marine sediments might be an important sink for PCBs. Besides, the biological pump and the primary productivity might be responsible for the distribution differences of PCBs between Ross Sea and Drake Passage.


Assuntos
Monitoramento Ambiental , Bifenilos Policlorados , Poluentes Químicos da Água , Regiões Antárticas , Sedimentos Geológicos
16.
Ecotoxicol Environ Saf ; 194: 110338, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32135376

RESUMO

2,2',3,5',6-Pentachlorobiphenyl (PCB95) is known as a persistent pollutant that was found in eggs in China. PCB 95 can be metabolized into OH-PCB95 and MeO-PCB95 in liver microsomes. However, the toxicity and its mechanism of PCB95 or its metabolites have been little studied on laying hens. Herein, chicken embryo liver cells of laying hens were selected and treated with different levels of PCB95 and its two metabolites, and the EC50 of PCB95, OH-PCB95, MeO-PCB95 was 80.85, 4.81 and 107.04 µg/mL respectively, indicating that OH-PCB95 is much more cytotoxic than PCB95 or MeO-PCB95. Targeted metabolomics was further used to study the effects of the parent compound and its metabolites on cell metabolism. The results showed that four primary types of glycerophospholipids were down-regulated after exposure to PCB95 and its metabolites, especially PE and PS (60% more than the control for PCB95, 40% for OH-PCB95, and less than 40% for MeO-PCB95). KEGG pathway analysis based on amino acid metabolism showed that PCB95 may mainly interfere with the amino acids involved in immune regulation (phenylalanine and tyrosine), and OH-PCB95 may be associated with genetic disoders (cysteine, methionine and purine metabolism). However, the metabolic pathways induced by MeO-PCB95 are quite different from those induced by PCB95 and OH-PCB95, affecting mainly D-glutamine and D-glutamate metabolism, alanine and glutamate metabolism, and arginine and proline metabolism; these pathways mainly regulate the elimination of excess purines and are involved in the synthesis of the amino acids required by cells. These results showed that OH-PCB95 has the highest toxicity on chicken embryo liver cells and MeO-PCB95 could be a detoxification product of PCB95 and OH-PCB95. This study contributes to the understanding of the different effects of PCB95 and its metabolites on cellular metabolism, and the data are helpful in evaluating the hepatotoxic effects of these compounds.


Assuntos
Poluentes Ambientais/toxicidade , Bifenilos Policlorados/toxicidade , Aminoácidos/metabolismo , Animais , Embrião de Galinha , Galinhas/metabolismo , China , Ovos , Poluentes Ambientais/metabolismo , Feminino , Hepatócitos/metabolismo , Fígado/metabolismo , Redes e Vias Metabólicas , Metabolômica , Metionina/metabolismo , Microssomos Hepáticos/metabolismo , Testes de Toxicidade
17.
Ecotoxicol Environ Saf ; 194: 110339, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32143103

RESUMO

Serum and breast milk are both important biological samples to evaluate body burden of dioxin-like compounds which include polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs). We collected maternal serum at early pregnancy, and breast milk at 3-8 weeks after delivery from 55 mothers living in Beijing, China, and measured 29 dioxin-like compounds in these samples. The sampling intervals in this study were extended up to 10 months to analyze differences of contents between serum and breast milk under long sampling intervals. The results showed that mean TEq level of PCDD/Fs in serum (9.8 pg TEq g-1 lipid) was 1.7 times higher than that in milk (4.5 pg TEq g-1 lipid), while the TEq concentrations of dl-PCBs in serum (1.2 pg TEq g-1 lipid) was significantly lower than that in milk (2.0 pg TEq g-1 lipid). There were only two congeners, OCDD (r = 0.32) and PCB105 (r = 0.33), the correlations of which between serum and milk were significant. The differences in distributions of congeners in serum and milk might be influenced by number of chlorine substituents and structures of congeners. In addition, maternal age and BMI were positively and negatively correlated with mass concentrations of dioxin-like compounds in milk and serum respectively. These results suggest that, compared with serum, it is limited to use breast milk to assess long-term exposure for the wider population.


Assuntos
Dioxinas/metabolismo , Poluentes Ambientais/metabolismo , Leite Humano/metabolismo , Pequim , Benzofuranos/análise , Carga Corporal (Radioterapia) , China , Cloretos/análise , Cloro/análise , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Dioxinas/análise , Dioxinas/sangue , Poluentes Ambientais/análise , Poluentes Ambientais/sangue , Feminino , Humanos , Lipídeos/análise , Exposição Materna/estatística & dados numéricos , Leite Humano/química , Bifenilos Policlorados , Dibenzodioxinas Policloradas/análise , Gravidez
18.
Environ Pollut ; 260: 114004, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32004963

RESUMO

The metabolic syndrome (MetS) is a group of diseases that tend to occur together, including diabetes, hypertension, central obesity, cardiovascular disease and hyperlipidemia. Exposure to persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) has been associated with increased risk of development of several of the components of the MetS. The goal of this study is to determine whether the associations with POPs are identical for each of the components and for the MetS. The subject population was 601 Native Americans (Akwesasne Mohawks) ages 18 to 84 who answered a questionnaire, were measured for height and weight and provided blood samples for clinical chemistries (serum lipids and fasting glucose) and analysis of 101 PCB congeners and three OCPs [dichlorodiphenyldichloroethylene (DDE), hexachlorobenzene (HCB) and mirex]. Associations between concentrations of total PCBs and pesticides, as well as various PCB congener groups with each of the different components of the MetS were determine so as to ask whether there were similar risk factors for all components of the MetS. After adjustment for other contaminants, diabetes and hypertension were strongly associated with lower chlorinated and mono-ortho PCBs, but not other PCB groups or pesticides. Obesity was most closely associated with highly chlorinated PCBs and was negatively associated with mirex. High serum lipids were most strongly associated with higher chlorinated PCBs and PCBs with multiple ortho-substituted chlorines, as well as total pesticides, DDE and HCB. Cardiovascular disease was not closely associated with levels of any of the measured POPs. While exposure to POPs is associated with increased risk of most of the various diseases comprising the MetS, the specific contaminants associated with risk of the component diseases are not the same.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Síndrome Metabólica/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Hidrocarbonetos Clorados , Índios Norte-Americanos/estatística & dados numéricos , Pessoa de Meia-Idade , Praguicidas , Bifenilos Policlorados , Estados Unidos/etnologia , Adulto Jovem
19.
Sci Total Environ ; 714: 136660, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32018953

RESUMO

This study aimed to assess the longitudinal association between PCB exposure and the subsequent occurrence of hypertension in a highly polluted area. The study subjects had at least one PCB serum measurement between 2003 and 2014 and were followed up to the end of 2017. Hypertension cases were obtained from the Brescia Health Protection Agency database. Risk ratios of hypertension for total PCBs, high-, middle- and low-chlorinated groups and some common congeners were estimated using Poisson regression models. 1031 subjects were included (43.4% males, mean age 45.3 years). 229 subjects developed hypertension during the follow-up. Total PCBs, middle- and high-chlorinated PCBs, and particularly PCB congeners 138, 153 and 180 were associated with an about 2-fold increased risk of hypertension comparing the third with first tertile of distribution. After lipid-standardization of PCB serum values, the excess risk showed only a slight attenuation. A dose-response linear relationship of the risk of hypertension by PCB serum concentrations as continuous variables was also observed. The PCBs-hypertension association was stronger in overweight/obese subjects than those with normal body mass index. In this prospective cohort study the serum levels of total and middle to high chlorinated (≥6 Cl) PCBs were associated with an increased risk of hypertension, particularly among overweight/obese subjects.


Assuntos
Hipertensão , Estudos de Coortes , Poluentes Ambientais , Feminino , Humanos , Hipertensão/induzido quimicamente , Itália , Masculino , Pessoa de Meia-Idade , Bifenilos Policlorados , Estudos Prospectivos
20.
Chemosphere ; 246: 125849, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32092814

RESUMO

The sodium pyrophosphate (SP)-enhanced Fenton reaction has been proven to have promising potential in remediation of polychlorinated biphenyls in soils by keeping iron ions soluble at high pH and minimizing the useless decomposition of H2O2. However, little information can be obtained about the effect of environmental factors on its remediation performance. Thus, the effect of environmental factors on the degradation of 2,2',5-trichlorodiphenyl (PCB18), one of the main PCB congeners in Chinese sites, was investigated in this study. PCB18 degradation was sensitive to pH, which ranged from 39.8% to 99.5% as increased pH from 3.0 to 9.0. ·OH was responsible for PCB18 degradation at pH 5.0, while both ·OH and O2- resulted in PCB 18 degradation at pH 7.0 with the calculated reaction activation energy of 73.5 kJ mol-1. Bivalent cations and transition metal ions decreased PCB18 degradation markedly as their concentrations increased. The addition of humic acid had an inhibitory on PCB18 degradation, but no obvious inhibition of PCB18 removal was observed when the same concentration of fulvic acid was added. The addition of 1 and 10 µM model humic constituents (MHCs) promoted PCB18 degradation, but the addition of 100 µM MHCs decreased PCB18 removal. Biphenyl, two dichlorobiphenyl, and two hydroxy trichlorobiphenyl derivatives were identified as the major degradation products of PCB18 in the Fe2+/SP/H2O2 system at pH 7.0. Thus, an oxidative pathway contributed by OH and a reductive pathway induced by O2- were proposed as the main mechanisms for PCB18 degradation in the SP-enhanced Fenton reaction.


Assuntos
Compostos de Bifenilo/química , Poluentes Ambientais/química , Modelos Químicos , Quelantes , Substâncias Húmicas , Peróxido de Hidrogênio/química , Ferro/química , Oxirredução , Bifenilos Policlorados/química , Solo
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