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1.
Huan Jing Ke Xue ; 43(1): 500-509, 2022 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-34989535

RESUMO

The residual content of organochlorine pesticides (OCPs) in soil and crops of typical agricultural land in the southern Leizhou peninsula were determined using gas chromatography-mass spectrometry (GC-MS). Additionally, the bioconcentration factors of organochlorine pesticides in eight crops were investigated, and the human health risk was evaluated. The results indicated that 10 types of OCPs were detected to varying degrees; HCHs and heptachlor were the main OCPs in the study area, with the residual contents of 23.83-111.51 ng·g-1 and 11.01-25.97 ng·g-1 in soil and 7.54-61.28 ng·g-1 and 3.96-30.97 ng·g-1 in crops, respectively. A small number of soil and crop samples were found to exceed the standard. The ratio of α-HCH/γ-HCH was less than 1 in 87.50% of the soil samples, and ß-HCH/α-HCH was larger than 1. This indicates that the HCHs were probably derived from the recent use of lindane and historical residual pollution, whereas the heptachlor was mainly derived from underground insect pests and the application of termite control agents. The enrichment ability of OCPs was significantly different among different crops. The bioaccumulation capacity of vegetables was higher than that of fruit. Furthermore, bulb vegetables (leeks) were significantly stronger than other vegetables. A human health risk assessment of OCPs showed that OCP-combined pollution would not cause significant health risks to the population in the study area. However, the maximum value of HI in some crop samples was greater than 1, indicating that there were still potential risks, which should not be ignored.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Poluentes do Solo , China , Monitoramento Ambiental , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Medição de Risco , Solo , Poluentes do Solo/análise
2.
Environ Pollut ; 292(Pt A): 118362, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34648836

RESUMO

The fetus is prenatally exposed to a mixture of organochlorine pesticides (OCPs), mercury (Hg), docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and selenium (Se) through maternal seafood consumption in real-life scenario. Prenatal exposure to these contaminants and nutrients has been suggested to affect thyroid hormone (TH) status in newborns, but the potential relationships between them are unclear and the joint effects of the mixture are seldom analyzed. The aim of the study is to investigate the associations of prenatal exposure to a mixture of OCPs, Hg, DHA, EPA and Se with TH parameters in newborns. 228 mother-infant pairs in Shanghai, China were included. We measured 20 OCPs, total Hg, DHA, EPA and Se in cord blood samples as exposure variables. The total thyroxine (TT4), free thyroxine (FT4), total triiodothyronine (TT3), free triiodothyronine (FT3), and thyroid-stimulating hormone (TSH) levels and the FT3/FT4 ratio in cord serum were determined as outcomes. Using linear regression models, generalized additive models and Bayesian kernel machine regression, we found dose-response relationships of the mixture component with outcomes: among the contaminants, p,p'-DDE was the most important positive predictor of TT3, while HCB was predominantly positively associated with FT3 and the FT3/FT4 ratio, indicating different mechanisms underlying these relationships; among the nutrients, EPA was first found to be positively related to the FT3/FT4 ratio. Additionally, we found suggestive evidence of interactions between p,p'-DDE and HCB on both TT3 and FT3, and EPA by HCB interactions for TT3, FT3 and FT3/FT4 ratio. However, the overall effects of the mixture on thyroid hormone parameters were not significant. Our result suggests that prenatal exposure to p,p'-DDE, HCB and EPA as part of a mixture might affect thyroid function of newborns in independent and interactive ways. The potential biological mechanisms merit further investigation.


Assuntos
Hidrocarbonetos Clorados , Mercúrio , Praguicidas , Teorema de Bayes , China , Feminino , Sangue Fetal , Humanos , Hidrocarbonetos Clorados/toxicidade , Recém-Nascido , Nutrientes , Gravidez , Hormônios Tireóideos , Tireotropina , Tiroxina
3.
Sci Total Environ ; 806(Pt 4): 150922, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655625

RESUMO

Humans are exposed every day to assorted environmental pollutants namely, polychlorinated biphenyls (PCB), organochlorine pesticides (OCP), brominated flame-retardants (BFR), polycyclic aromatic hydrocarbons (PAH), synthetic musks, heavy metals (e.g. cadmium) and plastic additives (e.g. bisphenol A, BPA). Besides environmental persistence, biomagnification and bioaccumulative properties, these pollutants are classified as endocrine disruptors (EDs), metabolic disruptors, neurologic disruptors. These compounds affect the normal function of several mechanisms in the human body being linked to human health issues as cancer development (e.g. breast, uterine and endometrial), miscarriage, birth defects, premature delivery and infertility. In order to prevent future health issue of women and possible progeny, the assessment of EDs accumulated is essential, particularly in adipose tissue. These samples have been referred as the ideal matrix to establish over time accumulation and long-term exposure of persistent and non-persistent lipophilic EDs. However, the invasive sample collection procedure and methodology processing discourages the usage of this matrix for biomonitoring studies. In this review, a Web of Science search without any publishing year restriction on the analysis in adipose tissue of PCB, OCP, BPA, cadmium, BFR and synthetic musks was performed. A total of 313 studies were found, 158 were European studies from which the studies with data on women EDs accumulation were selected for detailed analysis (n = 90). The results were structured and presented in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The present paper is an overview on the existent EDs analytical methods and levels accumulated in women adipose tissue, with the correspondent health implications across Europe. The limits of detection and quantification were compared and a discussion with results obtained about the presence of ED was performed.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Tecido Adiposo/química , Monitoramento Biológico , Monitoramento Ambiental , Poluentes Ambientais/análise , Feminino , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise
4.
Sci Total Environ ; 806(Pt 4): 150824, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655629

RESUMO

Temporal and spatial distribution of organochlorine pesticides (OCPs) and the organophosphate pesticide chlorpyrifos, one of the main insecticides used in Argentina, was evaluated in two populations of the sea anemone Bunodosoma zamponii living under different anthropological stressors: Las Delicias (LD) adjacent to a wastewater plant, and Punta Cantera (PC) a reference site. Pesticides were analyzed throughout the year in water, sediments and whole organisms. Chlorpyrifos represented 50% of the total pesticide found in water samples during winter. HCHs and drins were predominant in sediment samples, mainly in LD. Total pesticide concentration in anemones from LD was higher than those from PC during winter (mainly associated with HCHs, endosulfans, DDTs and chlorpyrifos levels), coincident with the main period of effluent discharge to the coast after pesticide applications and also the rainiest season. Dissimilarities among anemones populations could stem from a differential input of pesticides in each site and/or a contrasting physiological status of the populations.


Assuntos
Clorpirifos , Hidrocarbonetos Clorados , Praguicidas , Anêmonas-do-Mar , Poluentes Químicos da Água , Animais , Argentina , China , Monitoramento Ambiental , Sedimentos Geológicos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise
5.
Sci Total Environ ; 806(Pt 4): 150969, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34656600

RESUMO

Because of their highly persistent, bioaccumulative and toxic properties, short-chain chlorinated paraffins (SCCPs) have become emerging contaminants and have been included in Annex A (elimination) of the Stockholm Convention since 2017. The contamination of SCCPs has been observed in the environment and biota worldwide but has not been detected in Taiwanese river ecosystems. Thus, this study aimed to determine the occurrence of SCCPs in sediments and fish from 30 major rivers in Taiwan and to evaluate the risk of SCCPs to river ecosystems and human health. The concentrations of SCCPs in sediments and fish ranged from ND (not detected) to 12.6 mg/kg dw and ND to 2.07 mg/kg ww, respectively. The concentrations of SCCPs in sediments were significantly correlated with some indicators of the discharge sources and water quality variables, indicating that SCCPs were released via human activities and various discharges into rivers and accumulated in sediments. The bioaccumulation of SCCPs in fish exhibited species-specific profiles and was related to environmental contamination levels and the living pattern and trophic level of the fish. The SCCP levels in sediments from 20 major rivers in Taiwan might pose a potential ecological risk to river ecosystems according to the criteria of the Federal Environmental Quality Guidelines in Canada, the biota-sediment accumulation factor and the risk quotient. Consumption of SCCP-contaminated river fish by different gender and age groups showed no significant health risk to residents in Taiwan evaluated by the estimated daily intake and hazard quotient. However, there was a health concern for the 0- to 3-year-old group due to the consumption of contaminated river fish at a bioaccessibility of 100% for SCCPs by the margin of exposure. Routine monitoring of SCCPs in river ecosystems is needed to protect aquatic organisms and human health.


Assuntos
Hidrocarbonetos Clorados , Parafina , Animais , Pré-Escolar , China , Ecossistema , Monitoramento Ambiental , Humanos , Hidrocarbonetos Clorados/análise , Lactente , Recém-Nascido , Parafina/análise , Medição de Risco , Taiwan
6.
Sci Total Environ ; 806(Pt 4): 151369, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34740652

RESUMO

Despite the intensive use of organochlorine pesticides (OCPs) in the proximity of the Gulf of California, there is no information regarding their levels in predatory shark species, which could be exposed to relatively high concentrations. In this area, neonates and juveniles of the critically endangered scalloped hammerhead Sphyrna lewini are caught for consumption, so the examination of the accumulation of OCPs is necessary for future conservation, as well as to assess the exposure to humans. Levels and accumulation patterns of 29 OCPs were analyzed in the liver and muscle of 20 immature scalloped hammerheads. Twenty-three compounds were detected in liver and 17 OCPs were found in muscle. In the latter tissue, only p,p'-DDE presented concentrations above the detection limit in all samples (0.59 ± 0.21 ng/g w.w.), while in the liver, DDTs were also the main group of pesticides (215 ± 317 ng/g w.w.), followed by ∑Chlordanes > ∑Chlorobenzenes > Mirex > HCBD > Others. One of the two analyzed neonates presented high concentrations of OCPs in the liver (1830 ng/g w.w.), attributed to a bioamplification process. No differences in accumulation of OCPs were found between juveniles of both sexes, where an increase in the concentration of various compounds related with size and age was observed. Additionally, juveniles under 2 years of age may undergo a growth dilution process. Our results suggest that the consumption of this species does not imply risks to human health (chronic or carcinogenic effects) associated with OCPs. Likewise, we recommend further monitoring due to the possible recent inputs of some OCPs (e.g. dicofol, median of ratio o, p'-DDT/p, p'-DDT = 0.7) into the environment.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Tubarões , Animais , Bioacumulação , DDT/análise , Monitoramento Ambiental , Humanos , Hidrocarbonetos Clorados/análise , México , Praguicidas/análise
7.
J Environ Sci (China) ; 112: 16-24, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34955199

RESUMO

Dechloranes are a group of halogenated flame retardants with a basic bicyclo[2.2.1]heptene, including Dechlorane Plus (DP), Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603) and Dechlorane 604 (Dec 604). A few epidemiological investigations and animal experiments have shown that DP exhibited thyroid-interfering effects. In the present study, we investigated whether DP and three other dechloranes could interfere the thyroid function through thyroid hormone receptors (TRs, TRα and TRß) signaling pathways. The binding affinities of the four dechloranes to the two TRs were determined by fluorescence competitive binding assay. It was found that all the four dechloranes could bind with the two TRs. The relative potency (RP) values ranged from nd (not detectable) to 0.0667. Between the two TRs, dechloranes were more inclined to bind with TRß, which implies that the thyroid interference effect of dechloranes may have selectivity in different tissues and organs. TRs-mediated luciferase reporter gene assay and T-screen assay showed that all the four dechloranes exhibited antagonistic activity to TRs in the cells. Taken together, our results demonstrated that dechloranes might interfere with thyroid function by binding with TRs and acting as TR antagonists. The health risk of highly exposed human populations should be of serious concern because of the high hazard quotient calculated from our cell assay results.


Assuntos
Retardadores de Chama , Hidrocarbonetos Clorados , Animais , Monitoramento Ambiental , Retardadores de Chama/análise , Retardadores de Chama/toxicidade , Humanos , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Receptores dos Hormônios Tireóideos/genética
8.
Environ Pollut ; 295: 118666, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34896399

RESUMO

Since the fifties, organochlorine pesticides (OCPs) had been used in agriculture to protect vegetables. Two decades after their ban by the Stockholm convention in 2001, OCPs are still present in agricultural soils inducing vegetable contamination with concentrations above Maximum Residue Level (MRL). This is a major concern for a 5 km2 peri-urban vegetable growing valley located in the south west of France. In the present work, the sampling method was developed to clarify the spatial distribution of one OCP, Dieldrin, and its relationship with soil properties at the scale of study area. A total of 99 soil samples was collected for physicochemical analyses and Dieldrin concentrations. Results show Dieldrin concentrations in soils up to 204 µg kg-1. The horizontal distribution of this pesticide is heterogeneous at the study area scale but homogeneous in each reference plot studied. About 85% of the contamination was located in the top soil layers (0-40 cm depth), but Dieldrin may still be quantified at a depth of 80 cm. Among all soil physicochemical parameters analysed, SOM was the most significantly related (P < 10-4) with Dieldrin concentrations, once different grain size fractions were considered. Moreover, results indicate a 33 times higher Dieldrin concentration and/or extractability for coarse sand than for other grain size fractions. These results show that the developed sampling method is adapted for the study area scale as it helps understanding the factors influencing the spatial distribution of Dieldrin. Historical amendments are the predominant factor for the horizontal contamination and deep ploughing for the vertical contamination. Also, the variations of coarse sand repartition in soils prevents identification of relationships between SOM and Dieldrin contamination in bulk soil. Further investigation is required to explain these relationships but these results highlight why no clear relationship between OCPs and SOM was previously identified.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Poluentes do Solo , Agricultura , Dieldrin/análise , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Solo , Poluentes do Solo/análise , Verduras
9.
Chemosphere ; 287(Pt 3): 132300, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34563784

RESUMO

Though many persistent organic pollutants (POPs) are closely regulated the human population is still exposed to these ubiquitous chemicals from the environment and diet. Safe management and human biomonitoring of POPs is necessary to understand the risk of exposure. Within human biomonitoring the mass of sample is often limited, therefore robust methods using smaller sample amounts are necessary. This study developed a 96-well plate solid phase extraction (SPE) method for determination of selected POPs: polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD) and non-persistent novel flame retardants (NFRs) in low volume blood serum. Non-destructive clean-up coupling Oasis HLB extraction plate with Phree phospholipid removal plate was employed. Extraction efficiency was determined at low and high concentrations in certified reference materials NIST SRM 1957 and 1958, respectively. Target compounds deviated from certified values on average by 15% and 21% for SRM 1957 and SRM 1958, respectively. Observed limit of detections (LODs) ranged from 0.36 pg/mL (PCB 180) to 66.07 pg/mL (δ-HCH). The applicability for real samples is demonstrated on 48 samples from pregnant women enrolled in the pilot phase of the CELSPAC: TNG study. In total, 30 target compounds were detected in at least one sample. The method developed here provides a fast and reliable analysis of human blood serum with possibility to introduce automation for the sample preparation procedure.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Éteres Difenil Halogenados/análise , Humanos , Hidrocarbonetos Clorados/análise , Poluentes Orgânicos Persistentes , Praguicidas/análise , Bifenilos Policlorados/análise , Gravidez , Soro/química , Extração em Fase Sólida
10.
Chemosphere ; 286(Pt 2): 131711, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34340115

RESUMO

The levels, fate, and potential sources of 22 organochlorine pesticides (OCPs) in coral tissues and the surrounding air-seawater system from the South China Sea (SCS) were elucidated for the first time. ∑22OCPs (total concentration of 22 OCPs) (16.1-223 pg L-1) was relatively higher in coastal seawater than in offshore seawater, which may be the widespread influence of coastal pollution inputs under the western boundary current. The atmospheric ∑22OCPs were predominantly distributed in the gas phase (48.0-2264 pg m-3) and were mainly influenced by continental air mass origins. The air-seawater exchange of selected OCPs showed that OCPs tended to migrate from the atmosphere to seawater. The distribution of ∑22OCPs in coral tissues (0.02-52.2 ng g-1 dw) was significantly correlated with that in air samples, suggesting that OCPs may have a migration pattern of atmosphere-ocean corals in the SCS. Corals exhibited higher bioaccumulation ability (Log BAFs: 2.42-7.41) for OCPs. Source analysis showed that the new application of technical Chlordanes (CHLs) was primarily responsible for the current levels of CHLs in the surrounding environment over the SCS, while historical residues were the primary sources of other OCPs.


Assuntos
Antozoários , Hidrocarbonetos Clorados , Praguicidas , Animais , China , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Água do Mar
11.
J Hazard Mater ; 423(Pt B): 127125, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34530279

RESUMO

Secondary copper smelting is an important industrial source of unintentionally produced persistent organic pollutants (UPOPs) emissions. Herein, field study on industrial-scale plants was conducted to clarify the levels and profiles of polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and chlorinated polycyclic aromatic hydrocarbons (> 3 rings, Cl-PAHs) from secondary copper smelting plants. The three UPOPs emission levels from the oxygen-enriched smelting furnace were higher than that from the anode furnace, which was attributed to the low-grade raw materials used. The toxic equivalent quantity concentrations of Cl-PAHs were 1.3-4.4 and 4.6-18.9 times higher than that of PCBs and PCNs, respectively. Thus, the emission control of Cl-PAHs in the secondary copper industry should be of concern. The chlorination degree of PCBs and PCNs was ~4 after the gas-cooling stage but was reduced to 1-2 in the stack outlet. This result indicated that the PCBs and PCNs congeners that were generated during the cooling stage were mainly higher-chlorinated. After purification by air pollution control devices (APCDs), the high-chlorinated congeners were removed simultaneously with the fly ash, whereas the low-chlorinated congeners may be regenerated and transferred into the stack gas due to possible memory effect within the APCDs.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Clorados , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Cobre , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Naftalenos , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
12.
Environ Pollut ; 294: 118663, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896218

RESUMO

Chlorinated and brominated polycyclic aromatic hydrocarbons (Cl/Br-PAHs) are persistent organic pollutants with potential carcinogenic toxicities that are even higher than those of their parent PAH congeners. Current knowledge of Cl/Br-PAH sources and emission characteristics is lacking. Electric arc furnace (EAF) steelmaking is a potential source for Cl/Br-PAHs, considering that preheating of raw materials before they enter the EAF could produce suitable conditions for Cl/Br-PAHs formation. In this field study, we identified EAFs as an important source of Cl/Br-PAHs and clarified their emission concentrations, fingerprints by gas chromatography coupled with high-resolution magnetic mass spectrometry. Potential formation mechanisms of Cl/Br-PAHs were also proposed. The mass concentration ranges for Σ18Cl-PAHs and Σ18Br-PAHs in stack gas were 25.85-4191 ng Nm-3 and 1.02-341 ng Nm-3, respectively. The variation of concentration indicated that the steel scrap composition greatly affected the production of Cl/Br-PAHs. The congener ratios including 6-chlorobenzo [a]pyrene/3-chlorofluoranthene and 1-chloroanthracene/1-chloropyrene could be used to estimate the influence of industrial sources on Cl-PAH occurrences in the air. Ring structure growth was the dominant formation pathway for Cl/Br-PAHs, distinctly different from dioxin formation mechanisms dominated by precursor dimerization and chlorination.


Assuntos
Dioxinas , Hidrocarbonetos Clorados , Dibenzodioxinas Policloradas , Hidrocarbonetos Policíclicos Aromáticos , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
13.
J Environ Sci (China) ; 115: 453-464, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34969473

RESUMO

Long-range atmospheric transport (LRAT) plays a crucial role in the occurrence of persistent organic pollutants (POPs) in remote regions. When studying the LRAT of POPs on the Tibetan Plateau, westerly-controlled regions have received insufficient attention compared with regions influenced by the Indian monsoon or air flow from East Asia. We investigated the residual levels of POPs in soils from the eastern Pamirs and used air backward trajectory analysis to elucidate the influence of potential source regions via LRAT. Organochlorine pesticides (OCPs, mainly comprising DDTs, HCHs, and HCB), polychlorinated biphenyls (PCBs, mainly comprising penta- and hexa-CBs), and polycyclic aromatic hydrocarbons (PAHs, mainly comprising three- and four-ring) were detected at low concentrations of 40-1000,

Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo
14.
Chemosphere ; 287(Pt 4): 132372, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34592207

RESUMO

Chlorinated paraffins (CPs) are complex mixtures, which consist of thousands of individual compounds with no dominant representative. Consequently, knowledge on structure and environmental relevance of individual CP congeners is poor. Similarly to the synthesis of individual CPs, the generation of less complex CP mixtures that can be thoroughly analyzed may be used to overcome some drawbacks of the highly complex technical CP mixtures. Here, we present a new synthesis approach to generate such simple CP mixtures by decarboxylation of polyunsaturated fatty acids followed by saturation of the double bonds by chlorination. Specifically, α-linolenic acid (18:3Δ9,12,15) was decarboxylated to heptadecatriene. The resulting raw product was chlorinated with SO2Cl2. Purification by column chromatography led to a main fraction consisting of four major peaks originating from hexachloroheptadecane (C17H30Cl6) isomers (∼80% of the total peak area) along with ∼20 low abundant by-products, according to gas chromatography with electron capture negative ion mass spectrometry. In the same way, decarboxylation and subsequent chlorination of other polyunsaturated fatty acids may lead to further simple CP mixtures with other chain lengths. Although these simple CP mixtures cannot fully reflect the various structural features present in technical mixtures they could be beneficial for transformation studies because changes in the CP pattern can easily be noted which is in contrast to technical CP mixtures. Such simple CP mixtures could also be used in toxicity tests which are difficult to perform with technical CP mixtures because of their high complexity.


Assuntos
Hidrocarbonetos Clorados , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Clorados/análise , Espectrometria de Massas , Parafina/análise
15.
Environ Pollut ; 292(Pt A): 118298, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34626702

RESUMO

There are large knowledge gaps concerning environmental levels and fate of many organic pollutants, particularly for chemicals of emerging concern in tropical regions of the Global South. In this study, we investigated the levels of chlorinated paraffins (CPs) and dechloranes in air and soil in rural, suburban, and urban regions in and around Dar es Salaam, Tanzania. Samples were also collected near the city's main municipal waste dumpsite and an electronic waste (e-waste) handling facility. In passive air samples, short chain CPs (SCCPs) dominated, with an average estimated concentration of 22 ng/m3, while medium chain CPs (MCCPs) had an average estimated concentration of 9 ng/m3. The average estimated air concentration of ∑dechloranes (Dechlorane Plus (DP) + Dechlorane 602 + Dechlorane 603) was three to four orders of magnitudes lower, 2 pg/m3. In soil samples, MCCPs dominated with an average concentration of 640 ng/g dw, followed by SCCPs with an average concentration of 330 ng/g dw, and ∑dechloranes with an average concentration of 0.9 ng/g dw. In both air and soil, DP was the dominating dechlorane compound. Urban pulses were observed for CPs and dechloranes in air and soil. CPs were in addition found in elevated levels at the municipal waste dumpsite and the e-waste handling facility, while DPs were found in elevated levels at the e-waste handling facility. This suggests that waste handling sites represent important emission sources for these pollutants. Investigations into seasonal trends and environmental fate of CPs and dechloranes showed that monsoonal rain patterns play a major role in governing air concentrations and mobility, particularly for the less volatile MCCPs and dechloranes. This study is the first to report levels of CPs in air from sub-Saharan Africa, and DP, Dechlorane 602, and Dechlorane 603 in soil from sub-Saharan Africa.


Assuntos
Hidrocarbonetos Clorados , Parafina , China , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Parafina/análise , Solo , Tanzânia
16.
Sci Total Environ ; 803: 150137, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34788941

RESUMO

In this study, eggs of black-tailed gull (Larus crassirostris), a top trophic level predator of marine ecosystem were, for the first time, monitored to assess the temporal and spatial trends of emerging pollutants in South Korea. Two Island regions, namely, Baekryeong-do (Site A) and Hong-do (Site B) were investigated from 2012 to 2018, and the total levels of short chain chlorinated paraffins (SCCPs), medium chain CPs (MCCPs), and organophosphate flame retardants (OPFRs) for both Site A and B were 1180-2931 and 694-2023 ng/g lipid weight (lw), 1287-4898 and 1034-3075 ng/g lw, and 203-499 and 233-409 ng/g lw, respectively. The time-trends of the concentration of pollutants showed an increasing tendency from 2012 to 2018, with the levels predicted to be doubled within three years, following the results of regression analysis. A shift in temporal-trends from shorter to longer chain CPs was noted, suggesting the effect of industrial-related contamination. Especially, significantly high levels of CPs and OPFRs were found in the site adjacent to China, which is reasonable as China is the largest producer and consumer of FRs and plasticizers worldwide. This study is valuable to understand the temporal increment of emerging pollutants as the alternatives of phased-out FRs and plasticizers, while raising the need for continuous environmental management.


Assuntos
Charadriiformes , Retardadores de Chama , Hidrocarbonetos Clorados , Animais , China , Ecossistema , Monitoramento Ambiental , Retardadores de Chama/análise , Hidrocarbonetos Clorados/análise , Organofosfatos , Parafina/análise
17.
Environ Res ; 204(Pt A): 111980, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34474033

RESUMO

The ubiquitous presence of legacy and emerging persistent organic pollutants (POPs) in the environmental matrices poses a potential hazard to the humans and creating public health concerns. The present study aimed to evaluate dioxins, dioxin-like polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and chlorinated paraffins (CPs) concentrations in serum of women (postpartum, pregnant and non-pregnant) from Northern Norway to better understand their exposure and contamination status as well as temporal trends across 2007-2009 (MISA 1) to 2019 (MISA 2). Sixty-two blood samples from the MISA 1 cohort and 38 samples from MISA 2 were randomly selected in this study (n = 100). Ninety samples from postpartum (MISA 1) and pregnant women (MISA 2) were randomly combined into 9 pools, with 9-11 individual samples contributing to each pool keeping the groups of pregnant and postpartum women. Remaining 10 samples from non-pregnant women (MISA 2) were allocated into separate group. Geometric mean, minimum and maximum were used to describe the serum concentrations of pooled POPs in MISA cohort. Mann-Whitney U test and independent sample t-test were applied for trend analysis of blood levels of POPs between MISA 1 and MISA 2. We found the serum concentrations of selected POPs in this study to be at lower range. Serum concentrations of dibenzo-p-dioxins (PCDDs) (p = 0.010), polychlorinated dibenzofurans (PCDFs) (p = 0.002), dioxins-like PCBs (p = 0.001), hexachlorobenzene (HCB) (p < 0.001) and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) (p = 0.002) were decreased between the studied time. In contrast, the serum concentrations of medium chain chlorinated paraffins showed an increasing trend between 2007 and 2009 and 2019 (p = 0.019). Our findings report a particular concern of emerging contaminant medium chain chlorinated paraffin exposure to humans. Future observational studies with repeated measurements of chlorinated paraffins in general populations worldwide and large sample size are warranted.


Assuntos
Dioxinas , Poluentes Ambientais , Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Estudos de Coortes , Dibenzofuranos Policlorados , Dioxinas/análise , Monitoramento Ambiental , Feminino , Humanos , Hidrocarbonetos Clorados/análise , Parafina , Praguicidas/análise , Bifenilos Policlorados/análise , Gravidez
18.
Chemosphere ; 287(Pt 3): 132344, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34826954

RESUMO

Chlorinated paraffins (CPs) are chemicals with multipurpose applications. Their global production has increased despite their adverse impacts on the environment and human health. In 2017, short-chain chlorinated paraffins (SCCPs) were listed as persistent organic pollutants (POPs) in the Stockholm Convention. Yet, specific exemptions were granted for their applications despite the recycling prohibition for products containing SCCPs. Therefore, we aimed to produce the first Brazilian inventory of SCCPs following its respective guidance to evaluate the applicability of the SCCP inventory guidance and to provide technical insights regarding SCCPs in the update of the Brazilian National Implementation Plan (NIP). Moreover, we performed a review of SCCP occurrence in Brazil to fulfil data gaps in the inventory development. We identified and consulted nationwide stakeholders and assessed foreign trade data of CPs and products that might contain CPs in relevant amounts. The Brazilian production of CPs was discontinued in 1994. However, CPs are still imported and used in the country. CPs have been mostly applied as plasticizers, flame retardants and lubricants in Brazil. The import of products containing CPs also pose a significant route of CP entrance into Brazil. Thus, the current end-of-life management of CP-containing products is a bottleneck towards the Convention implementation. The guidance application was feasible and useful despite the low engagement of stakeholders. To assess foreign trade of CPs and CP-containing products, we recommend the use of more specific tracking codes. Besides, the review of SCCP occurrence is not a demanded part for an inventory but was a useful complementation.


Assuntos
Hidrocarbonetos Clorados , Parafina , Brasil , China , Monitoramento Ambiental , Humanos , Hidrocarbonetos Clorados/análise , Parafina/análise
19.
J Hazard Mater ; 423(Pt A): 127010, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34474368

RESUMO

BTEX and chlorinated aliphatic hydrocarbons (CAHs) are the common pollutants found at contaminated sites, and natural attenuation (NA) of CAHs was widely observed where they coexist. In this work, the groundwater in a site co-contaminated with BTEX and CAHs was monitored for 1 year. The compositions and activities of the microfloras, especially dechlorinators and their relationships with the contaminants, geochemical properties, seasons and depth were evaluated. The results are consistent with the well-known NA conceptual model where CAHs are not able to stimulate the enrichment of dechlorinators alone, but BTEX does promote dechlorination. The higher temperature, rather than ORP in the deeper groundwater of the wet season became a key factor to promote the abundance of dechlorinators, but only when BTEX was available, indicating that the substrates from the BTEX biodegradation played an important role in the dechlorinator enrichment. The elevated ORP in the shallower groundwater exceeded the optimum conditions for reductive dechlorination and no significant seasonal variation of dechlorinators was found. The co-occurrence network revealed the cooperative interactions among the functional microfloras in which dechlorinators, BTEX degraders, and fermentative bacteria jointly promoted the dechlorination. These findings provided us a further understanding of the NA processes in a commingled plume.


Assuntos
Água Subterrânea , Hidrocarbonetos Clorados , Microbiota , Poluentes Químicos da Água , Biodegradação Ambiental , Solventes , Poluentes Químicos da Água/análise
20.
J Hazard Mater ; 422: 126813, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34399222

RESUMO

This study systematically investigates the formation of trichloronitromethane (TCNM) from 2 natural waters, 6 humic substances and 16 phenolic compounds during UV/monochloramine (UV/NH2Cl) followed by post-chloramination. Using 15N-NH2Cl as an isotope tracer, we found that 15N-TCNM accounted for 70.7-76.5% of total TCNM during UV/NH2Cl treated 2 natural waters, which was significantly higher than the proportion of 15N-TCNM in chloramination (NH2Cl alone). This is a direct evidence that NH2Cl, rather than the nitrogenous matters in waters, was the predominant nitrogen source of TCNM during UV/NH2Cl treatment. Phenol derivatives with meta-substituents and with electron-withdrawing groups facilitated the formation of TCNM precursors during UV/NH2Cl treatment. Significant correlations were found between Hammett constants (σ) of substituents and TCNM formation potentials. The formation mechanisms of TCNM were revealed using resorcinol as a representative phenolic compound. During UV/NH2Cl treatment, HO•, reactive chlorine species and reactive nitrogen species contributed to 28.1%, 29.0% and 19.4% of resorcinol degradation. Five nitro(so)-intermediates were identified as the main TCNM precursors. The formation pathways of TCNM were proposed. Alkaline pH was recommended to reduce the formation of TCNM precursors during UV/NH2Cl treatment.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cloraminas , Cloro , Desinfecção , Halogenação , Hidrocarbonetos Clorados , Poluentes Químicos da Água/análise
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