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Levels of polychlorinated biphenyls, organochlorine pesticides, mercury, cadmium, copper, selenium, arsenic, and zinc in the harbour seal, Phoca vitulina, in Norwegian waters.
1990
Skaare J.U. | Markussen N.H. | Norheim G. | Haugen S. | Holt G.
Trends in organochlorine and mercury levels in gannet eggs.
1990
Newton I. | Haas M.B. | Freestone P.
PCBs [polychlorinated biphenyls], dioxins and furans in hooded merganser (Lophodytes cucullatus), common merganser (Mergus merganser) and mink (Mustela vison) collected along the St. Maurice River near La Tuque, Quebec.
1996
Champoux L.
Microbiological remediation of waste-oil polluted soils -Ecotoxicological and toxicological considerations.
1994
Rippen G. | Held T. | Ripper P.
A waste-oil contaminated site situated near a river is supposed to be cleaned-up by means of different but complementary methods. On the basis of a research project, target values have been developed in close cooperation between the participant parties for the saturated and the unsaturated soil layers. The clean-up targets are introduced and discussed.
Afficher plus [+] Moins [-]β-Glucosidases as dominant dose-dependent regulators of Oryza sativa L. in response to typical organic pollutant exposures
2022
Shao, Zexi | Liu, Na | Wang, Wei | Zhu, Lizhong
Understanding the metabolic defense and compensation to maintain homeostasis is crucial for assessing the potential health risk of organic pollutants in crops. Currently, limited understanding is available regarding the targeted metabolic pathways and response mechanism under contaminant stress. This study showed that ciprofloxacin (CIP) at the environmental concentrations (1, 5, 25, 50 mg/L) did not significantly inhibit growth or cause severe oxidative damage to rice (Oryza sativa L.). Instead, the increment in CIP concentration induced a series of sequential metabolic disorders, which were characterized predominantly by primary and secondary metabolic disturbances, including phenylpropanoid biosynthesis, the carbohydrate, lipid and amino acid metabolism. After CIP in vivo exceeded a certain threshold level (>0.29 mg/g dry weight), β-glucosidases (BGLUs) mediated the transition from the activation of the genes related to phenylpropanoid biosynthesis to the inhibition of the genes related to carbohydrate metabolism in rice. In particular, starch and sucrose metabolism showed the most profound perturbation stressed by environmental concentrations of CIP (5 mg/L) and other tested organic pollutants (10 μg/L of tricyclazole, thiamethoxam, polybrominated diphenyl ethers, and polychlorinated biphenyls). Besides, the key genes encoding endoglucanase and BGLU were significantly downregulated (|log₂FC| > 3.0) under 100 μg/L of other tested organic pollutants, supporting the transition from the activation of secondary defense metabolism to the disruption of primary energy metabolism. Thus, in addition to bioaccumulation, changes in BGLU activity and starch and sucrose metabolism can reflect the potential adverse effects of pollutants on rice. This study explained the stepwise metabolic and transcriptional responses of rice to organic pollutants, which provided a new reference for the comprehensive evaluation of their environmental risks.
Afficher plus [+] Moins [-]Halogenated flame retardants in Irish waste polymers: Concentrations, legislative compliance, and preliminary assessment of temporal trends
2022
Drage, Daniel | Sharkey, Martin | Al-Omran, Layla Salih | Stubbings, William A. | Berresheim, Harald | Coggins, Marie | Rosa, André Henrique | Harrad, Stuart
Halogenated flame retardants (HFRs) were measured in 470 waste plastic articles from Ireland between 2019 and 2020. We identified articles containing concentrations of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), and tetrabromobisphenol-A (TBBP-A) exceeding European Union limits. Enforcement of existing limits of 1000 mg/kg will render an estimated 3.1% (2800 t) of articles in the waste categories studied unrecyclable, increasing to: 4.0, 4.9, and 5.6% if limits were reduced to 500, 200, and 100 mg/kg respectively. Meanwhile, enforcing limits of 1,000, 500, 200, and 100 mg/kg will respectively remove 78, 82, 84, and 85% of PBDEs, HBCDD, and TBBP-A present in such waste. Other FRs targeted were detected infrequently and predominantly at very low concentrations. However, 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBP-TAZ) was detected in 3 display/IT product samples at 14,000 to 32,000 mg/kg, indicating elevated concentrations of FRs used as alternatives to PBDEs and HBCDD, will likely increase in future. Comparison with data for Ireland in 2015–16, revealed concentrations and exceedances of limits for PBDEs, HBCDD, and TBBP-A were similar or have declined. For end-of-life vehicle fabrics and foams, HBCDD and ΣPBDE concentrations declined significantly (p < 0.05) since 2015–16. Moreover, ΣPBDE concentrations in waste small domestic appliances are significantly lower in 2019–20, with a similarly significant decline for TBBP-A in waste IT and telecommunications articles. In contrast, HBCDD concentrations in waste extruded polystyrene increased significantly between 2015–16 and 2019–20. For other waste categories studied, no statistically significant temporal trends are evident (p > 0.05). Fewer samples exceeded PBDE and HBCDD limits in 2019–20 (7.8%) than 2015–16 (8.7%), while exceedances for TBBP-A fell from 2.4% in 2015–16 to 0.57% in 2019–20. While comparison between the 2015–16 and 2019-20 datasets provide a preliminary indication of changes, further monitoring is required if the impact of legislation designed to eliminate HFRs from the waste stream is to be fully evaluated.
Afficher plus [+] Moins [-]Associations between polybrominated diphenyl ethers (PBDEs) levels in adipose tissues and female menstrual cycle and menstrual bleeding duration in Shantou, China
2022
Shi, Xiaoling | Wang, Xin | Peng, Lin | Chen, Yebin | Liu, Caixia | Yang, Qingtao | Wu, Kusheng
The endocrine-disrupting effects of human exposure to polybrominated diphenyl ethers (PBDEs) have been studied, but their associations with menstrual status were not clearly clarified. This study was to evaluate the associations between PBDE levels in adipose tissues and the menstrual cycle and menstrual bleeding duration alteration. A total of 298 female cases undergoing surgery were recruited from two hospitals in Shantou, China. Demographic, clinical, and pathological information were collected, and adipose tissues were obtained during mammary or abdominal surgery. Gas chromatography with mass spectrometry was used to analyze 14 PBDE congeners in the adipose samples. The associations between PBDE levels and menstrual cycle (MC) and menstrual duration (MD) were analyzed by logistic regression models, estimating odds ratios (ORs) and 95% confidence intervals (CIs). BDE-153 had the highest level in the adipose samples, followed by BDE-209, BDE-183 and BDE-47. Compared with referents, median levels of BDE-47, -71, −153, −183 were higher in women with MC > 30 days (all P < 0.05); BDE-47, -153, −183, −209 were also higher in women with MD > 5.5 days (all P < 0.05). After adjusted for age and parity, BDE-47, -71, −153, −183 were associated with prolonged MC (OR = 1.20, 1.15, 1.12, 1.11, respectively, all P < 0.05) in the logistic regression models; and BDE-47, -153, −183, −209 were associated with the prolonged MD (OR = 1.13, 1.09, 1.10, 1.11, respectively, all P < 0.05). Several individual PBDE congeners in female adipose were found associated with prolonged menstrual cycle and menstrual duration. PBDEs may influence reproductive health of women by altering menstrual status.
Afficher plus [+] Moins [-]Associations between organophosphate esters concentrations and markers of liver function in US adolescents aged 12–19 years: A mixture analysis
2022
Li, Ruiqiang | Zhan, Wenqiang | Ren, Jingyi | Gao, Xian | Huang, Xin | Ma, Yuxia
Liver disease has become a growing health burden, and little is known about the impairment of liver function caused by exposure to organophosphate esters (OPEs) in adolescents aged 12–19 years in the United States. To investigate the relationship between urinary metabolites of OPEs including diphenyl phosphate (DPHP), bis(1,3-dichloro-2-propyl) phosphate (BDCPP), bis(1-chloroethyl) phosphate (BCPP), bis(2-chloroethyl) phosphate (BCEP), and dibutyl phosphate (DBUP) and liver function in US adolescents aged 12–19 years. Liver function tests (LFTs) include aspartate aminotransferase (AST), albumin (ALB), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), total bilirubin (TBIL), total protein (TP), and AST/ALT. Meanwhile, potential confounding and interaction effects were assessed. The study sample included 592 adolescents aged 12–19 from two consecutive NHANES cycles (2011–2012, 2013–2014). A composite statistical strategy combining traditional linear regression with advanced multi-pollutant models quantile based g-computation (QGC) and eXtreme Gradient Boosting (XGBoost) regression was used to analyze the joint effects of multiple OPEs on liver function indicators, and to describe the interaction between different OPEs in detail. 592 adolescent participants were 15 (14–17) years old, with similar numbers of males and females (304 vs. 288). The analysis results showed that (1) in the linear regression model, individual DPHP, BCEP exposure and ALP changes, BCEP and AST/ALT changes were positively associated. DPHP, BDCPP were negatively associated with TP changes. (2) The combined effects of various OPEs on ALB, ALT, ALP, GGT, TBIL, TP, and AST/ALT were statistically significant. (3) There is no potential interaction between different OPEs. Several OPEs and their combinations are closely related to the 8 LFT indicators. In addition, data suggest that exposure to OPEs in adolescents may be associated with liver damage. Due to limited evidence in the literature and potential limitations of the current study, our findings require more studies to confirm.
Afficher plus [+] Moins [-]Trophic transfer of methylmercury and brominated flame retardants in adjacent riparian and aquatic food webs: 13C indicates biotransport of contaminants through food webs
2022
Wu, Xiaodan | Chen, Laiguo | Li, Xiaoyun | Cao, Xingpei | Zheng, Xiaobo | Li, Ronghua | Zhang, Jia'en | Luo, Xiaojun | Mai, Bixian
Biomagnification of persistent toxic substances (PTSs) in food chains is of environmental concern, but studies on biotransport of PTSs across aquatic and riparian food chains are still incomplete. In this study, biomagnification of several PTSs including methylmercury (MeHg), polybrominated diphenyl ethers (PBDEs), and 1,2-bis (2,4,6-tribromophenoxy) ethane (BTBPE) was investigated in adjacent aquatic and riparian food webs. Concentrations of MeHg and PBDEs ranged from 2.37 to 353 ng/g dry weight (dw) and not detected (Nd) to 65.1 ng/g lipid weight (lw) in riparian samples, respectively, and ranged from Nd to 705 ng/g dw and Nd to 187 ng/g lw in aquatic samples, respectively. Concentrations of MeHg were significantly correlated with δ¹³C (p < 0.01) rather than δ¹⁵N (p > 0.05) values in riparian organisms, while a significant correlation was observed between concentrations of MeHg and δ¹⁵N (p < 0.01) in aquatic organisms. Biomagnification factors (BMFs) and trophic magnification factors (TMFs) of PBDE congeners were similar in riparian and aquatic food webs, while BMFs and TMFs of MeHg were much higher in aquatic food web than those in riparian food web. The results indicate the biotransport of MeHg from aquatic insects to terrestrial birds, and δ¹³C can be a promising ecological indicator for biotransport of pollutants across ecosystems.
Afficher plus [+] Moins [-]Distribution and source of and health risks associated with polybrominated diphenyl ethers in dust generated by public transportation
2022
Jin, Mantong | Zhang, Shunfei | Ye, Nanxi | Zhou, Shanshan | Xu, Ziyu
Carcinogenic and neurotoxic polybrominated diphenyl ethers (PBDEs) are environmentally ubiquitous and have been widely investigated. However, little is understood regarding their pollution status, sources, and potential risk to persons in public transportation microenvironments (PTMs). We collected 60 dust samples from PTMs and then selected four materials typical of bus interiors to determine the sources of PBDEs in dust using principal component analysis coupled with Mantel tests. We then evaluated the risk of PBDEs to public health using Monte Carlo simulations. We found that PBDE concentrations in dust were 2-fold higher in buses than at bus stops and that brominated diphenyl ether (BDE)-209 was the main pollutant. The number of buses that passed through a bust stop contributed to the extent of PBDE pollution, and the primary potential sources of PBDEs in dust were plastic handles and curtains inside buses; BDE-209 and BDE-154 were the main contributors of pollution. We found that health risk was 8-fold higher in toddlers than in adults and that the reference doses of PBDEs in dust were far below the United States Environmental Protection Agency limits. Our findings provide a scientific basis that may aid in preventing PBDE pollution and guiding related pollution management strategies in PTMs.
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