To understand human contamination by multi-trace elements (TEs) in electrical and electronic waste (e-waste) recycling site at Agbogbloshie, Accra in Ghana, this study analyzed TEs and As speciation ...in urine of e-waste recycling workers. Concentrations of Fe, Sb, and Pb in urine of e-waste recycling workers were significantly higher than those of reference sites after consideration of interaction by age, indicating that the recycling workers are exposed to these TEs through the recycling activity. Urinary As concentration was relatively high, although the level in drinking water was quite low. Speciation analysis of As in human urine revealed that arsenobetaine and dimethylarsinic acid were the predominant As species and concentrations of both species were positively correlated with total As concentration as well as between each other. These results suggest that such compounds may be derived from the same source, probably fish and shellfish and greatly influence As exposure levels. To our knowledge, this is the first study on human contamination resulting from the primitive recycling of e-waste in Ghana. This study will contribute to the knowledge about human exposure to trace elements from an e-waste site in a less industrialized region so far scantly covered in the literature.
► Exposure status of trace elements in e-waste recycling workers was assessed in Ghana. ► Concentrations of Fe, Sb, and Pb in urine of e-waste workers were significantly higher than those of the reference subjects. ► This study is the first to investigate human contamination arising from primitive recycling of e-waste arguably from Africa.
India has extensive production and usage of organochlorine pesticides (OCPs) for agriculture and vector control. Despite this, few data are available on the levels and distribution of OCPs in the ...urban atmosphere of India. Passive and active air sampling was therefore conducted between Dec 2006 and March 2007 in 7 metropolitan cities: New Delhi, Kolkata, Mumbai, Chennai, Bangalore, Goa, and Agra. Concentrations (pg·m−3) were as follows: HCHs 890−17000 (mean: 5400 ± 4110); DDTs 250−6110 (1470 ± 1010); chlordanes 290−5260 (1530 ± 790); endosulfans 240−4650 (1040 ± 610); and hexachlorobenzene 120−2890 (790 ± 510). HCHs observed in India appear to be the highest reported across the globe. Chlordanes and endosulfans are lower than levels reported from southern China. Passive sampling enabled within- and between-city variations to be assessed. As expected, paired-sample t-test analysis revealed higher regional than local variation. Comparisons with the limited data available from studies conducted in 1989 suggest general declines of HCHs and DDTs for most regions. γ-HCH dominated the HCH signal, reflecting widespread use of Lindane in India, although the isomeric composition in Kolkata suggests potential technical HCH use. High o,p′-/p,p′-DDT ratios in northern India indicate recent DDT usage. High HCB levels in the industrial areas of New Delhi and Kolkata indicate ongoing sources. Correlation between trans- and cis-chlordane implies ongoing usage. Endosulfan sulfate generally dominated the endosulfan signal, but high values of α/β-endosulfan at Chennai, Mumbai and Goa suggest ongoing usage. Backward trajectories were computed using the NOAA HYSPLIT model to trace the air mass history. Result shows local/regional sources of OCPs within India.
Zinc (Zn) plays important roles in various biological activities but there is little available information regarding its functions in spermatogenesis. In our current study, we further examined the ...role of Zn during spermatogenesis in the Japanese eel (Anguilla japonica). Human CG (hCG) was injected into the animals to induce spermatogenesis, after which the concentration of Zn in the testis increased in tandem with the progression of spermatogenesis. Staining of testicular cells with a Zn-specific fluorescent probe revealed that Zn accumulates in germ cells, particularly in the mitochondria of spermatogonia and spermatozoa. Using an in vitro testicular organ culture system for the Japanese eel, production of a Zn deficiency by chelation with N,N,N',N'-tetrakis (2-pyridylemethyl)ethylenediamine (TPEN) caused apoptosis of the germ cells. However, this cell death was rescued by the addition of Zn to the cultures. Furthermore, an induced deficiency of Zn by TPEN chelation was found to inhibit the germ cell proliferation induced by 11-ketotestosterone (KT), a fish specific androgen, 17α,20β-dihydroxy-4-pregnen-3-one (DHP), the initiator of meiosis in fish, and estradiol-17β (E2), an inducer of spermatogonial stem-cell renewal. We also investigated the effects of Zn deficiency on sperm motility and observed that TPEN treatment of eel sperm suppressed the rate and duration of their motility but that co-treatment with Zn blocked the effects of TPEN. Our present results thus suggest that Zn is an essential trace element for the maintenance of germ cells, the progression spermatogenesis, and the regulation of sperm motility.
As an animal familiar to humans, cats are considered to be sensitive to chemicals; cats may be exposed to polychlorinated biphenyls (PCBs) and decabromodiphenyl ether (BDE-209) from indoor dust, ...household products, and common pet food, leading to adverse endocrine effects, such as thyroid hormone dysfunction. To elucidate the general biological effects resulting from exposure of cats to PCBs and PBDEs, cats were treated with a single i.p. dose of a principal mixture of 12 PCBs and observed for a short-term period. Results revealed that the testis weight, serum albumin, and total protein of the treated group decrease statistically in comparison with those in the control group. The negative correlations suggested that the decrease in the total protein and albumin levels may be disturbed by 4'OH-CB18, 3'OH-CB28 and 3OH-CB101. Meanwhile, the serum albumin level and relative brain weight decreased significantly for cats subjected to 1-year continuous oral administration of BDE-209 in comparison to those of control cats. In addition, the subcutaneous fat as well as serum high-density lipoprotein (HDL) and triglycerides (TG) levels increased in cats treated with BDE-209 and down-regulation of stearoyl-CoA desaturase mRNA expression in the liver occurred. These results suggested that chronic BDE-209 treatment may restrain lipolysis in the liver, which is associated with lipogenesis in the subcutaneous fat. Evidence of liver and kidney cell damage was not observed as there was no significant difference in the liver enzymes, blood urea nitrogen and creatinine levels between the two groups of both experiments. To the best of our knowledge, this is the first study that provides information on the biochemical effects of organohalogen compounds in cats. Further investigations on risk assessment and other potential health effects of PCBs and PBDEs on the reproductive system, brain, and lipid metabolism in cats are required.
The presence of antimicrobials, antimicrobial-resistant bacteria (ARB), and the associated antimicrobial resistance genes (ARGs) in the environment is a global health concern. In this study, the ...concentrations of 25 antimicrobials, the resistance of Escherichia coli (E. coli) strains in response to the selection pressure imposed by 15 antimicrobials, and enrichment of 20 ARGs in E. coli isolated from hospital wastewaters and surface waters were investigated from 2016 to 2018. In hospital wastewaters, clarithromycin was detected at the highest concentration followed by sulfamethoxazole and sulfapyridine. Approximately 80% of the E. coli isolates were resistant, while 14% of the isolates exhibited intermediate resistance against the tested antimicrobial agents. Approximately 61% of the examined isolates were categorized as multidrug-resistant bacteria. The overall abundance of phenotypes that were resistant toward drugs was in the following order: β-lactams, tetracycline, quinolones, sulfamethoxazole/trimethoprim, aminoglycosides, and chloramphenicol. The data showed that the E. coli isolates frequently harbored blaTEM, blaCTX-M, tetA, qnrS, and sul2. These results indicated that personal care products were significantly associated with the presence of several resistant phenotypes and resistance genes, implying their role in co-association with multidrug resistance. Statistical analysis also indicated a disparity specific to the site, treatment, and year in the data describing the prevalence of ARB and ARGs and their release into downstream waters. This study provides novel insights into the abundance of antimicrobial, ARB and ARGs in Sri Lanka, and could further offer invaluable information that can be integrated into global antimicrobial resistance databases.
•Clarithromycin was the most abundant antimicrobial found in hospital wastewaters.•94% of E. coli were fully or intermediately resistant to the tested drugs.•61% of the bacterial isolates were categorized as multidrug-resistant.•E. coli isolates frequently harbored blaTEM, blaCTX-M, tetA, qnrS, and sul2.•PCPs likely facilitated the maintenance and persistence of ARB and ARGs.
Dioxin-Responsive Chemical-Activated LUciferase gene eXpression assay (DR-CALUX) was applied to assess the total toxic activity of the mixture of PAHs and related compounds as well as dioxin-related ...compounds in road dust from urban areas of Hanoi, Vietnam. Road dust from Hanoi contained significantly higher DR-CALUX activities (3 to 39, mean 20ng CALUX-TEQ/g dw) than those from a rural site (2 to 13, mean 5ng CALUX-TEQ/g dw). The total concentrations of 24 major PAHs (Σ24PAHs) in urban road dust (0.1 to 5.5, mean 2.5μg/g dw) were also 6 times higher than those in rural road dust (0.08 to 1.5, mean 0.4μg/g dw). Diagnostic ratios of PAHs indicated vehicular engine combustion as the major PAH emission source in both sites. PAHs accounted for 0.8 to 60% (mean 10%) and 2 to 76% (mean 20%) of the measured CALUX-TEQs in road dust for Hanoi the rural site, respectively. Benzob-/benzokfluoranthenes were the major TEQ contributors among PAHs, whereas DRCs contributed <0.1% to CALUX-TEQs for both rural and urban sites. These results suggest TEQ contribution of other aryl hydrocarbon receptor agonists in road dust. Significant PAH concentrations in urban dust indicated high mutagenic and carcinogenic potencies. Estimated results of incremental life time cancer risk (ILCR) indicated that Vietnamese populations, especially those in urban areas such as Hanoi, are potentially exposed to high cancer risk via both dust ingestion and dermal contact. This is the first study on the exposure risk of AhR agonists, including PAHs and DRCs, in urban road dust from a developing country using a combined bio-chemical analytical approach.
•First assessment of total AhR-mediated toxic activities in road dust using DR-CALUX.•PAHs known as carcinogens were found at high levels in Hanoi.•PAHs contributed only 0.8–76% to AhR agonist activities in road dust.•Exposure to PAHs in road dust may pose high cancer risk for Hanoi residents.
Polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs) might disrupt thyroid function. However, there is no clear evidence of PCB exposure disrupting thyroid hormone (TH) ...homeostasis in dogs and cats. The present study conducted in vivo experiments to evaluate the effects of a mixture of 12 PCB congeners (CB18, 28, 70, 77, 99, 101, 118, 138, 153, 180, 187 and 202, each congener 0.5 mg/kg BW, i.p. administration) on serum TH levels in male dogs (Canis lupus familiaris) and male cats (Felis silvestris catus). In PCB-exposed dogs, the time courses of higher-chlorinated PCBs and L-thyroxine (T4)-like OH-PCBs (4-OH-CB107 and 4-OH-CB202) concentrations were unchanged or tended to increase, whereas those of lower-chlorinated PCBs and OH-PCBs tended to decrease after 24 h. In PCB-exposed cats, concentrations of PCBs increased until 6 h and then remained unchanged. The levels of lower-chlorinated OH-PCBs including 4′-OH-CB18 increased until 96 h and then decreased. In PCB-exposed dogs, free T4 concentrations were higher than those in the control group at 48 and 96 h after PCB administration and positively correlated with the levels of T4-like OH-PCBs, suggesting competitive binding of T4 and T4-like OH-PCBs to a TH transporter, transthyretin. Serum levels of total T4 and total 3,3′,5-triiodo-L-thyronine (T3) in PCB-exposed dogs were lower than in the control group at 24 and 48 h and negatively correlated with PCB concentrations, implying that PCB exposure enhanced TH excretion by increasing TH uptake and TH conjugation enzyme activities in the dog liver. In contrast, no obvious changes in TH levels were observed in PCB-exposed cats. This could be explained by the lower levels of T4-like OH-PCBs and lower hepatic conjugation enzyme activities in cats compared with dogs. Different effects on serum TH levels in PCB-exposed dogs and cats are likely to be attributable to species-specific PCB and TH metabolism.
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•Effects of PCBs on serum thyroid hormone (TH) levels in dogs and cats were evaluated.•Total T4 and T3 levels decreased and free T4 levels increased in PCB-exposed dogs.•No change in TH levels was observed in PCB-exposed cats.•Different effects on TH levels in dogs and cats may be due to PCB and TH metabolism.
We determined the contamination status and accumulation profiles of polychlorinated biphenyls (PCBs), hydroxylated PCB congeners (OH-PCBs), polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs ...(OH-PBDEs), methoxylated PBDEs (MeO-PBDEs), and bromophenols (BPhs) in serum from e-waste recycling workers and residents near a coastal area in India. Residue levels of penta- to octa-chlorinated PCBs, penta- to octa-chlorinated OH-PCBs, 6MeO-BDE47, 6OH-BDE47, and 2,4,6-tri-BPh in serum from residents living near the coastal area were significantly higher than those in serum from e-waste recycling workers. Residue levels of tri- to tetra-chlorinated PCBs, tri- to tetra-chlorinated OH-PCBs, PBDEs, octa-brominated OH-PBDEs, and tetra-BPhs in serum from e-waste recycling workers were higher than those in serum from residents living near the coastal area. Principal component analysis revealed that residents living near the coastal area and e-waste recycling workers had different serum profiles of chlorinated and brominated compounds.
► Analysis of levels of PCBs, PBDEs, and their metabolites in serum of Indians. ► Profiles of chlorinated and brominated compound differed between study populations. ► High PCB, 3Br BPh, 4Br OH-PBDE, and MeO-PBDE levels suggest high fish consumption. ► High 8Br- and 9Br-PBDE, 8Br-OH-PBDE, and 4Br-BPh levels indicate e-waste exposure.
India is of prime interest due to the large past and ongoing use of pesticidal persistent organic pollutants (POPs). Rapid dissipation of POPs to the atmosphere in the tropical climate of India ...infers an atmospheric outflow of these chemicals. Yet data on POPs in the atmosphere of India are sparse. Passive air samplers consisting of polyurethane foam disks were therefore deployed concurrently at 18 locations and exposed for 6 weeks from July 30, 2006, to September 26, 2006, along the coastal length of India to screen for POPs in the atmosphere. The sampling sites were selected to form categories of urban, rural, and background (mangrove/wetlands) locations. Derived air concentrations (pg/m3) ranged as follows: the sum of 28 PCB congeners, 120−1080; DDTs, 16−2950; HCHs, 66−5400; chlordanes, 9−921; endosulfans, 0.45−1120; and the sum of 9 PBDE congeners, 1−181. The highest levels of all the detected POPs (except endosulfan) were observed at the urban sites, indicating the dominant areas of usage and emissions. An urban−rural composition fractionation of PCBs indicates their atmospheric movement. The γ-HCH levels were more than double those of α-HCH, indicating the sporadic use of lindane. DDT concentrations were elevated, at levels comparable to China, but with much higher percentages of p,p′-DDE, reflecting a more ‘weathered’ feature. Although no dicofol use was recorded in India, the o,p′-/p,p′-DDT ratios were observed to be even higher than in China. Chlordanes showed high trans-/cis-chlordane (TC/CC) ratios, indicative of the current use of technical chlordane and a contribution from heptachlor usage.
Canis lupus familiaris (domestic dog) possess a high capacity to metabolize higher-chlorinated polychlorinated biphenyls (PCBs) to thyroid hormone (TH)-like hydroxylated PCB metabolites (OH-PCBs). As ...a result, the brain could be at high risk of toxicity caused by OH-PCBs. To evaluate the effect of OH-PCBs on dog brain, we analyzed OH-PCB levels in the brain and the metabolome of the frontal cortex following exposure to a mixture of PCBs (CB18, 28, 70, 77, 99, 101, 118, 138, 153, 180, 187, and 202). 4-OH-CB202 and 4-OH-CB107 were major OH-PCBs in the brain of PCB-exposed dogs. These OH-PCBs were associated with metabolites involved in urea cycle, proline-related compounds, and purine, pyrimidine, glutathione, and amino-acid metabolism in dog brain. Moreover, adenosine triphosphate levels in the PCBs exposure group were significantly lower than in the control group. These results suggest that OH-PCB exposure is associated with a disruption in TH homeostasis, generation of reactive oxygen species, and/or disruption of oxidative phosphorylation (OXPHOS) in brain cells. Among them, OXPHOS disturbance could be associated with both disruptions in cellular amino-acid metabolism and urea cycle. Therefore, an OXPHOS activity assay was performed to evaluate the disruption of OXPHOS by OH-PCBs. The results indicated that 4-OH-CB107 inhibits the function of Complexes III, IV, and V of the electron transport chain, suggesting that 4-OH-CB107 inhibit these complexes in OXPHOS. The neurotoxic effects of PCB exposure may be mediated through mitochondrial toxicity of OH-PCBs in the brain.
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•4-OH-CB202 and 4-OH-CB107 showed strong transfer to the dog brain.•OH-PCBs were associated with metabolites involved in urea cycle in dog brain.•OH-PCB exposure was suggested with a disruption of OXPHOS in brain cells.•4-OH-CB107 inhibited the functions of mitochondrial complex III, IV, and V.
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