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1.
Polychlorinated biphenyls (PCBs) are a class of persistent organic pollutants that were widely used in the mid-20th century. Though their production and use was banned by most countries several decades ago, the general population continues to be exposed due to the persistence and bioaccumulation of PCBs. A number of human epidemiological studies have assessed the relationship between environmental PCB exposure and markers of male reproductive health, namely semen quality parameters (sperm concentration, motility, and morphology), sperm DNA integrity (DNA damage or chromatin fragmentation), and circulating reproductive hormone levels. Despite a wide range of study designs and locations, measurement methods, and PCB exposure levels, reports of inverse associations between PCBs and sperm motility have been consistent which may suggest a lack of exposure threshold for a PCB-related effect on sperm motility. Several studies have also reported inverse associations between PCBs and circulating testosterone levels in men, though the specific form of testosterone (i.e. total, bound, or free testosterone) associated with exposure has not been fully consistent between studies. In conclusion, although PCBs are no longer used and can be considered a legacy chemical, concerns regarding altered male fertility in relation to PCBs remain due to the existing human data demonstrating inverse associations with markers of male reproductive function coupled with recent evidence for continued population exposure.  相似文献   

2.
In studies of the potential health effects of background-level exposure to organochlorine compounds (e.g., polychlorinated biphenyls, polychlorinated dibenzodioxins, and polychlorinated dibenzofurans), investigators have often measured either polychlorinated biphenyls or polychlorinated dibenzodioxins/polychlorinated dibenzofurans—but not both. We measured polychlorinated biphenyls (including specific non-, mono-, and di-ortho congeners) and specific polychlorinated dibenzodioxins/dibenzofurans among 63 Canadian blood donors. Levels of these compounds were, in general, fairly correlated. For example, Pearson's correlation coefficient between log total polychlorinated biphenyl and log total polychlorinated dibenzodioxins was .52. These results suggest that in epidemiologic studies of health effects of background-level exposures to these compounds, the quantitative dose-response relation observed for a given compound (or class of compounds acting through a similar mechanism) may easily be miscalibrated or confounded.  相似文献   

3.
This paper describes the concentrations of seven polychlorinated biphenyls (PCBs) in bottled drinking water samples that were collected over 1 year from Mexico City in two sizes (1.5 and 19 L), using gas chromatography with an electron capture detector. PCBs 28 (0.018–0.042 μg/L), 52 (0.006–0.015 μg/L) and 101 (0.001–0.039 μg/L) were the most commonly found and were present in the majority of the samples. However, total concentrations of PCBs in bottled drinking water (0.035–0.039 μg/L) were below the maximum permissible level of 0.50 μg/L stated in Mexican regulations and probably do not represent a hazard to human health. PCBs were detectable in all samples and we recommend a monitoring program be established to better understand the quality of drinking bottled water over time; this may help in producing solutions for reducing the presence of organic contaminants.  相似文献   

4.
Blood samples were collected from 28 mothers and from 38 school-aged children from Michigan farms on which there were polychlorinated biphenyl (PCB) -contaminated silos. The samples were analyzed for PCBs and other contaminants, including polybrominated biphenyls (PBBs) and dichlorodiphenyl trichloroethane (p,p′-DDT + p,p′-DDE) via packed column gas chromatography. The PCBs were quantified, using the Webb-McCall method, with Aroclors 1016 and 1260 used as reference standards. Approximately 42% of the children had serum PCB levels above the detection limit of 3.0 ng/ml. The values ranged from 3.1 to 23.3 ng/ml, with a mean of 6.8 ng/ml. In contrast, PCBs were detected in 86% of the mothers. The mean serum concentration was somewhat higher for the mothers (9.6 ng/ml), but the range was similar to that found for the children. PBBs were not detected in any of the children, but were present in trace amounts in 25% of the mothers. Conversely, DDT was present in 66% of the children and 93% of the mothers. As with PCBs, DDT concentrations were somewhat higher in the mothers. DDE accounted for 89% of the total DDT in serum. Various potential sources of exposure were evaluated as possible determinants of serum PCB levels, using hierarchical multiple regression. Years of residence on a silo farm and consumption of PCB-contaminated Great Lakes fish both accounted for significant portions of the variance in maternal serum PCB levels. Exposure via breast-feeding explained a large and highly significant proportion of the variance in the children's serum PCB concentrations, suggesting that breast milk was the primary source of PCB exposure for these children. Years of residence on a silo farm also explained a significant proportion of the variance in children's serum PCBs. The pattern of Webb-McCall elution peaks was similar in the children and mothers and closely resembled patterns observed in other Michigan cohorts exposed to PCBs through consumption of PCB-contaminated Great Lakes fish.  相似文献   

5.
6.
Two groups of rainbow trout were caged in the River Po upstream and downstream of the confluence with the River Lambro, a relatively small tributary which drains the most industrialized and urbanized area of the entire basin. Fish were analyzed for PCB concentration at the start of the experiment and after 7, 15, and 30 days of exposure. The results demonstrate that the emission of the River Lambro represents an important point source of PCBs to the River Po and that part of the transported load is readily bioavailable, since caging virtually excluded trophic transfers. On the basis of PCB levels measured in downstream trout, the steady-state concentration and the congener pattern were predicted by means of a computer program. These projections were compared with published data obtained with native fish caught downstream from the River Lambro.  相似文献   

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8.
[目的]以加速溶剂萃取技术和稳定性同位素稀释法、气相色谱负化学源(NCI)质谱法,建立食品中指示性多氯联苯单体(PCBs)测定方法。[方法]样品中加入^13C12取代同位素,经加速溶剂萃取、浓缩、混合硅胶柱与氧化铝柱净化后,以GC—MS-NCI分析浓缩液,进行选择离子监测,以内标法的相对响应因子定量。[结果]各单体在20~2000ng/mL内重复测定时,相对响应因子的相对标准偏差(RSD)2.2%~19.3%,符合线性要求;检测限0.003~38.6μg/kg,同时低于5个氯原子的PCBs单体,其NCI法灵敏度小于EI法,当超过5个氯原子时,NCI法灵敏度为EI法的1.1~67.4倍;以干贝与肉松为加标基质进行准确度和精密度试验,干贝加标水平为0.5、1.0μg/kg,肉松为0.5μg/kg。测定国家限量标准规定的PCBs各单体时,其回收率和RSD分别在72.1%~129%和4.1%~18.5%。[结论]本法测定PCBs的灵敏度较高,可满足国家限量标准的要求。  相似文献   

9.
Organochlorine (OC) concentrations in surface sediment, snails (Lymnea sp.), and two freshwater fish species (grayling, Thymallus arcticus; and lake trout, Salvelinus namaycush) from four lakes in the US Arctic were determined. In surface sediment, chlorinated benzenes (including hexachlorobenzene, HCB), and p,p′-DDT were the primary analytes detected (max = 0.7 ng/g dry wt), while individual polychlorinated biphenyl (PCB) congeners were always below 0.1 ng/g. A wider range of compounds and higher concentrations were found in lake trout, the top predatory fish species in the same lakes. The concentration ranges for hexachlorocyclohexanes (HCHs), chlordane-related compounds (CHLORs), DDTs, and PCBs in lake trout and grayling were similar to those reported for other arctic freshwater fish (1–100 ng/g wet wt), but one to two orders of magnitude lower than Great Lakes salmonids. Nitrogen isotope analysis confirmed that differences in OC concentrations between grayling and lake trout are explained partly by differences in food web position. Received: 30 August 1996/Accepted: 24 July 1997  相似文献   

10.
To evaluate the potential for using domestic animals in the surveillance of environmental exposures, we collected serum samples for polychlorinated biphenyl (PCB) analysis from nine dogs in Monroe County, Indiana, where people had been shown to have been exposed to PCBs. Nine dogs in Atlanta, Georgia, served as comparisons. Results indicated that canine serum PCB levels in contaminated areas (median = 3.0 ppb) tend to be greater than those in uncontaminated areas (median = 1.7 ppb [p = .06, Mann-Whitney U test]). This finding suggests that pet dogs may serve as sentinels of human exposure to enviromental PCB contamination.  相似文献   

11.
12.
In order to gain comprehensive understanding of status, properties and sources of PCBs pollution at an industrial area in Shanghai, PM10 were collected during the period November 2004–September 2005. The results showed that the mean value of total PCBs in the industrial area was 2,017.22 pg m−3. Three dioxin-like PCB congeners had a mean value of TEQ of 0.24 pg-TEQ m−3. The concentrations of PCBs at all sites were higher in colder months than in warmer months. ΣPCB concentrations were correlated positively with SO2, NO2 and OCPs, while negatively with polycyclic aromatic hydrocarbons (PAHs), ambient temperature, rainfall and wind speed. It could be concluded that the area had been contaminated by PCBs from a local source.  相似文献   

13.
The levels of PCBs and PCB methyl sulphone metabolites were determined in the blubber of six species of cetaceans that originated from the Irish Sea and the Aegean Sea (Mediterranean). Burdens ranging from 2.80 to 27.80 μg g−1 (lipid weight) total PCBs and 0.03 to 0.58 μg g−1 (lipid weight) total methyl sulphones were recorded. The highest cetacean methyl sulphone burden (0.58 μg g−1) was in an Irish Sea harbor porpoise (Phocoena phocoena). Methyl sulphone isomer formation capacity, as determined by PCB:MSF ratios, varied considerably between species as follows: harbour porpoise (1:10) > pilot whale (Globicephalus melas), white-sided dolphin (Lagenorhyncus acutus) (1:50) > common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), and striped dolphin (Stenella coerueoalba), (1:100), and was related to interspecific variation in PCB methyl sulphone formation capacity. Received: 3 April 1997/Accepted: 3 January 1998  相似文献   

14.
Few studies have been conducted to investigate the polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in freshwater since the volume of water needed for dioxin analysis is large. In this study, 19 water samples from the middle reaches of the Yangtze River were analysed for the levels of PCDD/Fs and dioxin-like PCBs (dl-PCBs). The results showed that the concentration ranges of PCDD/Fs and dl-PCBs were 0.6–8.5 and 2.0–15.8 pg/L, respectively, which were relatively low compared with those reported in the literature. The WHO-TEQ concentration range of dioxins was 0.002–0.040 pg/L. The PCA results indicated that the main sources of PCDD/Fs may be the applications of pentachlorophenol or sodium pentachlorophenate and domestic wood and coal burning. For dl-PCBs, domestic wood burning and coal burning were the main sources.  相似文献   

15.

Background

Hydroxylated polychlorinated biphenyls (OH-PCBs), unlike PCBs, are in general readily excreted yet are still detected in humans and animals. Active transport of OH-PCBs across the placenta and hydroxylation of PCBs by the fetus suggest the potential for greater impact on the fetus compared with the parent PCB compounds, but little is known about their health effects, particularly in humans.

Objectives

The objective of this study was to evaluate the associations between prenatal OH-PCB exposure and neurodevelopment in children at 16 months of age in eastern Slovakia.

Methods

A birth cohort (n = 1,134) was enrolled during 2002–2004. We analyzed six OH-PCB metabolites (4-OH-CB-107, 3-OH-CB-153, 4-OH-CB-146, 3′-OH-CB-138, 4-OH-CB-187, and 4′-OH-CB-172) in a subset of the cohort. The Bayley Scales of Infant Development were administered to the children at the 16-month follow-up visit. We developed multiple linear regression models predicting standardized scores for the Mental Development Index (MDI) and Psychomotor Development Index (PDI) from maternal (n = 147) and cord (n = 80) serum OH-PCB concentrations, adjusting for sex of child, district, HOME (Home Observation for Measurement of the Environment) score, and maternal score on Raven’s Progressive Matrices.

Results

Cord 4-OH-CB-107 was significantly associated with lower MDI (β = −2.27; p = 0.01) and PDI (β = −4.50; p = 0.004). Also, maternal 4-OH-CB-107 was significantly associated with lower MDI (β = −1.76; p = 0.03) but not PDI. No other OH-PCB metabolites were associated with decreased PDI or MDI.

Conclusions

Our findings showed a significant association of 4-OH-CB-107 with decreased MDI, which can possibly be mediated by endocrine disruption, altered neurotransmitter functions, or reduced thyroid hormone concentrations in brain.  相似文献   

16.
17.
PBDE and PCB content has been determined in 0+ bleak (Cyprinus alburnus), nase (Chondrostoma soetta), gudgeon (Cyprinus gobio), chub (Cyprinus cephalus), and barbel (Barbus sp.) as well as in bed sediments sampled from the River Po upstream and downstream of the confluence of a tributary draining a highly industrialized and urbanized subbasin. Both groups of chemicals were present at higher levels in fish and sediments downstream from the confluence. In addition, whole-body concentrations of PBDEs and PCBs were different among species despite the young specimen age. The fact that PBDEs and PCBs were higher in benthivorous versus planktivorous fish, as well as in carnivorous versus herbivorous species, suggests that feeding behavior is a major controlling factor that may help differentiate the accumulation levels of 0+ juveniles. Of the five species, the pelagic/planktivorous cyprinid bleak (C. alburnus) showed the lowest concentrations (111 ng PBDE/g lipid weight [l.w.], 2016 ng PCB/g l.w.), whereas the benthic dweller and feeder barbel (Barbus sp.) had the highest concentrations of both groups of chemicals (259 ng PBDE/g l.w., 4785 ng PCB/g l.w.). The rank order of species contamination was essentially stable upstream and downstream from the tributary, and the congener contribution of PBDEs was also similar. In general, BDE-47 was the dominant congener, followed by BDE-100, -154, -153, and -28. BDE-209 dominated the PBDE congener profiles of sediments but was not found in any fish sample. Conversely, an unidentified hexa-BDE congener, which was not detected in sediments, was found in all fish species. The levels of PBDEs and PCBs determined in adult goby (Padogobius martensii), a small demersal predator also examined in the same river stretches, provided additional useful insights with which to interpret results.  相似文献   

18.
A total of 127 and 177 seafood samples from Malaysia were analyzed for polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs), respectively. The World Health Organization-toxic-equivalency quotients (WHO-TEQ) of PCDD/Fs varied from 0.13 to 1.03 pg TEQ g?1, whereas dl-PCBs ranged from 0.33 to 1.32 pg TEQ g?1. Based on food-consumption data from the global environment monitoring system—food contamination monitoring and assessment programme, calculated dietary exposures to PCDD/Fs and dl-PCBs from seafood for the general population in Malaysia were 0.042 and 0.098 pg TEQ kg?1 body weight day?1, respectively. These estimations were quite different from the values calculated using the Malaysian food-consumption statistics (average of 0.313 and 0.676 pg TEQ kg?1 body weight day?1 for PCDD/Fs and PCBs, respectively). However, both of the dietary exposure estimations were lower than the tolerable daily intake recommended by WHO. Thus, it is suggested that seafood from Malaysia does not pose a notable risk to the health of the average consumer.  相似文献   

19.
In recent years, high concentrations of hexavalent chromium [Cr(VI)] have been found in the groundwater system of the Asopos River Basin. This work focuses on a Cr(VI) plume detected in the industrial area of Inofyta, the most important contamination hot spot of the Asopos River Basin. A groundwater flow and Cr(VI) transport model was developed to assess the behaviour of the plume and investigate the location of a suspected nearby source zone. According to the model results, the suspected source zone location is highly probable and the Cr(VI) plume does not migrate significantly. Based on the above findings, it is believed that the remediation effort could potentially be very effective in the area, if the remediation plan is designed properly. In order to assess the remediation potential of (a) natural attenuation and (b) polyphenol-coated nZVI treatment, two model scenarios were created and their results were compared and discussed.  相似文献   

20.

This paper investigates the concentrations of PCBs in the water and sediment media and its bio-concentration in the fish host-parasite bentho-pelagic food chain in Epe lagoon. Samples of water, sediment, plankton, mollusks, fish and intestinal helminth parasites were collected from three stations (Oriba, Imode and Ikosi) in Epe Lagoon. Concentration of total PCBs in the surface water and sediment across the stations ranges from 3.20 to 6.00 ppb and 405.50–860.70 ppb respectively. Imode had the highest concentrations. The plankton bio-concentrates most PCBs in Ikosi (286.70 ppb) followed by Imode concentration (165.40 ppb), then Oribo (92.60 ppb) with total bio-concentration of 544.60 ppb. Surface water temperature negatively and strongly correlates with PCBs in the plankton. The planktons bio-concentrates total PCBs 44 times than that in the surface water. Chrysichthys nigrodigitatus bio-concentrates total PCBs 48 times than that in the surface water. Bioaccumulation of PCBs in human food chain could pose health risk.

  相似文献   

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