Polychlorinated biphenyl contamination of nursing mothers' milk in Michigan.

The problem of environmental contamination by toxic substances and human exposure to these substances has attracted increased attention in recent years. Particular concern has centered on polychlorinated biphenyls (PCBs), which have become widespread environmental pollutants as well as contaminants of the human population. This paper reports data from a study of PCB contamination of nursing mothers' breast milk in Michigan. During 1977 and 1978, breast milk samples of 1,057 nursing mothers residing in Michigan were tested for PCB residues. All of the 1,057 samples collected from 68 of the state's 83 counties contained PCB residues ranging from trace amounts to 5,100 parts per million (fat weight basis). The mean level was 1,496 parts per million (ppm), with 49.5 per cent of the samples having PCB levels of 1-2 ppm, 17.4 per cent had 2-3 ppm, and 6.14 per cent had more than 3 ppm. There was no consistent trend in the level of PCB contamination over the 24 months of monitoring. The mean PCB level for the eighth quarter of monitoring was slightly higher than for the first quarter. The public health significance of PCB contamination in human populations and its effects on breast-fed for eight months by a woman with the average PCB level in this sample would have an estimated body burden of approximately 0.89 ppm of PCBs. The implications of PCB contamination of human milk with regard to current breast-feeding practices are discussed and several precautionary measures are recommended.     

Polychlorinated biphenyl and organochlorine pesticide contamination signatures in deep-sea fish from the Mediterranean Sea

Polychlorinated biphenyl (PCB) and OCP concentrations were determined in the livers of two deep-sea fish species, roughsnout grenadier and hollowsnout grenadier, from the Adriatic Sea. In both species, contaminant concentrations were in the following order: PCBs>DDTs>>HCB. Contaminant load was higher in roughsnout grenadier (PCB: 12,327 ng g⁻¹; DDTs: 5357 ng g⁻¹; HCB: 13.1 ng g⁻¹) than in hollowsnout grenadier (PCB: 1234 ng g⁻¹; DDTs: 763 ng g⁻¹; HCB 6.3 ng g⁻¹). PCB patterns were dominated by higher chlorinated congeners (hexa-CBs: 50.3-52.1%, hepta-CBs: 29.6-35.5%, penta-CBs: 8.0-11.1% and octa-CBs :5.2-5.4%). PCBs 138, 153 180 and 187 were the most abundant. Regarding the DDT pattern, p,p′-DDE was prevalent in both species (roughsnout grenadier: 99.7%, hollowsnout grenadier: 90%), suggesting no recent DDT input. In both species, the total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent (TEQ) concentrations (roughsnout grenadier: mean 43.77 pg/g, hollowsnout grenadier: mean 20.49 pg/g), calculated from non- and mono-ortho PCBs, reached those encountered in marine organisms at higher levels in the trophic chain.     

Polychlorinated biphenyl contamination of the spider crab (Maja brachydactyla): influence of physiological and ecological processes

Maja brachydactyla is a decapod crustacean widely distributed along the Northeast Atlantic coasts. The main objective of this work was to establish the influence of ontogenic factors, such as growth, aging, seasonal migrations, and reproduction, on the contamination of this species by polychlorinated biphenyls (PCBs). Two populations were studied: One in the Seine Bay (Eastern English Channel), which is exposed to greatly contaminated discharges from the Seine River, and one in the Iroise Sea (Western Brittany), which is little contaminated by such man-made compounds. At both sampling areas, PCB analysis revealed concentrations in hepatopancreas that were 10- and 50-fold higher than concentrations in gonads and muscle, respectively. Levels of 2,2',4,4',5,5'-hexachlorobiphenyl (CB153) increased with the age of the spider crabs, whereas their seasonal migrations had no direct effect. No significant sex effect was observed with regards to CB153 levels, but adult females exhibited PCB fingerprints different from those of males, probably because of the influence of the reproductive cycle on enzymatic system activity. Finally, spawning gave rise to a higher CB153 decontamination of female body burdens for specimens from the Iroise Sea than for those from the Seine Bay.     

Evaluation of polychlorinated biphenyl remediation at a superfund site using tree swallows (Tachycineta bicolor) as indicators

We studied tree swallows (Tachycineta bicolor) at the Sangamo National Priorities List (NPL) site and a reference area (Little Grassy) within Crab Orchard National Wildlife Refuge, Illinois, USA, to evaluate the bioavailability of polychlorinated biphenyls (PCBs) at the NPL site following remediation. Tree swallow eggs and 12- to 17-d-old chicks were collected from April to June 2004 and 2005. Total egg PCB concentrations in eggs did not differ between years at Sangamo; mean concentrations at Sangamo in 2004 to 2005 (4,452 ng/g) were higher than those from Little Grassy in 2004 (351 ng/g; p = 0.002) and 2005 (705 ng/g; p = 0.007). A positive PCB dilution in chicks is equivalent to relatively large amounts of exposure and absorption. Total PCB daily dilution in chicks in 2004 and 2005 averaged 92.4 and -203 ng/g/d at Sangamo and -21.8 and -42.7 ng/g/d at Little Grassy. Dioxin toxic equivalents (TEQs) in eggs in 2004 and 2005 were 1,844 and 676 pg/g at Sangamo and 165 and 128 pg/g at Little Grassy. Mean TEQs in chicks in 2004 and 2005 were 117 and 23.8 pg/g body weight at Sangamo and 0.8 and 0.7 pg/g body weight at Little Grassy. Total PCB concentrations in eggs and chicks at Sangamo and Little Grassy appeared to be comparable to other PCB-contaminated and reference sites. Our data demonstrate that tree swallows using the Sangamo site continue to accumulate significant quantities of PCBs seven years after remedial actions. These findings prompted a reevaluation of remediation at the site and underscore the importance of postremediation monitoring of ecological receptors, particularly in cases involving persistent environmental contaminants.     

食品中多氯联苯的污染及其控制

有机化合物多氯联苯（PCBs）自1881年由德国人成功合成后，美国于1929年开始工业生产。它是一类具有两个相联苯环结构的含氯化合物，它具有非常优良的物理特性，因而被广泛应用于许多行业之中。多氯联苯在使用过程中，通过各种途径进入环境中，并通过食物链传递和富集而进入人体，因此对人类健康危害极大，目前各国已普遍减少使用或停止生产多氯联苯。但是，多氯联苯已使用近40年的时间，由于它用途极其广泛，理化性质稳定，又对人体健康危害较大，因此各国都把多氯联苯列入必须优先处理的食品污染物名单中。     

Polychlorinated biphenyl congeners in blood of Wisconsin sport fish consumers

As part of a study to evaluate the effect of chemical contaminants on Wisconsin sport fish consumers, measurements were made of polychlorinated biphenyl (PCB) congeners in human blood sera. A high resolution gas chromatography procedure was employed, with 13 individual congeners used as standards. Analytical recoveries and precision were >90% and replicates were always within ±30%. Total concentrations, obtained by summing quantified congeners, ranged from 0.6 to 27.1 g/L. Conventional packed column PCB analysis, conducted on a subset of samples, gave higher total PCB results. On a congener specific basis, congeners 153 (245-245), 138 (234-245), 180 (2345-245) and 118 (245-34) were found most often. These congeners have been reported to be prominent in other matrices. Of the congeners found, 118, 138, and possibly 180 are potentially the most toxic (based on current toxicological information).     

Pediatric aspects of the Michigan polybrominated biphenyl contamination

In 1973, Michigan cattle feed was accidentally contaminated with polybrominated biphenyls (PBB) and subsequently PBB has been found in the serum, body fat, and breast milk of most Michigan residents. Because of numerous complaints of ill health, a survey of Michigan farm children, the most heavily exposed group, was undertaken in 1976 to determine the nature and scope of the problem. Examination of the data from 292 Michigan children showed that the prevalence of symptoms was related to the quarantine status of the farm and to the method of invitation into the study. Serum PBB levels were related to the quarantine status of the farm but not to the method of invitation into the study. No significant effects of age or sex were found on the prevalence of symptoms or serum PBB levels, except that the teenage (13–16) males had somewhat higher PBB levels. Despite the frequent reporting of symptoms of ill health, physical examination failed to reveal any objective alterations that could be attributed to PBB. The most striking finding has been a statistically significant negative correlation between the prevalence of symptoms and the serum-PBB levels. So far, the reason for this negative correlation is unexplained.     

Polychlorinated biphenyl congener patterns in tissues from a selection of British birds

A large selection of polychlorinated biphenyl (PCB) congeners was determined in tissues from several British bird species including three sea birds, four birds of prey, and herons (Ardea cinerea). The congener “signatures” were consistent between different tissues of the same individual, but varied within and between species. Congeners 138, 153, and 180 were dominant in most samples. Nevertheless, ∑PCB values were wide ranging (0.02–105 μg/g wet weight) and also differed considerably in subsamples of different tissues from individual birds. Applying recently reported toxicity equivalency factors (TEFs) for non-ortho, mono-ortho, and di-ortho substituted PCBs to liver concentrations of such congeners, it appears that the mono-ortho congeners 105 and 118 make a high contribution to TEFs when their toxicities are weighted by concentration. The study highlights that caution is needed when interpreting data on contaminants in wildlife, but suggests that careful sampling will reduce the many variables which can give rise to differing congener patterns and ∑PCB values.     

Polychlorinated biphenyl exposure and neuropsychological status among older residents of upper Hudson River communities

BACKGROUND: Polychlorinated biphenyls (PCBs) may accelerate the cognitive and motor dysfunction found in normal aging, but few studies have examined these outcomes and PCB exposure among older adults. OBJECTIVE: We evaluated neuropsychological status and low-level PCB exposure among older adults living along contaminated portions of the upper Hudson River in New York. METHODS: A total of 253 persons between 55 and 74 years of age were recruited and interviewed, and provided blood samples for congener-specific PCB analysis. Participants also underwent a neuropsychological battery consisting of 34 tests capable of detecting subtle deficits in cognition, motor function, affective state, and olfactory function. RESULTS: After adjustment for potential confounders, the results indicated that an increase in serum total PCB concentration from 250 to 500 ppb (lipid basis) was associated with a 6.2% decrease in verbal learning, as measured by California Verbal Learning Test trial 1 score (p = 0.035), and with a 19.2% increase in depressive symptoms, as measured by the Beck Depression Inventory (p = 0.007). CONCLUSIONS: The results suggest that exposure to PCBs may be associated with some measures of memory and learning and depression among adults 55-74 years of age whose current body burdens are similar to those of the general population. Although the results are useful in delineating the neuropsychological effects of low-level exposure to PCBs, further studies of whether older men and women are a sensitive subpopulation are needed.