| 1. |
- Hovander, Lotta, et al.
(författare)
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Levels of PCBs and their metabolites in the serum of residents of a highly contaminated area in eastern Slovakia
- 2006
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Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 40:12, s. 3696-3703
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Tidskriftsartikel (refereegranskat)abstract
- The over-riding aim of the present investigation was to obtain information concerning exposure that can be used as a basis for studies on the health of individuals residing in the Michalovce area of eastern Slovakia which is heavily contaminated by polychlorinated biphenyls (PCBs). Accordingly, this work focused on determination of serum concentrations of hydroxylated (OH-PCBs) and methylsulfonyl-substituted (MeSO2-PCBs) metabolites of PCBs. One hundred and twenty-two men and women, 20-59 years of age, living in the contaminated area and 175 from the control Stropkov/Svidnik district were selected randomly from 2047 sampled individuals. Following a specially designed cleanup, the levels of various congeners of OH-PCBs and MeSO2-PCBs in their serum were quantitated by gas chromatography and mass spectrometry, with comparison to authentic reference standards. The median concentrations of PCB congeners and their OH-PCB and MeSO2-PCB metabolites were 2-3-fold higher in residents of Michalovce than in the control region. The levels of certain OH-PCB metabolites were in the same high range as those of individual PCB congeners, whereas the MeSO2-PCB levels were significantly lower. The PCB and their metabolites were present at slightly higher concentrations in men than in women, and the serum levels of PCBs and MeSO2-PCBs increased with increasing age. Thus, the environmental contamination resulting from previous industrial production of PCBs has led to elevated concentrations of PCBs and their metabolites in the serum of individuals living in the Michalovce area.
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| 2. |
- Langer, Pavel, et al.
(författare)
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Possible effects of persistent organochlorinated pollutants cocktail on thyroid hormone levels and pituitary-thyroid interrelations.
- 2007
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Ingår i: Chemosphere. - 0045-6535. ; 70:1, s. 110-118
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Tidskriftsartikel (refereegranskat)abstract
- In polluted district of Michalovce in East Slovakia (POLL) and two districts with background pollution (BCGR) 2046 adults (834 males and 1212 females aged 20-75 years) were examined. Serum levels of thyrotropin (TSH), free thyroxine (FT4), total triiodothyronine (TT3) and antithyroperoxidase antibodies (TPOab) were estimated by electrochemiluminiscent assay and also these of 15 polychlorinated biphenyl congeners (PCBs), p,p'-DDE, p,p'-DDT, hexachlorobenzene (HCB) and hexachlorocyclohexane were measured by high resolution gas chromatography/mass spectrometry. In addition, also dioxins, furans, coplanar- and mono-ortho-PCBs as well as selected hydroxylated and methylsulphonated PCBs and DDE metabolites were measured by appropriate methods based on gas chromatography/mass spectrometry principle. In POLL significantly higher levels of all organochlorines were found than these in BCGR. When pooled values from both areas were stratified in terms of PCBs level and treated as continuous variables, positive association of PCBs with FT4 and TT3 was found, the latter two being also mutually associated. However, within the category of PCBs level <530ng/glipid (n=232) the association between PCBs and both the FT4 (p<0.09) and TT3 (p<0.03) was negative and any association of these was not found within the category of PCBs level of 531-1000ng/g (n=691). In contrast, in the category of 531-2000ng/g (n=1307) positive association appeared between PCBs and FT4 (p<0.001) as well as TT3 (p<0.05). Highly significant association of PCBs with FT4 (p<0.001) was further found in the categories with PCBs level of 1001-101414ng/g (n=1307) and 2001-101414 (n=1123), while significant association with TT3 was observed only in the category of 531-2000ng/g. Such findings suggest possible threshold level in positive effect of PCBs on FT4 and TT3 level which seems to be individual and located somewhere around the PCBs level of 1000ng/g. However, highly significant negative association of both FT4 and TT3 with TSH was found in each of above indicated PCBs categories. Considerable difference in FT4 and TT3 level between large groups of subjects with the same range of PCBs level was also found suggesting different individual susceptibility to the effects of organochlorines. Among a total of 26 cases from POLL with very low TSH level (<0.5mUl(-1)) 13 cases showed very high level of PCBs, FT4 and TT3, thus supporting a hypothesis on a novel sporadic form of high PCBs related peripheral subclinical hyperthyroidism possibly resulting from the long-term disruption of equilibrium between bound and free thyroxine in plasma by high PCBs level followed by a striking inhibition of TSH release from the pituitary.
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| 3. |
- Langer, Pavel, et al.
(författare)
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Thyroid ultrasound volume, structure and function after long-term high exposure of large population to polychlorinated biphenyls, pesticides and dioxin.
- 2007
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Ingår i: Chemosphere. - 0045-6535. ; 69:1, s. 118-27
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Tidskriftsartikel (refereegranskat)abstract
- We examined 2,046 adults (834 males and 1,212 females aged 20-75 years) from polluted district in East Slovakia (POLL) and two neighboring upstream and upwind located districts of background pollution (BCGR). By ultrasound we estimated the thyroid volume (ThV), hypoechogenicity (HYE), nodules and cysts. Serum levels of thyrotropin (TSH), thyroperoxidase antibodies (TPOab) and thyroglobulin were estimated by electrochemiluminiscent assay and these of 15 PCB congeners, p,p'-DDE, p,p'-DDT, hexachlorobenzene (HCB) and hexachlorocyclohexane by high-resolution gas chromatography. In 320 subjects also selected hydroxylated and methylsulfonated PCB metabolites, polychlorinated dibenzo-dioxins (PCDDs), -furans (PCDFs), five dioxin-like coplanar and eight mono-ortho PCB congeners were estimated. Urinary iodine was measured by automatic microplate method. Reciprocal positive association was found between three major POPs (PCBs, DDE and HCB), the levels of these and also PCDDs plus PCDFs in polluted area being considerably higher than in background pollution area. ThV in groups of males and females from POLL with high PCBs level was significantly higher (p<0.001 by t-test) then in age and sex matched groups from BCGR with low PCBs level. In 1,048 males and females aged <60 years with serum PCBs level >1,000 ng g(-1) lipid (median=1,756 ng g(-1)) a significant effect of age on ThV was found (p<0.01 by ANOVA), while in 921 respective subjects with PCBs level <1,000 ng g(-1) (median=661 ng g(-1)) it was not. These findings supported the view on the additional effect of PCBs on ThV other than that of age. Since the urinary iodine in both districts showed optimal range, any interfering effect of unsatisfactory iodine intake on ThV may be excluded. The frequency of autoimmune thyroiditis signs such as HYE, increased serum level of TPOab and TSH resulting in subclinical or overt thyroid hypofunction was positively associated with sex, age and organochlorine levels. The increase of such frequency in males with POPs levels was much more abrupt than that in females. No considerable differences in the frequency of thyroid nodules as related to PCBs level were found.
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| 4. |
- Linderholm, Linda, et al.
(författare)
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Maternal and cord serum exposure to PCB and DDE methyl sulfone metabolites in eastern Slovakia
- 2007
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 69:3, s. 403-410
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Tidskriftsartikel (refereegranskat)abstract
- Polychlorinated biphenyls (PCBs) were commercially produced between 1959 and 1984 in eastern Slovakia. Improper handling led to a highly contaminated local environment and high levels of PCBs in humans and wildlife in the Michalovce area. The aim of this study was to analyse serum for methylsulfonyl metabolites of PCB (MeSO2-PCBs) and DDE (3-MeSO2-DDE) in serum samples from pregnant women and in a selected number of paired cord blood samples to assess maternal sulfone levels and patterns, and transplacental transfer of these metabolites. The donating women were from two districts in eastern Slovakia. A liquid–liquid extraction method together with separation of substance groups and further clean-up on silica gel columns were applied prior to analysis by gas chromatography/mass spectrometry. 3-MeSO2-DDE was the major methyl sulfone in most of the samples followed by a yet not identified MeSO2-hexaCB, 4′-MeSO2-CB101, 4′-MeSO2-CB87 and 4-MeSO2-CB149. The women from the contaminated area had three times higher concentrations of the MeSO2-PCBs than women from the reference area. This is the first report on methyl sulfone metabolites of PCB and DDE in human cord serum. It is shown that these metabolites are transported through the placenta. The levels of MeSO2-PCBs in the maternal serum were about 1.5 times higher than in the corresponding cord serum on a lipid weight basis. For 3-MeSO2-DDE, the levels were about the same in maternal and cord serum. The difference in the maternal:cord ratio, comparing MeSO2-PCBs with 3-MeSO2-DDE might be due to differences in transport through the placenta caused by their different affinities for lipoproteins and plasma proteins.
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