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Background and Aim: Persistent organochlorine pollutants (POPs) have in epidemiological studies been associated with health hazards. The exposure window might be crucial and it is, accordingly, important to analyze exposure concentrations in samples collected at the window of interest. This makes the use of stored blood samples extremely interesting. However, small blood volumes from stored samples in biobanks means that the researchers in epidemiological studies most often have to select a limited number of biomarkers representing the POP exposure and abstain from analyses of lipid concentrations. This raises the question of the necessity of lipid adjustment. The aim of the present study was to evaluate the correlation between fresh weight and lipid adjusted concentrations., Methods: We included data from studies were we have used the PCB congener 2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153) as a biomarker for POP exposure and where fresh weight as well as lipid adjusted PCB-153 concentrations are known (n=1628). The variety of the cohort members in the different studies gave us the possibility to better understand how well these measures correlate., Results: When all individuals were included in the analyses a correlation coefficient of 0.95 between fresh weight and lipid adjusted serum concentrations was obtained. Restricting the analyses to specific subgroups (based on gender, fasting status, age and BMI) gave correlation coefficients between 0.85 and 0.97., Conclusions: This study does strongly support the use of samples from biobanks in epidemiological studies for analyzing PCBs, at least regarding PCB-153, even though it is not possible to lipid adjust the results., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Recently, the effect of exposure to persistent organic pollutants (POPs) on sperm concentration was only seen in men with a short androgen receptor (AR) gene CAG repeat. In order to investigate whether these effects could be observed also in vitro, we tested the impact of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-bis-(4-chlorophenyl)-2,2-dichloroethene (4,4'-DDE) on 5α-dihydrotestosterone activated ARs containing 16, 22 and 28 CAG repeats, respectively. Single exposure to 4,4'-DDE had the most pronounced effect on the AR activity containing 16 CAG repeats, whereas 28 CAG was the most sensitive variant when a mixture of the two compounds was added. Thus, our in vitro results have confirmed the in vivo data indicating a CAG repeat length dependent effect of endocrine disrupters on the AR activity., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Arctic is contaminated with persistent organochlorine pollutants (POPs), and exposure to these compounds may differ between south and north in Norway. POPs may have negative impact on male reproductive characteristics. We compared serum levels of the CB-153 and p,p'-DDE in men who were born and had lived most of their lifetime south and north (close to or above the Arctic Circle) in Norway. We found no geographical differences in levels of CB-153 (south: 50 ng/g lipid (mean), north: 59 ng/g lipid; p=0.27) or sperm parameters. However, the levels of p,p'-DDE were higher in south than in north (81 ng/g lipid (mean) vs. 66 ng/g lipid; p=0.02), as were the levels of total and free testosterone. The FSH levels were lowest in south. A strong relationship between the CB-153 and the SHBG levels was observed. The regional differences observed for p,p'-DDE, testosterone and FSH were not reflected in the semen quality., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: The incidence of type 1 diabetes in Europe is increasing at a rate of about 3% per year and there is also an increasing incidence throughout the world. Type 1 diabetes is a complex disease caused by multiple genetic and environmental factors. Persistent organochlorine pollutants (POPs) have been suggested as a triggering factor for developing childhood type 1 diabetes. The aim of this case-control study was to assess possible impacts of in utero exposure to POPs on type 1 diabetes., Methodology/ Principal Findings: The study was performed as a case-control study within a biobank in Malmö, a city located in the Southern part of Sweden. The study included 150 cases (children who had their diagnosis mostly before 18 years of age) and 150 controls, matched for gender and day of birth. 2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153) and the major DDT metabolite 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE) were used as a biomarkers for POP exposure. When comparing the quartile with the highest maternal serum concentrations of PCB-153 with the other quartiles, an odds ratio (OR) of 0.73 (95% confidence interval [CI] 0.42, 1.27) was obtained. Similar results was obtained for p,p'-DDE (OR 0.56, 95% CI 0.29, 1.08)., Conclusions: The hypothesis that in utero exposure to POPs will trigger the risk for developing type 1 diabetes was not supported by the results. The risk estimates did, although not statistically significant, go in the opposite direction. However, it is not reasonable to believe that exposure to POPs should protect against type 1 diabetes.

A simple and fast method is presented to be used for example in studies on the relationship between serum levels of persistent organic pollutants and type 2 diabetes mellitus. Method is based on liquid-liquid extraction and gas chromatography coupled with high-resolution mass spectrometry. In the sample pre-treatment special attention was paid to minimize the number of sample manipulation steps and the amounts of organic solvents needed. Compounds analyzed were 2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE), the major metabolite of DDT. The method included extraction and cleanup of 0.2ml of serum in a single test tube and subsequent analysis of the extract from 0.2ml final volume. Validation was conducted to explore the performance of the method. The limits of detection for p,p'-DDE and PCB-153 based on the standard deviation of the blank samples were 4.3 and 3.1pg/ml, respectively. Repeatability was less than 2.5% at three concentration levels tested and recovery from Certified Reference Material SRM 1589a was 84% for p,p'-DDE and 87% for PCB-153 of the certified values, respectively. Serum samples from the AMAP intercalibration round 2008-2 were also analyzed, and results were 101-116% of the assigned values. The presented method was used for an epidemiological study with more than 700 serum samples from a type 2 diabetes cohort from Sweden.

Persistent organochlorine pollutants (POPs), such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), dichloro diphenyl trichloroethane (DDT) and its major metabolite 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p' -DDE) have been associated with type 2 diabetes mellitus (T2DM) in recent epidemiological studies. We have analysed 2,2',4,4',5,5' -hexachlorobiphenyl (CB-153) and p,p'-DDE in 544 serum-samples from Swedish women with a median age of 50 years. The participants were asked if they had diabetes and if so, what type of diabetes, years since diagnosis and what kind of treatment they had. Associations between exposure and T2DM were analysed by logistic regression. Moreover, trends of T2DM prevalence were tested with Jonckheere-Terpstrá test. Sixteen of the 544 women (3%) had diabetes, of which 15 were classified as T2DM. There was a significant association with T2DM for both CB-153 (an increase of 100 ng/g lipid corresponded to an odds ratio [OR] of 1. 6, 95% confidence interval [CI] 1. 0, 2. 7) and p,p9-DDE (OR 1. 3, 95%CI 1. 1, 1. 6). In addition, significant positive trends between quartiles of CB-153 and T2DM (P 5 0. 004) and p,p9-DDE and T2DM (P 5 0. 002) were observed. The study shows an association between POP serum concentrations and an increased prevalence of T2DM.

Persistent organochlorine pollutants (POPs) are suspected to interfere with hormone activity and the normal homeostasis of spermatogenesis. We investigated the relationships between sperm DNA fragmentation, apoptotic markers identified on ejaculated spermatozoa and POP levels in the blood of 652 adult males (200 Inuits from Greenland, 166 Swedish, 134 Polish and 152 Ukrainian). Serum levels of 2, 2', 4, 4', 5, 5'-hexachlorobiphenyl (CB-153), as a proxy of the total POP burden, and of 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE), as a proxy of the total DDT exposure were determined. Sperm DNA fragmentation was measured by using the TUNEL assay, whereas immunofluorescence methods were utilized for detecting pro-apoptotic (Fas) and anti-apoptotic (Bcl-xL) markers. Both TUNEL assay and apoptotic markers were statistically differed across the four populations. No correlation between neither sperm DNA fragmentation nor apoptotic sperm parameters and the large variations in POPs exposure was observed for the separate study groups. However, considering the European populations taken together, we showed that both %TUNEL positivity and Bcl-xL were related to CB-153 serum levels, whereas our study failed to demonstrate any relations between DDE and %TUNEL positivity and apoptotic sperm biomarkers (Fas and Bcl-xL) in any region or overall regions. These results suggest that CB-153 and related chemicals might alter sperm DNA integrity and Bcl-xL levels in European adult males, but not in the highly exposed Inuit men. Additional issues (genetic background, lifestyle habits and characterization of total xeno-hormonal activities) need to be investigated in order to fully assess the population variations observed.

Background: Animal and epidemiologic data indicate that exposure to persistent organochlorine pollutants (POPs) may disrupt the hypothalamus-pituitary-thyroid (HPT) and the hypothalamus-pituitary-gonadal (HPG) axes. We have assessed whether the POP-biomarkers 2,2'4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethene (p,p'-DDE) affect thyrotropin (TSH), thyroid hormones, gonadotropins or sex hormone concentrations in men., Methods: Lipid adjusted serum concentrations of CB-153, and p,p'-DDE, were determined in 196 men (median age 59 years, range 48-82). Hormone analyses in serum were performed with immunoassays. The effect of CB-153 and p,p'-DDE (as continuous or categorized variables) were evaluated by linear regression models, adjusting for potential confounders., Results: There was a significant positive association between p,p'-DDE and TSH. An increase of 100 ng/g lipid of p,p'-DDE corresponded to an increase of 0.03 mU/l (95% Confidence Interval (CI) 0.01, 0.05) in TSH level. The explanatory value (R(2)) of the multivariate model was only 7%. Moreover, there was a significant negative association between p,p'-DDE and estradiol. An increase of 100 ng/g lipid of p,p'-DDE corresponded to a decrease of 0.57 pmol/l (95% CI -1.0, -0.12) in estradiol level. The R(2)-value was only 4%. No associations were observed between any of the POP biomarkers and the other hormones., Conclusions: The positive association between p,p'-DDE and TSH and the negative association between p,p'-DDE and estradiol, among middle-aged and elderly men, were not accompanied by associations between the POP-markers and thyroxin, testosterone, and gonadotropins, respectively. The results gives some additional support for that POP exposure may affect HPT- and HPG-axes also in humans, but the overall epidemiological data are still not coherent enough to allow any firm conclusions.

Background: An important question is whether human serum levels of persistent organic pollutants has continued to decrease during the last decades. The aim of this study was to assess intra-individual variations over time of serum levels of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethene (p,p'-DDE) and hexachlorobenzene (HCB), considering the impact of a number of possible determinants., Methods: Blood samples were drawn for the same 39 subjects in 1991 and 2001. Interviews were made at both occasions. Lipid adjusted serum concentrations of CB-153, p,p'-DDE and HCB were determined in both sets of blood samples using gas chromatography-mass spectrometry. The fatty acid composition of the serum lipids was analyzed by means of gas-liquid chromatography., Result: The CB-153 concentrations in serum had averagely decreased with 34% in between 1991 and 2001 (p<0.001). Of individual determinants only increasing BMI was associated with decreasing CB-153 levels (beta=-1.0, 95% CI -1.8, -0.2, p=0.01), explaining 13% of the variation. The average decrease of p,p'-DDE was 55%, and could only weakly be associated with a relative increase of BMI (beta=-1.0, 95% CI -2.3, 0.2, p=0.09), explaining only 5% of the variation. The average decrease of HCB was 53%, and was associated only with high fish consumption in 1991, explaining 12% of the variation., Conclusions: The results support a continuing decrease in human body burdens of PCBs, DDE and HCB during the 1990s. The explanatory factors relative change of BMI and fish consumption explained only a minor part of the time-related variations in serum levels.

Objective: Recent studies indicate that persistent organohalogen pollutants (POPs) may contribute to sex ratio changes in offspring of exposed populations. Our aim in the present study was to investigate whether exposure to 2,2 ,4,4 ,5,5 -hexachlorobiphenyl (PCB-153) and dichlorodiphenyldichloroethene (p,p -DDE) affects sperm Y:X chromosome distribution., Subjects and Methods: We obtained semen and blood for analysis of PCB-153 and p,p -DDE levels from 547 men from Sweden, Greenland, Poland (Warsaw), and Ukraine (Kharkiv), with regionally different levels of POP exposure. The proportion of Y- and X-chromosome-bearing sperm in the semen samples was determined by two-color fluorescence in situ hybridization analysis., Results: Swedish and Greenlandic men had on average significantly higher proportions of Y sperm (in both cohorts, 51.2%) and correspondingly higher lipid-adjusted concentrations of PCB-153 (260 ng/g and 350 ng/g, respectively) compared with men from Warsaw (50.3% and 22 ng/g) and Kharkiv (50.7% and 54 ng/g). In the Swedish cohort, log-transformed PCB-153 and log-transformed p,p -DDE variables were significantly positively associated with Y-chromosome fractions (p-values 0.04 and <0.001, respectively). On the contrary, in the Polish cohort PCB-153 correlated negatively with the proportion of Y-bearing fraction of spermatozoa (p=0.008)., Conclusions: The present study indicates that POP exposure might be involved in changing the proportion of ejaculated Y-bearing spermatozoa in human populations. Intercountry differences, with different exposure situations and doses, may contribute to varying Y:X chromosome ratios.

Persistent organochlorine pollutants (POPs) such as polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (p,p'-DDE), the major metabolite of dichlorodiphenyltrichloroethane (DDT), are stable lipophilic compounds widely found in the environment and in the general population. They can enter the food chain, and their negative impact on male reproduction is currently under active scrutiny. To explore the hypothesis that environmental exposure to these compounds is associated with altered sperm chromatin structure integrity in human sperm, we conducted a study of 176 Swedish fishermen (with low and high consumption of fatty fish, a very important exposure source of POPs). We determined serum levels of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and p,p'-DDE, and we used the sperm chromatin structure assay (SCSA) to assess sperm DNA/chromatin integrity. When CB-153 serum levels (individual dose range, 39-1,460 ng/g lipid) were categorized into equally sized quintiles, we found an association with the DNA fragmentation index (%DFI). A significantly lower %DFI was found in the lowest CB-153 quintile (< 113 ng/g lipid) compared with the other quintiles; there was a similar tendency, although not statistically significant, between %DFI and p,p'-DDE. These results suggest that POP exposure may have a slight negative impact on human sperm chromatin integrity.

Polychlorinated biphenyls (PCBs) may affect the female reproductive system in both animals and humans. In Sweden, a main exposure source to PCBs is consumption of fatty fish from the Baltic Sea. From 165 female consumers of such fish (fishermen's sisters), information on time to pregnancy (TTP) and miscarriages was collected, blood was drawn, and serum was analyzed for 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), a biomarker for total PCB exposure. TTP and miscarriage data, as well as plasma CB-153 concentrations, for 121 fishermen's wives were available from previous studies. Thus, information on 286 women was available for investigation of whether a high exposure to PCB affects fertility negatively by increasing the TTP. The concentrations of CB-153 at the time of conception were estimated and trichotomized into low, medium, and high exposure groups. When we analyzed the joint data set of fishermen's wives and fishermen's sisters, a decrease rather than an increase in TTP was indicated for women in the medium (fecundability ratio 1.27 [95% confidence interval 0.89-1.82]) and high (fecundability ratio 1.42 [0.99-2.03]) exposure groups compared to those in the low exposure group. Similar results were found when we stratified on the original data set (fishermen's wives and fishermen's sisters) or childhood exposure. Women with miscarriages had lower estimated past CB-153 concentrations than women with live births. Our data provide no evidence of a hazardous effect associated with CB-153 concentration in the exposure range assessed. The exposure levels found in the fishermen's families, although high compared to that in the general Swedish population, may not be high enough to negatively affect fertility.

Background: During the last decades, there has been concern that exposure to endocrine disruptors, such as persistent organochlorine pollutants (POPs), may contribute to an impairment of male reproductive function. To investigate whether exposure to 2,2'4,4'5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE) affects semen quantity and quality and reproductive hormones, 195 Swedish fishermen, aged 24-65 years, were investigated., Methods: The men provided semen samples which were analysed in a mobile laboratory unit. Blood samples and information relating to lifestyle, medical and reproductive history were obtained., Results: The subjects had a median CB-153 serum level of 193 ng/g lipid (range 39-1460) and a median p,p'-DDE serum level of 240 ng/g lipid (range 334-2251). When CB-153 was categorized into quintiles, the subjects in the quintile with the highest concentration (> 328 ng/g lipid), tended to have decreased sperm motility compared with the subjects in the lowest quintile (< 113 ng/g lipid). The age-adjusted mean difference was 9.9% (95% confidence interval -1.0 to 21% P = 0.08). We found no significant associations between p,p'-DDE and semen characteristics or reproductive hormones., Conclusion: The association between CB-153 and sperm motility, although not formally significant, is of interest considering the possible endocrine-disrupting effects of polychlorinated biphenyls (PCBs).

Objectives: Animal studies have shown that persistent organochlorine compounds (POC) impair normal bone metabolism and result in increased bone fragility. These findings may have health implications for POC-exposed human populations. The aim of the present study was to assess the impact of POC-contaminated fish on the self-reported fracture incidence of Swedish fishermen and their wives., Methods: A postal questionnaire was sent to 2096 fishermen and 1602 fishermen's wives from the Swedish east (exposed) coast and 4584 fishermen and 4217 fishermen's wives from the west (unexposed) coast. Self-reported fractures, together with specified current fish consumption and information about potential confounders, were registered. The response rates varied between 50% and 59%. The age distributions of the nonrespondents and respondents were almost identical. Hip, vertebral, and wrist fractures were classified as osteoporotic. The fracture incidence rates for specific skeletal locations were based on allocated fractures and person-years under risk from the age of 25 years until the time of fracture or the end of follow-up., Results: No differences in fracture incidence were observed between the east and west-coast cohorts. East-coast wives with more than one meal of fatty fish from the Baltic Sea per month had, however, an increased fracture incidence as compared with that of the east-coast wives who ate, at most, one such meal per month (age-adjusted incidence rate ratio 1.68, 95% confidence interval 1.00-2.84). No such exposure-response association was found for the fishermen., Conclusions: The present study only minimally supports an association between POC exposure through contaminated fish and an increased risk of osteoporotic fractures.

A time-related deterioration in male reproductive function caused by exposure to endocrine disrupters, including persistent organochlorines (POCs), has been hypothesized. In animal studies, POCs were found to have adverse effects on male reproductive function. However, little is known about the impact of POC exposure on reproductive parameters in men. In a study of 305 young Swedish men 18-21 years old from the general population, we correlated lipid-adjusted serum levels of 2,2',4,4',5,5' -hexachlorobiphenyl (CB-153)--an index substance for POC exposure--to markers of male reproductive function: testis size assessed by ultrasound, sperm concentration, total sperm count, sperm motility assessed manually and with a computer-aided sperm analyzer (CASA), and serum levels of follicle-stimulating hormone, inhibin B, testosterone, sexual hormone-binding globulin (SHBG), luteinizing hormone, and estradiol. We found weak but statistically significant, negative correlations between CB-153 levels and both the testosterone:SHBG ratio (r = -0.25, p < 0.001)--a measure of the biologically active free testosterone fraction--and CASA sperm motility (r = -0.13, p = 0.02). No statistically significant association with other seminal, hormonal, or clinical markers of male reproductive function was found. In previous studies of more highly POC-exposed groups of adult men, the correlation between POC exposure, including CB-153, and free testosterone levels was not statistically significant. The present study gives some tentative support for weak negative effects of CB-153 exposure on sperm motility and free testosterone levels in young men, but further semen studies on more highly exposed groups may give more firm conclusions on the hazard for male reproductive function from dietary POC exposure.

Objectives: The purpose of the study was to assess the effect of exposure to presistent organochlorine compounds through the consumption of fatty fish from the Baltic Sea on human fertility., Methods: Information on time to pregnancy, miscarriages, and subfertility was collected retrospectively by self-administered questionnaires in two cohorts of fishermen's sisters from the Swedish east coast, by the Baltic Sea, and the west coast, where fish are less contaminated. Along with cohort affiliation, fish consumption and growing up in a fishing village or fisherman's family were used as measures of exposure within the eastcoast cohort (ie, the exposed cohort)., Results: There was no support for a negative effect of the consumption of fatty Baltic Sea fish on time to pregnancy, miscarriages, or subfertility. On the contrary, some evidence pointed towards a protective effect of fatty fish consumption within both cohorts., Conclusions: No evidence of reduced fertility was found for women who could be assumed to have a high lifetime consumption of fatty fish contaminated by persistent organochlorine compounds. A possible explanation for this finding is that a positive effect of some of the constituents in fatty fish could be strong enough to disguise the hazardous effects of exposure to persistent organochlorine compounds.

The purpose of this study was to assess the association between 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) in plasma, a biomarker of exposure to polychlorinated biphenyls (PCB), and time to pregnancy (TTP) in a group of women with a varying dietary exposure to PCB. For 121 Swedish east coast fishermen's wives (median year of birth 1956, range 1945-1968), information on selt-reported TTP for the first planned pregnancy (median 2 mo, range 0-48) and CB-153 concentrations from blood samples drawn in 1995 (median 144 ng/g lipid, range 16-566) were available. Each woman's CB-153 concentration in plasma at the time immediately preceding her pregnancy was estimated, taking into account reduction of body burden of CB-153 due to lactation, the yearly reduction of PCB in Baltic Sea fish, as well as the biological half-life of CB-153. Based on the estimated CB-153 concentrations, subjects were categorized into tertiles as low (37-206 ng/g lipid), medium (207-330 ng/g lipid), and high (331-,1036 ng/g lipid) exposure groups. TTP in the medium- and high-exposure groups were then compared to TTP in the low-exposure group by estimating the corresponding success rate (i.e., the number of pregnancies per person month) ratios (SuRR) using discrete Cox regression, taking into account essential confounders. No obvious association between estimated CB-153 concentration and TTP was observed (medium vs. low: SuRR 0.77 [95% CI 0.47-1.28] and high vs. low: SuRR 0.95 10.74-1.23]). The present data give no support for a negative association between the plasma CB-153 concentrations observed in the present study and TTP. It should, however, be borne in mind that the study group was rather small and mainly included relatively young women, likely to have been only moderately exposed.

Objectives: There is a concern that persistent organohalogen toxicants, such as polychlorinated biphenyls (PCBs), might display endocrine-disrupting effects in exposed populations. In this study the correlations between PCBs and thyrotropin (TSH) and thyroid hormone concentrations in plasma were assessed in adult women., Methods: The study group consisted of 182 fishermen's wives from the Swedish east coast, with a median age of 42 years (range 23-62) and a median current consumption of contaminated fatty fish from the Baltic Sea of two meals per month (range 0-12). TSH, free (FT3) and total (TT3) triiodothyronine and free (FT4) and total (TT4) thyroxin in plasma were analyzed by immunofluorometric assays, and 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) in plasma was analyzed by gas chromatography with electron capture detection. Twenty other PCB and two hydroxy-PCB congeners were analyzed in subgroups of the women. Plasma lipid analyses were performed with enzymatic techniques., Results: The CB-153 concentration in plasma (range 16-776 ng/g lipid) was negatively correlated with the TT3 concentrations (range 1.0-3.0 nmol/l, rs = -0.29, P < 0.001). This association remained after age adjustment., Conclusions: The present study gives some support for the notion that dietary exposure to persistent organochlorine compounds (POCs) might weakly affect peripheral thyroid hormone concentrations in adult women.

The authors examined the hypothesized association between the body burden of polychlorinated biphenyls (PCB) in women and the risk of low birth weight for their infants. In Sweden, a main exposure route for PCBs and other persistent organochlorine compounds is through the consumption of fatty fish from the Baltic Sea (on the Swedish east coast). A previous comparison between a cohort of consumers of large quantities of fish from the Swedish east coast and a reference population, together with a following analysis based on questionnaire data from a case-control study within the east coast cohort, supported the hypothesized association. In 1995, blood samples were collected from the wives and ex-wives of fishermen from the Swedish east coast (n = 192) who had given birth during the period 1973-1991. Cases (n = 57), i.e., infants with low birth weight (1,500-2,750 g), were matched with controls (n = 135; birth weight, 3,250-4,500 g) on gender, parity, and calendar year of birth. The concentration of 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) in plasma was analyzed; it has been suggested that CB-153 is a relevant biomarker of exposure to PCBs. The concentration of CB-153 in the plasma of mothers during the year of childbirth was "estimated" using some alternative plausible kinetic models. For two alternative estimated exposure datasets, which were focused on separately, an increase in the risk of a low birth weight was observed at a CB-153 concentration of 300 and 400 ng/g lipid weight, respectively (adjusted odds ratios of 2.1 (95% confidence interval (CI) 1.0-4.7) and 2.3 (95% CI 0.9-5.9)). The present results strengthen the findings reported previously for this study population.

The mean concentration of the chlorinated biphenyl 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) in plasma from 192 fishermen's wives from the Swedish east coast was on a fresh weight basis 960 (range 80-4300) pg/g and lipid adjusted 160 (range 20-780) ng/g lipid. The concentration of CB-153 in plasma was significantly influenced by age, total lactation time and place of living during childhood and adolescence (fishing village vs. other place). The residential variable probably reflects early life consumption of fish from the Baltic Sea (at the Swedish east coast) contaminated with persistent organochlorine compounds.

Human plasma samples from 50 wives of fishermen have been analyzed with respect to PCBs. The non-ortho-substituted PCB congeners CB-126 and CB-169 were determined by mass spectrometry in negative ion chemical ionization mode, which demonstrated a limit of detection of 30 fg. The recoveries of the internal standards used for determination of ortho-substituted CBs were approximately 95%. Two methods, one gravimetric and the other based on enzymatic determinations of triglycerides, cholesterol and phospholipids, were compared for the determination of total amount of lipids in the plasma samples; the correlation coefficient was 0.82 and the slope 0.98. For practical reasons, enzymatic determinations are recommended for further use. The total, lipid-adjusted concentrations of PCBs in plasma were influenced by age, total lactation time and consumption of fatty fish from the Baltic Sea.

Objectives: The purpose of this study was to assess the hypothesized association between persistent organochlorine compounds through the consumption of fatty fish from the Baltic Sea (at the Swedish east coast) and low birthweight., Materials and Methods: During the period 1973-1991, 72 cases of low birthweight (1500-2750 g) were selected from among infants born to fishermen's wives within a cohort from the Swedish east coast. For each case two referents were selected. The mothers were interviewed about their dietary and smoking habits and place of living during childhood and adolescence., Results: A high total current intake of fish from the Baltic Sea (> or = 4 meals per month) tended to increase the risk of having an infant with low birthweight [adjusted odds ratio (OR) 1.9, 95% confidence interval (95% CI) 0.9-3.9]. The effect was more conspicuous for the boys (OR 3.4, 95% CI 1.1-11). No such effects were observed when the estimated intake of fish was considered for the period in which the infant was born. However, mothers who had grown up in a fishing village had an increased risk of having an infant with low birthweight (OR 2.1, 95% CI 1.0-4.3)., Conclusions: The variable "grown up in a fishing village" can be interpreted as an indirect measure of a mother's accumulated consumption of fish from the Baltic Sea. This idea supports an association between a high consumption of contaminated fish from the Baltic Sea and an increased risk for low birthweight. The effect estimates based on the mothers' reported fish consumptions were dependent on the period under consideration and therefore were somewhat ambiguous.

Objectives: The purpose of the study was to assess reproductive outcomes, especially birthweight, and the consumption of fatty fish from the Baltic Sea, contaminated with persistent organochlorine compounds, among women from the Swedish east coast., Material and Methods: Cohorts of fishermen's wives from the Swedish east and west coasts were established and linked to the Swedish Medical Birth Register for 1973-1991; 1501 children were born in the eastcoast cohort and 3553 in the westcoast cohort. Comparisons were made with regional populations and between the cohorts. Dietary interviews were made with 69 randomly selected women from the cohorts and 69 referents., Results: The women interviewed from the east- and westcoast cohorts ate locally caught fish more than twice as often as their referents. Compared with the regional population, the women in the eastcoast cohort gave birth to an increased number of infants with low birthweights (< 3000 g), whereas the opposite was seen in the westcoast cohort. Infants in the eastcoast cohort had significantly lower birthweights than infants from the westcoast cohort (median 3530 versus 3610 g, P < 0.001). Even after adjustment for potential confounders, eastcoast affiliation showed an increased risk for low birthweight (odds ratio 1.44, 95% confidence interval 1.18-1.76). The effect was more conspicuous for boys (odds ratio 1.95) and heavy smokers (odds ratio 3.00)., Conclusions: The present data support, but do not prove, an association between a high consumption of contaminated fish from the Baltic Sea and an increased risk for low birthweight.

Objectives: The purpose of the present study was to assess the effect, on miscarriages and stillbirths, of persistent organochlorine compounds (POC) through dietary intake of fatty fish from the Baltic Sea. Methods: Information on miscarriages and stillbirths was collected retrospectively by a self-administered questionnaire in a cohort of fishermen's wives from the Swedish east coast (by the Baltic Sea) and in a referent cohort of west coast fishermen's wives. Current fish consumption was used as a proxy for exposure within the east coast cohort. Results: No increase in miscarriages or stillbirths was found in the east coast cohort compared with the west coast group, in fact a decrease in early miscarriages was found (OR 0.48 [95% CI 0.26–0.92]). Moreover, no increase in risk was found for current high consumers of fatty fish within the east coast cohort. Conclusions: The present data provided no evidence that dietary POC exposure increases miscarriage and stillbirth rates. [ABSTRACT FROM AUTHOR]