Bioaccumulation of hydroxylated polychlorinated biphenyls and pentachlorophenol in the serum of northern elephant seal pups (Mirounga angustirostris).

Northern elephant seals (NES) (Mirounga angustirostris) from the Año Nuevo State Reserve (CA, USA) were sampled at 1-, 4-, 7- and 10-week post-weaning. Concentrations of hydroxylated polychlorinated biphenyls (HO-PCBs) and their parent PCBs were measured in the serum of each individual. The ΣHO-PCB concentrations in the serum increased significantly between early and late fast (from 282 ± 20 to 529 ± 31 pg/mL). This increase might result from a mobilisation of HO-PCBs transferred from the mother during gestation and/or lactation and stored in the pup's liver. Food deprivation has been shown to exacerbate biotransformation capacities in mammals, birds and fish. The HO-penta-CBs was the predominant homologue group, followed by HO-hexa-CBs and HO-hepta-CBs. No preferential pathway for the metabolism of HO-PCBs (HO-direct insertion or NIH-shift of a chlorine atom) could be evidenced. The concentrations of pentachlorophenol (PCP) in the serum of weaned NES increased from 103 ± 7 pg/mL at early fast to 246 ± 41 pg/mL at late fast, which is within the range of PCP concentrations usually encountered in marine mammals.

Global trends and diversity in pentachlorophenol levels in the environment and in humans: a meta-analysis.

Pentachlorophenol (PCP) was banned or restricted in many countries worldwide because of its adverse effects on the ecological environment and humans. However, the endocrine disrupting effects caused by low environmental PCP exposure levels has warranted more analysis. We reviewed 80 studies conducted in 21 countries and published between 1967 and 2010, using meta-regression analysis to examine the time trends and regional differences in PCP levels. The results suggested that in indoor air, bodies of water, freshwater sediments in western countries, invertebrates and freshwater vertebrates, PCP levels had declined over time, with half-lives ranging from 2.0 years to 11.1 years. However, in marine sediments/vertebrates and Chinese surface water/sediments, PCP levels increased over time. PCP levels in human blood and urine had decreased since the 1970s, with population half-lives of 3.6 years and 5.7 years, respectively. The intervals for global population blood and urine reference values decreased to 1.1-6.3 µg/L (2002-2008) and 2.5-7 µg/L (1995-2003), respectively. The possible thyroid disrupting effects and other health risks correlated with low environmental PCP exposure should be concerning. This study can help to ascertain the effects of the banning/restriction policy, providing data for cost-benefit analysis in policy-making and further control of health risks caused by low environmental exposure to PCP.

Pentachlorobenzene, hexachlorobenzene, and pentachlorophenol in children's serum from industrial and rural populations after restricted use.

The study of a population of 4-year-old children born between 1997 and 1999 in an urban area under strong inputs of pentachlorobenzene (PeCB) and hexachlorobenzene (HCB) suggested that the measured concentrations of pentachlorophenol (PCP) in serum may essentially result from metabolism of these chlorinated hydrocarbons. In contrast, examination of a rural population of children where the same compounds were present at relatively low levels points to other inputs besides transformation of PeCB and HCB being responsible for the measured PCP concentrations. In both populations, the results showed that a major proportion of the organochlorine compounds present in these children's serum at 4 years of age was incorporated during the lactation period.

Polychlorinated biphenyls and their hydroxylated metabolites (OH-PCBS) in pregnant women from eastern Slovakia.

OBJECTIVE: Our aim in the present study was to characterize and quantify the levels of polychlorinated biphenyls (PCBs) and specific polychlorobiphenylol (OH-PCB) metabolites in maternal sera from women delivering in eastern Slovakia. DESIGN: During 2002-2004, blood samples were collected from women delivering in two Slovak locations: Michalovce district, where PCBs were formerly manufactured, and Svidnik and Stropkov districts, about 70 km north. PARTICIPANTS: A total of 762 and 341 pregnant women were sampled from Michalovce and Svidnik/Stropkov, respectively, and OH-PCBs were measured in 131 and 31. EVALUATION/MEASUREMENTS: We analyzed PCBs using gas chromatography (GC)/electron capture detection. OH-PCBs and pentachlorophenol (PCP) were determined as methyl derivatives using GC-electron capture negative ionization/mass spectrometry. We characterized distributions in the full cohort using inverse sampling weights. RESULTS: The concentrations of both PCBs and OH-PCB metabolites of Michalovce mothers were about two times higher than those of the Svidnik/Stropkov mothers (p < 0.001). The median weighted maternal serum levels of the sum of PCBs (sigmaPCBs) were 5.73 ng/g wet weight (Michalovce) and 2.82 ng/g wet weight (Svidnik/Stropkov). The median sum of OH-PCBs (ZOH-PCBs) was 0.55 ng/g wet weight in Michalovce mothers and 0.32 ng/g wet weight in Svidnik/Stropkov mothers. 4-OH-2,2',3,4',5,5',6-Heptachlorobiphenyl (4-OH-CB187) was a primary metabolite, followed by 4-OH-2,2',3,4',5,5'-hexachlorobiphenyl (4-OH-CB146). Only four PCB congeners-CBs 153, 138, 180, and 170--had higher concentrations than 4-OH-CB187 and 4-OH-CB146 (p < 0.001). The median ratio of the sigmaOH-PCBs to the sigmaPCBs was 0.10. CONCLUSIONS: Mothers residing in eastern Slovakia are still highly exposed to PCBs, and their body burdens of these pollutants and OH-PCB metabolites may pose a risk for adverse effects on health for themselves and their children.

Twenty years of the German Environmental Survey (GerES): human biomonitoring--temporal and spatial (West Germany/East Germany) differences in population exposure.

The German Environmental Surveys (GerESs) are nationwide population studies, which have repeatedly been carried out in Germany since the mid-1980s. The subjects were representatively selected from the regional registration offices with regard to age, gender and community size. The first survey for adults (GerES I) was carried out in 1985/1986 (West Germany) followed by GerES IIa in 1990/1991 (West Germany) and GerES IIb in 1991/1992 (East Germany). In GerES II children were also included to some extent. In 1998, the third GerES for adults was conducted in both parts of Germany (GerES III). The current survey 2003/2006 (GerES IV) is focussing exclusively on children. A 1-year pilot study was conducted in 2001-2002 to collect information on parameters influencing the response rate and to test the suitability of the different instruments intended to be used for the main study. The main goal of the surveys is to analyse and document the extent, distribution and determinants of exposure to environmental pollutants of the German general population. Three main instruments of investigation were comprised in GerES: human biomonitoring (HBM), monitoring of the domestic environment, and collecting information on exposure pathways and living conditions via questionnaires. This paper is focussed on the general design of the GerESs, the trend over time and spatial differences (West Germany and East Germany) for HBM data on arsenic, cadmium, lead, mercury, pentachlorophenol (PCP), and polycyclic aromatic hydrocarbons (PAH). These substances have been determined in blood and/or morning urine of adults and children. All GerESs have been conducted in close connection with the National Health Interview and Examination Surveys performed by the Robert Koch-Institute, Berlin.

Development of a solid phase microextraction-gas chromatography-mass spectrometry method for the determination of pentachlorophenol in human plasma using experimental design.

A new method, headspace solid-phase microextraction (HS-SPME) with in situ derivatization and gas chromatography-mass spectrometry (GC-MS), which was used for the determination of trace amount of pentachlorophenol (PCP) in human plasma was presented. The acetylation derivatization reaction was firstly optimized using a Doehlert design. Then a series of parameters relevant to the headspace SPME procedure, including fiber coating, extraction temperature, extraction time and salt addition, were optimized using a two-level full factorial design expanded further to a central composite design. The validation of method showed that the optimized method had good linearity (R(2)=0.999) within the concentration ranges 0.1-50.0ngml(-1), and was sensitive with the limit of detection of 0.02ngml(-1). Intra- and inter-day precision for pentachlorophenol in human plasma samples were not greater than 11.9% and 12.6%, respectively. The proposed method, to our knowledge, describes the first application of HS-SPME with GC-MS for analysis of PCP in blood plasma sample. Application of the method to real human plasma samples, PCP was successfully detected in some cases at concentration levels 1.2-6.3ngml(-1).

Residential and biological exposure assessment of chemicals from a wood treatment plant.

This paper evaluates the results of contamination of residents and residential homes located in close proximity to a Wood Treatment Plant. The plant has produced treated wood products continuously since 1904. The principle chemicals used to treat the wood, which is primarily used for railroad ties (oblong objects laid perpendicular to the rails to act as a base for the tracks), are creosote and pentachlorophenol. For a number of years, the plant burned treated waste wood products containing creosote and pentachlorophenol. First the plant pressure impregnates the wood with creosote and pentachlorophenol, and then the wood is stacked on open ground to allow it to air dry. Chemicals from recently treated wood ties are allowed to evaporate into the air or drip onto the ground surrounding the stacked wood. Small drainage ditches carry the liquid wastes into larger water channels where eventually the waste streams are discharged into a river adjacent to the plant. The river serves as a source of drinking water for the nearby community. Prevailing wind patterns favor a drift of air emissions from the plant's boiler stack over the nearby community and its residents. Over the past few years, the town's residents have become increasingly concerned about their health status and have voiced concerns regarding multiple health problems (including cancer), possibly associated with plant discharges. The intention of this study is to examine a representative sample of the potentially affected residents and to evaluate their residential environment for the presence of dioxin and/or its congeners. Data obtained from EPA's Toxic Release Information (TRI) database revealed the plant routinely discharged creosote, pentachlorophenol, dioxin and dioxin-like compounds into the ambient air via fugitive air emissions and surface waste waters. Sampling of household dust and water sediment within and outside of residences within a 2-mile radius of the plant revealed the presence of significantly elevated levels of dioxins, principally octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,6,7,8-hepta-CDD. Biomonitoring of 29 subjects identified the presence of significantly elevated chlorinated dioxins and furan levels (OCDD=1049 ppt for exposed and 374 ppt for controls and 1,2,3,4,6,7,8-hepta CDD=132 ppt for exposed and 45.1 ppt for controls). These levels are consistent with exposures to pentachlorophenol in this group of subjects. And they confirm the presence of unsafe levels of chlorinated dioxins in these persons.

Determination of phenolic organohalogens in human serum from a Belgian population and assessment of parameters affecting the human contamination.

Many in vitro or in vivo studies highlighted the potential deleterious effects of phenolic organohalogenated compounds (POHs) on the health, particularly on the thyroid system homeostasis, however few large scale human epidemiological studies have been carried out, especially in Europe. Further studies monitoring the human contamination by POHs, the sources of exposure and the influence of these compounds on thyroid health are still needed. Therefore we determined the concentrations of 16 POHs (pentachlorophenol (PCP), tetrabromobisphenol A (TBBPA), 4 bromophenols (BPs), 3 hydroxy-polybromodiphenylethers (OH-PBDEs) and 7 hydroxy-polychlorobiphenyls (OH-PCBs)) in serum from 274 people aged from 18 to 76years old living in Liege (Belgium) and the surrounding area. A questionnaire about their alimentary habits, life style and home environment was also administered to the volunteers. The predominant compound measured in the population was PCP (median concentration of 593.0pgmL-1). 4-OH-CB 107, 4-OH-CB 146 and 4-OH-CB 187 were detected in all samples and contributed for 75% of the sum of OH-PCBs (ΣOH-PCBs). The median measured in our population for ΣOH-PCBs was 143.7pgmL-1. TBBPA and 2,4,6-tribromophenol were detected in 31% and 63.8% of the samples respectively while the detection frequency observed for the other BPs and the OH-PBDEs was close to zero. We computed multivariate regression models in order to assess the influence of demographic and lifestyle parameters on the PCP and ΣOH-PCBs contamination levels. Significant correlation was found between the PCP concentration and sex, smoker status, sea fish consumption and level of education, although the model seemed to be a poor (R2=0.14) predictor of the PCP concentration. The model computed for ΣOH-PCBs was more explanatory (R2=0.61) and involved age, BMI and sea fish consumption. Finally, we assessed the parameters affecting the ΣOH-PCBs/ΣPCBs ratio. The model proposed involved age, BMI, smoker status and parent PCB level, and explained 41% of the variability of the ΣOH-PCBs/ΣPCBs ratio.

Validation of a novel and rapid method for the simultaneous determination of some phenolic organohalogens in human serum by GC-MS.

Over the last decades, more and more studies focused on the impact of endocrine disruptors on the environment and human health. Among them, phenolic organohalogens (POHs) are a particular concern because of their structural resemblance with natural hormones. There are different methods that are known to quantify these compounds in human serum, however, the current extraction techniques are long, fastidious and using harmfull chemicals such as diazomethane and sulfuric acid. Consequently, we developed an alternative, sensitive and faster method to simultaneously quantify pentachlorophenol (PCP), tetrabromobisphenol A (TBBPA), 4 bromophenols, 7 hydroxypolychlorinated biphenyls (OH-PCBs) and 3 hydroxy-polybrominated diphenyl ether (OH-PBDEs) in human serum sample. The clean-up and the enrichment of the sample were performed in a single extraction step using strong anion-exchange solid phase cartridge. After a rapid liquid-liquid extraction step to remove acidic traces, the extract was derivatized using trimethylsilyldiazomethane (TMSD) and finally analyzed by a gas-chromatograph coupled with an electron negative capture chemical ionization source combined with a triple quadrupole mass spectrometer (GC-ENCI-MS) operating in single ion monitoring. The whole procedure was validated according to the total error approach. The inter and intra assay precision were demonstrated to be lower than 20% and the relative bias to be lower than 15% in the dosing range of concentrations. The limit of quantification (LOQ) ranged from 2pgmL-1 and 5pgmL-1, except for the PCP (44.6pgmL-1) and for the 2,4,6-tribromophenol (49.6pgmL-1). Finally, the method was successfully applied to measure the POH background contamination in serum samples collected from 20 Belgian blood donors recruited in CHU Mont-Godinne (Namur, Belgium) aged between 21 and 69 years old.

Determination of hydroxylated polychlorinated biphenyls (HO-PCBs) in blood plasma by high-performance liquid chromatography-electrospray ionization-tandem quadrupole mass spectrometry.

Hydroxylated metabolites of polychlorinated biphenyls (HO-PCBs) and pentachlorophenol (PCP) are halogenated phenolic compounds, and they are increasingly common as environmental contaminants mainly in the blood of wildlife and humans. A methodology based on high-performance liquid chromatography (reversed-phase)-electrospray (negative) ionization-tandem quadrupole mass spectrometry (LC-ESI(-)-MS-MS) in the select ion monitoring or multiple reaction monitoring modes was developed for HO-PCB and PCP determination in blood plasma and serum. Among 11 environmentally relevant HO-PCB congeners and PCP spiked to fetal calf serum, quantitative assessments, including matrix effects on ESI(-) suppression/ enhancement, showed process (recovery) efficiencies of 73% to 89% without internal standard (IS) correction, and 88% to 103% with IS correction, and method limits of quantification ranging from 1 to 50 pg/g (wet weight). Using the developed LC-ESI(-)-MS methodology in comparison with GC-MS and GC-ECD based approaches, similar results were found for HO-PCB identification and quantification in the plasma of polar bear (Ursus maritimus) from the Canadian arctic. LC-ESI(-)-MS identified four HO-PCB congeners [4'-HO-2,2',4,6,6'-pentachlorobiphenyl (4'-HO-CB104), 4-HO-2,3,3',4',5-pentachlorobiphenyl (4-HO-CB107), 4-HO-2,3,3',5,5',6-hexachlorobiphenyl (4-HO-CB165) and 3'-HO-2,2',3,4,4',5,5'-heptachlorobiphenyl (3'-HO-CB180)], and 14 additional tetra- to hepta-chlorinated HO-PCBs isomers in the polar bear plasma.

Use of pentachlorophenol as long-term inhibitor of sulfation of phenols and hydroxamic acids in the rat in vivo.

Inhibition of sulfation of the phenolic compound harmol (7-hydroxy-1-methyl-9H-pyrido[3,4-b]indole) by pentachlorophenol (PCP) was studied in the Wistar rat: PCP was administered in various ways to find a convenient method for long-term inhibition of sulfation. High doses of PCP or sodium pentachlorophenolate (NaPCP) in the diet (350 ppm) or NaPCP in the drinking water (1.4 mM) of Wistar rats for one week inhibited the sulfation of harmol by 30-45%. The plasma concentration of PCP in rats with NaPCP (1.4 mM) in their drinking water was highest (270 microM) in the period that the animals were kept in the dark and consumed food and water. This is explained by a rapid elimination: the elimination of PCP from plasma, after intravenous administration, showed a biphasic disappearance curve with half-lives of 2.17 and 7.24 hrs, respectively. This is much faster than in Sprague-Dawley rats. A log-linear correlation was found between the plasma concentration of pentachlorophenol and the inhibition of harmol sulfation. Although administration of NaPCP to rats in their drinking water inhibited the sulfation of harmol only by 45%, it inhibited the sulfation of the carcinogenic arylhydroxamic acid N-hydroxy-2-acetylaminofluorene by 70-75%.

Hexachlorobenzene-induced hypothyroidism. Involvement of different mechanisms by parent compound and metabolite.

Rats received repeated oral treatment with different doses of hexachlorobenzene (HCB) (0-3.5 mmol/kg) for 2 or 4 weeks. Measurements of thyroid hormone status after 2 weeks showed a dose-dependent decrease of total thyroxine (TT4) levels, decreased free thyroxine (FT4) levels and little change of total triiodothyronine (TT3) levels. The effects on thyroid hormone status were more pronounced after 4 weeks and also included increased thyroid stimulating hormone (TSH) levels. These conditions suggest that HCB had induced hypothyroidism in these animals. Indications for occupation of thyroid hormone binding proteins were found in serum of exposed animals. The major metabolite pentachlorophenol (PCP) also caused, by competitive interactions with thyroid hormone binding proteins in serum, a rapid and dose-dependent decrease of TT4 and FT4 levels, but not of TT3 levels in serum. The decrease of serum TT4 levels by repeated dosing with 3.5 mmol HCB/kg for 4 weeks could be attributed to competitive interactions of PCP with hormone serum binding proteins and to increased metabolism induced by HCB to an equal degree. At lower dose levels or with shorter dosing periods, increased metabolism of T4 is the main cause of decreased TT4 serum levels. This is the first indication that a similar effect is caused simultaneously by the parent compound and its metabolite through different and independent mechanisms.

Chlorinated hydrocarbons in women with repeated miscarriages.

This study was conducted to investigate a possible etiological role of chlorinated hydrocarbons in the pathogenesis of repeated miscarriages. The blood levels of chlorinated hydrocarbons [CHCs: pentachlorophenol, hexachlorocyclohexane, hexachlorobenzene, the dichlorodiphenyltrichloroethane (DDT) group, polychlorinated biphenyls] were determined in 89 women with repeated miscarriages, who were referred to the University Hospital of Obstetrics and Gynecology of Heidelberg for investigations between 1989 and 1993, and compared to a previously investigated reference population. In more than 20% of the women, at least one of the CHC levels exceeded the reference range. CHC levels did not differ significantly between women with primary or secondary and early or late miscarriages; neither did they differ between women with hormonal or immunological disorders as causes of repeated miscarriages or women with idiopathic repeated miscarriages. No significant associations were detected between CHC levels and further conceptions or the outcome of further pregnancies. As significant associations were found between increasing CHC blood concentrations and immunological and hormonal changes, CHCs may have an impact on the pregnancy course in certain cases.

Human prenatal and postnatal exposure to polybrominated diphenyl ethers, polychlorinated biphenyls, polychlorobiphenylols, and pentachlorophenol.

The aim of this study was to determine human prenatal and postnatal exposures to polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), hydroxylated metabolites of PCBs (polychlorobiphenylols; OH-PCBs), and pentachlorophenol (PCP). The median PBDE fresh-weight concentrations in maternal and cord blood plasma and in breast milk were 24, 4.3, and 75 pg/g, respectively. The PCB concentrations were approximately 60 times higher in each compartment (1,560, 277, and 4,310 pg/g, respectively). Calculated on a lipid weight basis, the levels were comparable in maternal blood plasma and breast milk. In contrast to PCBs, differences were found between PBDE congener distribution in maternal and cord blood plasma. The OH-PCBs constituted up to 26% of the PCB levels in maternal blood plasma and 53% in cord blood plasma, with levels of 120 and 88 pg/g fresh weight, respectively, and in breast milk 3 pg/g. The corresponding concentrations for PCP were 2,830, 1,960, and 20 pg/g. The ratios of PCB to OH-PCB were 13, 3, and 1,400 in maternal, cord plasma, and breast milk, respectively. It is evident that prenatal exposures occur for all the analytes. Moreover, the exposure continues after birth via breast milk. However, levels of OH-PCBs and PCP in breast milk are low compared with levels in blood plasma. Exposures to both PCBs and PBDEs, and in particular to the endocrine-active halogenated phenolic compounds, are of concern and implicate a potential risk for developmental disturbances.

Pentachlorophenol concentrations in human cerebrospinal fluid.

Pentachlorophenol (PCP) is a widely applied insecticide and fungicide, particularly in wood preservation. Significant amounts of this compound have been reported in human serum, adipose tissue and urine. PCP is even found in people not occupationally exposed to this toxin or not living in PCP-treated log-houses. Substantial concentrations of this possible neurotoxic agent were detected in the cerebrospinal fluid (CSF) of 16 neurologic patients as measured by a high resolution gas chromatographic method using electron capture detection. This is the first report on PCP levels in (human) CSF. The observed level in CSF ranged from 0.24 up to 2.03 micrograms/L (ppb), with an average value of 0.75 +/- 0.49. The cerebrospinal fluid level did not correlate with the serum PCP concentration nor with the protein level of the cerebrospinal fluid.

Pharmacokinetic concepts in assessing intake of pentachlorophenol by rats after exposure through drinking water.

The objective of this study was to predict concentrations of a toxicant in plasma after exposure to the toxicant through drinking water using basic pharmacokinetic principles. As an example, we studied pentachlorophenol (PCP), a widely used wood preservative of public health concern as an environmental pollutant. We added PCP to the drinking water (30 micrograms/mL) of five rats for 3 days. Blood was sampled, and water consumption was monitored every 12 h on the days 1 and 2 and every 3 h on day 3. After a 4-day washout, a PCP dose of 2.5 mg/kg was given intravenously, and blood was withdrawn at selected times for 2 days. PCP concentrations in plasma were measured by capillary gas chromatography. A one-compartment model with zero-order input and kinetic parameters (clearance, volume of distribution, and bioavailability) estimated after intravenous administration adequately predicted PCP concentrations in plasma during exposure to PCP. The average steady-state concentration (Css), which reflects the overall exposure, was predicted using the clearance (CL) concept [i.e., Css = (bioavailability.rate of intake)/CL] and compared with the observed value. The data for PCP demonstrate the potential utility of CL and other kinetic concepts in assessing exposure to a toxicant in drinking water, food, or air.

Effects of drinking pattern on the peak/trough blood concentrations in drinking water studies.

The effects of changes in drinking patterns on the expected peak/trough blood concentrations of test compounds were examined during rodent dosed drinking water studies. They were based on the assumption that the kinetics of the test compound is linear and time-invariant. Results indicate that drinking patterns have minor effects on the expected peak/trough concentrations and the time to reach these concentrations. If a 12-hr light/dark cycle starting at 7.00 is used for all the drinking patterns studied, the peak and trough concentrations will occur in the early morning and late afternoon, respectively. A comparison of the predicted versus experimentally determined pentachlorophenol (PCP) plasma concentrations in a 1-wk rat drinking water study revealed that using a circadian rhythm drinking pattern in the model generated the most satisfactory prediction. Predictions based on a square wave drinking pattern with 90% drinking activities in the night phase were also excellent. Triangular or sinusoidal drinking patterns were least accurate in predictions.

Endocrine and reproductive function in ewes exposed to the organochlorine pesticides lindane or pentachlorophenol.

The effects of lindane (LIN, gamma-hexachlorocyclohexane) and pentachlorophenol (PCP) on reproduction and general endocrine function were examined in breeding ewes as a model for wild and domestic ungulates, which may be exposed to low levels of pesticides that are potential endocrine-disrupting chemicals. Ewes (n = 13/group) were fed either a control untreated diet (CON), or a diet treated with LIN (1 mg/kg/d) or PCP (1 mg/kg/d) during the 5 wk prior to mating and throughout pregnancy and lactation. Mating response, ovulation rate, follicle and corpus luteum size, gestation length, pregnancy rate, lambing rate, and lamb birth weight were recorded. After weaning, 6 ewes from each group were bled at 15-min intervals for 8 h during the day and night and for 1 h before and 5 h after i.v. administration of gonadotropin-releasing hormone, thyroid-stimulating hormone (TSH), and adrenocorticotropin, to measure serum concentrations of luteinizing hormone, follicle-stimulating hormone, thyroxine (T4), and cortisol. Ewes were then killed and endocrine tissues examined histologically. Pregnancy rate as a result of matings taking place at the synchronized estrus was significantly decreased by the lindane treatment However, PCP and lindane did not markedly affect any other aspect of reproductive function studied. In PCP-treated ewes, serum concentrations of T4 were significantly reduced compared to control ewes during the day and night; however, the T4 response to TSH was not altered by PCP treatment. No other measured endocrine parameters were consistently affected by lindane or PCP. Thyroid follicle size was significantly increased in the LIN and PCP ewes compared to the control ewes. Low serum concentrations of T4 in the PCP ewes may have resulted in increased TSH secretion and increased thyroid follicle size. In conclusion, although pesticide treatments had no serious adverse effects on reproductive function in breeding ewes, PCP reduced T4 concentration, which in the long term could influence reproductive and general performance.

Current internal exposure to pesticides in children and adolescents in Germany: blood plasma levels of pentachlorophenol (PCP), lindane (gamma-HCH), and dichloro(diphenyl)ethylene (DDE), a biostable metabolite of dichloro(diphenyl)trichloroethane (DDT).

Pesticides are widely used throughout the world in agriculture to protect crops, and in public health to control diseases transmitted by animal vectors or intermediate hosts. After the prohibition of organochlorines such as DDT internal exposure of the general population to the organochlorines has been reduced markedly. Herein, current internal exposure of children and adolescents in an urban area in Germany to PCP, lindane, and DDT/E is reported. One hundred and thirty children and adolescents took part in this voluntary investigation. All of them stated they had never used pesticides in their homes or for medical reasons. Blood plasma was analysed for pentachlorophenol (PCP), lindane (gamma-HCH), and dichloro(diphenyl)ethylene (DDE), a biostable metabolite of dichloro(diphenyl)trichloroethane (DDT), using gas chromatography/electron capture detection according to well established methods approved by the Deutsche Forschungsgemeinschaft. Median (and 95th percentiles) in the age groups < 6, 6- < 12, and 12- < 18 years of age were (microgram/l): DDE: 0.75 (4.45), 0.95 (5.04), 0.89 (8.77); DDT: < 0.1 (0.22), < 0.1 (0.25), < 0.1 (0.30); PCP: 2.48 (17.32), 2.69 (5.85), 2.08 (8.04); lindane: < 0.1 (0.12, < 0.1 (0.08), < 0.1 (0.09). High levels of internal exposure to DDT in two girls were probably obtained during a holiday stay in India; high PCP-levels in two other girls were caused by a leather jacket impregnated with PCP, and a holiday abroad, respectively. Current background levels of internal exposure to organochlorine insecticides in children and adolescents in Germany are quantified. Exposure to these substances in the general population is thought to occur mainly via residues in food, which are low in general, today. In special cases, however, individual exposures may be dominated by other sources, i.e. impregnated leather clothes.

PCP in the blood plasma: current exposure of the population in Germany, based on data obtained in 1998.

The fungicidal substance pentachlorophenol (PCP) had been used commonly for wood protection and leather impregnation in Germany until 1989, when this substance was prohibited by law. Hence, the body burden in the general population in Germany has been steadily declining. The reference values (95th percentiles) in blood plasma decreased from 20 micrograms PCP/l in 1991 to 12 micrograms/l in 1996. In 1998 the current exposure in a large residential population was investigated. 623 persons with an average age of 34.6 years (0-62 years) were investigated. For all of them there was neither evidence of occupational contact with PCP nor of the presence of PCP in the residential indoor environment. The mean PCP concentration in the plasma samples was 2.4 +/- 3.9 micrograms/l, the median 1.7 micrograms/l, and the 95th percentile 6.1 micrograms/l, the maximum value was 59.3 micrograms/l. In children and adolescents higher median and 95th percentiles were obtained than in adults (median 2.5 vs. 1.5 micrograms/l and 95th percentile 7.7 vs. 5.9 micrograms/l). All values above 20 micrograms/l were checked again individually: relationships with the level of PCP in household dust could not be detected. In one family leather clothing containing PCP, however, was found to be the cause of unusually high PCP values in the blood. Our investigations confirm a trend observed in recent years: exposure to PCP in the population in Germany decreases steadily and leads to an actualized reference value of 6.1 micrograms PCP/l plasma. In individual cases, however, greatly increased PCP levels in blood can still occur today, for example due to leather clothing treated with PCP.