German Environmental Survey 1998 (GerES III): environmental pollutants in blood of the German population

Case study: Possible differences in phthalates exposure among the Czech, Hungarian, and Slovak populations identified based on the DEMOCOPHES pilot study results

OBJECTIVE

Phthalates and their metabolites are classified as endocrine modulators. They affect the hormonal balance in both children and adults. The aim of this publication was to compare the urinary levels of phthalate metabolites in selected populations of the Czech Republic (CZ), Slovakia (SK), and Hungary (HU) in relation to the sources of phthalate exposure identified by means of questionnaire (personal care products, floor and wall coverings, plastic toys, and some kinds of foods).

METHODS

Data were obtained through the twin projects COPHES (COnsortium to Perform Human biomonitoring on a European Scale) and DEMOCOPHES (DEMOnstration of a study to COordinate and Perform Human biomonitoring on a European Scale) from 2009 to 2012. The target groups were children aged 6-11 years old and their mothers up to 45 years of age. The metabolites of phthalates (monomethyl phthalate (MMP), monoethyl phthalate (MEP), monobenzyl phthalate (MBzP), mono-cyclohexyl phthalate (MCHP), mono-(2-ethylhexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), and mono-(2-ethyl-5-oxohexyl) phthalate (5OXO-MEHP)) were analysed in first morning urine samples. After enzymatic glucuronide cleavage, the urine sample analyses were performed using ultra-high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) in one laboratory that qualified in the External Quality Assessment exercises organised by COPHES.

RESULTS

Significant differences in phthalate exposure between countries were revealed for children only but not for mothers. The concentrations of 5-OH-MEHP (P<0.001), 5OXO-MEHP (P<0.001), and their sum (P<0.001) were the highest in SK compared to CZ and HU. The health based guidance values for the sum of DEHP metabolites 5-OH MEHP and 5OXO-MEHP established by the German Commission for biomonitoring of 300 µg/L and 500 µg/L for women adults and children, respectively, were only exceeded in one mother and three boys. A significant difference was also found for MEP (P=0.0149), with the highest concentrations detected in HU. In all countries, the increasing frequency of using personal care products significantly elevated the concentrations of MEP.

CONCLUSION

Some differences were observed between countries in the concentrations of individual urinary phthalate metabolites in children. However, the questionnaire results give no direct explanation for the differences between the countries except the variation in using personal care products.

Baseline blood levels of manganese, lead, cadmium, copper, and zinc in residents of Beijing suburb

Baseline blood concentrations of metals are important references for monitoring metal exposure in environmental and occupational settings. The purpose of this study was to determine the blood levels of manganese (Mn), copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd) among the residents (aged 12-60 years old) living in the suburb southwest of Beijing in China and to compare the outcomes with reported values in various developed countries. Blood samples were collected from 648 subjects from March 2009 to February 2010. Metal concentrations in the whole blood were determined by ICP-MS. The geometric means of blood levels of Mn, Cu, Zn, Pb and Cd were 11.4, 802.4, 4665, 42.6, and 0.68 µg/L, respectively. Male subjects had higher blood Pb than the females, while the females had higher blood Mn and Cu than the males. There was no gender difference for blood Cd and Zn. Smokers had higher blood Cu, Zn, and Cd than nonsmokers. There were significant age-related differences in blood levels of all metals studied; subjects in the 17-30 age group had higher blood levels of Mn, Pb, Cu, and Zn, while those in the 46-60 age group had higher Cd than the other age groups. A remarkably lower blood level of Cu and Zn in this population as compared with residents of other developed countries was noticed. Based on the current study, the normal reference ranges for the blood Mn were estimated to be 5.80-25.2 μg/L; for blood Cu, 541-1475 μg/L; for blood Zn, 2349-9492 μg/L; for blood Pb, <100 μg/L; and for blood Cd, <5.30 μg/L in the general population living in Beijing suburbs.

Screening for childhood lead poisoning in the industrial region of Fez, Morocco

The study objectives were to estimate lead poisoning prevalence among children living next to an industrial area, to compare it to that in a control population, and to establish clinical and biological follow-up of the poisoned children. This is a descriptive cross-sectional study including 150 children (exposed and unexposed) performed between January 2012 and April 2013. It was meant to determine blood lead levels (BLLs) in children considered to be an exposed population (EP N 90), living in the industrial area Ain Nokb Fez compared with BLLs of children of other areas belonging to the same city supposed to be unexposed [UP (N = 60)]. A sociodemographic questionnaire was obtained, and a blood lead analysis was performed. Clinical and biological follow-up has been performed of poisoned children. The sample consisted of 90 EP children with an average age of 6.82 ± 3.32 years and male-to-female sex ratio (SR) of 1.5 and 60 UP children with an average age of 6.45 ± 3.29 years and an SR of 1.2. Among the 150 children recruited, the average of BLLs was 58.21 ± 36 µg/L (18-202.3 μg/L). The average of BLLs in EP children (71 ± 40 µg/L) was statistically greater (p < 0.0001) than that registered in UP children (38 ± 13 µg/L). All poisoned children belonged to the EP group at a prevalence of 21.1 %. The clinical and biological examinations of poisoned children showed a few perturbations such as anemia, hypocalcaemia, and deficiencies in magnesium and iron. No renal disease or objective neurological disorders were observed. In the follow-up of the children with BLL ≥100 µg/L (19 cases). BLL monitoring showed a significant decrease in average of blood concentration ranging from 136.75 ± 32.59 to 104.58 ± 32.73 µg/L (p < 0.0001) and in lead poisoning prevalence (p < 0.001), which decreased to 7.8 % from 21.1. Our study showed a high prevalence of lead poisoning (21.1 %) in EP children. The relocation of the industrial site associated with corrective and preventive measures has contributed to a decrease of exposure and lead poisoning prevalence in the aforementioned population.

Heavy metal toxicity and the environment

Heavy metals are naturally occurring elements that have a high atomic weight and a density at least five times greater than that of water. Their multiple industrial, domestic, agricultural, medical, and technological applications have led to their wide distribution in the environment, raising concerns over their potential effects on human health and the environment. Their toxicity depends on several factors including the dose, route of exposure, and chemical species, as well as the age, gender, genetics, and nutritional status of exposed individuals. Because of their high degree of toxicity, arsenic, cadmium, chromium, lead, and mercury rank among the priority metals that are of public health significance. These metallic elements are considered systemic toxicants that are known to induce multiple organ damage, even at lower levels of exposure. They are also classified as human carcinogens (known or probable) according to the US Environmental Protection Agency and the International Agency for Research on Cancer. This review provides an analysis of their environmental occurrence, production and use, potential for human exposure, and molecular mechanisms of toxicity, genotoxicity, and carcinogenicity.

Trend of blood lead, mercury, and cadmium levels in Korean population: data analysis of the Korea National Health and Nutrition Examination Survey

This study was performed to assess the recent trends in lead, mercury, and cadmium levels in the blood among Korean adult population. The geometric means and 95 % confidence intervals (CIs) of blood lead, mercury, and cadmium concentrations were calculated using the data of the subjects from the third (2005, n = 1997), fourth (2008, n = 2005; 2009, n = 1991), and fifth (2010, n = 1989; 2011, n = 2014) Korea National Health and Nutrition Examination Survey. Blood lead levels in 2005, 2008, 2009, 2010, and 2011 declined to 2.61 μg/dL (2.51-2.71), 2.32 μg/dL (2.27-2.37), 2.29 μg/dL (2.23-2.35), 2.09 μg/dL (2.04-2.13), and 1.99 μg/dL (1.94-2.05), respectively. Blood mercury levels were 4.19 μg/L (3.99-4.39), 4.73 μg/L (4.57-4.89), 4.25 μg/L (4.09-4.41), 3.64 μg/L (3.49-3.80), and 3.08 μg/L (2.95-3.22), respectively, which indicated an increase in 2008 compared with those in 2005, and a clear downward trend from 2008 to 2011. Blood cadmium levels were 1.52 μg/L (1.47-1.57), 0.93 μg/L (0.89-0.97), 0.94 μg/L (0.90-0.98), 0.89 μg/L (0.87-0.92), 0.86 μg/L (0.83-0.89), respectively, which indicated very high levels in 2005, but a downward trend since 2008. Although the lead, mercury, and cadmium levels in the blood of the Korean adult population are on the decline, they are still relatively high compared with those for the population of the USA, Canada, and Germany. Thus, continuous biological monitoring and measures to reduce these levels are needed in Korea.

Study on polychlorobiphenyl serum levels in French consumers of freshwater fish

INTRODUCTION

Polychlorobiphenyls (PCBs) are persistent pollutants that are widespread in the environment and in foodstuffs, particularly in freshwater fish, which frequently exceed the maximum levels set by European regulations.

OBJECTIVES

First, we describe the consumption of freshwater fish and serum PCB levels in French anglers, a population expected to have the highest level of dietary PCB exposure. Second, we investigated whether there is a statistical relationship between serum PCB levels and the angler consumption of freshwater fish with high PCB bioaccumulation potential (PCB-BP(+) freshwater fish) in order to make recommendations with regard to safe consumption of freshwater fish.

METHODS

We conducted a survey of anglers from six sites with contrasting PCB contamination levels. The survey included a food consumption frequency questionnaire and blood samples were taken to assess serum PCB levels. We used a regression model to determine the main factors contributing to serum PCB levels.

RESULTS

Consumption of PCB-BP(+) freshwater fish was relatively infrequent. Serum PCB levels of the study population and of women of childbearing age were in the same range as those observed in the French population and in neighbouring European countries, but higher than in the North American population. The two factors with the highest positive association with serum PCB levels were age (R(2)=61%) and the consumption of PCB-BP(+) freshwater fish (R(2)=2%). Using the regression model, we calculated, for several scenarios depending on the age and gender of the population, the maximum annual frequencies for PCB-BP(+) freshwater fish consumption that do not exceed the critical body burden threshold.

CONCLUSION

Following the results of this study, the French agency for food, environmental and occupational health and safety (ANSES) issued an opinion and recommended some specific maximum freshwater fish consumption frequencies to protect the French general population.

Risk factors for lead exposure in adult population in southern Brazil

In Brazil there is no systematic evaluation to access blood lead levels (BLL) in the general population and few studies with adults have been published. The aim of this study was to examine the socioeconomic, environmental, and lifestyle determinants of BLL in the adult Brazilian population. In total, 959 adults, aged 40 years or more, were randomly selected in a city in southern Brazil. Information on socioeconomic, dietary, lifestyle, and occupational background was obtained by interviews. A spatial analysis was conducted to discern whether there were any identifiable sources of exposure. BLL were measured by inductively coupled plasma-mass spectrometry. There was an adjustment for gender, age, race, education, income class, smoking status, alcohol consumption, occupation, and red meat or cow milk consumption (Model 1), and for occupation and gender (Model 2). The geometric mean of BLL was 1.97 μg/dl (95% CI: 1.9-2.04 μg/dl). In Model 1, BLL were positively associated with male gender, older age, and drinking and smoking habits, and less frequently with milk consumption. In Model 2, data showed higher BLL in non-white than white participants, in former smokers and individuals with current or former employment in lead (Pb) industries. The participants living in the area with more Pb industries had higher BLL (3.3 μg/dl) compared with those residing in other areas with no or fewer Pb industries (1.95 μg/dl). Despite the low BLL found in adults living in an urban area, Pb industries need to be monitored and regulatory laws implemented to prevent metal contamination in urban settings.

Environmental exposures, socioeconomics, disparities, and the kidneys

Kidney disease disproportionately affects racial and ethnic minority populations, the poor, and the socially disadvantaged. The excess risk of kidney disease among minority and disadvantaged populations can only be partially explained by an excess of diabetes, hypertension, and poor access to preventive care. Disparities in the environmental exposure to nephrotoxicants have been documented in minority and disadvantaged populations and may explain some of the excess risk of kidney disease. High-level environmental and occupational exposure to lead, cadmium, and mercury are known to cause specific nephropathies. However, there is growing evidence that low-level exposures to heavy metals may contribute to the development of CKD and its progression. In this article, we summarize the excess risk of environmental exposures among minority and disadvantaged populations. We also review the epidemiologic and clinical data linking low-level environmental exposure to lead, cadmium, and mercury to CKD and its progression. Finally, we briefly describe Mesoamerican nephropathy, an epidemic of CKD affecting young men in Central America, which may have occupational and environmental exposures contributing to its development.

Persistent organic pollutants (POPs) and metals in primiparous women: a comparison from Canada and Mexico

Under the North American Commission for Environmental Cooperation (CEC) and its Sound Management of Chemicals (SMOC) program, a tri-national human contaminant monitoring initiative was completed to provide baseline exposure information for several environmental contaminants in Canada, Mexico and the United States (U.S). Blood samples were collected from primiparous women in Canada and Mexico, and were analysed for a suite of environmental contaminants including polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene(p,p'-DDE),beta-hexachlorocyclohexane (β-HCH), mercury and lead. A multiple stepwise linear regression analysis was conducted using data from Canadian and Mexican primiparous mothers, adjusting for ethnicity group, age, pre-pregnancy BMI, years at current city and ever-smoking status. Concentrations of p,p'-DDE, β-HCH, and lead were found to be higher among Mexican participants; however, concentrations of most PCBs among Mexican participants were similar to Canadian primiparous women after adjusting for covariates. Concentrations of total mercury were generally higher among Mexican primiparous women although this difference was smaller as age increased. This initial dataset can be used to determine priorities for future activities and to track progress in the management of the selected chemicals, both domestically and on a broader cooperative basis within North America.

Relationship between serum ferritin level and blood mercury concentration using data from the Korean national health and nutrition examination survey (2010-2012)

BACKGROUND

Studies on the association between serum ferritin levels (S-Ft) and blood mercury concentrations (B-Hg) are scarce. The objective of this study was to investigate the relationships between these two parameters using a large-scale nationwide representative sample of the Korean males.

METHOD

A nationwide cross-sectional study was conducted to examine the relationship between S-Ft and B-Hg in 2832 men over 19 years of age (aged 20-87 years), using data from the 2010-2012 Korean National Health and Nutrition Examination Survey. The odds ratios (ORs) and 95% confidence intervals (CIs) for high B-Hg (>75th percentile) were calculated across S-Ft quartiles using multiple logistic regression analyses.

RESULTS

Mean values of B-Hg gradually increased in accordance with the quartiles of S-Ft (P-trend<0.001). The odds ratio (95% CI) for high B-Hg with the doubling of S-Ft was 1.51 (1.25-1.84) after adjusting for age, fish/shellfish consumption, rice consumption, waist circumference, cigarette smoking, alcohol intake, regular exercise, blood pressure, fasting plasma glucose, triglyceride, and high-density lipoprotein cholesterol. Compared with the lowest quartiles of B-Hg, the ORs (95% CI) for high S-Ft in the 3rd and 4th quartiles were 2.09 (1.17-3.73) and 2.73 (1.55-4.79) after adjusting for the same co-variables.

CONCLUSION

We found a positive relationship between S-Ft and B-Hg in a representative population sample of Korean adult men. Our results suggested S-Ft as a tool for environmental Hg exposure assessment.

Serum PCB levels in a representative sample of the Spanish adult population: the BIOAMBIENT.ES project

This manuscript presents the levels of six indicator polychlorinated biphenyl (PCB) congeners (IUPAC nos. 28, 52, 101, 138, 153 and 180) in the serum of 1880 individuals from a representative sample of the Spanish working population recruited between March 2009 and July 2010. Three out of the six PCBs studied (180, 153 and 138) were quantified in more than 99% of participants. PCB 180 was the highest contributor, followed by PCBs 153 and 138, with relative abundances of 42.6%, 33.2% and 24.2%, respectively. In contrast, PCBs 28 and 52 were detected in only 1% of samples, whereas PCB 101 was detectable in 6% of samples. The geometric mean (GM) for ΣPCBs138/153/180 was 135.4 ng/g lipid (95% CI: 121.3-151.2 ng/g lipid) and the 95th percentile was 482.2 ng/g lipid. Men had higher PCB blood concentrations than women (GMs 138.9 and 129.9 ng/g lipid respectively). As expected, serum PCB levels increased with age and frequency of fish consumption, particularly in those participants younger than 30 years of age. The highest levels we found were for participants from the Basque Country, whereas the lowest concentrations were found for those from the Canary Islands. The Spanish population studied herein had similar levels to those found previously in Greece and southern Italy, lower levels than those in France and central Europe, and higher PCB levels than those in the USA, Canada and New Zealand. This paper provides the first baseline information regarding PCB exposure in the Spanish adult population on a national scale. The results will allow us to establish reference levels, follow temporal trends and identify high-exposure groups, as well as monitor implementation of the Stockholm Convention in Spain.

Priority persistent contaminants in people dwelling in critical areas of Campania Region, Italy (SEBIOREC biomonitoring study)

To investigate if protracted living in degraded environments of the Caserta and Naples provinces (Campania Region, Italy) had an impact on exposure of local people, highly toxic persistent contaminants were measured in blood, blood serum, and human milk of a large number of healthy donors. Sampling was carried out from 2008 to 2009. Blood was collected from over 850 20-64-year old donors; by pooling, 84 blood and 84 serum samples were obtained. Milk was donated by 52 mothers: specimens were pooled into six samples. Polychlorodibenzodioxins (PCDDs), polychlorodibenzofurans (PCDFs), and polychlorobiphenyls (PCBs, dioxin-like (DL) and non-dioxin-like (Σ6PCBs)), arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) were measured in serum (organic biomarkers) and blood (metals); these chemicals and polybromobiphenyl ethers (Σ9PBDEs) were analyzed in milk. PCDD+PCDF, DL-PCB, TEQTOT, and Σ6PCB concentration ranges (medians) in serum were 6.26-23.1 (12.4), 3.42-31.7 (11.5), 10.0-52.8 (23.9) pgTEQ97/g fat, and 55.5-647 (219) ng/g fat, respectively, while in milk concentration ranges were 5.99-8.77, 4.02-6.15, 10.0-14.2 pgTEQ97/g fat, and 48.7-74.2 ng/g fat. Likewise, As, Cd, Hg, and Pb findings in blood spanned 2.34-13.4 (5.83), 0.180-0.930 (0.475), 1.09-7.60 (2.60), 10.2-55.9 (28.8) μg/L, respectively; only Pb could be measured in milk (2.78-5.99 μg/L). Σ9PBDE levels in milk samples were 0.965-6.05 ng/g fat. Biomarkers' concentrations were found to be compatible with their current values in European countries and in Italy, and consistent with an exposure primarily determined by consumption of commercial food from the large distribution system. Based on relatively higher biomarker values within the hematic biomonitoring database, the following municipalities were flagged as possibly deserving attention for health-oriented interventions: Brusciano and Caivano (As), Giugliano (Hg), Pianura (PCDDs+PCDFs), and Qualiano-Villaricca (As, Hg). The analysis of samples' qualitative variability indicated that biomarker composition was sensitive at municipality level, a feature that can potentially drive interventions for future local risk assessment and/or management measures.

Trace metals in blood and urine of newborn/mother pairs, adolescents and adults of the Flemish population (2007-2011)

The Flemish Centre for Environment and Health started with human biomonitoring in 2002 (FLEHS I: 2002-2006). The main goal of the second human biomonitoring cycle (FLEHS II: 2007-2011), was to determine mean values for a large number of pollutants in a representative sample of the general Flemish population. Values for Cd and Pb were updated, and a group of previously undetermined metals and metalloids (As, Mn, Cu and Tl) were included in some of the age groups. In this human biomonitoring program, three different age groups of the general Flemish population were monitored: 255 newborns and their mothers, 210 adolescents aged 14-15, and 204 adults between 20 and 40 years old. Trace elements were determined in cord blood and maternal blood of the mothers, in blood and urine of adolescents and in urine of adults. Determinants of life-style and personal factors were taken into account. The levels of trace elements in cord blood and maternal blood were for most elements at the lower end of the range found in literature. For Pb, As and Tl, a strong correlation (respectively r=0.43, 0.55 and 0.33; p<0.05) was found between levels in cord blood (respectively 8.6, 0.54 and 0.017 μg/L) and maternal blood (11.1, 0.64 and 0.028 μg/L), indicating that they are transported via the placenta from mother to fetus. The levels found in the adolescents and adults were compared with results from international biomonitoring studies, and were found to be in the same ranges. With the exception of Pb, all trace elements increased with increasing age group population. Finally, the results also showed that the levels of Cd and Pb in blood for this campaign (e.g. for Pb 8.6 and 14.8 μg/L in neonates and adolescents respectively) were lower compared to the first campaign (e.g. for Pb 14.7 and 21.7 μg/L in neonates and adolescents respectively), indicating a decrease over time. However, differences in sampling strategies might partially explain this observed trend.

Prevalence and incidence rates of mental syndromes after occupational exposure to polychlorinated biphenyls

Mental disorders were often reported following hazardous substance exposure. The present study analyses this association in relation to a work-related exposure to PCBs (polychlorinated biphenyls). Specifically, the aim was to investigate (a) the relationship of inner PCB burden and the severity of mental symptoms and (b) the prevalence and incidence of mental syndromes. This study was initiated as part of the occupational medical surveillance program HELPcB (Health Effects in high level exposure to PCB). A total of 136 individuals were included in the analysis. The plasma PCBs were collected via biomonitoring and the psychological syndromes (i.e., somatoform, depressive, anxiety, panic) with a standardized screening instrument. The relationship of PCB and the severity of mental syndromes were analyzed via linear regression. Prevalence rates, the respective odds ratios (OR) and the incidence rates were calculated with logistic regressions. We thereby compared the higher-PCB burdened individuals with those individuals showing PCB levels comparable to the general population. We found especially a significant relationship between PCB burden and depressivity. Within the higher-PCB-exposed group prevalence rates were descriptively higher than for normal-exposed participants, except for anxiety syndrome. Similarly, the higher exposed group had a higher risk for developing a depressive syndrome. The incidence rates were always descriptively higher in higher-exposed group. To summarize, this study supports a relationship between PCB exposure and mental illness.

Blood cadmium concentration of residents living near abandoned metal mines in Korea

The purpose of this study was to investigate demographic and lifestyle variables and blood cadmium concentrations in residents living near abandoned metal mines in Korea. Blood cadmium concentrations were measured in 15,161 subjects living around abandoned metal mines (exposed group, n = 14,464) and compared with those living in designated control areas (control group, n = 697). A questionnaire was provided to all subjects to determine age, gender, mine working history, times of residence, smoking habits and dietary water type. The geometric mean (95% confidence intervals) of blood cadmium concentration (1.25 [1.24-1.27] µg/L) in the exposed group was significantly higher than in the control group (1.17 [1.13-1.22] µg/L). Mean residence time and mine working history in the exposed group were significantly higher than in the control group. Blood cadmium concentrations increased with increasing age, and residence time in both groups, and blood cadmium concentrations were higher in current-smokers than in non-smokers in both groups. This study shows the geometric mean of blood cadmium concentration in abandoned mining areas are higher than in non-mining areas in the general adult Korean population.

Impacts of atmospheric chlor-alkali factory emissions in surrounding populations

Environmental exposures need to be assessed for the understanding of the health risks of general population. Organochlorine compounds (OCs) from chlor-alkali plants (CAPs) are significant for the exposomes of individuals living in locations receiving their emissions and have to be determined. The aims of the study are to identify the area of influence of past and present OC emissions from CAPs and to set quantitative body burden estimates. A CAP situated in a rural area was selected for study. The geographic distribution of the atmospheric emissions was monitored using olive tree leaves. Human biomonitoring was assessed by serum analysis from general population (n=1340). OC concentrations followed exponential decay functions with maxima in the immediate vicinity of the factory. The individuals living within 1km exhibited hexachlorobenzene (HCB), polychlorobiphenyls (PCBs) and DDT-DDE (dichlorodiphenyltrichloroethane-dichlorodiphenyldichloroethylene) concentrations that were 12, 1.3-1.9 and 3.9 times higher than in sites not influenced by the emissions from this factory. Individuals from municipalities situated 15-25km away from the CAP showed 1.5, 1.2-1.4 and 1.3 times higher serum HCB, PCB and DDT concentrations than in distant sites. The high serum concentrations of DDT and PCBs were observed even 23-31years and 9-17years after manufacture completion of these compounds, respectively. Our methodology provides a way for assessment of the influence of past and present atmospheric OCs emissions from CAPs into the exposome of individuals living in nearby areas.

Serum levels of organochlorine pesticides in the French adult population: the French National Nutrition and Health Study (ENNS), 2006-2007

BACKGROUND

Although most organochlorine (OC) pesticides were banned in France in the 1970s and 1980s, they remain a source of public concern. Because of their high persistence in the environment, they are still detected in foodstuffs, leading to continued human exposure. The purpose of this study was to assess the distribution of serum organochlorine (OC) pesticides in the French adult population and to identify the main risk factors for p,p'-dichlorodiphenyl dichlorethylene (DDE), β-hexachlorocyclohexane (β-HCH) and hexachlorobenzene (HCB).

METHOD

The selected OC pesticides (HCB, DDE, DDT, α-HCH, β-HCB and γ-HCH) were measured in serum samples collected in 2006-2007 from 386 persons (aged 18-74 years) randomly selected among the participants in the clinical and biological component of the French Nutrition and Health Survey (Etude Nationale Nutrition Santé [ENNS]), a cross-sectional survey carried out in the general population. Collected data included biological samples, socio-demographic characteristics, and data about environmental and occupational exposure factors.

RESULTS

Of the six OC pesticides investigated, the highest concentrations were observed for HCB, β-HCH and DDE. Median serum concentrations were as follows: 22.8 ng/g lipid for HCB, 0.74 and 27.0 ng/g lipid, respectively, for α- and ß-HCH, and 3.8 and 104.6 ng/g lipid, respectively, for DDT and DDE. Lindane (γ-HCH) was detected in approximately 10% of the sample. OC pesticide levels in serum in French adults were higher (except for DDT and DDE) than those observed in American, Canadian and German populations and generally lower than or in the same range as those observed in other European countries. The low serum DDT/DDE ratio in the present study (3.7%) would suggest that the concentrations observed for these two OC pesticides were mainly the result of past exposure. The most important predictors of serum DDE, HCB and β-HCH concentrations among the French adult population included individual factors (age, gender, BMI, etc.), dietary factors of animal and vegetable origin, and domestic use of pesticides (in vegetable gardens and/or fruit trees).

CONCLUSION

For the first time in France, a human biomonitoring study has shown that exposure to OC pesticides remains common in the population. French concentrations were higher (except for DDT and DDE) or were similar to those observed in other developed countries.

Reference values of lead in blood and related factors among blood donors in the Western Amazon, Brazil

The aim of this study was to (1) determine the reference value of blood lead levels (BLL) in a sample of blood donors of Rio Branco, the capital city of Acre, in the Western Brazilian Amazon, and (2) explore factors influencing lead (Pb) exposure levels. Between 2010 and 2011, blood samples were collected from universal blood donors attending the Central Hemotherapic Unit in Rio Branco with a total number of 1196. Information on characteristics of 1183 donors was obtained through questionnaires. Blood Pb concentrations were determined by inductively coupled plasma-mass spectrometry with detection limit of 0.003 μg/L. Association between BLL and participant characteristics was examined by linear regression analysis. Reference values of BLL were calculated as the upper limit of the 95% confidence interval of the 95th percentile. Reference values of BLL were 109.5 μg/L for men, 70.7 μg/L for women, 88.9 μg/L for younger individuals (18-29 yr), 115.3 μg/L for older ones (≥30 yr), 94.2 μg/L for nonsmokers, and 164.5 μg/L for smokers. Levels of BLL were significantly higher in males, subjects older than 29 yr, non-whites, smokers, regular consumers of manioc flour, and donors practicing any activity related to paints, ceramics, pottery, fishing, or firearms. Subjects with higher education, higher income, vitamin intake use, and drinkers of bottled water displayed lower BLL. In general, BLL in men and women from Rio Branco were higher than those described in other adult populations. Prevention of exposure of this population to local sources of Pb needs to be addressed.

Relative effects of educational level and occupational social class on body concentrations of persistent organic pollutants in a representative sample of the general population of Catalonia, Spain

Scant evidence is available worldwide on the relative influence of occupational social class and educational level on body concentrations of persistent organic pollutants (POPs) in the general population. The objective was to analyse such influence in a representative sample of the general population of Catalonia, Spain. Participants in the Catalan Health Interview Survey aged 18-74 were interviewed face-to-face, gave blood, and underwent a physical exam. The role of age, body mass index (BMI), and parity was analysed with General Linear Models, and adjusted geometric means (GMs) were obtained. Crude (unadjusted) concentrations were higher in women and men with lower education, and in women, but not men, in the less affluent social class. After adjusting for age, in women there were no associations between POP levels and social class or education. After adjusting for age and BMI, men in the less affluent class had higher p,p'-DDE concentrations than men in class I (p-value=0.016), while men in class IV had lower HCB than men in the upper class (p-value<0.03). Also in contrast with some expectations, positive associations between education and POP levels were observed after adjusting for age and BMI in men; e.g., men with university studies had higher HCB concentrations than men with first stage of primary schooling (adjusted GM 153.9 and 80.5ng/g, respectively) (p-value<0.001). When education and social class were co-adjusted for, some positive associations with education in men remained statistically significant, whereas class remained associated only with p,p'-DDE. Educational level influenced blood concentrations of POPs more than occupational social class, especially in men. In women, POP concentrations were mainly explained by age/birth cohort, parity and BMI. In men, while concentrations were also mainly explained by age/birth cohort and BMI, both social class and education showed positive associations. Important characteristics of socioeconomic groups as age and BMI may largely explain crude differences among such groups in internal contamination by POPs. The absence of clear patterns of relationships between blood concentrations of POPs and indicators of socioeconomic position may fundamentally be due to the widespread, lifelong, and generally invisible contamination of human food webs. Decreasing historical trends would also partly explain crude socioeconomic differences apparently due to birth cohort effects.

Four cases of abnormal neuropsychological findings in children with high blood methylmercury concentrations

Background

Methylmercury (MeHg) easily crosses the blood–brain barrier and accumulates in the brain. Accumulated MeHg will cause neurological symptoms. We report four pediatric cases of neuropsychological findings with high blood MeHg concentrations.

Case presentation

Four children were admitted for follow-up study because their total mercury (THg) concentration in the blood was found to be high during a national survey. Case 1 was a 9-year-old female with a 16.6 μg/ℓ blood THg concentration in the survey. During admission, the blood THg, hair THg, and blood MeHg concentration(mercury indices) were 21.4 μg/ℓ, 7.2 μg/g, and 20.1 μg/ℓ, respectively. In our neuropsychological examination, cognitive impairment and attention deficit were observed. Her diet included fish intake 2–3 times per week, and she had been diagnosed with epilepsy at 3 years of age. Case 2 was a 12-year-old male with blood THg of 15.4 μg/ℓ in the survey and the mercury indices were 12.7 μg/ℓ, 5.7 μg/g, and 11.8 μg/ℓ, respectively, on admission. He was also observed to have attention-deficit/hyperactivity disorder. Case 3 was a 10-year-old male child with blood THg of 17.4 μg/ℓ in the survey, and the mercury indices on admission were 21.6 μg/ℓ, 7.5 μg/g and 21.5 μg/ℓ, respectively. In his case, mild attention deficit was observed. Case 4 was a 9-year-old male with blood THg of 20.6 μg/ℓ in the survey and the mercury indices were 18.9 μg/ℓ, 8.3 μg/g, and 14.4 μg/ℓ, respectively, on admission. Mild attention difficulty was observed.

Conclusion

We suggest that fish consumption may be the main source of MeHg exposure, and that MeHg may have been the cause of the neuropsychological deficits in these cases.

Reference levels of blood mercury and association with metabolic syndrome in Korean adults

PURPOSE

Mercury (Hg) is a nonessential and toxic metal that is widely distributed in the environment. This study was performed to estimate the representative blood Hg level, to determine the contributing factors to Hg exposure, and to analyze the association of blood Hg with metabolic syndrome in Korean adults.

METHODS

Mercury exposure is assessed by total Hg concentration in blood. A total of 2,114 healthy adults who have not been exposed to Hg occupationally were sampled by the multistaged, sex-, and age-stratified probability method. Information was collected regarding the subjects' demographic characteristics, lifestyles, and past medical history. The participants then underwent physical examination and blood sampling.

RESULTS

The geometric mean concentration of Hg in whole blood was 3.90 μg/L, which was significantly influenced by sex, age, smoking, alcoholic consumption, residence area, and seafood intake after adjustment for confounders. Significant increases in body mass index, waist circumference, diastolic blood pressure, total cholesterol, and triglyceride were observed according to the blood Hg levels after adjustment for covariates. Also, Hg exposure was significantly associated with metabolic syndrome and their components such as obesity and increased fasting glucose.

CONCLUSION

The blood Hg level in Korean adults is higher than that in USA and other Western countries, while it is similar to or lower than that in other Asian countries. The blood Hg level is influenced by sociodemographic factors and individual lifestyles including dietary habits. Furthermore, blood Hg is associated with metabolic syndrome, in which Hg exposure may play a role as a possible risk factor for cardiovascular diseases.

Blood mercury concentration among residents of a historic mercury mine and possible effects on renal function: a cross-sectional study in southwestern China

This cross-sectional study aimed to investigate blood mercury (B-Hg) concentration of residents living in the vicinity of Chatian mercury mine (CMM) in southwestern China and to assess the possible effects on renal function. It evaluates the effects of gender and age (children, <18 years; adults, 18-60 years; elderly, >60 years) on the B-Hg and serum creatinine (SCR) and serum urea nitrogen (SUN) levels. In the CMM, elevated levels were found for B-Hg, SCR, and SUN with mean values at 6.09 μg/L, 74.21 μmol/L, and 13.26 mmol/L, which were significantly higher than those in the control area, respectively. Moreover, the coefficients between paired results for B-Hg and SCR and SUN levels were positive at statistical significance (B-Hg vs. SCR, r = 0.45, p < 0.01; B-Hg vs. SUN, r = 0.20, p < 0.05). The aforementioned results revealed that mercury exposure can cause human renal function impairment. B-Hg, SCR, and SUN can also be useful biomarkers to assess the extent of mercury exposure among residents in areas with extensive mining activities. Furthermore, data analysis revealed that there was a tendency for higher B-Hg, SCR, and SUN levels in females than in males, and the levels of B-Hg, SCR, and SUN increased among the older residents. We conclude that females and the elderly in the mining area were more susceptible to mercury exposure, and therefore, they deserve further research.

Blood total mercury concentrations in the Canadian population: Canadian Health Measures Survey cycle 1, 2007-2009

OBJECTIVES

We present total mercury (THg) in blood of Canadians 6-79 years of age from the first to-date nationally-representative survey, the Canadian Health Measures Survey (CHMS). This analysis is particularly relevant in the context of recent changes to Health Canada's blood Hg guidance values.

METHODS

We used data from cycle 1 (2007-2009) of the CHMS, in particular focussing on 5,319 respondents aged 6-79 years for whom blood THg data were available. We calculated descriptive statistics of blood Hg levels and analyzed the associations between blood THg levels and relevant variables. We also compared blood THg levels to existing Health Canada blood Hg guidance values.

RESULTS

The geometric mean blood THg level of the Canadian population was 0.69 µg/L (95% CI 0.56-0.86 µg/L). The majority (97.8%) of Canadian women aged 16-49 years, including pregnant women, had blood Hg values below the provisional HC blood guidance value of 8 µg/L. Mean blood THg levels were significantly higher in the "other or mixed" (1.14 µg/L, p=0.0003) and Asian (1.41 µg/L, p=0.0476) groups compared to those who self-identified as solely Caucasian (0.62 µg/L). There was however no significant difference between participants self-identified as Aboriginal Canadians versus Caucasians (0.56 µg/L vs 0.62 µg/L, p=0.2902).Fish and shellfish consumption significantly influenced blood Hg levels, as did alcohol consumption and the presence of dental amalgams.

CONCLUSION

This paper presents the first description of blood THg levels in the general Canadian population. These findings will serve as a national baseline for monitoring future changes should they arise.

Distributions and determinants of mercury concentrations in toenails among American young adults: the CARDIA Trace Element Study

Since data on mercury (Hg) levels in Caucasians and African Americans (AAs) of both genders are lacking, this study aims to present toenail Hg distributions and explore the potential determinants using data from the Coronary Artery Risk Development in Young Adults Trace Element Study. Data from 4,344 Americans, aged 20-32 in 1987, recruited from Oakland, Chicago, Minneapolis, and Birmingham were used to measure toenail Hg levels by instrumental neutron-activation method. The Hg distribution was described with selected percentiles and geometric means. Multivariable linear regression (MLR) was used to examine potential determinants of Hg levels within ethnicity-gender subgroups. The geometric mean of toenail Hg was 0.212 (95 % CI = 0.207-0.218) μg/g. Hg levels varied geographically with Oakland the highest [0.381 (0.367-0.395) μg/g] and Minneapolis the lowest [0.140 (0.134-0.147) μg/g]. MLR analyses showed that male gender and AA ethnicity were negatively associated with toenail Hg levels, and that age, living in Oakland city, education level, alcohol consumption, and total fish intake were positively associated with toenail Hg concentrations within each ethnicity-gender subgroup. Current smokers were found to have higher Hg only in AA men. This study suggested age, gender, ethnicity, study center, alcohol, education level, and fish consumption consistently predict toenail Hg levels. As fish consumption was the key determinant, avoiding certain types of fish that have relatively high Hg levels may be crucial in reducing Hg intake.

Elevated blood lead levels and sources of exposure in the population of Kinshasa, the capital of the Democratic Republic of Congo

The objective of this study was to determine blood lead levels (BLLs) and the possible sources of exposure in the population of Kinshasa, the capital of the Democratic Republic of Congo. A cross-sectional survey was carried out from January to May 2008 in a representative sample of the Kinshasan population. BLL was measured in 275 individuals (53.4% women) aged 1-70 years in the urban area of Kinshasa and from 60 additional subjects in the rural area. Pb was also determined in environmental specimens (air and soil, indoor and outdoor). BLL in the study population ranged from 2.9 to 49.3 μg/dl (median, 9.9 μg/dl). The median BLL among children aged <6 years was 11.5 μg/dl (range: 3.0-37.8 μg/dl). Of these children, 71% had elevated BLL (≥10 μg/dl) and 22% had BLL ≥20 μg/dl. The proportion of elevated BLL (≥10 μg/dl) was higher for children aged <3 years than for children aged 3 to 5 years (97% vs 56%). A higher prevalence of elevated BLL was observed in urban compared with rural children (71% vs 20%). Significantly higher BLLs were also found in children whose mother consumed fired clay during pregnancy. Residential informal activities in the recycling of car batteries also contributed to elevated BLL in children. The elevated background of Pb exposure in the Kinshasan population indicates a public health issue that requires corrective actions. Pb-contaminated dust and air in children's home is an issue of public health concern. The use of leaded gasoline and the activities of car battery recycling in certain residences appear to constitute the main sources of exposure in the city of Kinshasa. The traditional use of fired clay for the treatment of gastritis by pregnant women is another significant contributor for elevated BLL in children.

Effect of lifestyles on the blood mercury level in Korean adults

Mercury (Hg) is widely distributed in the environment and oral exposure is a main route in the general population. In this study, we estimated the dietary intake of Hg and its relationship with blood Hg levels in Korean adults. The study subjects were recruited from three different districts (rural: 189, coastal: 208 and urban: 184). We used a general questionnaire to collect information about demographic factors, lifestyles and diet. Dietary habits were studied using the 24-h recall method. The estimation of Hg intake was performed using the database of Hg contents in 128 Korean foods based on the previous studies. Blood Hg was analyzed using Direct Mercury Analyzer with the gold-amalgam method. Daily intake of Hg by diet was estimated at 13.57 μg (0.22 μg/kg body weight). The geometric mean Hg concentration in whole blood was 3.92 μg/L. Blood Hg level and Hg intake by diet was higher in coastal areas than in urban or rural areas, respectively. Blood Hg level correlated with the intake of Hg consumed from diet. Seafood was highly responsible and account for 75.6% of total dietary Hg intake. In this study, blood Hg concentrations were found to be significantly affected by sex, age, individual lifestyles and especially the amount of seafood intake, which might play an important role in determining blood Hg levels in Korean adults.

Dietary mercury exposure in a population with a wide range of fish consumption--self-capture of fish and regional differences are important determinants of mercury in blood

Human, low level, chronic exposure to mercury (Hg) from fish is of concern because of potential neurodevelopmental and cardiovascular toxicity. The purpose of the study was to 1) measure total mercury (THg) in blood and estimate dietary exposure in a population group with a wide range of seafood consumption, 2) assess the intake and blood concentration in relation to tolerable intake values, 3) characterise dietary sources, and 4) to investigate the relationship between dietary THg with THg in blood (BTHg), including factors that can explain the variance in BTHg concentrations. The participants (n=184) filled in an extensive food frequency questionnaire which was combined with a database on THg concentrations in Norwegian food, and donated blood and urine. Median consumption of seafood was 65 g/day (range 4 to 341 g/day). The calculated mean dietary THg exposure was 0.35 (median 0.30) μg/kg body weight/week. Seafood contributed on average 95% to the exposure. The JECFA Provisional Tolerable Weekly Intake (PTWI) of 1.6 μg MeHg/kg bw/week was not exceeded by any of the participants. BTHg ranged from 0.6 to 30 μg/L, with a mean of 5.3 (median 4.0 μg/L). There was a strong relationship between total seafood consumption and BTHg concentrations (r=0.58 95%CI: 0.48, 0.67) and between estimated THg dietary exposure and BTHg (r=0.46 95%CI: 0.35, 0.57). Fish consumption, sex, catching >50% of their seafood themselves, and living in coastal municipalities were significant factors in linear regression models with lnBTHg. Including urinary Hg in the regression model increased the explained variance from 54% to 65%. In a toxicokinetic model, the calculated dietary intake appeared to moderately underestimate the measured BTHg among the participants with the highest BTHg. Only two of the participants had BTHg slightly above a value equivalent to the JECFA PTWI, but none of them were women in fertile age.

Heavy metal toxicity and the environment

Heavy metals are naturally occurring elements that have a high atomic weight and a density at least five times greater than that of water. Their multiple industrial, domestic, agricultural, medical, and technological applications have led to their wide distribution in the environment, raising concerns over their potential effects on human health and the environment. Their toxicity depends on several factors including the dose, route of exposure, and chemical species, as well as the age, gender, genetics, and nutritional status of exposed individuals. Because of their high degree of toxicity, arsenic, cadmium, chromium, lead, and mercury rank among the priority metals that are of public health significance. These metallic elements are considered systemic toxicants that are known to induce multiple organ damage, even at lower levels of exposure. They are also classified as human carcinogens (known or probable) according to the US Environmental Protection Agency and the International Agency for Research on Cancer. This review provides an analysis of their environmental occurrence, production and use, potential for human exposure, and molecular mechanisms of toxicity, genotoxicity, and carcinogenicity.

Urinary arsenic levels in the French adult population: the French National Nutrition and Health Study, 2006-2007

The French Nutrition and Health Survey (ENNS) was conducted to describe dietary intakes, nutritional status, physical activity, and levels of various biomarkers for environmental chemicals (heavy metals and pesticides) in the French population (adults aged 18-74 years and children aged 3-17 years living in continental France in 2006-2007). The aim of this paper was to describe the distributions of total arsenic and the sum of iAs+MMA+DMA in the general adult population, and to present their main risk factors. In the arsenic study, 1500 and 1515 adults (requested to avoid seafood intake in the previous 3 days preceding urine collection) were included respectively for the analysis of the sum of inorganic arsenic (iAs) and its two metabolites, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA), and for the total arsenic. Results were presented as geometric means and selected percentiles of urinary arsenic concentrations (μg/L) and creatinine-adjusted urinary arsenic (μg/g of creatinine) for total arsenic, and the sum of inorganic arsenic and metabolites (iAs+MMA+DMA). The geometric mean concentration of the sum of iAs+MMA+DMA in the adult population living in France was 3.34 μg/g of creatinine [3.23-3.45] (3.75 μg/L [3.61-3.90]) with a 95th percentile of 8.9 μg/g of creatinine (10.68 μg/L). The geometric mean concentration of total arsenic was 11.96 μg/g of creatinine [11.41-12.53] (13.42 μg/L [12.77-14.09]) with a 95th percentile of 61.29 μg/g of creatinine (72.75 μg/L). Urinary concentrations of total arsenic and iAS+MMA+DMA were influenced by sociodemographic and economic factors, and by risk factors such as consumption of seafood products and of wine. In our study, covariate-adjusted geometric means demonstrated several slight differences, due to consumption of fish, shellfish/crustaceans or wine. This study provides the first reference value for arsenic in a representative sample of the French population not particularly exposed to high levels of arsenic (10 μg/g of creatinine). It shows that urinary arsenic concentrations in the French adult population (in particular concentrations of iAs+MMA+DMA) were relatively low compared with foreign data.

Reference values for lead, cadmium and mercury in the blood of adults from the metropolitan area of Sao Paulo, Brazil

Human biomonitoring is an important tool for the evaluation of environmental exposure to contaminants. The data that are obtained from these studies might be compared to appropriate reference values (RVs) in a specific population. The RVs were derived from the rounded values of the upper limit of the 95th confidence interval of the 95th percentile for lead (Pb), cadmium (Cd) and mercury (Hg) in blood from adults in the metropolitan area of Sao Paulo (MASP), Brazil to investigate the association between blood metals and sociodemographic and lifestyle factors. Blood samples from 653 nonsmoking blood donors without occupational exposure to the studied metals were collected in 2006. Our evaluations distinguished a younger group (18-39 years) and an older group (40-65 years). RVs in the younger group were 60 μgPb/L and 4 μgHg/L for men and 47 μgPb/L and 4 μgHg/L for women. RVs in the older group were 80 μgPb/L and 5 μgHg/L for men and 63 μgPb/L and 6 μgHg/L for women. The RV for Cd was 0.6 μg/L for adults aged 18-65 years. Pb and Cd levels demonstrated a significant association with sex and age. Male blood contained 50% more Pb, and the older group exhibited 23% more Pb. Fish consumption and amalgam fillings were primarily related to Hg levels. RVs for lead were similar to the Czech Republic and Germany but higher than the US population. The RV for Cd in Brazil was well below the RVs of these countries. The RVs for Hg in Brazil were similar to the US but higher than Germany and the Czech Republic.

Persistent lipophilic environmental chemicals and endometriosis: the ENDO Study

BACKGROUND

An equivocal literature exists regarding the relation between persistent organochlorine pollutants (POPs) and endometriosis in women, with differences attributed to methodologies.

OBJECTIVES

We assessed the association between POPs and the odds of an endometriosis diagnosis and the consistency of findings by biological medium and study cohort.

METHODS

Using a matched cohort design, we assembled an operative cohort of women 18-44 years of age undergoing laparoscopy or laparotomy at 14 participating clinical centers from 2007 to 2009 and a population-based cohort matched on age and residence within a 50-mile catchment area of the clinical centers. Endometriosis was defined as visualized disease in the operative cohort and as diagnosed by magnetic resonance imaging in the population cohort. Logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for each POP in relation to an endometriosis diagnosis, with separate models run for each medium (omental fat in the operative cohort, serum in both cohorts) and cohort. Adjusted models included age, body mass index, breast-feeding conditional on parity, cotinine, and lipids.

RESULTS

Concentrations were higher in omental fat than in serum for all POPs. In the operative cohort, γ-hexachlorocyclohexane (γ-HCH) was the only POP with a significant positive association with endometriosis [per 1-SD increase in log-transformed γ-HCH: adjusted OR (AOR) = 1.27; 95% CI: 1.01, 1.59]; β-HCH was the only significant predictor in the population cohort (per 1-SD increase in log-transformed β-HCH: AOR = 1.72; 95% CI: 1.09, 2.72).

CONCLUSIONS

Using a matched cohort design, we found that cohort-specific and biological-medium-specific POPs were associated with endometriosis, underscoring the importance of methodological considerations when interpreting findings.

Distribution of blood concentrations of persistent organic pollutants in a representative sample of the population of Barcelona in 2006, and comparison with levels in 2002

INTRODUCTION

POP biomonitoring programs are useful for exposure assessment, to analyze patterns, and to evaluate policies. However, population-representative surveys are scarce and heterogeneous. Reports on time trends in representative samples using the same methods are rare.

OBJECTIVES

To analyze the distribution of serum concentrations of 19 POPs in the general population of Barcelona city in 2006, and to compare it with the distribution in 2002.

METHODS

231 participants in the Barcelona Health Survey were interviewed face-to-face, gave blood, and underwent a physical exam. Density plots ("POP Geoffrey Rose curves") were used to represent the full population distribution of each compound.

RESULTS

Eight POPs were each detected in >80% of the study subjects: p,p'-DDT, p,p'-DDE, PCB congeners 118, 138, 153 and 180, HCB and β-HCH. The minimum number of POPs detected in one person was 5, and 72% of the population accumulated ≥ 10 compounds. p,p'-DDE and HCB showed the highest concentrations (median=219 and 109 ng/g lipid, respectively). Concentrations decreased by 34-56% from 2002 to 2006. The decrease was similar in women and men, and in all age groups/birth cohorts. It was larger with increasing BMI; for p,p'-DDT, HCB and β-HCH the decrease in obese individuals was 31-44 percentage points larger than in subjects with normal weight. The distribution of POP concentrations was always switched towards higher values in women than men. POP levels also differed significantly by age, body mass index, weight gain, birth place and social class, but not by parity and breastfeeding. The two younger cohorts had a higher DDT/DDE ratio than the oldest cohort.

CONCLUSION

Although human POP contamination remains common in the city of Barcelona, concentrations decreased significantly in 4years. Our approach suggests innovative ways to conceive, analyze and present results for other monitoring programs.

Renal function after reduction in cadmium exposure: an 8-year follow-up of residents in cadmium-polluted areas

BACKGROUND AND OBJECTIVE

Long-term exposure to cadmium (Cd) causes renal dysfunction, but the change in renal function with exposure is unknown. We assessed the evolution of Cd-induced renal effects after a reduction in dietary exposure to Cd in rice.

METHODS

Four hundred twelve residents in previously Cd-polluted and nonpolluted areas were examined twice, in 1998 and in 2006. Changes in blood Cd, urinary Cd, and kidney function [N-acetyl-β-d-glucosaminidase (NAG), β2-microglobulin, and albumin in urine] were measured.

RESULTS

In the most polluted area, mean blood Cd was 8.9 μg/L and 3.3 μg/L in 1998 and in 2006, respectively, and urinary Cd was 11.6 and 9.0 μg/g creatinine. Urinary albumin in 1998 increased with urinary Cd, but no such exposure-response relation appeared for 2006 albumin versus urinary Cd 1998, indicating recovery. Other biomarkers of kidney function were also elevated in 1998. Partial recovery was observed for NAG among women and was suggested for β2-microglobulin among young individuals. The probability of having β2-microglobulin levels above the 95th percentile in 2006 was high in those with elevated β2-microglobulin in 1998 [odds ratio (OR) = 24.8; 95% confidence interval (CI): 11.2, 55.3] compared with albumin (OR = 3.0; 95% CI: 1.2, 7.5) and NAG (OR = 2.6; 95% CI: 1.6, 4.4).

CONCLUSIONS

Results suggest that a Cd-mediated increase in urinary albumin excretion is reversible upon substantial reduction of exposure. For markers of tubular effects, we observed a tendency toward improvement but not complete recovery. Data from repeated observations suggest that β2-microglobulin may be more informative than NAG as an indicator for an individual's future tubular function.

Plasma polychlorinated biphenyls (PCB) levels of workers in a transformer recycling company, their family members, and employees of surrounding companies

In spring 2010, high internal exposures (up to 236 μg/L plasma) for the sum of indicator polychlorinated biphenyls (PCB) were discovered in workers in a transformer recycling company in Germany, where PCB-contaminated material was not handled according to proper occupational hygiene. The release of PCB from this company raised growing concerns regarding possible adverse human health effects correlated with this exposure. This provided a basis for a large biological monitoring study in order to examine the internal exposure to PCB in individuals working in that recycling company, their family members, and relatives, as well as subjects working or living in the surroundings of this company. Blood samples from 116 individuals (formerly) employed in the transformer recycling company and 45 direct relatives of these persons were obtained. Further, blood samples of 190 subjects working in close vicinity of the recycling plant, 277 persons working in the larger area, and 41 residents of the area were investigated. Plasma samples were analyzed for the 6 indicator PCB (PCB 28, 52, 101, 138, 153, 180) and 12 dioxin-like PCB using gas chromatography/mass spectroscopy (GC/MS; limit of detection [LOD] at 0.01 μg/L). Median concentrations (maximum) for the sum of the 6 indicator PCB in blood of the employees, their relatives, individuals working in close vicinity, persons working in the larger area, and the residents were 3.68 (236.3), 1.86 (22.8), 1.34 (22.9), 1.19 (6.42), and 0.85 (7.22) μg/L plasma, respectively. The (former) employees of the transformer recycling plant partly showed the highest plasma PCB levels determined thus far in Germany. Even family members displayed highly elevated levels of PCB in blood due to contaminations of their homes by laundering of contaminated clothes. Vicinity to the recycling plant including reported contact with possibly contaminated scrap was the main contributor to the PCB levels of the workers of the surrounding companies. Residents of the area did not show significantly elevated blood PCB levels compared to the general population. Our biomonitoring results served as a basis for individual risk communication and successful risk management.