Trends In Blood Lead Levels Research Articles

Trends of Blood Lead Levels in US Pregnant Women: The National Health and Nutrition Examination Survey (2001-2018).

ObjectivesThis study investigates the trends of blood lead levels in US pregnant women based on the National Health and Nutrition Examination Survey from 2001 to 2018.MethodsA total of 1,230 pregnant women were included in this study. The weighted logistic regression was applied to analyze the association between sociodemographic characteristics with high blood levels. We computed the blood lead levels for each survey period from 2001–2002 to 2017–2018. Moreover, we used the adjusted linear regression model to investigate the time-related change in blood lead level. The odds ratio (OR) with a 95% confidence interval (CI) was calculated accordingly.ResultsThe mean blood lead was 0.73 ± 0.03 ug/dL, and high blood lead was observed in 2.53% of individuals. The Mexican Americans were more associated with high blood lead than the non-Hispanic white (OR, 1.072; 95% CI, 1.032-1.112). The mean blood lead level has decreased from 0.97 ug/dL in 2001–2002 to 0.46 ug/dL in 2013–2014. Afterward, a slight increase was observed with the mean blood lead of 0.55 ug/dL in 2015–2016 and 0.53 ug/dL in 2017-2018. In the adjusted linear regression model, each year's increase would lead to a 0.029 ug/dL decrease in blood lead (P < 0.001). However, no significant change was observed in the 2017–2018 cycle compared with 2009–2010 (P = 0.218).ConclusionThis study summarized the trend of blood lead levels in US pregnant women over 2001–2018. Continued effort is still required to control lead sources better and protect this population from lead exposure.

Trend in blood lead levels in Taiwanese adults 2005-2017.

This study examined the trend of blood lead levels (BLLs) in Taiwanese adults and analyzed the variations in the BLL between Linkou (northern) and Kaohsiung (southern) hospital branches. Between 2005 and 2017, 3,804 adult participants received blood lead tests at the Linkou (n = 2,674) and Kaohsiung (n = 1,130) branches of Chang Gung Memorial Hospital. The geometric mean of BLL was 2.77 μg/dL. The adult participants from the Kaohsiung branch were not only age older (49.8±14.1 versus 39.4±14.2 years; P<0.001) and male predominant (65.8 versus 41.7%; P<0.001) but also showed a higher BLL (4.45±3.93 versus 2.82±2.42 μg/dL; P<0.001) and lower estimated glomerular filtration rate (87.62±25.94 versus 93.67±23.88; P<0.001) than those from the Linkou branch. Multivariable logistic regression analysis revealed that the Kaohsiung branch [odds ratio (OR): 7.143; 95% confident interval (CI): 5.682-8.929; P<0.001], older age (OR: 1.008; 95% CI: 1.000-1.015; P = 0.043) and reduced estimated glomerular filtration rate (OR: 1.009; 95% CI: 1.004-1.014; P = 0.001) were significant predictors for BLL > 5 μg/dL. Therefore, this study confirmed a continuous decreasing trend in the BLL in Taiwan after banning leaded petrol in 2000.

Trends in Blood Lead Levels in the U.S. From 1999 to 2016

Trends in blood lead levels in the same birth cohort (generation) are necessary to identify the lead load in the population. This analysis uses a nationally representative sample to investigate the trends in blood lead levels from 1999 to 2016 by birth cohort and to revisit the association between blood lead levels and age. Data from the 1996 to 2016 National Health and Nutrition Examination Surveys were used to describe the distribution of blood lead levels. Trends in blood lead levels were analyzed using joinpoint regression models. Association of blood lead levels with age was conducted with both cross-sectional and birth cohort analysis. Analyses were conducted in 2020. In total, 68,877 participants were included (weighted mean age=38.4 years, 50.6% female). From 1999 to 2016, the geometric mean of blood lead levels decreased from 1.68 µg/dL (95% CI=1.63, 1.74) to 0.82 µg/dL (95% CI=0.77, 0.87). The annual percentage change estimated by the joinpoint model was -4.26% (p<0.05). The associations between blood lead levels and age were "U"-shaped by cross-sectional analysis, with higher risks for the lowest and highest ages. However, by birth cohort analysis the blood lead levels declined monotonically with age. The joinpoint analysis indicated the inflection point of age 13-17 years and statistically significant differences in decline slopes before and after this age. In this nationally representative study of the U.S. population, estimates of blood lead levels showed an overall decrease from 1999 to 2016. Blood lead levels are highest in childhood.

Long-term time trend of lead exposure in young German adults - Evaluation of more than 35Years of data of the German Environmental Specimen Bank.

Lead is a ubiquitous pollutant with well-known effects on human health. As there is no lower toxicological threshold for lead in blood and since data gaps on lead exposure still exist in many European countries, HBM data on lead is of high importance. To address this, the European Human Biomonitoring Initiative HBM4EU classified lead as a priority substance. The German Environmental Specimen Bank (German ESB) has monitored lead exposure since more than 35 years. Using data from the early 1980s to 2019 we reveal and discuss long-term trends in blood lead levels (BLLs) and current internal exposure of young adults in Germany. BLLs in young adults decreased substantially in the investigated period. As results from the ESB sampling site Muenster demonstrate, the geometric mean of BLLs of young adults decreased from 1981 (78,7μg/L) to 2019 (10.4μg/L) by about 87%. Trends in human exposure closely correlate with air lead levels (ALLs) provided by the European Monitoring and Evaluation Programme (EMEP). Hence, the decrease of BLLs largely reflects the drop in air lead pollution. Known associations of sex, smoking, alcohol consumption, and housing situation with BLLs are confirmed with data of the German ESB. Although internal lead exposure in Germany decreased substantially, the situation might be different in other European countries. Since 2010, BLLs of young adults in Germany levelled out at approximately 10μg/L. The toxicity of lead even at low levels is known to cause adverse health effects especially in children following exposure of the child or the mother during pregnancy. To identify current exposure sources and to minimize future lead exposure, continuous monitoring of lead intake and exposure levels is needed.

The Epidemiology of Lead Poisoning Notifications in New South Wales, Australia, 1996-2016

Background/Aim: Elevated blood lead levels have been notifiable in New South Wales (NSW), Australia since 1996. In that time the notifiable blood lead level has been reduced twice, from 15µg/dL to 10µg/dL in 2012 and to 5µg/dL in 2016. We evaluated the impact of this change on notification rates in NSW, and assessed the characteristics and quality of surveillance data. Methods: We analysed notification data for 1996-2016 by geographical area, age, sex, exposure status and occupation, and described trends in blood lead levels. We calculated notification rates and compared these over time and between geographic regions. We also described the characteristics of the surveillance dataset and made recommendations for improvement. We used Stata version 14.1 for all analyses. Results: There were 9724 notifications between 1996–2016, with an average annual notification rate of 6.8 per 100,000. In 2016 the notification rate of 12.9 per 100,000 was double the average rate for the preceding five years. When only notifications of blood lead levels above 15µg/dL were considered, the notification rate for 2016 was 1.94 per 100,000, the lowest rate during the 21-year study period. Notification rates in rural regions where lead mining has occurred, and where there is systematic screening, were more than 10 times higher than in other regions. Key limitations of the data included the lack of a single comprehensive data source, high rates of missing data, and the presence of free-text responses. These limitations made it difficult to analyse notifications rates, particularly by risk and exposure history. Conclusions: Changes to the case definition increased notification rates of elevated blood lead, however when considering only notifications above 15µg/dL rates are at their lowest since lead poisoning became notifiable. It is important to improve data completeness in the lead surveillance system to enhance understanding of the epidemiology of elevated blood lead levels in NSW and factors which lead to increased risk.

Longitudinal trends of blood lead levels before and after leaded gasoline regulation in Korea.

The objective of this study was to verify a change in the longitudinal trend of blood lead levels for the Korean population, before and after the regulation of leaded gasoline— which occurred between 1987 and 1993 in Korea. A total of 77 reports on blood lead levels among general Korean population between 1981 and 2014 were selected, and the results were summarized to have the variables of year, number of subjects, the subjects’ range in age, gender, and blood lead concentrations (arithmetic mean). The annual average atmospheric lead levels for four major cities (i.e., Seoul, Busan, Daegu and Gwangju) were collected from the Air Pollution Monitoring Database from 1991, and pilot studies from 1985 to 1990 before the national air quality monitoring system was launched in 1991. Blood lead levels were visualized in a bubble plot in which the size of each bubble represented the sample size of each study, and the annual average concentrations in ambient air were depicted on line graphs. Blood lead levels in the Korean population tended to gradually increase from the early 1980s (approximately 15-20 μg/dL) until 1990-1992 (20-25 μg/dL). Blood lead levels then began to rapidly decrease until 2014 (<2 μg/dL). Similar patterns were observed for both adults (≥20 years) and younger children/adolescents. The same longitudinal trend was observed in annual average atmospheric lead concentration, which suggests a significant correlation between air lead concentration and blood lead concentration in the general population. In conclusion, the regulation of leaded gasoline has significantly contributed to the rapid change in blood lead concentrations. And, the regulation of other sources of lead exposure should be considered to further decrease blood lead levels in the Korean population.

In Memoriam: Herbert L. Needleman

In Memoriam: Herbert L. Needleman

Blood Lead Levels in Young Children: US, 2009-2015

To evaluate trends in blood lead levels in children <6years of age, this Quest Diagnostics Health Trends report builds on previously reported National Health and Nutrition Examination Survey data with a much larger national group and adds more detail and novel assessments. This report describes the results from a 6-year retrospective study (May 2009-April 2015) based on >5 million blood lead level results (including >3.8 million venous results) from children <6years old living in all 50 states and the District of Columbia. We evaluated yearly changes and examined demographic categories including sex, pre-1950s housing construction, poverty income ratios (PIRs), Medicaid enrollment status, and geographic regions. Among children <6years old, 3.0% exhibited blood lead levels ≥5.0μg/dL (high). There were significant differences in high blood lead levels based on sex, pre-1950s housing construction quintiles, and PIR<1.25 and PIR>5 (all P<.01). Health and Human Services regions, states, and 3-digit ZIP code areas exhibited drastically different frequencies of high blood lead levels and blood lead levels ≥10.0μg/dL (very high). Generally, levels declined over time for all groups. Examination of more than 5 million venous blood lead level results in children younger than 6years old allowed for a robust, detailed analysis of blood lead level group results by geography and other criteria that are prohibited with the narrower National Health and Nutrition Examination Survey database. Progress in reducing the burden of lead toxicity is a public health success story that is incomplete with some identified factors posing larger, ongoing challenges.

Trends and variability in blood lead concentrations among US adults aged 20-64years and senior citizens aged ≥65years.

Using data from National Health and Nutrition Examination Survey for the period 2003-2012, the objective of this study was to evaluate trends in blood lead levels (BLL) among adults aged 20-64years (adults) and seniors aged ≥65years (seniors). In addition, the contribution of other factors like gender, race/ethnicity, smoking, and exposure to secondhand smoke at home in explaining variability in BLL was also evaluated by fitting regression models with log10 transformed values of BLL as dependent variables. BLL decreased over 2003-2012 (p < 0.01). Irrespective of gender, race/ethnicity, and smoking status, seniors were found to have higher BLL than adults. Based on the magnitude of differences between the 5th and 95th percentiles, variability in the levels of blood lead was found to be substantially higher among seniors than among adults. Males had statistically significantly higher adjusted BLL than females (2.32 vs. 1.76μg/dL for seniors, p < 0.01 and 1.66 vs. 1.13μg/dL for adults, p < 0.01). Non-Hispanic whites had statistically significantly lower adjusted BLL than non-Hispanic blacks (1.99 vs. 2.42μg/dL for seniors, p < 0.01 and 1.22 vs. 1.42μg/dL for adults, p < 0.01). When compared with non-smokers, smokers had statistically significantly higher BLL (2.19 vs. 1.86μg/dL for seniors, p < 0.01 and 1.54 vs. 1.22μg/dL for adults, p < 0.01). Non-obese had statistically significantly higher BLL than obese individuals (2.11 vs. 1.93μg/dL for seniors, p < 0.01 and 1.48 vs. 1.27μg/dL for adults, p < 0.01). Exposure to secondhand smoke at home (SHS) was associated with statistically significantly higher BLL than when there was no exposure to SHS (β = 0.0683, p = 0.03 for seniors; β = 0.034, p = 0.034, p < 0.01 for adults).

Trends and variability in blood lead concentrations among US children and adolescents.

Using data from the National Health and Nutrition Examination Survey for the period 2003-2012, the objective of this study was to evaluate trends in blood lead levels (BLL) among children aged 1-5and 6-11years and smoker and nonsmoker adolescents aged 12-19years. Regression models with log10 transformed values of BLLs as dependent variable were fitted to evaluate how gender, race/ethnicity, smoking, and exposure to secondhand smoke at home affect BLLs. Irrespective of age, gender, and race/ethnicity, BLLs declined over the study period (p ≤ 0.01). Overall, adjusted BLLs declined by 0.00114μg/dL for every 2years. Children aged 1-5years had about 50% higher BLLs than smoker adolescents, about 75% higher BLLs than nonsmoker adolescents, and about 45% higher BLLs than children aged 6-11years. While overall, children aged 1-5years with BLL ≥ 5μg/dL made up 3.24%, 7.8% non-Hispanic Black children aged 1-5years had BLL ≥ 5μg/dL. Males were found to have higher adjusted BLLs than females, and non-Hispanic Blacks were found to have higher adjusted BLLs than non-Hispanic Whites. Higher poverty income ratio was associated with lower adjusted BLLs (β = -0.02916, p < 0.01). Children living in owner-occupied homes had lower adjusted BLLs than children living in renter-occupied homes. BLLs increased with increase in number of smokers smoking inside the home (β = 0.02496, p = 0.02). In conclusion, while BLLs have declined for all age groups, genders, and races/ethnicities, certain races/ethnicities like non-Hispanic Blacks continue to have substantially higher BLLs than non-Hispanic Whites.

Blood lead levels of Korean lead workers in 2003-2011.

ObjectivesThis study aimed to document the trend in blood lead levels in Korean lead workers from 2003 until 2011 and blood lead levels within each of the main industries.MethodsNine years (2003–2011) of blood lead level data measured during a special health examination of Korean lead workers and collected by the Korea Occupational Safety and Health Agency were analyzed. Blood lead levels were determined by year, and a geometric mean (GM) was calculated for each industry division.ResultsThe overall GM blood lead level for all years combined (n = 365,331) was 4.35 μg/dL. The GM blood lead level decreased from 5.89 μg/dL in 2003 to 3.53 μg/dL in 2011. The proportion of the results ≥30 μg/dL decreased from 4.3% in 2003 to 0.8% in 2011. In the “Manufacture of Electrical Equipment” division, the GM blood lead level was 7.80 μg/dL, which was the highest among the industry divisions. The GM blood lead levels were 7.35 μg/dL and 6.77 μg/dL in the “Manufacturers of Rubber and Plastic Products” and the “Manufacture of Basic Metal Products” division, respectively.ConclusionsThe blood lead levels in Korean lead workers decreased from 2003 to 2011 and were similar to those in the US and UK. Moreover, workers in industries conventionally considered to have a high risk of lead exposure also tended to have relatively high blood lead levels compared to those in other industries.

Trends in Tobacco Smoke Exposure and Blood Lead Levels Among Youths and Adults in the United States: The National Health and Nutrition Examination Survey, 1999–2008

IntroductionTobacco smoke is a source of exposure to thousands of toxic chemicals including lead, a chemical of longstanding public health concern. We assessed trends in blood lead levels in youths and adults with cotinine-verified tobacco smoke exposure by using 10 years of data from the National Health and Nutrition Examination Survey.MethodsGeometric mean levels of blood lead are presented for increasing levels of tobacco smoke exposure. Regression models for lead included age, race/ethnicity, poverty, survey year, sex, age of home, birth country, and, for adults, alcohol consumption. Lead levels were evaluated for smokers and nonsmokers on the basis of age of residence and occupation.ResultsPositive trend tests indicate that a linear relationship exists between smoke exposure and blood lead levels in youths and adults and that secondhand smoke exposure contributes to blood lead levels above the level caused by smoking.ConclusionYouths with secondhand smoke exposure had blood lead levels suggestive of the potential for adverse cognitive outcomes. Despite remediation efforts in housing and the environment and declining smoking rates and secondhand smoke exposure in the United States, tobacco smoke continues to be a substantial source of exposure to lead in vulnerable populations and the population in general.

Environmental Lead: Rabito et al. Respond

We thank Mielke for his interest in our study of residential lead hazards in New Orleans (Rabito et al. 2012). In our study we found that most homes had either dust or soil lead above federal standards and concluded that children are at risk for lead exposure. Regarding the specific issue of whether soil lead has increased or decreased, we agree that a direct comparison between census-level soil lead survey data and direct measure-ments of residential samples has limitations. To reiterate the limitations outlined in our article (Rabito et al. 2012), differences in the number of soil samples, the sampling methodology, and the sample location limited our ability to directly measure any change in soil lead levels. Although it is of interest to know whether soil lead has increased or decreased as a result of Hurricane Katrina, our focus was to measure current residential lead hazards, because lead contamination in and around homes is the primary pathway of exposure for children (Lanphear and Roghmann 1997). Our finding that 61% of homes had lead levels above federal standards provides evidence that New Orleans children are at high risk of exposure. That the samples were collected from homes typically considered to be low risk (given the socio-demographic characteristics of the sample) is cause for added concern. In his letter, Mielke refers to trends in blood lead levels. The issue of whether blood lead levels are increasing or decreasing in New Orleans children—which was not within the scope of our study (Rabito et al. 2012)—is not easily addressed using surveillance data. Screening practices and rates drive the reported prevalence in any given year. Zahran et al. (2010) compared aggregate blood lead levels derived from the Louisiana Childhood Blood Lead Surveillance System (CBLSS) pre-Hurricane Katrina to levels post-Hurricane Katrina and found that median blood lead had decreased. However, profound changes in the socio-demographic makeup of the New Orleans population make the comparison vulnerable to significant bias (Bloomberg 2011). The surveillance data provided by Mielke supports our notion that the post-Hurricane Katrina population screened under the CBLSS is not stable from year to year. As stated by Mielke, 6.4% of children had elevated blood lead levels in 2008, but the estimate decreased to 3.3% in 2010. This decrease might not be valid because the majority of children in the 2008 cohort were from the inner city (with the highest prevalence of old housing) whereas the 2010 cohort included a higher proportion from outer areas of the city (considered low risk based on housing age). The assumption by Zahran et al. (2010) that soil lead serves as a proxy for length of lead exposure is likely not valid given the amount of housing destabilization and subsequent mobility of the population in the years following the storm. Finally, low screening rates, coupled with a reporting level of > 10 µg/dL (widely accepted as above the level of concern) does not allow for the valid estimation of the preva-lence of elevated blood lead levels in New Orleans children. Regardless of the inconclusive nature of blood lead data, given that 61% of sampled homes have significant lead hazards, we maintain that New Orleans children who live in old housing are at risk for lead exposure independent of race or income. We support the recent statement by the Centers for Disease Control and Prevention Advisory Committee on Childhood Lead Poisoning Prevention that “the goal of primary prevention is to ensure that all homes become lead-safe and do not contribute to childhood lead exposure” (Centers for Disease Control and Prevention 2012). The City of New Orleans has made strides in its fight to reduce lead hazards in public places; however, they should not relax in their efforts to protect the environ-ment from further contamination.

Primary Prevention of Lead Exposure—Blood Lead Results at Age Two Years

Objectives: The Philadelphia Lead Safe Homes (LSH) Study was designed to evaluate whether educational and environmental interventions in the first year of life for families of newborns increased knowledge of lead exposure prevention and were associated with less elevation of blood lead levels (BLLs) for these children, when compared to children receiving standard care. Methods: The current study performed descriptive statistics on the second-year BLL data for both groups and compared these using chi-square tests for proportions and unpaired t-tests for means. Results: A BLL result was found for 159 (50.6%) of the 314 LSH cohort children and 331 (52.7%) of the 628 control children (p = 0.1). Mean and standard deviation for age at draw was 23.8 (3.4) months versus 23.6 (3.1) months (P = 0.6). Geometric mean BLLs were 3.7 versus 3.5 µg/dL (P = 0.4). The percentages of the cohort group with a BLL of ≥20, ≥10 and ≥5 μg/dL, respectively, were 0.6%, 5% and 30%; for the controls 1.2%, 6.6%, and 25%. These percentages were not significantly different between groups. Conclusion: A comparison of geometric mean BLLs and percentages above several BLL cut points drawn at age two years in a group of urban newborns benefitting from study interventions versus a group of similar urban children did not yield statistically significant differences. Both groups had relatively lower lead levels when compared to historical cohort groups, which may reflect a continuing downward trend in BLLs in U.S. children. The interventions did result in benefits to the families such as an increase in parental knowledge about lead exposure prevention and in-home wet cleaning activity, and a decrease in lead dust levels in study homes.

Unleaded gasoline use and lead level change in human blood

Rapid economic development and industrialization has been accompanied by an increase of energy consumption and environmental pollution. The consumption of gasoline has increased in general. However, the use of leaded gasoline has continuously decreased since 1988 in Korea. The Health Surveillance Project was launched in Korea in 1980, which questioned symptoms based on questionnaires and medical examinations from residents in the vicinity of 13 industrial areas and 2 non-industrial areas. 10,598 persons living in these 15 areas had medical checkups and donated their blood for heavy metal analysis from 1980 to 2000 through this project. Especially, the lead levels in participants’ blood of these areas were determined and monitored. Finally 4,967 samples in target areas were used to review the trend of lead level in blood in this paper. Ranges of lead concentrations by areas were from 15.2 to 21.0 μg/dL in 1981 and 22.3 to 34.3 μg/dL in 1988, but were 8.8 to 11.1 μg/dL in 1992 and 4.4 to 4.8 μg/dL in 1995. The consumption of leaded gasoline was at a peak in 1988. Blood lead level showed a very close relationship with the consumption rate of leaded gasoline in the change pattern (p<0.01) and showed a clear declining trend since the use of unleaded gasoline, especially from 1988, the year of Seoul Olympic game (ex, the blood lead levels were 15.2 μg/dL in 1981, 20.2 μg/dL in 1985, 24.3 μg/dL in 1988 and 3.9 μg/dL in 1993 in Yochon area). China also showed an decreasing trend of blood lead levels of the general population since the end of 1990s, when lead free gasoline was provided to China.

Trends in blood lead levels in UK workers, 1995–2007

ObjectivesThis study evaluated blood lead data (including zinc protoporphyrin (ZPP) and haemoglobin levels) collected at the UK's Health and Safety Laboratory (HSL) in order to determine temporal changes in occupational...

Trends in Blood Lead Levels and Blood Lead Testing Among US Children Aged 1 to 5 Years, 1988–2004

To evaluate trends in children's blood lead levels and the extent of blood lead testing of children at risk for lead poisoning from national surveys conducted during a 16-year period in the United States. Data for children aged 1 to 5 years from the National Health and Nutrition Examination Survey III Phase I, 1988-1991, and Phase II, 1991-1994 were compared to data from the survey period 1999-2004. The prevalence of elevated blood lead levels, >/=10 microg/dL, among children decreased from 8.6% in 1988-1991 to 1.4% in 1999-2004, which is an 84% decline. From 1988-1991 and 1999-2004, children's geometric mean blood lead levels declined in non-Hispanic black (5.2-2.8 microg/dL), Mexican American (3.9-1.9 microg/dL), and non-Hispanic white children (3.1 microg/dL to 1.7 microg/dL). However, levels continue to be highest among non-Hispanic black children relative to Mexican American and non-Hispanic white children. Blood lead levels were distributed as follows: 14.0% were <1.0 microg/dL, 55.0% were 1.0 to <2.5 microg/dL, 23.6% were 2.5 to <5 microg/dL, 4.5% were 5 to <7.5 microg/dL, 1.5% were 7.5 to <10 microg/dL, and 1.4% were >/=10 microg/dL. Multivariable analysis indicated that residence in older housing, poverty, age, and being non-Hispanic black are still major risk factors for higher lead levels. Blood lead testing of Medicaid-enrolled children increased to 41.9% from 19.2% in 1988-1991. Only 43.0% of children with elevated blood lead levels had previously been tested. Children's blood lead levels continue to decline in the United States, even in historically high-risk groups for lead poisoning. To maintain progress made and eliminate remaining disparities, efforts must continue to test children at high risk for lead poisoning, and identify and control sources of lead. Coordinated prevention strategies at national, state, and local levels will help achieve the goal of elimination of elevated blood lead levels.

Blood lead and cadmium levels and relevant factors among children from an e-waste recycling town in China

Background Primitive electronic waste (e-waste) recycling is ongoing in Guiyu, and thus toxic heavy metals may keep on threatening to the health of local children. Some related factors may contribute to the elevation of blood lead levels (BLLs) or blood cadmium levels (BCLs). Objective To investigate the children's BLLs and BCLs in Guiyu and Chendian as compare to discuss the effects of primitive e-waste recycling activities on children's health. Methods Two hundred and seventy-eight children less than 8 years who lived in Guiyu and Chendian were observed, and their BLLs and BCLs were determined by graphite atomizer absorption spectrophotometer. Questionnaire survey for risk factors was also performed and data were analyzed using spearman correlation analyses and logistic regression analyses. Results Children living in Guiyu had significantly higher BLLs and BCLs as compared with those living in Chendian ( p<0.01). In Guiyu, 70.8% of children (109/154) had BLLs>10 μg/dL, and 20.1% of children (31/154) had BCLs>2 μg/L, compared with 38.7% of children (48/124) had BLLs>10 μg/dL and 7.3% of children (9/124) had BCLs>2 μg/L in Chendian ( p<0.01, respectively). We also observed a significant increasing trend in BLLs with increasing age in Guiyu ( p<0.01). Mean height of children in Guiyu was significantly lower than that in Chendian ( p<0.01). The risk factors related to children's BLLs and BCLs mainly included father's engagement in the work related to e-waste, children's residence in Guiyu and the amount of time that children played outside near the road everyday. Conclusions There are close relationships between the BLLs, BCLs in children and the primitive e-waste recycling activities in Guiyu. Environmental pollution, especially lead pollution, has threatened the health of children living around e-waste recycling site.

Elevated Blood Lead Levels of Children in Guiyu, an Electronic Waste Recycling Town in China

BackgroundElectronic waste (e-waste) recycling has remained primitive in Guiyu, China, and thus may contribute to the elevation of blood lead levels (BLLs) in children living in the local environment.ObjectivesWe compared the BLLs in children living in the e-waste recycling town of Guiyu with those living in the neighboring town of Chendian.MethodsWe observed the processing of e-waste recycling in Guiyu and studied BLLs in a cluster sample of 226 children < 6 years of age who lived in Guiyu and Chendian. BLLs were determined with atomic absorption spectrophotometry. Hemoglobin (Hgb) and physical indexes (height and weight, head and chest circumferences) were also measured.ResultsBLLs in 165 children of Guiyu ranged from 4.40 to 32.67 μg/dL with a mean of 15.3 μg/dL, whereas BLLs in 61 children of Chendian were from 4.09 to 23.10 μg/dL with a mean of 9.94 μg/dL. Statistical analyses showed that children living in Guiyu had significantly higher BLLs compared with those living in Chendian (p < 0.01). Of children in Guiyu, 81.8% (135 of 165) had BLLs > 10 μg/dL, compared with 37.7% of children (23 of 61) in Chendian (p < 0.01). In addition, we observed a significant increasing trend in BLLs with increasing age in Guiyu (p < 0.01). It appeared that there was correlation between the BLLs in children and numbers of e-waste workshops. However, no significant difference in Hgb level or physical indexes was found between the two towns.ConclusionsThe primitive e-waste recycling activities may contribute to the elevated BLLs in children living in Guiyu.

Human biomonitoring system in the Czech Republic

The human biomonitoring (HBM) is an integral part of Environmental Health Monitoring System in the Czech Republic since 1994. Selected biomarkers of the internal dose (heavy metals, PCBs) and cytogenetic analysis of peripheral lymphocytes as a biomarker of the exposure/effect to/of environmental genotoxic factors are systematically followed up in the blood and urine of adults (blood donors), in children aged 8 to 10 years, and in the breast milk of nursing mothers. Selected outputs documented the declining trend of blood lead levels, with the recent reference value of 80 mg/l for men, and the rising trend of blood selenium levels in adults, but not in children. PCBs and chlorinated pesticides in human milk show a long-term downward trend, but still higher than in neighbouring countries. The frequency of aberrant cells revealed a downward trend, but the increase obtained in the last monitored period needs to be explained. Further HBM activities are required to demonstrate the corresponding trends and to reduce human exposure and health risks.