Prevalence Of Elevated Blood Lead Levels Research Articles

Evaluating Housing Characteristics Associated With Childhood Lead Exposure in Providence, Rhode Island.

This research aims to take an in-depth look into the child, housing, and neighborhood characteristics associated with Providence children's likelihood of having elevated blood lead levels (BLLs). The 2019 Providence, Rhode Island, Property Tax Assessor's database, containing each property owner's address, was geocoded and spatially joined with the 2017-2019 blood lead tests for children aged 0 to 6 years from the Rhode Island Department of Health. The prevalence of elevated BLLs (≥5 μg/dL) overall, as well as by property type, number of properties owned, owner occupancy, assessed value, and neighborhood rates of old housing and poverty, was computed. We assessed the relationship between having elevated BLLs and these housing and neighborhood characteristics, adjusting for gender, age at test, and test method. We found that, compared with children living in properties with landlords who owned only one property, children living in properties with landlords who owned 4 or more properties had lower odds of having elevated BLLs (odds ratio = 0.98; 95% confidence interval, 0.97-0.99). The proportion of houses built pre-1950 in the neighborhood was associated with increased odds of elevated BLLs. There was no significant association between owner-occupancy status and property type with children having elevated BLLs. Children living in properties with landlords who owned 4 or more properties were less likely to have elevated BLLs. This association may suggest that the current lead legislation is having some impact, but public health efforts should address lead exposure in properties that are currently exempt from the law.

Follow-up of Elevated Blood Lead Levels and Sources in Children at One and Six Years of Age in Benin: A Cohort Study

Background/Aim: Lead has detrimental health effects on children including reduced cognitive and behavioural development. A high prevalence (58%) of elevated Blood Lead Levels (BLLs) (>50 µg/L) was observed in 685 one-year-old infants in semi-rural Benin in 2011-13. These children were reassessed in 2016-18 to assess sources of exposure and reductions in BLLs. Methods: BLLs were analyzed by inductively coupled plasma mass spectrometry (n=425). Sources were assessed through a questionnaire. BLLs and prevalence of elevated BLLs at six years of age are described and compared to BLLs measured in 2011-13. Multivariate linear and quantile regressions were conducted to determine associations between potential sources of lead and BLLs. Results: The prevalence of elevated BLLs (>50 µg/L) was 59.5% [GM 56.4 µg/L, 95% CI: 54.1 - 58.7] at six years of age compared to 54.8% [GM 56.5 µg/L, 95% CI: 53.4-59.6] at one year of age. The prevalence of children with BLLs >100 µg/L decreased from 14.4% at one year of age to 8.2% at six years of age (p<0.001). Consumption of peanuts was associated with an increment in BLLs both in the lowest (25th) and highest (90th) percentiles of BLLs. Consumption of bushmeat killed by lead bullets was associated with increments in the higher percentile (75th) of the distribution of the BLLs. Presence of activity with the potential use of lead in the house or neighbourhood was also associated with increased BLLs. These potential sources of lead were common: 10% reported eating peanuts more than once per month, almost 19% reported current meat consumption, and 14% reported the presence of activity with the potential use of lead. Conclusion: We confirm the persistently high prevalence of elevated BLLs in this rural, non-mining site, in south Benin. These results highlight the need for prevention strategies to decrease lead exposure in this population of children.

Blood Lead Levels among Blood Donors and High-Risk Occupational Groups in a Mining Area in Ghana: Implications for Blood Transfusion among Vulnerable Populations.

Lead poisoning has been a major global health problem for decades, and blood transfusion has been suspected as a neglected potential source of lead exposure. Children and pregnant women are most vulnerable to the toxic effects of lead and over 40 percent of blood transfused in Ghana is given to children under 5 years. However, there is little data on the levels of lead in donor blood and the main sources of lead exposure in the Ghanaian population. This study compared blood lead levels (BLL) among selected occupations at risk of lead exposure with healthy blood donors in nonexposed occupations in a Ghanaian mining area. We enrolled 40 participants each from the following high-risk occupational groups: small scale miners, painters/sprayers, drivers/fuel station attendants, and auto-mechanics as well as 40 healthy blood donors (made up of teachers, traders, and office workers). One millilitre of blood was collected from each participant for determination of their BLL, haemoglobin concentration, and blood film morphology. A total of 200 participants made up of 186 (93%) males and 14 (7%) females were enrolled. The mean age of participants was 28.6 ± 8.2 years and their geometric mean (GM) BLL was 6.3 GSD 1.4 µg/dL [95% CI: 6.0 – 6.6]. Participants in high risk occupations had significantly higher GM BLL of 6.7 µg/dL [95% CI :6.4−7.0] compared to 5.0 µg/dL [95% CI: 4.4−5.7] for healthy blood donors [p < 0.001]. The prevalence of elevated BLL (≥5 µg/dL) among the entire study participants, high risk occupations and blood donors was 84.5%, 89.4% and 65% respectively. There was significant association between elevated BLLs and working in an at-risk occupational group [aOR = 3.58, p = 0.014]. Haemoglobin concentration was not significantly associated with elevated BLLs. Basophilic stippling was not observed in any of the blood smears. Blood lead levels were high in blood donors and at-risk occupations in the study area and occupation was associated with elevated BLLs. It is important that measures to safeguard the integrity of donor blood go beyond screening for infectious diseases to include screening individuals in high-risk occupations for lead and other heavy metals to ensure that donor blood from such individuals is safe and does not pose potential danger to the health of vulnerable populations such as children and pregnant women.

Blood Lead Levels in children 2 through 59 months old in Bhutan

Introduction: Pediatric lead exposure has long-term health, public health, and economic consequences; however, it is an underrecognized problem in low and middle-income countries. Our objective was to determine the prevalence of elevated blood lead levels (EBLLs) (greater than or equal to 5mg/dL) and evaluate risk factors for EBLLs in infants and children in two cities in Bhutan. Methods: A cross-sectional study of children 2 through 59 months old was conducted in Thimphu and Phuentsholing, Bhutan during 2018. Blood was obtained by finger-stick and tested using a LeadCare II analyzer (Meridian Bioscience). Data were double entered in EpiData 3.1 and validated. Excel, Prism8, and STATA/IC 15.1 were used for analysis. Results: Among 531 participants, the prevalence of EBLLs was 43.88%. The prevalence of EBLLs in girls and boys was 37.40% (n=262) and 50.19% (n=269), respectively (p= 0.004). The prevalence in Thimphu was 52.35% (n=361), compared to 25.88% (n=170) in Phuentsholing (p less than 0.001). In Thimphu, 70.47% (n=149) of 1 - 4 year old children tested in spring had EBLLs, compared to 51.45% (n=138) in autumn (p=0.001). Of the risk factors assessed, only regularly eating with fingers or hands was significantly associated with EBLLs (p &lt; 0.001). Conclusions: Nearly half of participants in two cities in Bhutan had elevated blood lead levels. Seasonal exposure to lead appears to be present. The high prevalence in this study is alarming. Further studies are urgently needed to both characterize the sources of lead and validate these findings on a larger scale.

Trends in Elevated Blood Lead Levels Using 5 and 10 µg/dL Levels of Concern Among Refugee Children Resettled in Massachusetts, 1998-2015.

Refugee children are known to have a high prevalence of elevated blood lead levels (EBLLs). We sought to determine trends in EBLLs among refugee children during an 18-year period and examine relationships between descriptive characteristics and EBLLs by using 10 µg/dL and 5 µg/dL levels of concern. We retrospectively evaluated refugee health screening data from Massachusetts for 1998 through 2015 for refugee children aged <7 years. We performed bivariate and multivariate analyses of variables including sex, age, region of origin, anemia, intestinal parasites, tuberculosis test results, and anthropometric measurements and used both 5 µg/dL and 10 µg/dL levels of concern for EBLLs. Of 3421 eligible refugee children, 3054 (88.2%) were tested. Using 5 µg/dL and 10 µg/dL levels of concern, 1279 (41.9%) and 241 (7.9%) children, respectively, had EBLLs. Mean BLLs declined steadily from 7.58 µg/dL in 2004 to 4.03 µg/dL in 2015. African (adjusted odds ratio [aOR] = 2.49; 95% confidence interval [CI], 1.81-3.43), East Asian and Pacific (aOR = 1.98; 95% CI, 1.35-2.91), and South-Central Asian (aOR = 2.47; 95% CI, 1.53-4.01) regions of origin and anemia (aOR = 1.50; 95% CI, 1.14 -1.97) were significantly associated with BLLs ≥5 µg/dL. The prevalence of EBLLs among refugees compared with US-born children is high. Because EBBLs increase the risk for neurocognitive impairment in children, public health professionals, policy makers, researchers, refugee resettlement staff members, and health care providers must remain vigilant in screening for lead poisoning and educating refugees about the hazards posed to young children by lead.

Elevated Blood Lead Levels in Infants and Children in Haiti, 2015.

Few studies have reported blood lead levels (BLLs) in Haitian children, despite the known presence of lead from environmental factors such as soil, water, leaded paint and gasoline, improperly discarded batteries, and earthquakes. We sought to determine the prevalence of elevated blood lead levels (EBLLs) among healthy Haitian children. We enrolled children aged 9 months to 6 years from 3 geographic areas in Haiti (coastal, urban, and mountain) from March 1 through June 30, 2015. We obtained anthropometric measurements, household income, potential sources of lead exposure, and fingerstick BLLs from 273 children at 6 churches in Haiti. We considered a BLL ≥5 μg/dL to be elevated. Of 273 children enrolled in the study, 95 were from the coastal area, 78 from the urban area, and 100 from the mountain area. The median BLL was 5.8 μg/dL, with higher levels in the mountain area than in the other areas ( P < .001). BLLs were elevated in 180 (65.9%) children. The prevalence of EBLL was significantly higher in the mountain area (82 of 100, 82.0%; P < .001) than in the urban area (42 of 78, 53.8%) and the coastal area (56 of 95, 58.9%; P < .001). Twenty-eight (10.3%) children had EBLLs ≥10 μg/dL and 3 (1.1%) children had EBLLs ≥20 μg/dL. Exposure to improperly discarded batteries ( P = .006) and living in the mountain area ( P < .001) were significant risk factors for EBLLs. More than half of Haitian children in our study had EBLLs. Public health interventions are warranted to protect children in Haiti against lead poisoning.

Declines in adult blood lead levels in New York City compared with the United States, 2004–2014

ObjectivesTo assess changes in lead exposure in the New York City (NYC) adult population over a 10-year period and to contrast changes with national estimates, overall, and by socio-demographics and smoking status. MethodsWe used measurements of blood lead levels (BLLs) from NYC resident adults who participated in the NYC Health and Nutrition Examination Surveys (HANES) in 2004 and 2013–2014. We compared estimates of geometric means (GM), 95th percentiles, and prevalence of BLL ≥ 5 µg/dL overall and by subgroups over time, with adults who participated in the National HANES (NHANES) 2001–2004 and 2011–2014. ResultsThe GM BLLs among NYC adults declined from 1.79 µg/dL in 2004 to 1.13 µg/dL in 2013–2014 (P < .0001). The declines over this period ranged from 30.1% to 43.2% across socio-demographic groups and smoking status (P < .0001 for all comparisons), and were slightly greater than declines observed nationally. The drop in prevalence of elevated BLLs (≥ 5 µg/dL) was also greater in NYC (4.8–0.5%), compared with NHANES (3.8–2.0%). By 2013–2014, NYC adults with lower annual family income (< $20,000) no longer had higher GM BLLs relative to those with higher incomes (≥ $75,000), a disparity improvement not observed nationally. Likewise, GM BLLs and 95th percentiles for non-Hispanic black adults in NYC were lower than GM BLLs for non-Hispanic white adults. Non-Hispanic Asian adults had the highest GM BLLs compared with other racial/ethnic groups, both in NYC in 2013–14 and nationally in 2011–2014 (1.37 µg/dL, P = .1048 and 1.22 µg/dL, P = .0004, respectively). ConclusionThe lessening of disparity in lead exposure across income groups and decreasing exposure at the high end of the distribution among non-Hispanic black and Asian adults in NYC suggest that regulatory and outreach efforts have effectively targeted these higher exposure risk groups. However, Asian adults still had the highest average BLL, suggesting a need for enhanced outreach to this group. Local surveillance remains an important tool to monitor BLLs of local populations and to inform initiatives to reduce exposures in those at highest risk.

Blood Lead Levels and Risk Factors for Lead Exposure in a Pediatric Population in Ho Chi Minh City, Vietnam.

Although lead recycling activities are a known risk factor for elevated blood levels in South East Asia, little is known regarding the prevalence of and risk factors for elevated blood lead levels (BLL) among the general pediatric population in Vietnam. This study is a cross-sectional evaluation of 311 children from Children’s Hospital #2 in Ho Chi Minh City, Vietnam. Capillary blood lead testing was performed using the LeadCare II. Mean BLLs were 4.97 μg/dL (Standard Deviation (SD) 5.50), with 7% of the participants having levels greater than 10 μg/dL. Living in Bing Duong province (OR 2.7, 95% CI 1.4–5.6.1) or the Dong Nai province (OR 2.3, 95% CI 1.0–5.1) and having an age greater than 12 months (OR 6.0, 95% CI 3.1–11.8) were associated with higher BLLs. The prevalence of elevated BLLs in Vietnam is consistent with other SE Asian countries. Mean BLLs in Ho Chi Minh City are markedly less than those seen in a separate study of children living near lead recycling activities. Additional evaluation is necessary to better detail potential risk factors if screening is to be implemented within Vietnam.

Analysis of multiple‐variable missing‐not‐at‐random survey data for child lead surveillance using NHANES

Although ongoing, multi-topic surveys form the basis of public health surveillance in many countries, their utility for specific subject matter areas can be limited by high proportions of missing data. For example, the National Health and Examination Survey is the main resource for surveillance of elevated blood lead levels (EBLLs) in US children, but key predictor variables are missing for as many as 35% of respondents. Using a Bayesian framework, we formulate a t-distributed Heckman selection model applicable to the case of multiple missing-not-at-random variables in the context of a complex survey design. We demonstrate the utility of the results by calculating prevalence estimates for lead levels exceeding 2.5, 5.0, and 10.0 µg/dL among children 1 to 5 years of age for a variety of time points and geographies by applying the coefficients to data from the American Community Survey from the US Census. We present a protocol for estimating posterior distributions of parameters using Gibbs and grid sampling steps. Stark disparities in the prevalence of EBLL by race/ethnicity, age of housing, and poverty are readily quantified, and three- to five-fold differences in predicted prevalence across geographies within the US are presented. We are able to conduct multivariate analyses of EBLLs that incorporate the crucial variable age of housing, analyses that have not been previously available using these data. This represents an expansion of the utility of National Health and Examination Survey that is likely to be relevant to many similar ongoing, multi-topic health surveillance efforts. Copyright © 2016 John Wiley & Sons, Ltd.

Risk factors for elevated blood lead levels among children aged 6-36 months living in Greece.

Childhood lead poisoning remains a critical environmental health concern because even low blood lead levels (BLLs) can result in permanent adverse health effects. Social factors and living conditions have been correlated with BLLs. There is no recent survey about the prevalence of elevated BLLs among children in Greece. The purpose of this study was to assess BLLs among children aged 6-36 months born and living in Greece and to evaluate their association with demographic, socio-economic and housing conditions. In a cross-sectional hospital-based study including 814 randomly selected children aged 6-36 months, BLLs and haematological parameters were evaluated. A questionnaire investigating demographic and socio-economic conditions was completed in all children. Statistical analysis was performed using STATA for Windows v.8.5, and P < 0.05 was considered statistically significant. The mean BLLs of the population were 2.78 (SD = 2.34) µg/dl, and the median was 2.02 µg/dl; 11.7% had BLLs above 5 µg/dl, while 15 children (1.8%) exceeded 10 µg/dl. Being a toddler, being Roma or Asian, living in an industrial/low-income neighbourhood or in an old house, using traditional herbs and/or spices and having a mother with a manual occupation were independent risk factors for elevated BLLs. Lead exposure remains a threat for optimal health especially for toddlers and children of socio-economically disadvantaged families living in Greece. A nationwide survey to assess lead exposure in children is necessary to guide prevention governmental policies.

Blood lead levels in children aged 0-6 years old in Hunan Province, China from 2009-2013.

ObjectivesThe aim of this study is to describe blood lead levels (BLLs) and the prevalence of elevated blood lead levels (EBLLs) in children aged 0–6 years old and to analyze the BLL trend in children from 2009 to 2013 in China.MethodsA total of 124,376 children aged 0–6 years old were recruited for this study from January 1st 2009 to December 31st 2013. Their blood lead levels were analyzed using atomic absorption spectrometry.ResultsThe median BLL was 64.3 μg/L (IQR: 49.6–81.0), and the range was 4.3–799.0 μg/L. Blood lead levels were significantly higher in boys (66.0 μg/L) than in girls (61.9 μg/L) (P<0.001). The overall prevalence of BLLs≥100 μg/L was 10.54% in children aged 0–6 years in Hunan Province. Between 2009 and 2013, the prevalence of EBLLs (≥100 μg/L) decreased from 18.31% to 4.26% in children aged 0–6 years and increased with age. The prevalence of EBLLs has dramatically decreased in two stages (2009–2010 and 2012–2013), with a slight fluctuation in 2010 and 2011.ConclusionsBoth BLLs and the prevalence of EBLLs in children aged 0–6 years old declined substantially from 2009 to 2013 in Hunan Province; however, both remain at unacceptably high levels compared to developed countries. Comprehensive strategies are required to further reduce blood lead levels in children.

Surveillance of childhood blood lead levels in 11 cities of China

Exposure to lead can be deleterious to children's health. Surveillance for blood lead levels (BLLs) is reported every year in the USA and some other countries. However, such reports are lacking in China which has the world's largest population of children. In this study, we provided the latest nationally representative data on BLLs among Chinese children living in cities, described the change in BLLs since 2004, and explored the risk factors for elevated BLLs (EBLLs) among children. We studied 12 693 children aged 0-6 years in 2004 and 11 255 children aged 0-6 years in 2010. We evaluated the average BLLs and the prevalence of EBLLs, and a multivariate logistic regression model was used to estimate predictors of EBLLs. The geometric mean BLLs of children aged 0-6 years dropped by 16% (from 46.38 ± 2.10 μg/L in 2004 to 38.95 ± 1.83 μg/L in 2010), while the prevalence of EBLLs dropped by 87% (from 9.78% in 2004 to 1.32% in 2010). In a multivariate analysis, the following factors were associated with EBLLs: (1) children being cared for at home or at a boarding nursery (compared to children being cared for in a day nursery), (2) children having fathers with a lower education level, and (3) children often eating popcorn and chewing fingernails or sucking fingers were associated with EBLLs. The results of this study demonstrated a substantial decline in BLLs from 2004 to 2010 among Chinese children 0-6 years living in cities. However, these levels were higher than levels in countries, such as the USA, Canada, Japan and Sweden. These data demonstrate that Chinese children's lead exposure remains a public health problem that requires additional effort and resources.

Blood lead levels in children after phase-out of leaded gasoline in Kinshasa, the capital of Democratic Republic of Congo (DRC)

BackgroundThe phasing out of lead from gasoline has resulted in a significant decrease in blood lead levels (BLLs) in children during the last two decades. Tetraethyl lead was phased out in DRC in 2009. The objective of this study was to test for reduction in pediatric BLLs in Kinshasa, by comparing BLLs collected in 2011 (2 years after use of leaded gasoline was phased out) to those collected in surveys conducted in 2004 and 2008 by Tuakuila et al. (when leaded gasoline was still used).MethodsWe analyzed BLLs in a total of 100 children under 6 years of age (Mean ± SD: 2.9 ± 1.6 age, 64% boys) using inductively coupled argon plasma mass spectrometry (ICP – MS).ResultsThe prevalence of elevated BLLs (≥ 10 μg/dL) in children tested was 63% in 2004 [n = 100, GM (95% CI) = 12.4 μg/dL (11.4 – 13.3)] and 71% in 2008 [(n = 55, GM (95% CI) = 11.2 μg/dL (10.3 – 14.4)]. In the present study, this prevalence was 41%. The average BLLs for the current study population [GM (95% CI) = 8.7 μg/dL (8.0 – 9.5)] was lower than those found by Tuakuila et al. (F = 10.38, p <0.001) as well as the CDC level of concern (10 μ/dL), with 3% of children diagnosed with BLLs ≥ 20 μg/dL.ConclusionThese results demonstrate a significant success of the public health system in Kinshasa, DRC-achieved by the removal of lead from gasoline. However, with increasing evidence that adverse health effects occur at BLLs < 10 μg/dL and no safe BLLs in children has been identified, the BLLs measured in this study continue to constitute a major public health concern for Kinshasa. The emphasis should shift to examine the contributions of non-gasoline sources to children’s BLLs: car batteries recycling in certain residences, the traditional use of fired clay for the treatment of gastritis by pregnant women and leaded paint.

Blood lead levels in the adult population living in France the French Nutrition and Health Survey (ENNS 2006–2007)

BackgroundThe French Nutrition and Health Survey (ENNS) was conducted in order to describe food consumption and levels of various biomarkers in the general population. In this paper, we aimed to assess the distribution of blood lead levels (BLL) in the adult population living in France. MethodENNS was a cross-sectional survey carried out in the general population. Participants (18–74years of age) were sampled using a three-stage probability design stratified by geographical areas and degrees of urbanization. Collected data included biochemical samples, anthropometric measurements, socio-demographic characteristics, and environmental and occupational exposure. ResultsIn 2006/2007, 2029 adults were included in the survey on lead. The blood lead geometric mean (GM) in the population living in France was 25.7μg/L [24.9–26.5]. The overall prevalence of elevated BLL (>100μg/L) was 1.7% [1.1–2.3%]. Levels were significantly higher in males than in females, and increased with age, smoking status and alcohol consumption. Other factors significantly associated with BLL were leisure activities, occupational category, age of housing unit, birth place and shellfish/crustacean consumption. ConclusionFor the first time a survey provides national estimates of BLL for the adult population in France. Comparison with results from a previous study among men aged 18–28years showed that the GM dropped more than 60% in the last 10years. The distribution of BLL in France was quite similar to that observed in other European countries.

Enns: The French Nutrition &amp; Health Survey-Blood Lead Levels in the French Adult Population

ISEE-0374 Background and Objectives: The French Nutrition & Health Survey (ENNS) was carried out by the French Institute for Public Health Surveillance in 2006-2007. The main objectives were to explore food consumption and levels of various biomarkers in the general population. The aim of the present study was to assess blood lead levels (BLL) in the French adult population. Methods: ENNS is a cross-sectional study in the general population. Participants (18 to 74 years of age) were sampled using a three-stage probability design stratified by geographical areas and degrees of urbanization. Data on individual characteristics, eating habits, occupational and environmental exposure were collected through interviews and self-administered questionnaires. Blood samples were collected and analysed using standardized procedures. Sample weights and complex sample design were taken into account in statistical analyses to produce unbiased and representative estimates. Results: The blood lead geometric mean in the French population was 25.7 μg/L [CI95: 24.9-26.5]. The overall prevalence of elevated BLL (>100 μg/L) was 1.6% [CI95: 1.1%-2.1%]. The median was 25 μg/L and the 95th percentile was 73 μg/L. Comparison with results from previous studies show that the geometric mean of BLL (in male young adults) dropped by 50% in 10 years. In 2006, levels were significantly higher (P < 0.0001) for males than for females, and increased (P < 0.0001) with age, tobacco or alcohol consumption. Others factors associated with BLL were identified including leisure activities, socio-professional status, age of housing, birth country and shellfish consumption. Conclusion: The findings from the ENNS-lead study demonstrate that BLL in the French population has declined during recent years, and is still influenced by age, sex, smoking habits, and alcohol consumption. The distribution of BLL in France was quite similar to that observed in other European countries (Germany and Czech Republic).

Seasonality and trend in blood lead levels of New York State children.

BackgroundEnvironmental exposure to lead remains a significant health problem for children. The costs of lead exposure in children are estimated to be considerably more than other childhood diseases of environmental origin. While long-term trends in blood lead levels (BLLs) among children are declining, seasonal variation persists. Cross-sectional studies have found a peak in summer months. Part of this variation may be due to increased exposure to lead paint on window sills and through increased contact with soils containing lead during the summer. The current study represents the largest published population-based study on seasonality and trends in the BLLs of children to date. In addition, the results offer a comparison of recent data on seasonality of BLLs in New York State children, to studies conducted over the past three decades.Methods262,687 New York State children born between 1994 and 1997 were screened for blood lead within 2 weeks of their first or second birthdays. Time series analyses of blood lead data from these children were conducted to study the seasonality and trends of BLLs.ResultsChildren's blood lead values showed a distinct seasonal cycle on top of a long-term decreasing trend. The geometric mean BLL declined by about 24% for children born between 1994 and 1997. The prevalence of elevated BLLs in two-year-olds was almost twice that in one-year-olds over the time period. Nearly twice as many children had elevated BLLs in the late summer compared to late winter/early spring. In this and previous cross-sectional studies, the amount of seasonality as a proportion of the mean ranged between 15% and 30%.ConclusionPediatricians should be aware of the seasonality of BLLs. For example, if a two-year-old receives a borderline result during the winter, it is possible that the levels would have been higher if he had been tested during the summer. However, physicians should continue to screen children at their normally scheduled well-child visits rather than delaying until summertime and possibly postponing the discovery of an elevated BLL. Age, season, and time trends still need to be considered in lead studies and result interpretation.

Preschool children's lead levels in rural communities of Zhejiang province, China

The aim of the study was to determine mean blood lead levels (BLLs) and prevalence of elevated BLLs among preschool children aged 3-6 years in Zhejian rural communities, China. Data were gathered by means of a questionnaire and blood lead analyses for 217 children who attended six randomly selected kindergartens. BLLs ranged from 25-437 microg/l. Arithmetic mean was 95 microg/l and standard deviation was 56 microg/l. BLLs of 63 samples (29.0%) were > or =100 microg/l. Children with BLLs > or =100 microg/l came from families with a higher proportion of their fathers or mothers working in conditions of potential exposure to lead, as compared to those with BLLs <100 microg/l (P < 0.01). A significantly higher proportion of children with BLLs > or =100 micro/l lived in buildings that were located near small industries, such as mechanics, furniture, or paint shop, as compared to those with BLLs <100 microg/l (P < 0.01). In conclusion, the data indicate that high levels of childhood lead exposures even prevail in rural communities and deserve authorities' attention. With the recent ban of leaded gasoline in China, emphasis should shift to other sources of exposure in children.

Elevated Blood Lead Levels Among Internationally Adopted Children—United States, 1998

Lead poisoning has been reported recently among Chinese children adopted by U.S. citizens. However, little is known about the prevalence of elevated blood lead levels (BLLs) among adoptees from China and other countries. Persistent sources of lead exposure outside the United States include leaded gasoline exhaust; industrial emissions; cottage industries (e.g., battery breaking and recycling plants); traditional medicines; and some cosmetics, ceramic ware, and foods. In 1998, approximately 15,000 orphans from countries outside the United States who were adopted abroad or were to be adopted in the United States by U.S. citizens were issued U.S. immigrant visas-a nearly two-fold increase over 1988 (L. Lewis, Immigrant and Visa Control and Reporting Division, VISA Office, Bureau of Consular Affairs, U.S. State Department, personal communication, August 1999). Some orphans have been abandoned for extended periods and have no obtainable medical history. Immigrants aged <15 years are not required to have serologic or blood tests either in their country of origin or on entry into the United States unless exposure to syphilis or human immunodeficiency virus is suspected. To obtain reports on the prevalence of elevated BLLs (> or =10 microg/dL) among international adoptees, CDC contacted 12 international adoption medical specialists identified through the Joint Council on International Children's Services and two collaborating medical specialists. This report summarizes the results of that investigation, which suggest that international adoptees may arrive in the United States with elevated BLLs.

Adult Blood Lead Epidemiology and Surveillance—United States, 1992-1994

Lead exposure can result in acute or chronic adverse effects in multiple organ systems, ranging from subclinical changes in function to symptomatic, life-threatening toxicity. Despite improvements in public health policies and substantial reductions in blood lead levels (BLLs) in adults, lead exposure remains an important health problem worldwide. Approximately 95% of all elevated BLLs reported among adults in the United States are work-related, and recent research has raised concerns regarding the toxicity of BLLs as low as 5 μg/dL. CDC's state-based Adult Blood Lead Epidemiology and Surveillance (ABLES) program tracks laboratory-reported elevated BLLs. To update rate trends and identify industry subsectors and nonoccupational activities with high lead exposures, CDC collected and analyzed 2008--2009 data from 40 state ABLES programs. The results of that analysis indicated that a decline in the prevalence of elevated BLLs (≥25 μg/dL) was extended, from 14.0 per 100,000 employed adults in 1994 to 6.3 in 2009. Industry subsectors with the highest numbers of lead-exposed workers were battery manufacturing, secondary smelting and refining of nonferrous metals, and painting and paper hanging. The most common nonoccupational exposures to lead were shooting firearms; remodeling, renovating, or painting; retained bullets (gunshot wounds); and lead casting. The findings underscore the need for government agencies, employers, public health professionals, health-care providers, and worker-affiliated organizations to increase interventions to prevent workplace lead exposure, and the importance of conducting lead exposure surveillance to assess the effectiveness of these interventions.