Source Of Lead Exposure Research Articles

E-Waste Informal Recycling: An Emerging Source of Lead Exposure in South America

BackgroundPrimitive electronic waste (e-waste) recycling creates exposures to several hazardous substances including lead. In Uruguay, primitive recycling procedures are a significant source of lead exposure. ObjectivesThe aim of this study was to examine lead exposure in blood lead levels (BLLs) in low-income children exposed to lead through burning cables. MethodsA sample of children and adolescents exposed to lead through burning cable activities were assessed at the Department of Toxicology in Montevideo, Uruguay, between 2010 and 2014. Soil lead levels of residences were taken shortly after their assessment. FindingsThe final sample included 69 children and adolescents (mean age 7.89 years). More than 66% of participants had an additional source of lead exposure—manual gathering of metals—and <5% were exposed to lead through landfills or paint. Average BLLs at first consultation were 9.19 ug/dL and lower at the second measurement (5.86 μg/dL). Data from soil lead levels ranged from 650 to 19,000 mg of lead/kg of soil. The interventions conducted after the assessment included family education in the clinic and at home, indoor and outdoor remediation. We found a decrease in BLLs of 6.96 μg/dL. Older children had lower BLLs (r = −0.24; P = 0.05). Statistical analyses also showed that children living in areas with higher soil lead levels had significantly higher BLLs (r = 0.50; P < 0.01). Additionally, we found greater BLLs from burning cable activities when children had been exposed to lead-based paint (r = 0.23; P < 0.1). ConclusionAmong children exposed to e-waste recycling, the most common additional source of lead exposure was the manual gathering of metals. The average BLL among children and adolescents in this study is higher than the BLLs currently suggested in medical intervention. Future research should focus on exploring effective interventions to reduce lead exposure among this vulnerable group.

Proximity of residence to an old mineral storage site in Chile and blood lead levels in children.

Evidence suggests that an old mineral storage site removed in 1998 due to high lead content, remains as a source of exposure in the city of Antofagasta, Chile. The aim was to determine the association between blood lead levels in children and the residential proximity to the old mineral storage site. A cross sectional study was conducted with 185 children aged 7 to 16 years. The outcome variable was blood lead levels measured in 2005. The exposure variable was the distance between the current residence and the old mineral storage site. The distance was measured in meters by Geographic Information System (GIS). The median blood lead level in 2005 was 3.3μg/dL (interquartile range ‒ IQR: 2.0-4.3). A significant inverse association was found between the residential distance to the old mineral storage site and the blood lead levels in children, after adjusting by confounders (β: -0.04; 95%CI: -0.09; -0.01). This result suggests that the old mineral storage site continues to be a source of lead exposure for the children living nearby.

Assessment of blood lead level declines in an area of historical mining with a holistic remediation and abatement program

Lead exposure and blood lead levels (BLLs) in the United States have declined dramatically since the 1970s as many widespread lead uses have been discontinued. Large scale mining and mineral processing represents an additional localized source of potential lead exposure in many historical mining communities, such as Butte, Montana. After 25 years of ongoing remediation efforts and a residential metals abatement program that includes blood lead monitoring of Butte children, examination of blood lead trends offers a unique opportunity to assess the effectiveness of Butte’s lead source and exposure reduction measures. This study examined BLL trends in Butte children ages 1–5 (n= 2796) from 2003–2010 as compared to a reference dataset matched for similar demographic characteristics over the same period. Blood lead differences across Butte during the same period are also examined. Findings are interpreted with respect to effectiveness of remediation and other factors potentially contributing to ongoing exposure concerns. Reference population comparisonBLLs from Butte were compared with a reference dataset (n=2937) derived from the National Health and Nutrition Examination Survey. The reference dataset was initially matched for child age and sample dates. Additional demographic factors associated with higher BLLs were then evaluated. Weights were applied to make the reference dataset more consistent with the Butte dataset for the three factors that were most disparate (poverty-to-income ratio, house age, and race/ethnicity). A weighted linear mixed regression model showed Butte geometric mean BLLs were higher than reference BLLs for 2003–2004 (3.48vs. 2.05µg/dL), 2005-2006 (2.65vs. 1.80µg/dL), and 2007-2008 (2.2vs. 1.72µg/dL), but comparable for 2009–2010 (1.53vs. 1.51µg/dL). This trend suggests that, over time, the impact of other factors that may be associated with Butte BLLs has been reduced. Comparison across ButteNeighborhood differences were examined by dividing the Butte dataset into the older area called “Uptown”, located at higher elevation atop historical mine workings, and “the Flats”, at lower elevation and more recently developed. Significant declines in BLLs were observed over time in both areas, though Uptown had slightly higher BLLs than the Flats (2003–2004: 3.57vs. 3.45µg/dL, p=0.7; 2005–2006: 2.84vs. 2.52µg/dL, p=0.1; 2007–2008: 2.58vs. 1.99µg/dL, p=0.001; 2009–2010: 1.71vs. 1.44µg/dL, p=0.02). BLLs were higher when tested in summer/fall than in winter/spring for both neighborhoods, and statistically higher BLLs were found for children in Uptown living in properties built before 1940. Neighborhood differences and the persistence of a greater percentage of high BLLs (>5µg/dL) in Butte vs. the reference dataset support continuation of the home lead abatement program. ConclusionsButte BLL declines likely reflect the cumulative effectiveness of screening efforts, community-wide remediation, and the ongoing metals abatement program in Butte in addition to other factors not accounted for by this study. As evidenced in Butte, abatement programs that include home evaluations and assistance in addressing multiple sources of lead exposure can be an important complement to community-wide soil remediation activities.

Fountain Autopsy to Determine Lead Occurrence in Drinking Water

Exposure to lead in drinking water poses a risk for various adverse health effects, and significant efforts have been made to monitor and eliminate lead exposure in drinking water. This study focused on the localization of lead exposure from 71 drinking water fountains in nonresidential buildings in order to determine the source of elevated lead and understand the effects of fountains associated with lead concentration in drinking water. Drinking water fountains containing lead-lined cooling tanks and brass fittings were found to release lead concentrations in excess of 10 μg/L, and fountains with low or infrequent usage and those with cooling tanks produced the highest concentrations (in excess of 20 μg/L) of lead. One particular fountain model found at several locations throughout the institution was associated with some of the highest lead concentrations measured throughout the study. This fountain was recalled in the United States, but not in Canada. This article adds to existing research demonstrating that drinking water fountains are a potentially significant and underappreciated source of lead exposure in nonresidential buildings.

Chronic lead poisoning magnifies bone detrimental effects in an ovariectomized rat model of postmenopausal osteoporosis

Lead (Pb) is a persistent environmental contaminant that is mainly stored in bones being an important source of endogenous lead exposure during periods of increased bone resorption as occurs in menopause. As no evidence exists of which bone biomechanical properties are impaired in those elderly women who had been exposed to Pb during their lifetime, the aim of the present study is to discern whether chronic lead poisoning magnifies the deterioration of bone biology that occurs in later stages of life. We investigated the effect of Pb in the femora of ovariectomized (OVX) female Wistar rats who had been intoxicated with 1000ppm of Pb acetate in drinking water for 8 months. Structural properties were determined using a three-point bending mechanical test, and geometrical and material properties were evaluated after obtaining the load/deformation curve. Areal Bone Mineral Density (BMD) was estimated using a bone densitometer. Femoral histomorphometry was carried out on slices dyed with H&E (Hematoxylin and Eosin). Pb and OVX decreased all structural properties with a higher effect when both treatments were applied together. Medullar and cortical area of femurs under OVX increased, allowing the bone to accommodate its architecture, which was not observed under Pb intoxication. Pb and OVX significantly decreased BMD, showing lead treated ovariectomized rats (PbOVX) animals the lowest BMD levels. Trabecular bone volume per total volume (BV/TV%) was decreased in OVX and PbOVX animals in 54% compared to the control animals (p<0.001). Pb femurs also showed 28% less trabeculae than the control (p<0.05). We demonstrated that Pb intoxication magnifies the impairment in bone biomechanics of OVX rats with a consequent enhancement of the risk of fracture. These results enable the discussion of the detrimental effects of lead intoxication in bone biology in elderly women.

A population-based study on blood lead levels in blood donors.

Recent studies suggested that blood transfusion may represent a significant source of lead exposure in premature infants. Objectives of this study were to determine blood lead levels (BLLs) in a representative sample of blood donors and to identify risk factors associated with BLLs of 0.15 µmol/L or more. A study was conducted in 2006 to 2007 in 49 drive sites in Quebec. Individuals who qualified for blood donation were eligible to participate. Information was harvested from blood donor file and a standardized self-administered questionnaire. Lead analysis was performed by inductively coupled plasma mass spectrometry. Data on Quebec blood donors from 2003 to 2006 (n = 320,543) were used to establish a reference population. Geometric mean (GM) and 95% confidence interval (CI) were used to describe the results. The project was approved by an ethics committee. Of 6715 eligible individuals, 3490 participated (1392 women and 2098 men). Their mean age was 46.5 years. Results were weighted for region, sex, and age. The GM of BLLs was 0.082 µmol/L (95% CI, 0.027-0.247; range, 0.011-2.90 µmol/L). BLLs of more than 0.15 µmol/L were found in 15.5% of participants. In multivariate analysis, BLLs were mainly explained by age and sex of participants (p < 0.001). A significant association was also found between BLLs and the region of residence, education level, dwelling age, occupational and leisure activities at high risk for lead exposure, smoking, and alcohol intake (p < 0.001). BLL in blood donors is strongly explained by sex and age, a fact that can be taken into consideration when transfusing neonates.

Use of a Cumulative Exposure Index to Estimate the Impact of Tap Water Lead Concentration on Blood Lead Levels in 1- to 5-Year-Old Children (Montréal, Canada)

BackgroundDrinking water is recognized as a source of lead (Pb) exposure. However, questions remain about the impact of chronic exposure to lead-contaminated water on internal dose.ObjectiveOur goal was to estimate the relation between a cumulative water Pb exposure index (CWLEI) and blood Pb levels (BPb) in children 1–5 years of ages.MethodsBetween 10 September 2009 and 27 March 2010, individual characteristics and water consumption data were obtained from 298 children. Venous blood samples were collected (one per child) and a total of five 1-L samples of water per home were drawn from the kitchen tap. A second round of water collection was performed between 22 June 2011 and 6 September 2011 on a subsample of houses. Pb analyses used inductively coupled plasma mass spectroscopy. Multiple linear regressions were used to estimate the association between CWLEI and BPb.ResultsEach 1-unit increase in CWLEI multiplies the expected value of BPb by 1.10 (95% CI: 1.06, 1.15) after adjustment for confounders. Mean BPb was significantly higher in children in the upper third and fourth quartiles of CWLEI (0.7–1.9 and ≥ 1.9 μg/kg of body weight) compared with the first (< 0.2 μg/kg) after adjusting for confounders (19%; 95% CI: 0, 42% and 39%; 95% CI: 15, 67%, respectively). The trends analysis yielded a p-value < 0.0001 after adjusting for confounders suggesting a dose–response relationship between percentiles of CWLEI and BPb.ConclusionsIn children 1–5 years of age, BPb was significantly associated with water lead concentration with an increase starting at a cumulative lead exposure of ≥ 0.7 μg Pb/kg of body weight. In this age group, an increase of 1 μg/L in water lead would result in an increase of 35% of BPb after 150 days of exposure.CitationNgueta G, Abdous B, Tardif R, St-Laurent J, Levallois P. 2016. Use of a cumulative exposure index to estimate the impact of tap water lead concentration on blood lead levels in 1- to 5-year-old children (Montreal, Canada). Environ Health Perspect 124:388–395; http://dx.doi.org/10.1289/ehp.1409144

Uso de cerámica vidriada como fuente de exposición a plomo en niños indígenas de zonas marginadas de Oaxaca, México

To find out whether the use of lead-glazed ceramic (LGC) is associated with blood lead levels in indigenous schoolchildren from Oaxaca, México. We evaluated LGC use at home as a primary source of lead exposure in 387 indigenous schoolchildren in Oaxaca in May 2001. We found an adjusted difference of 3.9μg/dl (p<0.01) in blood lead levels (BLL) among children reporting to use (82%) LGC at home vs those who didn't. BL levels greater or equal than 10 and 20 μg/dl were observed in 60 and 27% of children, respectively. Lead poisoning from LGC use could remain a concern for public health in Mexico, where there is a need to provide care and further study to verify its effect on BLL.

Levels and source apportionment of children's lead exposure: Could urinary lead be used to identify the levels and sources of children's lead pollution?

As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. However, the collection of blood samples for use as an indicator of lead pollution is not always feasible in most cohort or longitudinal studies, especially those involving children health. To evaluate the potential use of urinary lead as an indicator of exposure levels and source apportionment, accompanying with environmental media samples, lead concentrations and isotopic measurements (expressed as 207Pb/206Pb, 208Pb/206Pb and 204Pb/206Pb) were investigated and compared between blood and urine from children living in the vicinities of a typical coking plant and lead-acid battery factory. The results showed urinary lead might not be a preferable proxy for estimating blood lead levels. Fortunately, urinary lead isotopic measurements could be used as an alternative for identifying the sources of children's lead exposure, which coincided well with the blood lead isotope ratio analysis.

Household interventions for preventing domestic lead exposure in children.

Lead poisoning is associated with physical, cognitive and neurobehavioural impairment in children and trials have tested many household interventions to prevent lead exposure. This is an update of the original review by the same authors first published in 2008. To determine the effectiveness of household interventions in preventing or reducing lead exposure in children as measured by reductions in blood lead levels and/or improvements in cognitive development. We identified trials through electronic searches of CENTRAL (2012, Issue 1), MEDLINE (1948 to January Week 1 2012), EMBASE (1980 to Week 2 2012), CINAHL (1937 to January 2012), PsycINFO (1887 to January Week 2 2012), ERIC (1966 to January 2012), Sociological Abstracts (1952 to January 2012), Science Citation Index (1970 to 20 January 2012), ZETOC (20 January 2012), LILACS (20 January 2012), Dissertation Abstracts (late 1960s to January 2012), ClinicalTrials.gov (19 January 2012), Current Controlled Trials (19 January 2012), Australian New Zealand Clinical Trials Registry (19 January 2012) and the National Research Register Archive. We also contacted experts to find unpublished studies. Randomised and quasi-randomised controlled trials of household educational or environmental interventions to prevent lead exposure in children where at least one standardised outcome measure was reported. Two authors independently reviewed all eligible studies for inclusion, assessed risk of bias and extracted data. We contacted trialists to obtain missing information. We included 14 studies (involving 2656 children). All studies reported blood lead level outcomes and none reported on cognitive or neurobehavioural outcomes. We put studies into subgroups according to their intervention type. We performed meta-analysis of both continuous and dichotomous data for subgroups where appropriate. Educational interventions were not effective in reducing blood lead levels (continuous: mean difference (MD) 0.02, 95% confidence interval (CI) -0.09 to 0.12, I(2) = 0 (log transformed); dichotomous ≥ 10µg/dL (≥ 0.48 µmol/L): relative risk (RR) 1.02, 95% CI 0.79 to 1.30, I(2)=0; dichotomous ≥ 15µg/dL (≥ 0.72 µmol/L): RR 0.60, 95% CI 0.33 to 1.09, I(2) = 0). Meta-analysis for the dust control subgroup also found no evidence of effectiveness (continuous: MD -0.15, 95% CI -0.42 to 0.11, I(2) = 0.9 (log transformed); dichotomous ≥ 10µg/dL (≥ 0.48 µmol/L): RR 0.93, 95% CI 0.73 to 1.18, I(2) =0; dichotomous ≥ 15µg/dL (≥ 0.72 µmol/L): RR 0.86, 95% CI 0.35 to 2.07, I(2) = 0.56). When meta-analysis for the dust control subgroup was adjusted for clustering, no statistical significant benefit was incurred. The studies using soil abatement (removal and replacement) and combination intervention groups were not able to be meta-analysed due to substantial differences between studies. Based on current knowledge, household educational or dust control interventions are ineffective in reducing blood lead levels in children as a population health measure. There is currently insufficient evidence to draw conclusions about the effectiveness of soil abatement or combination interventions.Further trials are required to establish the most effective intervention for prevention of lead exposure. Key elements of these trials should include strategies to reduce multiple sources of lead exposure simultaneously using empirical dust clearance levels. It is also necessary for trials to be carried out in developing countries and in differing socioeconomic groups in developed countries.

Alluvial and riparian soils as major sources of lead exposure in young children in the Philippines: the role of floods.

The objective of this paper was to determine the prevalence and sources of high lead (Pb) exposure among children in Bulacan, Philippines. A total of 150 children (6-7 years old) and their caregivers were studied. Lead was analyzed in children hair and deciduous teeth. Sources of lead exposure were determined by caregiver interview and Pb analysis of house soil, drinking faucet water, air, and water from seven Bulacan rivers. Lead was positive in 91.3% of children's hair (MC or median concentration = 8.9 μg/g; range = 0-38.29), in 46.2% of the teeth (MC = 0.000 μg/mg in positive samples; range = 0.00-0.020), in 100% of soil (MC = 27.06 mg/kg; range = 3.05-1155.80), in 21.1% of air (MC = 0 μg/Ncm; range = 0-0.10), in 4% of house, faucet water (MC = 0.0 ppm; range = 0-40). There was a significant correlation (Spearman's rho) between Pb in children's hair and soil (r = 0.195; p = 0.017) and between Pb in house water and outdoor air (r = 0.616; p = 0.005). There is no significant correlation between Pb in children's hair and teeth. None of the potential sources of Pb from interview were related to lead exposure in the children. Water from seven Bulacan rivers was 100% positive for lead (MC = 70.00 ppb; range = 30-90). Widespread flooding with river overflow occurred in Bulacan in 2009 which likely caused lead contamination of the soil. There was no significant difference in the lead concentration of the soil whether near or far from the river (p = 0.205, Mann-Whitney U test). High lead exposure in children in Bulacan is likely from soil contaminated by lead-polluted rivers during flooding. In areas where flooding is common, alluvial and riparian soils from polluted rivers are important sources of lead exposure in children.

An International Perspective on Lead Poisoning

Lead is one of the most useful and toxic metals. The primary sources of lead exposure are leaded petrol, industrial uses, lead paints and consumer products. Although mean blood lead levels have dec...

Chinese talismans as a source of lead exposure

We describe a case of lead exposure after prolonged intake of ashes from burnt Chinese talismans. A 41-year-old woman presented with elevated blood lead level during screening for treatable causes of progressive weakness in her four limbs, clinically compatible with motor neuron disease. The source of lead exposure was confirmed to be Chinese talismans obtained from a religious practitioner in China. The patient was instructed to burn the Chinese talismans to ashes, and ingest the ashes dissolved in water, daily for about 1 month. Analysis of the Chinese talismans revealed a lead concentration of 17 342 µg/g (ppm).

Exposure of young children to household water lead in the Montreal area (Canada): The potential influence of winter-to-summer changes in water lead levels on children's blood lead concentration

Drinking water represents a potential source of lead exposure. The purpose of the present study was to estimate the magnitude of winter-to-summer changes in household water lead levels (WLLs), and to predict the impact of these variations on BLLs in young children. A study was conducted from September, 2009 to March, 2010 in 305 homes, with a follow-up survey carried out from June to September 2011 in a subsample of 100 homes randomly selected. The first 1-L sample was drawn after 5min of flushing, followed by a further 4 consecutive 1-L samples after 30min of stagnation. Non-linear regression and general linear mixed models were used for modelling seasonal effects on WLL. The batchrun mode of Integrated Exposure Uptake Biokinetic (IEUBK) model was used to predict the impact of changes in WLL on children's blood lead levels (BLLs). The magnitude of winter-to-summer changes in average concentrations of lead corresponded to 6.55μg/L in homes served by lead service lines (LSL+ homes) and merely 0.30μg/L in homes without lead service lines. For stagnant samples, the value reached 10.55μg/L in ‘LSL+ homes’ and remained very low (0.36μg/L) in ‘LSL− homes’. The change in the probability of BLLs ≥5μg/dL due to winter-to-summer changes in WLL was increased from <5% (in winter) to about 20% (in summer) in children aged 0.5–2years. The likelihood of having BLLs ≥5μg/dL in young children during warm months was reduced by at least 40% by flushing tap-water.

Lead exposure from aluminum cookware in Cameroon

Blood lead levels have decreased following the removal of lead from gasoline in most of the world. However, numerous recent studies provide evidence that elevated blood lead levels persist in many low and middle-income countries around the world at much higher prevalence than in the more developed countries. One potential source of lead exposure that has not been widely investigated is the leaching of lead from artisanal aluminum cookware, which is commonly used in the developing world.Twenty-nine samples of aluminum cookware and utensils manufactured by local artisans in Cameroon were collected and analyzed for their potential to release lead during cooking. Source materials for this cookware included scrap metal such as engine parts, radiators, cans, and construction materials. The lead content of this cookware is relatively low (<1000ppm by X-ray fluorescence), however significant amounts of lead, as well as aluminum and cadmium were released from many of the samples using dilute acetic acid extractions at boiling and ambient temperatures. Potential exposures to lead per serving were estimated to be as high as 260μg, indicating that such cookware can pose a serious health hazard. We conclude that lead, aluminum and cadmium can migrate from this aluminum cookware during cooking and enter food at levels exceeding recommended public health guidelines. Our results support the need to regulate lead content of materials used to manufacture these pots. Artisanal aluminum cookware may be a major contributor to lead poisoning throughout the developing world. Testing of aluminum cookware in other developing countries is warranted.

Estimated long-term dietary exposure to lead, cadmium, and mercury in young Korean children.

Controlling for day-to-day variation is a key issue in estimating long-term dietary exposure to heavy metals using 24-hour recall (24HR) data from a relatively small number of days. This study was conducted to estimate long-term dietary exposure to lead, cadmium and mercury among Korean children using the Iowa State University (ISU) method and to assess the contributions of different food groups to heavy metal intake. We analyzed 2 days of 24HR data from 457 children between 0 and 6 years of age in 2010. Using bootstrapped concentration data for 118 representative foods, 93.5% of total intake was included in the exposure estimates in this study. Using the 2-day exposure data, we estimated long-term exposure by controlling for within-individual variation using the ISU method. The long-term dietary exposure estimates (mean±standard deviation) for lead, cadmium, and mercury were 0.47±0.14, 0.38±0.20, and 0.22±0.08 μg/kg bw/day, respectively. For lead and cadmium, the percentages of children whose exposure was greater than the reference value were 35 and 42%, respectively. Fruits were an important source of lead exposure, and cereal and fish and shellfish made the greatest contributions to the total cadmium and mercury exposure. Our findings also suggest that the long-term exposure to lead and cadmium was somewhat greater than the reference values, whereas mercury exposure was well below than the reference value in this population. Further studies may be necessary to evaluate the food items contributing to heavy metal exposure, and continuous monitoring is needed to ensure the safety of food intake and dietary patterns among vulnerable groups in Korea.

Identification of environmental sources of lead exposure in Nunavut (Canada) using stable isotope analyses

BackgroundBlood lead levels (BLLs) were measured in the adult Inuit population of Nunavut, Northern Canada, during the Inuit Health Survey (IHS) in 2007–2008. Approximately 10% of the adult participants had BLL over the Health Canada's guidance of 100μg/L. Objectives1) To repeat the measurement of BLL among the IHS participants with high BLL and household members including pregnant women and children under 10years of age; 2) to measure lead (Pb) concentrations in environmental samples to identify potential sources and 3) to explore how Pb from environmental samples contributes to BLL using Pb stable isotopic analyses. MethodsBlood samples were collected from 100 adults and 56 children in 2012. A total of 169 environmental samples (tap water, house dust, paint, country food, soil, and ammunition) were collected from 14 houses from three communities where the IHS participants had the highest BLL. Total Pb concentrations and Pb isotope mass balance were determined by inductively coupled plasma-mass spectrometry (ICP-MS). ResultsThe geometric mean of BLL was 43.1μg/L; BLL increased with age and was higher in adults than children (71.1 vs. 17.5μg/L). Median Pb concentrations in water (1.9μg/L) and dust (27.1μg/m2 for wiped dust, 32.6mg/kg for vacuum dust coarse fraction, and 141.9mg/kg for vacuum dust fine fraction) were generally higher than in other parts of Canada. Median Pb concentrations of food and soil coarse and fine fractions were low (36.6μg/kg, 5.4mg/kg and 11.8mg/kg respectively); paint chips exceeded the Canadian guidelines in two houses (median: 3.8mg/kg). Discriminant analyses and isotope ratio analyses showed that ammunition and house dust are major sources of Pb in this study population. ConclusionAnalyses of Pb stable isotopes are useful to identify the routes of exposure to Pb. This approach can contribute to develop targeted public health programmes to prevent Pb exposure.

Lead exposure from backyard chicken eggs: a public health risk?

Although the USA has made significant strides in reducing lead exposure, new and emerging sources are raising cause for public concern. Recent reports of finding lead in eggs from chickens raised in urban gardens has highlighted the need to consider the potential health risks of consuming eggs from backyard chickens. Following the detection of 0.33μg/g lead in the edible portion of eggs submitted for lead analysis from a backyard chicken owner, further investigation was conducted to determine the source and extent of lead exposure in the flock. Several birds, almost two dozen eggs, and environmental samples were submitted to the California Animal Health and Food Safety Laboratory for further testing. Lead was detected in the blood, liver, kidney, and bone at varying concentrations in all birds but was not detected in the muscle tissue. All egg shells contained detectable amounts of lead, while only a little over half of the edible portion of the eggs contained lead. The detected concentrations in the edible portion approached or exceeded the recommended threshold of lead consumption per day that should not be exceeded by young children if a child consumed one average-sized egg. Peeling paint from a wooded structure adjacent to the flock's coop was the likely lead source containing 3,700μg/g lead. Thus, removal of the chickens from the source and periodic testing of eggs for lead were recommended. This case illustrates the need for consumers and health care workers to be aware of potential sources for lead exposure such as backyard chickens.

Clinical analysis of 129 children with lead poisoning

Objective To assess the distribution of blood lead levels and the sources of lead exposure in children with lead poisoning, and thus to offer recommendations for clinical diagnosis and treatment of childhood lead poisoning. Methods The clinical data of 129 patients with lead poisoning was collected and analyzed at the Out-patient Department of Lead Poisoning Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine during Sep.2012 and Aug.2013 were collected and analyzed.All children were required to fill out the outpatient questionnaire on heavy metal (including children's demographic data, growth assessment, frequency of hand-mouth behavior, and the behavior of washing hands before eating, dietary, sources of lead exposure, and the family environment, etc.). Other data of medical history, physical examinations(height, weight, growth and development) were also collected.Blood samples were collected to measure blood lead level by graphite furnace atomic absorption spectrometry. Results (1)The above 129 patients were from 14 provinces (municipalities and autonomous regions), including 64 cases in Zhejiang (49.6%), 30 cases in Shanghai (23.0%), 13 cases in Jiangsu (10.1%), 6 cases in Jiangxi (4.7%), 5 cases in Hebei (3.9%), 2 cases in Anhui and Guangdong (1.6%); and 1 case in Fujian, Henan, Hunan, Jilin, Inner Mongolia, Heilongjiang and Shandong (0.8%), respectively.(2) In the patients, the blood lead level was 17.0-892.0 μg/L[(251.5±155.8) μg/L] and the median was 235.0 μg/L.(3)The mean age of the children was 4.3 years.Fifteen cases were less than 1 year old, and the mean blood lead level was (367.8±137.7) μg/L.Thirty-seven cases were 1-3 years old children, and the mean blood lead level was (250.5±116.3) μg/L.Fifty cases were 3-6 years old children, and the mean blood lead level was (237.7±179.7) μg/L.Twenty-seven cases were over 6 years old, and the mean blood lead level was (213.9±141.8) μg/L.(4)One hundred and eleven cases of the children could find the definite sources of lead exposure, mainly from industrial pollution (35.7%) and domestic pollution (64.3%). The blood lead levels in 18 cases were less than 100 μg/L, and their definite lead pollution source was not found.(5) Most of the children had the symptoms of inattention, hyperactivity, aggressive behavior, constipation and abdominal pain, and so on.(6)Logistic regression analysis of children with blood lead levels ≥ 235.0 μg/L showed that lead pollutants and age were the main risk factors for lead poisoning. Conclusions Industrial pollution are associated with higher blood lead levels among children aged 0-6 years old(occupying one-third of the pollutants). The younger children tend to have higher blood lead levels, and the data also suggest that greater attention should be paid to children who used red powder. Key words: Lead poisoning; High-risk factors; Lead exposure; Child

0029 A Study of Blood Multi-element Concentrations in Lead-exposed and Non-exposed Workers

ObjectivesBoth lead recycling and lead-containing paint are the main source of lead exposure. During the lead industrial processes, the workers exposed to many elements including non-essential elements and essential elements....