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 in children of construction workers.

OBJECTIVES: This study examined whether children of lead-exposed construction workers had higher blood lead levels than neighborhood control children. METHODS: Twenty-nine construction workers were identified from the New Jersey Adult Blood Lead Epidemiology and Surveillance (ABLES) registry. Eighteen control families were referred by workers. Venous blood samples were collected from 50 children (31 exposed, 19 control subjects) under age 6. RESULTS: Twenty-six percent of workers children had blood lead levels at or over the Centers for Disease Control and Prevention action level of 0.48 mumol/L (10 micrograms/dL), compared with 5% of control children (unadjusted odds ratio = 6.1; 95% confidence interval = 0.9, 147.2). CONCLUSIONS: Children of construction workers may be at risk for excessive lead exposure. Health care providers should assess parental occupation as a possible pathway for lead exposure of young children.     

Elevated blood lead levels among children living in a fishing community, Karachi, Pakistan

Lead is a widespread environmental contaminant worldwide and is associated with adverse outcomes in children, including impaired neurobehavioral development and learning difficulties. A cross-sectional survey of 53 young children was conducted in a fishing village on an island adjacent to Karachi, Pakistan. Whole blood from each individual was tested for lead levels. Also tested were samples of cooked food, house dust, and drinking water from 36 households. Laboratory determinations were made by the Pakistan Council for Scientific and Industrial Research with quality control by the United States Centers for Disease Control and Prevention. Fifty-two subjects (98%) had blood lead levels above 10 microg/dl (mean 21.60 microg/dl), an internationally recognized threshold for potential neurotoxicity. The mean concentration was 3.90 microg/g in cooked food, 4.02 microg/l in drinking water, and 91.30 microg/g in house dust. These findings indicate possible major health concerns and suggest significant environmental contamination in this community as well as the need to identify locally relevant early childhood exposures.     

Children's blood lead levels in the lead smelting town of Port Pirie, South Australia

This survey included 1,239 children, representing 50% of the elementary school population of the lead smelting town of Port Pirie. Of these children, 7% had a capillary blood lead level equal to or greater than 30 micrograms/dl, which is the Australian National Health and Medical Research Council's "level of concern." There was a statistically significant difference in capillary lead levels by area of residence that was independent of age, sex, soil lead, rainwater tank lead, and school attended. A case-control study indicated that the following subset of factors was most predictive of an elevated blood lead level: household members who worked with lead in their occupations; living in a house with flaking paint on the outside walls; biting finger nails; eating lunch at home on school days; when at school, appearing to have relatively dirty clothing; when at school, appearing to have relatively dirty hands; and living on a household block with a large area of exposed dirt. A program to reduce the risk of elevated blood lead levels in Port Pirie children has been introduced.     

Blood lead levels in children, China

To evaluate Chinese children's blood lead levels (BLLs) and identify its distribution features, we collected articles on children's BLLs published from 1994 to March 2004 using the Chinese Biomedical Disc and reviewed 32 articles eligible for the following criteria: (1) BLLs measured by Graphite Furnace Atomic Absorption Spectroscopy or Inductively Coupled Plasma-Mass Spectrometry; (2) strict quality control; (3) no lead pollution sources in the areas where the screened subjects live; and (4) sample size bigger than 100. We found that mean BLLs of Chinese children was 92.9 microg/L (37.2-254.2 microg/L), and 33.8% (9.6-80.5%) of the subjects had BLLs higher than 100 microg/L. Nine of the 27 provinces or cities reported had average BLLs 100 microg/L. Boys' BLL was 96.4 microg/L, significantly higher than girls' 89.4 microg/L (P<0.001). BLLs of children 6 years increased with age. The mean BLLs of children living in industrial and urban areas were significantly higher than those of children in suburbs and rural areas. Our results suggested that children's BLLs in China are higher than those of their counterparts in other countries due to its heavy lead pollution. Therefore, this is of great public health importance.     

Elevated levels of blood lead in alcoholic liver disease

Summary In order to investigate the effect of alcohol intake on the activity of erythrocyte aminolevulinate dehydratase (ALA-D), serum alcohol concentration and ALA-D activity was determined in 4 groups of patients. Group I: 18 chronic alcoholics (active phase). Group II: 14 chronic alcoholics (inactive phase). Group III: 13 chronic alcoholics suffering from a biopsy verified liver cirrhosis. Group IV: 16 non-alcoholic patients with biopsy verified liver cirrhosis. Blood lead concentration was determined in patients from group III and IV.ALA-D values were found to be within the normal range in patients from group I, II and IV. 8 patients from group III had abnormally low ALA-D values and 4 of these had elevated blood lead values. Data from group III and IV yields a significant (P < 0.001) negative correlation between blood lead and ALA-D values. No correlation could be demonstrated between serum alcohol and ALA-D values from group I and III.It is suggested that patients suffering from liver cirrhosis may accumulate lead at an increased rate and that alcohol intake in these patients may cause a release of lead from the liver to the blood and thereby a depression of ALA-D activity.     

Elevated blood lead levels in refugee children--New Hampshire, 2003-2004

As a result of reductions in lead hazards and improved screening practices, blood lead levels (BLLs) in children aged 1-5 years are decreasing in the United States. However, the risk for elevated BLLs (> or =10 microg/dL) remains high for certain populations, including refugees. After the death of a Sudanese refugee child from lead poisoning in New Hampshire in 2000, the New Hampshire Department of Health and Human Services (NHDHHS) developed lead testing guidelines to screen and monitor refugee children. These guidelines recommend 1) capillary blood lead testing for refugee children aged 6 months-15 years within 3 months after arrival in New Hampshire, 2) follow-up venous testing of children aged <6 years within 3-6 months after initial screening, and 3) notation of refugee status on laboratory slips for first tests. In 2004, routine laboratory telephone reports of elevated BLLs to the New Hampshire Childhood Lead Poisoning Prevention Program (NHCLPPP) called attention to a pattern of elevated BLLs among refugee children. To develop prevention strategies, NHDHHS analyzed NHCLPPP and Manchester Health Department (MHD) data, focusing on the 37 African refugee children with elevated BLLs on follow-up for whom complete data were available. This report describes the results of that analysis, which indicated that 1) follow-up blood lead testing is useful to identify lead exposure that occurs after resettlement and 2) refugee children in New Hampshire older than those routinely tested might have elevated BLLs. Refugee children in all states should be tested for lead poisoning on arrival and several months after initial screening to assess exposure after resettlement.     

Elevated blood lead levels among adults in Massachusetts, 1991-1995

OBJECTIVE: Lead poisoning, the oldest recognized occupational disease, remains a danger for children and adults. Data collected for 664 cases reported to the Massachusetts Occupational Lead Registry in 1991-1995 were summarized in a 1998 state report. Here, the authors present some of the key findings from that report for a wider audience. METHODS: The authors summarize key findings of the 1998 state report. FINDINGS: Construction workers, in particular licensed deleaders and house painters, accounted for almost 70% of occupational cases involving blood lead levels > or = 40 micrograms of lead per deciliter (mcg/dl) of blood. Among 100 workers with the highest blood lead levels (> or = 60 mcg/dl), 29% were house painters. Hispanic workers were over-represented in the Registry. A small proportion of cases were non-occupational, typically associated with recreational use of firing ranges or do-it-yourself home renovations. CONCLUSION: Lead poisoning is a preventable disease, yet these data indicate that additional prevention efforts are warranted.     

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.     

Elevated blood lead and erythrocyte protoporphyrin levels of children near a battery-recycling plant in Haina, Dominican Republic

A survey of children from a community adjacent to an auto-battery-recycling smelter in Haina, the Dominican Republic, revealed alarming elevations of blood lead (B-Pb) and erythrocyte protoporphyrin (EP-ZnPP) compared with controls. The authors recommend follow-up confirmation and treatment of severely lead-poisoned children, shutdown of the plant, controlled disposal of the hazardous waste from the site, and relocation of the community.     

Declining blood lead levels in Victorian children

Abstract: To investigate the distribution of blood lead levels in a sample of Victorian children, and to compare current levels with those from a similar survey in 1979, blood was tested for lead in 252 children (123 under five years) attending Royal Children's Hospital as outpatients and having venepuncture blood samples for medical reasons. Blood lead levels were determined by graphite furnace atomic absorption spectrophotometer. The mean blood lead level was 0.26 μmol/L (5.4 μg/dL). In the under-five age group, the mean was 0.28 μmol/L (5.7 μg/dL). Only 1.6 per cent of this group exceeded the National Health and Medical Research Council action level of 0.72 μmol/L (15 μg/dL). Levels in this age group have declined significantly since 1979, when the mean was 0.54 μmol/L (11.1 μg/dL) and 12.9 per cent exceeded 0.72 μmol/L (15 μg/dL). Average blood lead levels have halved since 1979, with likely contributing factors being reduced exposure from lead in diet, reduced access to lead in paint and reduced lead in ambient air. Children with elevated levels had identifiable risk factors such as pica or exposure to lead-based paint, suggesting the need for ongoing public health action to prevent exposure in these groups.     

Air and blood lead levels in lead acid battery recycling and manufacturing plants in Kenya

The concentration of airborne and blood lead (Pb) was assessed in a Pb acid battery recycling plant and in a Pb acid battery manufacturing plant in Kenya. In the recycling plant, full-shift area samples taken across 5 days in several production sections showed a mean value ± standard deviation (SD) of 427 ± 124 μg/m(3), while area samples in the office area had a mean ± SD of 59.2 ± 22.7 μg/m(3). In the battery manufacturing plant, full-shift area samples taken across 5 days in several production areas showed a mean value ± SD of 349 ± 107 μg/m(3), while area samples in the office area had a mean ± SD of 55.2 ± 33.2 μg/m(3). All these mean values exceed the U.S. Occupational Safety and Health Administration's permissible exposure limit of 50 μg/m(3) as an 8-hr time-weighted average. In the battery recycling plant, production workers had a mean blood Pb level ± SD of 62.2 ± 12.7 μg/dL, and office workers had a mean blood Pb level ± SD of 43.4 ± 6.6 μg/dL. In the battery manufacturing plant, production workers had a mean blood Pb level ± SD of 59.5 ± 10.1 μg/dL, and office workers had a mean blood Pb level ± SD of 41.6 ± 7.4 μg/dL. All the measured blood Pb levels exceeded 30 μg/dL, which is the maximum blood Pb level recommended by the ACGIH(?). Observations made in these facilities revealed numerous sources of Pb exposure due to inadequacies in engineering controls, work practices, respirator use, and personal hygiene.     

Elevated blood lead levels in a riverside population in the Brazilian Amazon

Lead (Pb) is recognized as one of the most toxic metals. Sources of Pb exposure have been widely documented in North America, and the removal of Pb additives from gasoline was reflected in a dramatic lowering of blood Pb concentration. In Latin America, the removal of Pb from gasoline resulted in decreased exposure, but Pb levels in many areas remain high due to occupational and environmental sources of exposure. While many of the Pb sources have been identified (mining, industries, battery recycling, lead-based paint, ceramics), new ones occasionally crop up. Here we report on blood Pb (B-Pb) levels in remote riverside communities of the Brazilian Amazon. Blood Pb (B-Pb) levels were determined in 448 persons from 12 villages of the Lower Tapajós River Basin, Pará, Brazil. Socio-demographic and dietary information, as well as occupational, residential and medical history was collected using an interview-administered questionnaire. B-Pb, measured by ICP-MS, showed elevated concentrations. Mean B-Pb was 13.1 μg/dL±8.5, median B-Pb was 11.2 μg/dL and ranged from 0.59 to 48.3 μg/dL. Men had higher B-Pb compared to women (median: 15.3 μg/dL vs 7.9 μg/dL respectively). B-Pb increased with age for women, while it decreased for men. For both genders, B-Pb decreased with education. There were significant differences between villages. Exploratory analyses, using linear partition models, showed that for men B-Pb was lower among those who were involved in cattle-raising, and higher among those who hunted, farmed and fished. The distribution profile of B-Pb directed us towards artisanal transformation of manioc to flour (farinha), which requires heating in a large metal pan, with stirring primarily done by young men. In the village with the highest B-Pb, analysis of Pb concentrations (dry weight) of manioc (prior to transformation) and farinha (following transformation) from 6 houses showed a tenfold increase in Pb concentration (mean: 0.017±0.016 to 0.19±0.10 μg/g). This was confirmed in one of these villages where we sampled manioc paste (just before roasting) and the roasted farinha (0.05 μg/g vs 0.20 μg/g). While there may be other sources (ammunition, sinkers for fishing nets), the high concentrations in farinha, a dietary staple, assuredly makes an important contribution. Further action needs to reduce Pb sources in this region.     

儿童血铅含量调查分析

目的 筛查儿童血铅水平,能及早发现儿童铅中毒,可达到预防、提早干预和治疗的目的 ,提高本地区儿童的健康水平.方法 对2168名12岁以内儿童的血铅筛查资料进行了归纳、分析.结果 2168例儿童当中血铅≥200 μg/L(0.97 μmol/L)的儿童共159名,占总检查人数的7.33%,均为轻到中度中毒,且多表现不典型.多数患儿能找出铅接触危险因素,中毒程度与多重危险因素相关.惠儿均给予去除铅接触危险因素、营养指导等处理,2～3个月后复查血铅,其血铅水平均有不同程度下降.结论 儿童铅中毒是完全可以预防的,通过环境干预、开展健康教育、有重点的筛查和监测等措施,可以预防和早发现、早干预儿童铅中毒.     

2007-2011年中国儿童血铅水平及铅中毒率的分析

摘要:目的　描述2007-2011年我国儿童整体血铅水平、铅中毒率及分布特征。方法　本研究通过计算机检索2007-2012年公开发表的关于儿童血铅水平和（或）铅中毒率研究的论文,依照时间挑选出2007-2011年的文献按年份分类整理。对27省（市）88万多人做了调查研究。结果　2007-2011年我国儿童血铅水平（μg/L）分别是:68.62、59.13、53.36、66.56和46.56,平均血铅水平58.88 μg/L;而相应的儿童铅中毒率（%）分别是:19.56、11.56、12.67、10.41和7.27,平均铅中毒率是12.29%。结果说明,2007-2011年我国0～5岁儿童的血铅水平和铅中毒率随着年龄的增加而升高,尽管6岁组与5岁组相比,血铅水平及铅中毒率有所降低,但仍高于其他年龄组;同样,除2010年的儿童血铅水平比2008和2009年有所增加外,2007-2011年儿童血铅水平和铅中毒率随着年份的增加呈降低趋势。此外,经Meta分析发现,2007-2011年儿童铅中毒率和血铅水平也呈现明显的性别分布特征和地区分布特征。结论　2007-2011年我国儿童血铅水平和铅中毒率仍然较高,预防儿童铅中毒仍然是我国今后应当重视的医学问题和社会问题。     

铅对儿童甲状腺功能影响的研究

【目的】本文主要探讨铅中毒对儿童甲状腺功能的影响。【方法】入选对象为0~6岁的儿童,血铅采用钨舟原子吸收光谱法测定,并根据血铅的水平<100μg/L,100~200μg/L,200~499μg/L将儿童分为正常血铅组、轻度铅中毒组和中度铅中毒组。对三组对象均采用化学发光免疫技术,分别测其TT3、TT4、FT3、FT4、TSH共5项甲状腺功能指标,并计算出FT4/TSH的比值,将三组甲状腺功能指标和FT4/TSH的比值进行方差分析。【结果】正常血铅组、轻度铅中毒组和中度铅中毒组TT3、TT4、FT3、FT4值差异均无显著性,而三组的TSH值,FT4/TSH比值存在显著性差异。【结论】虽然未达到甲状腺功能低下的程度,但是轻中度铅中毒对儿童甲状腺功能已存在影响;并且随着血中铅浓度的增高,甲状腺功能损害的程度也会加重。