Blood lead levels in the general population of Taiwan,Republic of China

The purpose of this study was to investigate the environmental lead exposure of the general population in Taiwan. A total of 2919 residents of Taiwan were selected by multistage sampling methods. The participants were characterized by questionnaires and 10 ml venous blood was collected for blood lead measurement. A quality assurance/quality control program was designed during the analysis of blood lead levels. The mean blood lead level of 2719 residents without occupational lead exposure was 8.29 ± 5.92 g/dl. After adjustment for age and sex distribution to the Taiwan general population, the mean blood lead level was 8.10 g/dl. Adjusted for an 11% underestimation of blood lead levels among the six laboratories, the mean blood lead level was estimated to be 8.99 g/dl. This study also found that blood lead levels were associated with personal characteristics, i.e., gender, ethnic group, education level; lifestyle factors, i.e., smoking, alcohol consumption, sources of drinking water; and residential location, i.e., levels of urbanization, distance of house from the road. However, age, floor of residence, milk consumption, betel nut consumption, and Chinese herbal drug consumption were not found to be associated with blood lead levels. These results show that blood lead levels in Taiwan residents were not higher than in most developed and developing countries. Environmental lead pollution does not seem to be a serious problem in Taiwan.     

Assessment of lead exposure and associated risk factors in urban children in Silesia, Poland

A program of childhood lead poisoning prevention was conducted in six cities of Silesia, the most industrialized region of Poland. We analyzed records of 11,877 children aged 24-84 months, tested between 1993 and 1998, to assess children's exposure to lead and associations of blood lead levels (BLL) with season of sampling, questionnaire data, and environmental levels of lead. Air lead concentrations and lead fallout, as measured in the ambient air monitoring system, were below current Polish air quality standards and gradually decreased. The geometric mean (GM) BLL was 6.3 microg/dL (range from 0.6 to 48 microg/dL), and >13% of children had BLL > or =10 microg/dL. Mean BLL declined from 6.8 microg/dL in 1993-1994 to almost 5.5 microg/dL in 1998. GM BLL in spring and summer ('nonheating' season) months were 10% higher than BLL in children tested in fall and winter ('heating' season), although air lead concentrations were lower in nonheating and higher in the heating season. For both the heating and nonheating seasons, there was a significant increase in the mean BLL with increasing air lead concentrations. Poor housing (odds ratio (OR): 1.82; 95% CI: 1.4, 2.3), two or more siblings in the family (OR: 3.12; 95% CI: 2.6, 3.7), lack of recreational trips outside the region (OR: 1.66; 95% CI: 1.47, 1.89), and the time child spent outdoors were associated with elevated BLL. Variables found to affect BLL in the Silesian children should be used to propose criteria to improve identification of children at risk and to focus prevention activities more effectively.     

Exposure to lead of the Belgian population

Summary According to the Council Directive of 29 March 1977 on biological screening of the population for lead, the blood-lead levels (PbB) were determined in samples of the Belgian population not occupationally exposed to this metal. Two campaigns of sampling were performed: the first one in 1979 (1678 samples analysed) and the second in 1981 (1000 samples analysed). Sampling was done in urban and industrial zones, as well as in areas where lead risk could be present. Concerning the urban and industrial areas, the results obtained seem to indicate that a particular lead risk does not exist for the adult population if we consider the reference levels of the CEE Directive. Moreover, the results of the second campaign of sampling showed a decreasing trend: the median PbB values dropped from 183 to 156 g/l in Brussels and from 192 to 139 g/l in Liège. This could be partly due to the limitation of the lead content of gazoline. On the other hand, the results of the surveys clearly demonstrated the existence of two areas where an obvious lead risk exists. In one of those, the lead risk is of industrial origin (lead smelter) and concerns mainly children: median PbB value 260 g/l, percentile 90 and 98 respectively 390 and 430 g/l. In the other one, the lead risk is from a hydric source and concerns adults and children: median PbB value 258 g/l, percentile 90 and 98 respectively 370 and 520 g/l.     

锌原卟啉作为环境铅污染人群筛查指标的可行性研究

目的探讨红细胞锌原卟啉（ZPP）应用于人群接触环境铅污染筛查指标的可行性。方法以紫金县某电池厂附近常住居民为调查对象,采集被调查者静脉血2～3 mL,采用血液锌原卟啉测定仪测定ZPP、石墨炉原子吸收光谱法测定血铅。儿童以血铅含量≥100μg/L、成年人以≥400μg/L为慢性铅中毒判定标准。结果共调查946名居民,其中1～13岁儿童174人、16～87岁成年人772人。儿童血铅含量超标率为14.9%（26/174）,儿童ZPP含量中位数为0.780μmol/L,血铅中位数为47.675μg/L,儿童ZPP含量与血铅含量的相关关系没有统计学意义（P〉0.05）。成人血铅含量超标率为9.5%（73/772）,成人ZPP含量中位数为0.740μmol/L,血铅中位数为69.572μg/L,成人ZPP含量与血铅含量呈弱相关关系（r=0.344,P〈0.05）。儿童血铅高水平组（血铅≥100μg/L）ZPP含量与血铅含量呈较强的相关关系（r=0.530,P〈0.05）,儿童血铅低水平组（血铅〈100μg/L）ZPP含量与血铅含量的相关关系没有统计学意义（P〉0.05）。成人血铅高水平组（血铅≥400μg/L）和低水平组（血铅〈400μg/L）的ZPP含量与血铅含量均具有相关关系（r分别为0.566、0.142,均P〈0.05）。结论成人血铅或儿童血铅水平较高时,ZPP可以作为环境铅污染人群筛查的指标。     

无锡市某私营铅蓄电池厂铅作业危害分析

目的监测与评价某私营铅蓄电池厂铅作业相关的职业病危害因素,为后续铅作业人员的个人防护和健康监护提供科学依据。方法采用现场调查方法了解该企业职业卫生管理现状,按GBZ159—2004、GBZ／T160．10～2004和GBZ2．1—2007等对工作场所中铅烟、铅尘进行检测和分析并结合职业健康检查分析影响工作人员血铅浓度的潜在因素。结果该企业存在铅烟、铅尘等职业病危害因素;铅烟、铅尘超标率为92．1％,铅作业人员血铅浓度增高比例为77．5％;铅作业人员血铅浓度与工龄、学历、下班前是否沐浴以及铅作业相关卫生知识知晓率有关（均P〈0．05）。结论该私营企业存在明显的铅作业危害,应改善工作环境,加强作业人员健康宣教及健康防护。     

Early health effects and biological monitoring in persons occupationally exposed to tetraethyl lead

Summary Dependent on the level of occupational exposure to tetraethyl lead, the occurrence of early signs of toxicity and the urinary excretion of triethyl lead, diethyl lead and total lead compounds were investigated. This was done in the following cohorts in the province of Hubei, China: 277 workers at gasoline depots exposed to gasoline, 36 traffic policemen exposed to automobile ex haust and 342 public office workers (virtually non-exposed controls). Mean external tetraethyl lead exposure concentrations were 84.8 g/m³ (as Pb) for the gasoline depot workers, 5.2 g/m³ for traffic police and 1.1 g/m³ for the controls. No significant subclin organic lead toxicity were found in the group of traffic policemen compared with the controls. In the cohort of gasoline workers, however, there was a statistical increase (vs controls) in the frequency of appearance of tremor and of sinus bradycardia. When the cohort of gasoline workers was divided into subgroups of different ranges of exposure, dose-dependence was noted. In general, the urinary excretion of triethyl lead was very low compared to that of diethyl lead, which appears to be a sensitive and specific indicator of exposure to tetraethyl lead; total lead excretion did not correlate well with actual external tetraethyl lead exposure. On the basis of these data it seems that current occupational exposure limits for tetraethyl lead are inadequate and need to be revised. In addition, a biological limit, based on urinary diethyl lead excretion, may be proposed.This paper summarizes data of a thesis (Zhang 1993) submitted to the Medical Faculty of the Heinrich-Heine-Universität Düsseldorf, in partial fulfilment of the requirements for the doctoral degree     

Lead exposure in starter battery production: investigation of the correlation between air lead and blood lead levels

The threshold limit value (TLV) for lead (in Germany, the MAK value) is based on a certain blood lead concentration (in Germany BAT value = biological tolerance value for working materials) that is not to be exceeded; thereby a statistically significant association between air lead (PbA) and blood lead (PbB) is assumed. On the basis of a 10-year period of (1982–1991) biological and ambient monitoring of 134 battery factory staff and their workplaces, a PbA/PbB correlation with the regression equation PbB = 62.183 + 21.242 × Log 10 (PbA) (n = 1089, r = 0.274, P < 0.001) was calculated. These results are in line with those of several other investigations. The shape of the regression curve and the wide scattering of values led to the assumption that PbA values above the MAK value (0.1 mg/m³) do not necessarily result in increased PbB values. Similarly, PbA values lower than the MAK value do not guarantee PbB levels below the BAT value in every case. These observations are influenced by numerous confounders and intervening variables. It is concluded that lowering MAK values as a consequence of lowering BAT values is not mandatory.     

Blood lead in the general population in Poland

Lead concentration in venous blood (Pb-B) was investigated in 1122 inhabitants (including 555 children under 10 years of age) of five Polish towns with no large industrial lead emitters (group I) and in 1246 persons (707 children under 10 years of age) living in the vicinity of zinc and copper mills (group II). The samples were analysed using electrothermal atomic absorption spectrometry (ETAAS) and the performing laboratory participated in the external quality control scheme during the study period (1992–1994). In group I the mean geometric Pb-B concentrations ranged from 23.8 to 48.3g/l in females, from 42.5 to 76.8 g/l in males and from 29.9 to 62.5 g/l in children. In group II, the mean geometric Pb-B concentrations were significantly higher and ranged from 49.4 to 105 g/l in females, from 98.5 to 149 g/l in males and from 73.7 to 114 g/l in children, the values decreasing as the distance from the source of emission increased. Cigarette smoking was found to bring about a significant increase in Pb-B levels for both males and females. A significant correlation was noted between Pb-B concentrations in mothers and children. The ratio between child and maternal Pb-B concentrations amounted to approximately 1.0 for group I and to about 0.5 for group II. These findings indicate the necessity of undertaking preventive activities over the lead-contaminated areas. However, the lead hazard in Poland seems to be associated with point sources of emission and hence does not concern the whole population.     

Assessment of exposure to lead and cadmium through biological monitoring: results of a UNEP/WHO global study

This paper describes a UNEP/WHO project on the assessment of human exposure to lead and cadmium through analysis of blood and kidneys. The following countries have participated: Belgium, India, Israel, Japan, Mexico, People's Republic of China, Peru, Sweden, United States, and Yugoslavia. No laboratory started the monitoring before achieving satisfactory results of quality control (QC) analysis (samples of cow blood spiked with lead and cadmium and freeze-dried horse kidney cortex for cadmium analysis) according to predetermined criteria based on a linear regression model. Two hundred teachers from one urban area in each country constituted the target group for lead and cadmium in blood and cases of "sudden, unexpected death" for cadmium in kidney cortex. QC samples were analyzed in parallel with the monitoring samples to assure validity of the obtained results. The quality assurance program also included preanalytical quality control. There was considerable variation in metal exposure between areas. Geometric means for lead in blood ranged from about 60 micrograms Pb/liter in Beijing and Tokyo to 225 in Mexico City. The values were below 100 micrograms Pb/liter also in Baltimore, Jerusalem, Lima, Stockholm, and Zagreb, and between 100 and 200 micrograms Pb/liter in Brussels and India. In general, males had higher blood levels than females and smokers higher than nonsmokers. With a few exceptions the values were lower than results reported in a recent study within the European Communities. Geometric means for cadmium in blood ranged from 0.5 microgram Cd/liter in Stockholm and Jerusalem to 1.2 in Brussels and Tokyo. Cadmium levels were considerably higher among smokers than among nonsmokers. Tokyo had the highest values for cadmium in kidney cortex with a geometric mean in the age group 40-60 years of 60-70 mg Cd/kg wet wt. Lowest values were found in Baltimore, Beijing, India, and Jerusalem, with means around 20-25 mg Cd/kg wet wt. There was a tendency toward higher values for smokers than for nonsmokers, but no differences related to sex. Data were not received from Mexico and Peru.     

Blood lead levels in children of S.W. Sardinia

The purpose of the present study was to make a preliminary evaluation of blood lead levels in school-aged children from three towns of southwestern Sardinia, Portoscuso, S. Antioco and Calasetta, the first of which is very close to a large industrial complex. Blood lead concentration was determined in venous blood samples by graphite furnace atomic absorption spectrophotometry. The survey revealed that children residing in the town of Portoscuso had higher mean blood lead levels (12.7 g/dl) than children of the same age residing in S. Antioco and Calasetta (8.3 and 8.4 g/ dl respectively) and that levels were slightly higher in males than in females. This difference is suggested to be a result of the greater fallout of industrial pollutants in the area of Portoscuso.Corresponding author.     

围产期铅暴露对新生大鼠血铅含量的影响

目的　了解铅通过母体对生长发育期仔代血铅的影响。方法　对不同浓度低水平铅暴露后的大鼠仔代的血铅进行测定。结果　铅可由母体经胎盘和乳汁传递给仔代。结论　胚胎期和哺乳期经胎盘和乳汁“染铅” ,是导致子代铅蓄积的重要原因。     

职业性铅暴露工人血铅和血尿酸的相关性分析

目的 研究职业性铅作业工人血铅和尿酸的变化,探讨血铅浓度变化和血尿酸指标之间的关系.方法 车间空气中铅烟的短时间接触浓度用原子吸收火焰法检测.选择一般情况可比的非铅作业工人作为对照,根据接触铅的浓度是否超过职业限值将263名铅接触工人分为职业限值内组及超职业限值组.分析不同血铅水平和血尿酸指标的变化.结果 (1)车间空气中铅烟的时间加权平均容许浓度(PC-TWA)达0.13 mg/m3,超标率为68.61％; (2)接铅超职业限值组血铅浓度达(3.16±0.03) μmol/L、尿酸为(528±109.48) μmol/L,均显著高于对照组(P＜0.05); (3)血铅浓度的变化和尿酸异常率存在一致的变化趋势.结论 职业性铅接触引起血铅浓度升高和血尿酸升高,且血铅浓度越高,血尿酸升高程度越大.     

基于IEUBK模型研究环境铅对婴儿血铅的影响

目的利用环境铅、出生前铅暴露数据和暴露吸收生物动力学模型(IEUBK模型),探讨环境铅对婴儿6月龄时血铅浓度的影响。方法利用2005-2007年的出生队列资料、出生前铅暴露数据和婴儿6月龄时血铅浓度值,以及婴儿居住环境土壤、大气和饮用水等介质中的铅检测数据,基于IEUBK模型计算环境铅引起的婴儿血铅增高水平。结果婴儿出生前就存在铅暴露,孕晚期母亲血铅浓度几何均数为(40.3±3.7)μg/L,6月龄婴儿的血铅浓度的几何均数为(54.7±6.7)μg/L,有17.3%的婴儿血铅浓度超过100μg/L。研究对象居住环境中多种介质均能检测到铅,土壤、大气和饮水中铅的几何均数浓度分别为45.57mg/kg、0.023μg/m3和3.25μg/L。根据IEUBK模型计算的由环境铅及出生前铅暴露引起的婴儿6月龄血铅浓度几何均数值为12.4μg/L,占其实际血铅浓度的22.7%。结论研究区域婴儿仍存在较高水平的血铅暴露,其居住环境内存在一定程度的铅污染现象。除环境铅外,当地婴儿可能还存在其他的铅暴露来源。     

Occupational exposure to airborne lead in Brazilian police officers

Shooting with lead-containing ammunition in indoor firing ranges is a known source of lead exposure in adults. Police officers may be at risk of lead intoxication when regular training shooting exercises are yearly mandatory to law enforcement officers. Effects on health must be documented, even when low-level elemental (inorganic) lead exposure is detected. Forty police officers (nineteen cadets and twenty-one instructors) responded to a questionnaire about health, shooting habits, and potential lead exposure before a training curse. Blood samples were collected and analyzed for blood lead level (BLL) before and after a three days training curse. The mean BLL for the instructors’ group was 5.5 μg/dL ± 0.6. The mean BLL for the cadets’ group before the training was 3.3 μg/dL ± 0.15 and after the training the main BLL was 18.2 μg/dL ± 1.5. Samples were analyzed by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). All the participants in the training curse had significantly increased BLL (mean increment about 15 μg/dL) after the three days indoor shooting season.In conclusion, occupational lead exposure in indoor firing ranges is a source of lead exposure in Brazilian police officers, and appears to be a health risk, especially when heavy weapons with lead-containing ammunition are used in indoor environments during the firing training seasons.     

Urinary lead as a possible surrogate of blood lead among workers occupationally exposed to lead

Objectives: The aim of the present study is to investigate whether lead (Pb) in urine (Pb-U) can be a valid surrogate of lead in blood (Pb-B), the traditional biomarker of exposure to lead in occupational health. Methods: Blood and spot urine samples were collected from 258 workers of both sexes occupationally exposed to lead. The samples were analyzed for lead by graphite furnace atomic absorption spectrometry, and the correlation between Pb-B and Pb-U was examined by linear regression analysis before and after logarithmic conversion. Results: The correlation coefficient (0.824; P < 0.01) was largest when the relationship between Pb-B and Pb-U was examined with 214 cases of one sex (i.e., men) after Pb-U was corrected for a specific gravity (1.016) of urine (Pb-Usg) and both Pb-B and Pb-Usg were converted to logarithms. The geometric means (GMs) of Pb-B and Pb-Usg for the 214 men were 489 μg/l and 81 μg/l, respectively. When Pb-Usg was assumed to be 100 μg/l in this set of correlations, the 95% confidence range of Pb-B for the group mean was narrow, i.e., 543–575 μg/l (with GM of 559 μg/l), whereas that for individual Pb-B values was as wide as 355–881 μg/l. Conclusions: The correlation of Pb-U with Pb-B among workers occupationally exposed to Pb was close enough to suggest that Pb-U may be a good alternative to Pb-B on a group basis, but not close enough to allow Pb-U to predict Pb-B on an individual basis. Received: 6 April 1999 / Accepted: 17 July 1999     

铅作业工人血铅、尿铅和锌原卟啉测定结果分析

目的比较铅作业工人和非铅作业工人血铅、尿铅浓度、红细胞锌原卟啉和血常规的差异,探讨铅作业工人红细胞锌原卟啉和血铅、尿铅浓度的相关性。方法以蓄电池企业的252名铅作业工人作为接铅组,电子厂205名非铅作业工人作为对照组,测定血铅、尿铅浓度、红细胞锌原卟啉和血常规,并对结果进行统计学处理。结果接铅组血红蛋白含量低于对照组(P0.05),白细胞和红细胞、血小板则无差异(P0.05),接铅组红细胞锌原卟啉、血铅、尿铅浓度均显著高于对照组(P0.01),尿铅与红细胞锌原卟啉的相关系数(r)=0.166,血铅与红细胞锌原卟啉的相关系数r=0.406。结论长期接触铅可导致血铅、尿铅浓度和红细胞锌原卟啉升高,血红蛋白降低,对白细胞、红细胞、血小板无明显影响,血铅与红细胞锌原卟啉的相关性较尿铅与红细胞锌原卟啉的相关性好。     

Plasma-lead concentration: investigations into its usefulness for biological monitoring of occupational lead exposure

BACKGROUND: The lead concentration in plasma is correlated to that in whole blood with a two to fourfold variation. It has never been investigated if this variation is inter-individual. METHODS: Lead and hemoglobin were determined in blood and plasma from 13 lead workers with a history of relatively high blood-lead concentrations, sampled three times during 1 day. The variation in the distribution of lead between cells and plasma was studied, but not the variation in the lead concentrations as such. RESULTS: Blood hemoglobin decreased with rising plasma lead (0.9-3.0 microg/L). Regarding the distribution of lead, no effect of current exposure during the day or of recent meals appeared. As much as 84% of the overall variance of the distribution of lead between cells and plasma could be attributed to individual factors. After adjustment for erythrocyte volume fraction this decreased to 67%. Plasma samples with elevated hemoglobin concentrations (due to in vitro hemolysis) had somewhat elevated lead concentrations. CONCLUSIONS: Plasma lead is not significantly altered by variation in a single day's exposure and, therefore, the choice of time of the day is not critical for sampling. However, plasma lead is negatively correlated to blood hemoglobin and mild hemolysis (not visible by the eye) in a sample may increase plasma lead with up to 30%. Finally, plasma provides lead exposure information that differs from whole blood, but it is not clear which one of these is the biomarker with the closest relation to exposure and/or effects.     

Assessment of early-life lead exposure in rural Bangladesh

Lead is a well-known neurotoxic metal and one of the most toxic chemicals in a child’s environment. The aim of this study was to assess early-life lead exposure in a pristine rural area of Bangladesh. The exposure was expected to be very low because of the absence of vehicle traffic and polluting industries. Lead was measured in erythrocytes, urine, and breast milk of 500 randomly selected pregnant women, participating in a randomized food and micronutrient supplementation trial in Matlab (MINIMat). Lead was also measured in urine of their children at 1.5 and 5 years of age, and in rice, well water, cooking pots, and materials used for walls and roof. All measurements were performed using ICPMS. We found that the women had relatively high median erythrocyte lead levels, which increased considerably from early pregnancy to late lactation (81-136 μg/kg), probably due to release from bone. Urinary lead concentrations were unchanged during pregnancy (median ∼3.5 μg/L) and non-linearly associated with maternal blood lead levels. Children, at 1.5 and 5 years of age, had a median urinary lead concentration of 4 μg/L, i.e., similar to that in their mothers. Rice, the staple food in Matlab, collected from 63 homes of the study sample, contained 1-89 μg/kg (median 13 μg/kg) dry weight and seems to be an important source of lead exposure. Other sources of exposure may be cooking pots and metal sheet roof material, which were found to release up to 380 and 4200 μg/L, respectively, into acidic solutions. Based on breast milk lead concentrations (median 1.3 μg/L) a median daily intake of 1.2 μg was estimated for 3 months old infants. However, alternatives to breast-feeding are likely to contain more lead, especially rice-based formula. To conclude, lead exposure in women and their children in a remote unpolluted area was found to be surprisingly high, which may be due to their living conditions.     

Blood lead levels in shopkeepers and car traffic pollution in Liguria,Italy

A study was conducted into the exposure to atmospheric pollution caused by car traffic by measuring blood lead (PbB) levels in a sample of 657 adult individuals (shopkeepers) all living in Liguria. The mean level of blood lead in all examined individuals was 9.39 µg dl^–1 (0.45 µmol per liter; C.I. 95%: 9.06–9.75 µg dl^–1; 0.44–0.47 µmol per liter) with a range between 2.0 and 46.03 µg dl^–1 (0.10–2.22 µmol per liter). The average Pb values in individuals working in streets with high and very high traffic was 8.30 µg dl^–1 (0.40 µmol per liter; C.I. 95%: 7.41–9.31 µg dl^–1; 0.36–0.45 µmol per liter) and 9.98 µg dl^–1 (0.48 µmol per liter; C.I. 95%: 9.62–10.37 µg dl⁰¹; 0.46–0.50 µmol per liter), respectively. These average blood lead levels were statistically greater than the average PbB values of those working in low traffic streets (7.06 µg dl^–1; 0.34 µmol per liter; C.I. 95%: 6.22–7.94 µg dl^–1; 0.30–0.38 µmol per liter).The percentile distribution (50th, 90th and 98th P) for all subgroups surveyed has always proved to be below the maximum limits specified by EC Directive No. 77/312.