Blood lead survey of children, pregnant women, professional drivers, street workers, and office workers in Trujillo, Peru

In this pilot study, conducted in summer 2002, the authors measured blood lead levels (BLLs) for 118 subjects in the city of Trujillo, Peru, where leaded gasoline is in the process of being phased out. Subjects included bus drivers, combi (minivan) drivers, street vendors, newspaper vendors, traffic police, taxi drivers, gas station attendants, children living both near and distant from gas stations, pregnant women, and office workers (controls). The highest BLLs were 9.2 microg/dl and 9.3 microg/dl from a child who lived near a gas station and from a traffic policeman, respectively; however, all BLLs were below the U.S. Centers for Disease Control and Prevention's advisory level of concern (10 microg/dl). Office workers (n = 8) and pregnant women (n = 36) had significantly lower BLLs (geometric mean +/- standard deviation = 2.1 +/- 0.7 microg/dl, p < 0.022; and 2.5 +/- 1.1 microg/dl, p < 0.008, respectively) than total traffic-exposed workers (n = 48; 3.2 +/- 1.8 microg/dl). BLLs of children living near gas stations (n = 17; 3.7 +/- 2.2 microg/dl) were marginally higher (p = 0.07) than for children not living near gas stations (n = 9; 2.9 +/- 1.1 microg/dl). The study was limited by small sample size and the fact that the data were based on a convenience sample not fully representative of the cohorts studied. Nevertheless, the authors' findings suggest that leaded gasoline use in Trujillo continues to affect BLLs in traffic-exposed populations.     

Traffic-related Occupational Exposures to PM2.5, CO,and VOCs in Trujillo,Peru

Abstract

A traffic-related exposure study was conducted among 58 workers (drivers, vendors, traffic police, and gas station attendants) and 10 office workers as controls in Trujillo, Peru, in July 2002. PM_2.5 was collected, carbon monoxide (CO) was measured, volatile organic compounds (VOCs) were sampled and analyzed. Newspaper vendors had the highest full-shift CO exposures (mean ± SD: 11.4 ± 8.9 ppm), while office workers had the lowest (2.0 ± 1.7 ppm). Bus drivers had the highest full-shift PM_2.5 exposures (161±8.9 pg/m³), while gas station attendants (64 ± 26.5 pg/m³) and office workers (65 ± 8.5 μg/m³) were the lowest. Full-shift benzene/toluene/ethylbenzene/xylene exposures (BTEX) among gas station attendants (111/254/43/214 μg/m³) were much higher than those among van and taxi drivers. Several of the traffic-related occupational exposures studied were elevated and are of occupational health concern.     

Serum Calmodulin Activity in Male Lead-exposed Workers

Abstract

Serum calmodulin (CaM) activity was studied in 75 lead exposed and 21 non-exposed male workers. The lead-exposed workers were divided into groups with low blood lead (BPb < 50 μg/dL) and high blood lead (BPb ≥ 50 μg/dL). The concentrations of lead, calcium, magnesium, copper, zinc, and free erythrocytic protoporphyrin (FEP) in blood were determined. Serum samples were heated in a water bath (100° C) for 3 minutes arid centrifuged for 15 minutes at 4° C (18,000 × g). The supernatants obtained were used to measure CaM activity. The results showed that: 1) Average blood lead concentrations in workers with both low and high levels of exposure were significantly higher than those in controls (p < 0.05). 2) Serum CaM activity in the high-exposure group (31.09 ± 7.84 μg/dL) was significantly lower than that in controls (78.11 ± 15.13 μg/dL,p < 0.05). The biological threshold of BPb inhibition of CaM activity was less than 50 μg/dL. 3) Multiple correlation analysis showed a negative dose-response relationship between BPb and CaM activity. The step wise regression procedure indicated that lead had negative, and calcium and magnesium positive, effects on serum CaM activity. The regression equation was Y = 66.1383 – 1.0857 X_l + 2.9676 X₂ + 5.2222 X₃ (Y:CaM; X_l:Pb; X₂: Ca; X₃:Mg). These results of the first such study carried out in male lead-exposed workers suggest that lead can inhibit CaM activity in humans.     

Sources and risk factors for lead exposure in indigenous children of the Peruvian Amazon,disentangling connections with oil activity

Abstract

Introduction: In the Corrientes river basin, Peruvian Amazon, lead exposure among indigenous communities was first reported in 2006. To address controversy regarding the main source of exposure, this study aimed to identify the sources and risk factors for lead exposure among children from the communities in question, and to clarify the potential relationship with oil activity.

Methods: This cross-sectional study was conducted in six communities. Participants were children aged 0–17 years and their mothers. Data collection included blood lead levels (BLLs) and hemoglobin determination, a questionnaire on risk factors and environmental sampling. We used age-stratified multivariate regression models, with generalized estimating equation to account for correlation within households.

Results: Twenty-seven percent of the children had BLLs ≧10 μg/dl. Mother’s BLLs ≧10 μg/dl, playing and chewing lead scraps, fishing ≧three times/week, and living in highly oil-exposed communities increased the risk of having BLLs ≧10 μg/dl. Lead concentrations in sediment, soil, dust, and fish samples were below reference values.

Conclusions: Mother’s BLLs ≧10 μg/dl, playing and chewing lead scraps to manufacture fishing sinkers were the most important risk factors for children’s BLLs ≧10 μg/dl. The connection with oil activity appears to be through access to metal lead from the industry’s wastes.     

Effects of Lead on the Endocrine System in Lead Smelter Workers

In this study of the effects of lead on the endocrine system, 77 secondary lead-smelter workers (i.e., 62 active and 15 retired) were compared with 26 referents. Lead concentrations were determined in plasma with inductively coupled plasma mass spectrometry (i.e., index of recent exposure), in blood with atomic absorption spectrophotometry and in fingerbone with K x-ray fluorescence technique (i.e., index of long-term exposure). In addition, pituitary hormones were determined in serum by fluoroimmunoassay and thyroid hormones and testosterone in serum were determined with radioimmunoassay. Nine lead workers and 11 referents were challenged with gonadotrophin-releasing hormone and thyrotrophin-releasing hormone, followed by measurements of stimulated pituitary hormone levels in serum. Median levels of lead in plasma were 0.14 μg/dl (range = 0.04–3.7 μg/dl) in active lead workers, 0.08 μg/dl (range = 0.05–0.4 μg/dl) in retired lead workers and 0.03 μg/dl (range = 0.02–0.04 μg/dl) in referents (1 μg/dl = 48.3 nmol/l). Corresponding blood lead concentrations were 33.2 μg/dl (range = 8.3–93.2 μg/dl), 18.6 μg/dl (range = 10.4–49.7 μg/dl) and 4.1 μg/dl (range 0.8–6.2 μg/dl), respectively. Respective bone lead levels were 21 μg/gm (range = -13 to 99 μg/gm), 55 μg/gm (range = 3–88 μg/gm) and 2 μg/gm (range = -21 to 14 μg/gm). Concentrations of basal serum hormone (i.e., free thyroid hormones, thyrotrophin, sex hormone binding globulin and testosterone) were similar in the 3 groups. There were no significant associations between the hormones mentioned herein and blood plasma, blood lead and bone lead levels. In the challenge test, stimulated follicle-stimulating hormone levels were significantly lower in lead workers (p = .014) than in referents, indicating an effect of lead at the pituitary level. Also, there was a tendency toward lower basal stimulated follicle-stimulating hormone concentrations in lead workers (p = .08). This effect, however, was not associated with blood plasma level, blood lead level, or bone lead level. In conclusion, a moderate exposure to lead was associated with only minor changes in the male endocrine function, particularly affecting the hypothalamic-pituitary axis. Given that sperm parameters were not studied, the authors could not draw conclusions about fertility consequences.     

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

Background

The 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).

Methods

We 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).

Results

The 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.

Conclusion

These 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.     

Traffic-related occupational exposures to PM2.5, CO, and VOCs in Trujillo, Peru

A traffic-related exposure study was conducted among 58 workers (drivers, vendors, traffic police, and gas station attendants) and 10 office workers as controls in Trujillo, Peru, in July 2002. PM2.5 was collected, carbon monoxide (CO) was measured, volatile organic compounds (VOCs) were sampled and analyzed. Newspaper vendors had the highest full-shift CO exposures (mean +/- SD: 11.4 +/- 8.9 ppm), while office workers had the lowest (2.0 +/- 1.7 ppm). Bus drivers had the highest full-shift PM2.5 exposures (161 +/- 8.9 microg/m3), while gas station attendants (64 +/- 26.5 microg/m3) and office workers (65 +/- 8.5 microg/m3) were the lowest. Full-shift benzene/toluene/ethylbenzene/xylene exposures (BTEX) among gas station attendants (111/254/43/214 microg/m3) were much higher than those among van and taxi drivers. Several of the traffic-related occupational exposures studied were elevated and are of occupational health concern.     

The epidemiology and surveillance of blood lead in Taiwan (R.O.C.): A report on the PRESS-BLL project

 To monitor the lead hazards in industries and to investigate the prevalence of elevated blood lead levels (BLLs) in lead-exposed workers, a lead surveillance system (PRESS-BLLs) has been established and operated in Taiwan, Republic of China, since July 1993. A cohort of lead-exposed workers who received a periodic annual health examination at 55 accredited hospital laboratories was constructed. A total of 9807 separate BLL measurements were reported to the system in 1994. The mean BLL was 15.8 μg/dl in male workers and 11.6 μg/dl in female workers. The mean BLL of lead-exposed workers was significantly (P<0.05, z-test) higher than that of the general Taiwanese population (8.6 μg/dl for males and 6.7 μg/dl for females). In addition, the BLLs of 983 (10.0%) workers exceeded the regulatory action level (40 μg/dl for males; 30 μg/dl for females). The workplaces and homes of 57% of the workers with elevated BLLs were thoroughly investigated to determine the sources of lead contamination. These actions identified the causes of elevated BLLs and set up strategies to reduce workers’ lead exposure. The establishment of this occupational lead surveillance system represents a method for monitoring of lead hazards from occupational and environmental settings to prevent lead poisoning. The information acquired from the system can help in the setting up of a priority of prevention and the development of control measures. It is also useful for further monitoring of changes in the BLLs of the lead-exposed-worker cohort. The Health Department of Taiwan can use this information to evaluate the effectiveness of current industrial hygiene practice. Subjects with elevated BLLs have been medically treated and placed on long-term follow-up for sequelae. Received: 2 September 1996/Accepted: 29 November 1996     

The Physiological Response of Animals to β-Nitronaphthalene

The effect of lead exposure on blood pressure in the modern industrial setting is controversial. In this study, we followed 67 workers in a lead-battery plant for 6–10 y, and blood pressure and blood lead levels were measured every 6 mo. Weight, height, alcohol intake, cigarette smoking, and age were recorded. Partial correlation coefficients showed that initial systolic blood pressure, age, and body mass index (i.e., weight/height squared) accounted for 25%, 30.9%, and 20.2%, respectively, of the variance in systolic blood pressure (p < .001 in all cases). Conversely, average blood lead levels (13 ± 3 tests/worker) accounted for only 0.4% of the variance (not significant). Repeated-measures analysis of variance showed a small—but significant—association between blood lead levels and systolic blood pressure. There was a negative correlation between blood lead levels and diastolic blood pressure. There were 18 men with average blood lead levels that were less than 30 μg/dl (average = 25 ± 3 μg/dl), and 32 men had levels of 40 μg/dl or more (average = 47 ± 6 μg/dl). The mean final systolic blood pressure, adjusted for age, and initial systolic blood pressure were 117 ± 13 mm Hg and 114 ± 11 mm Hg, respectively. We concluded that blood lead levels had no clinically significant effect on blood pressure in lead-battery workers. The main predictors of the follow-up systolic blood pressure were age, body mass index, and initial systolic blood-pressure measurements.     

LDL cholesterol-lowering effects of grape extract used as a dietary supplement on healthy volunteers

The aim of this study was to evaluate the effects of Eminol®, the polyphenol-rich grape extract supplement (700 mg), on cardiovascular risk and oxidant stress indicators in a sample of volunteers. A randomized, double-blind, placebo-controlled clinical trial was performed over 56 days and included 60 volunteers. Thirty volunteers took 700 mg of the grape extract, Eminol® (E), and 30 took the placebo (P). On comparison of the results, a decrease in total cholesterol (E: 213.77 ± 4.1 mg/dl and P: 245.57 ± 4.1 mg/dl; p = 0.01) and LDL cholesterol (E: 142.17 ± 3.1 mg/dl and P: 165.13 ± 3.1 mg/dl; p = 0.02) levels as well as an increase in antioxidant capacity (E: 65.63 ± 5.8 μmol TE/mg and P: 57.80 ± 7.7 μmol TE/mg; p < 0.01) and vitamin E (E: 11.46 ± 0.5 μg/ml and P: 9.06 ± 0.5 μg/ml; p = 0.018) was observed. This result indicates that the grape extract Eminol® modulated the lipid profile in terms of cardiovascular risk indicators, lowering total blood cholesterol and LDL cholesterol levels.     

Lead levels in Maryland construction workers

A cross-sectional study of unionized construction workers not currently known to be performing lead work was conducted. Participants completed an interviewer-administered questionnaire obtaining information about demographics, work history, other possible sources of lead exposure and health status (including hypertension, noise-induced hearing loss and renal disease). Blood was then obtained via venipuncture for whole blood lead level, hematocrit and free erythrocyte protoporphyrin determination. Two hundred and sixty-four Maryland construction workers had median whole blood lead determinations of 7 μg/dl and mean values of 8.0 μg/dl, with a skewed distribution ranging from 2 to 30 μg/dl. None were currently engaged in known lead work. Blood lead levels were significantly higher for the 124 who had ‘ever’ worked in demolition (8.8 μg/dl vs. 7.2 μg/dl, p = .004), and for the 79 who had ever burned paint and metal and welded on outdoor structures compared to the 48 who had done none of these activities (8.6 μg/dl vs. 6.8 μg/dl, p = .01). The 58 workers who had ever had workplace lead monitoring performed had higher lead levels (9.7 vs. 7.5 μg/dl, p = .003). Blood lead levels increased with age, and cigarette smoking. African Americans (N = 68) had higher lead levels (9.1 vs. 7.5 μg/dl, p = .01). There were only two women in the study, one with a lead level of 21 μg/dl and one, 7 μg/dl. Blood lead levels did not predict either systolic or diastolic blood pressure in this population. However, there was a significant interaction between race and lead as predictors of blood pressure, with blacks demonstrating a trend-significant correlation, and whites showing a nonsignificant but negative association. Demolition and hotwork on outdoor structures are known to cause acute episodes of lead poisoning. They also appear to cause slight but persistent increases in blood lead levels. Future workplace regulation should recognize and seek to maintain the low baseline now apparent even in urban, East Coast, construction workers. Am. J. Ind. Med. 31:188–194, 1997. © 1997 Wiley-Liss, Inc.     

Micronucleus frequency in peripheral blood lymphocytes and buccal mucosa cells of copper smelter workers,with special regard to arsenic exposure

Occupational exposure in copper smelters may produce various adverse health effects including cancer which, according to available epidemiologic data, is associated mainly with exposure to arsenic. Despite a number of well-documented studies reporting an increased risk of cancer among copper smelters workers, the data on genotoxic effects in this industry are scarce. In view of the above, an assessment of micronuclei (MN) frequency in peripheral blood lymphocytes and buccal epithelial cells from copper smelter workers was undertaken. Additionally, the clastogenic/aneugenic effect in lymphocytes was assessed with the fluorescence in situ hybridization (FISH). The study was conducted in three copper smelters in southwestern Poland. The subjects (n = 72) were enrolled among male workers at departments where As concentration in the air was up to at 80 μg/m³. Exposure was assessed by measurement of arsenic concentration in urine and toenail samples. The control group (n = 83) was recruited from healthy male individuals living in central Poland who did not report any exposure to known genotoxins. The results of our study showed a significant increase in MN frequency in peripheral blood lymphocytes and in buccal epithelial cells of smelter workers, compared to the controls (7.96 ± 4.28 vs. 3.47 ± 1.70 and 0.98 ± 0.76 vs. 0.50 ± 0.52, respectively). The FISH technique revealed the presence of clastogenic and aneugenic effects in peripheral blood lymphocytes in both groups. The clastogenic effect was slightly more pronounced in the smelter workers; however, the difference was not statistically significant. The mean arsenic concentrations in urine (total arsenic species) and in toenail samples in the exposed group were 54.04 ± 42.26 μg/l and 7.63 ± 7.24 μg/g, respectively, being significantly different from control group 11.01 ± 10.84 μg/l and 0.51 ± 0.05 μg/g. No correlation between As content in urine or toenail samples and the genotoxic effect was found under study.     

中国农村地区儿童血铅水平分析

目的 描述中国农村儿童血铅总体水平及分布特征,为改善农村铅污染状况提供依据.方法 通过计算机检索中国期刊全文数据库及相关文献追溯等途径,依照严格的入选标准收集并筛选国内1994-2008年10月公开发表的关于农村儿童血铅水平研究的文献进行分析.结果 我国农村儿童血铅均值为74.93μg/L(范围:41.14～193.54μg/L),铅中毒率为19.32%(范围:2.2%～43%).禁止含铅汽油使用后儿童血铅从87.53μg/L降至71.16μg/L(u=7.13,P<0.01),禁止含铅汽油使用前后农村儿童血铅水平均低于同时期全国儿童血铅水平.调整无铅汽油使用的影响后,北京、山东农村儿童血铅均值较高.分别为99.16和92.13μg/L;吉林、河北较低,分别为41.14和56.14μg/L;18篇文献的综合分析显示,农村儿童和城市儿童的血铅均值分别为77.90和87.24 μg/L(u=3.73,P<0.01);8篇文献的综合分析显示,农村儿童和工业区儿童血铅均值分别为70.25和80.86μg/L(u=10.00.P<0.01).结论 农村地区儿童血铅水平低于全国总体水平,低于城市和工业区儿童血铅水平,推广无铅汽油后农村儿童血铅水平有了明显改善.

Abstract：

Objective To evaluate Chinese rural children's blood lead levels (BLLs) and identify its distribution features and to provide data for policy development to the prevention of rural environmental lead pollution. Methods The papers on rural children's BLLs published from 1994 to Oct. 2008 were collected by using CNKI's (China National Knowledge Infrastructure) Chinese Journal Full-test Database and other ways. The papers which were eligible for the following criteria were reviewed:(l) BLLs measured by atomic absorption spectroscopy (graphite or others) or inductively coupled plasma-mass spectrometry; (2) strict quality control; (3) no local lead pollution sources in the areas where the screened subjects live in; (4) children aged from 0 to 14 years old; (5)sample size more than 40. Results Analysis on the included 32 papers indicated that, the mean BLLs of Chinese rural children between 1994 and 2008 was 74.93μg/L (range:41.14-193.54 μg/L)and 19.32%(range:2.2%-43%) of the subjects had BLLs higher than 100 μg/L. The rural children's BLLs changed from 87.53 μg/Lto 71.16 μg/L after the use of lead free gasoline in 2000 in China, which were both lower than the general children's BBLs before 2000 and after 2001. The children in Beijing city and Shandong province showed the highest mean BLLs , with 99.16 μg/L and 92.13 μg/L respectively; while the children in Jilin province and Hebei province showed the lowest levels, with 41.14 μg/L and 56.14 μg/L respectively. The comprehensive analysis of 18 papers indicated that the mean BLLs in rural areas and urban areas were 77.90 μg/L and 87.24μg/L respectively (u=3.73, P<0.01 ). The comprehensive analysis of 8 papers indicated that the mean BLLs in rural areas and industrial areas were 70.25 μg/Land 80.86 μg/L respectively(u=10.00,P<0.01). Conclusion The BLLs of rural children in China are lower than the general levels of children in China, and also lower than urban areas and industrial areas. Promoting lead free gasoline can make a considerable decrease in the blood lead levels of rural children.     

Lead Exposure and Blood Pressure among Workers in Diverse Industrial Plants in Kenya

The study evaluated airborne exposures and blood lead (BPb) levels in 233 production workers at six diverse industrial plants in Kenya. Blood and personal breathing zone air samples were collected and analyzed for lead (Pb) using atomic absorption spectroscopy. Blood pressure (BP) levels were measured using a standard mercury sphygmomanometer. The results indicated mean airborne Pb levels ± standard deviation (SD) as follows: 183.2 ± 53.6 μg/m³ in battery recycling, 133.5 ± 39.6 μg/m³ in battery manufacturing, 126.2 ± 39.9 μg/m³ in scrap metal welding, 76.3 ± 33.2 μg/m³ in paint manufacturing, 27.3 ± 12.1 μg/m³ in a leather manufacturing, and 5.5 ± 3.6 μg/m³ in a pharmaceutical plant. The mean airborne Pb levels exceeded the U.S. Occupational Safety and Health Administration (OSHA) 8-hr time-weighted average (TWA) permissible exposure limit (PEL) for Pb of 50 μg/m³ in the battery manufacturing, battery recycling, welding, and paint manufacturing plants. Similarly, mean BPb concentrations exceeded the American Conference of Governmental Industrial Hygienists (ACGIH®) biological exposure index (BEI) for Pb of 30 μg/dl. A significant positive association was observed between BPb and breathing zone air Pb (R² = 0.73, P < 0.001). Approximately 30% of the production workers (N = 233) were in the hypertensive range with an average systolic and diastolic blood pressure (BP) of 134.7 ± 12.7 mmHg and 86.4 ± 8.9 mmHg, respectively. In the multivariate regression analysis, age, duration of work, airborne Pb and BPb levels were significantly associated (P < 0.05) with a change in BP. We recommend improved engineering controls, work practices, and personal hygiene to reduce Pb exposures. In addition, workers should undergo comprehensive medical surveillance to include BPb and BP testing, and airborne Pb assessments in all industries with significant lead exposures.     

Blood lead levels and associated sociodemographic factors among preschool children in the South Eastern region of China

Children are especially vulnerable to lead toxicity, and exposure to lead has been linked to poor school performance and delinquency in children and adolescents. Even low-level lead exposure [blood lead level (BLL) <10 μg/dL] can cause intellectual deficit. In China, BLLs in children decreased slightly after the phasing out of lead in gasoline, but few studies have examined the sociodemographic factors associated with BLL above 10 μg/dL. In this study, we sought to examine the hypothesis that sociodemographic factors predict BLLs. We measured BLLs of 1344 preschool children (3-5 years old) from the China Jintan Child Cohort Study. Children's sociodemographic and health statuses, as well as parental sociodemographic data, were collected using questionnaires. Regression models were used to explore the association between sociodemographic factors and log-transformed BLLs as well as the relationship between sociodemographic factors and the risk of BLL ≥10 μg/dL. We found the median BLL to be 6.2 μg/dL (range: 1.8-32.0 μg/dL); 8% of children had BLLs ≥10 μg/dL. Boys had a higher median BLL (6.4 μg/dL) than girls and were more likely to have BLL ≥10 μg/dL [odds ratio = 1.77, 95% confidence interval 1.14, 2.74]. BLLs increased as children aged, with a median BLL of 6.6 μg/dL among 5-year-old children. Children with siblings had a higher average BLL and greater prevalence of a BLL ≥10 μg/dL than those without siblings. Living in a crowded neighbourhood was also associated with increased BLLs. Mother's lower education, father's occupation (as professional worker) and parental smoking at home were associated with increased BLLs. This study shows that children in this area still have relatively high BLLs even after the phasing out of leaded gasoline. Both children's and parental factors and community condition are associated with increased BLLs. Future efforts are needed to identify other sources of exposure and develop targeted prevention strategies.     

Maternal nutritional status during pregnancy and surma use determine cord lead levels in Karachi, Pakistan

Objectives

To estimate the umbilical cord blood lead levels (BLLs) of Pakistani neonates and to identify determinants for umbilical BLLs.

Methods

We conducted a cross-sectional study of mothers and infants at one of the two obstetric units of two tertiary care hospitals in Karachi during January-August 2005. Information from 540 mothers selected randomly from those registered for delivery was obtained about their pregnancy, diet, and current and past lead exposures. We collected umbilical cord blood for lead levels analyzed using graphite furnace atomic absorption spectrophotometry. We computed geometric and arithmetic means. We performed multiple linear regression analysis to identify factors associated with log-transformed umbilical cord BLLs. We also performed logistic regression analysis to identify determinants of high lead cord BLLs (?10 μg/dl).

Results

The geometric mean cord BLL of the neonates was 9.6 μg/dl; arithmetic mean (S.D.) was 10.8 μg/dl (5.7) with a median of 9.7 μg/dl and a range of 1.8-48.9 μg/dl. Women who reported intake of less than 58.5 mg of elemental iron supplement per day during pregnancy had cord BLL of 10.0 μg/dl; in comparison those women who had higher iron intake had lower cord BLL (8.4 μg/dl). Those who used surma (an eye cosmetic) daily had higher cord BLL (11.5 μg/dl) as compared to those who used it less frequently (9.4 μg/dl). In multivariable linear regression model, higher iron intake, owning a car, and being in 2nd quartile of mid-arm circumference were associated with low lead levels while father's occupation in lead-based industry was associated with significantly higher umbilical cord BLLs. There was interaction of daily surma use and ethnicity. Geometric mean BLLs were varied among surma users by ethnicity.

Conclusions

Umbilical cord BLLs are high in Karachi, Pakistan, in comparison to those in developed countries such as United States. Measures are needed to reduce fetal lead exposure to prevent adverse affect on neurocognitive development. Association of low iron (below RDA of 60 mg per day) with high umbilical cord has implications for strengthening iron supplement intake during pregnancy. Umbilical cord BLLs differed among surma users by ethnicity.     

Relative bioavailability in adults of iron from a soybean product intended for complementary feeding of infants

The relative bioavailability of iron sulphate added to a soybean product intended for use as a fortified product for complementary feeding of infants was determined. Ten adults received 100mg elemental iron in an aqueous Fe(II)-sulphate solution and 1 week later 100 mg elemental iron mixed into 30 g soybean milk powder. Plasma iron concentrations were measured before, and 1, 2, 4, 6, 8 and 10 h after consumption. The area under the concentration/time curve (AUC+), the peak plasma level (t_max) and the relative bioavailability were determined. The peak of the plasma iron level after receiving 100 mg of iron solution was 176.71 ± 39.05 μg/dl at t_max = 2.8 ± 1.03h while it was 139.82 ± 34.47 μg/dl at t_max = 2.4 ± 1.3 h after consuming 30 g of soybean milk product mixed with 100mg iron solution. The relative bioavailability of iron in the soybean product was 45.8% compared to iron solution. Based on these results it is suggested that the soybean product should be fortified with 10 mg/100 g product of iron sulphate to provide 30% of the iron RDA for infants.     

Blood lead levels in the adult Victorian population: results from the Victorian Health Monitor

Objective : To estimate blood lead levels (BLLs) in the adult Victorian population and compare the distribution of BLLs with the current national reference level to better inform public health prevention and management of lead toxicity. Methods : Population‐based cross‐sectional health measurement survey of 50 randomly selected Census Collection Districts (CDs) throughout Victoria. The Victorian Health Monitor (VHM) was conducted over 12 months from May 2009 to April 2010. One eligible person (aged 18–75 years) from each household selected within each CD was randomly selected to participate. Persons with an intellectual disability and pregnant women were excluded from the sampling frame. BLLs were obtained from 3,622 of the 3,653 (99%) VHM participants. Results : The geometric mean and median BLLs from the adult sample were 0.070 μmol/L (95%CI, 0.068–0.073) and 0.05 μmol/L (range: 0.05 to 1.22 μmol/L), respectively. Elevated BLLs (≥0.483 μmol/L or ≥10 μg/dL) were identified in 19 participants (0.7%; 95%CI, 0.3–1.6). Additionally, 86 participants (1.8%; 95%CI, 1.3–2.4) were identified with BLLs between 0.242 and <0.483 μmol/L (5 to <10 μg/dL). The geometric mean BLL was significantly higher for males, compared with females (0.077 μmol/L vs 0.064 μmol/L; p<0.001). BLLs increased significantly with age for both sexes. Conclusions : The first population estimates of BLLs in Victorian adults indicate the average adult BLL to be well below the current national reference level. However, some groups of the population have BLLs at which adverse effects may occur. Implications : The results provide baseline estimates for future population health surveillance and comparison with studies of at‐risk groups.     

Pollution in Lucknow City and its health implication on exposed vendors, drivers and traffic policemen

In this pilot study, an exposure–response assessment (aged 16 to 60 years, n?=?1,012) was carried out related to eye problems due to vehicular fumes during the winter of 2003. Inhalable particles <PM₁₀ and Pb level were monitored at 12 locations of Lucknow using a Respirable Dust Sampler and EPM 2000 filter. The range of PM₁₀ particles varied from 144 to 305, 211–366 and 141–242 μg/m³ while Pb levels were 0.02–0.93, 0.06–0.90 and 0.07–0.77 μg/m³ during 2002, 2003 and 2004, respectively. The concentrations of PM₁₀ exceeded alarmingly the prescribed standards by a factor of 1.3–3.2. A health survey demonstrated that symptoms were developed such as burning of eyes (in 20 % of drivers, 74.07 % of vendors and 77.47 % of traffic policemen), eye watering (in 51.45 % of drivers, 44 % of vendors and 72.77 % of traffic policemen), constant irritation and redness (in 33.49 % of drivers, 21.29 % of vendors and 26.12 % of traffic policemen) and impaired vision (in 25.01 % of drivers, 20.37 % of vendors and 23.5 % of traffic policemen). The main finding was the prevalence of symptoms of the eyes among the population exposed to automobile fumes.     

Delayed and Competitively Inhibited Excretion of Urinary Hippuric Acid in Field Workers Coexposed to Toluene,Ethyl Benzene,and Xylene

The purpose of this study was to investigate whether the metabolic suppression of hippuric acid (HA) occurs in field workers coexposed to toluene, xylene and ethyl benzene. Eleven male spray painters were recruited into this study and monitored for 2 weeks using a repeated-measures study design. The sampling was conducted for 3 consecutive working days each week. Toluene, ethyl benzene, and xylene in the air were collected using 3M 3500 organic vapor monitors. Urine samples were collected before and after work shift, and urinary HA, methyl hippuric acid, mandelic acid, and phenylgloxylic acid concentrations were determined. In the first week, toluene concentrations were 2.66 ± 0.95 (mean ± SE) ppm, whereas ethyl benzene and xylene concentrations were 27.84 ± 3.61 and 72.63 ± 13.37 ppm, respectively, for all subjects. Pre–work shift HA concentrations were 230.23 ± 37.31 mg/g creatinine, whereas pre–work shift HA concentrations were 137.81 ± 14.15 mg/g creatinine. Mean urinary HA concentration was significantly greater in the pre–work shift samples than in the pre–work shift samples (p = 0.043). In the second week, toluene concentrations were much lower (0.28 ppm), whereas ethyl benzene and xylene were 47.12 ± 8.98 and 23.88 ± 4.09 ppm, respectively, for all subjects. Pre–work shift HA concentrations were 351.98 ± 116.23 mg/g creatinine, whereas pre–work shift HA concentrations were 951.82 ± 116.23 mg/g creatinine. Mean urinary HA concentration was significantly greater in the pre–work shift samples than in the pre–work shift samples (p <0.01); a significant correlation (r = 0.565; p = 0.002) was found between pre–work shift urinary HA levels and ethyl benzene exposure. This study showed that urinary HA peak was delayed to next morning for workers coexposed to toluene, ethyl benzene, and xylene; xylene and ethyl benzene probably played competitive inhibitors for metabolism of toluene. The study also presumed that urinary HA became the major metabolite of ethyl benzene at the end of work shift, when the exposure concentrations of ethyl benzene were 2.0 times those of xylene.