The reference value of blood lead level among the general adult population of eastern Iran.

The aim of this study to the estimate the lead concentrations in the blood of the adult population in South Khorasan Province, evaluate factors related to high lead blood concentrations and establish lead reference values (RVs) in our study population. In cross-sectional study, 400 people who lived in the province of South Khorasan in 2017 were selected. Demographic information was collected and clinical examinations were performed. As the geometric means, blood lead concentration (BLC) was expressed, 10th, 50th, 90th, and 95th percentiles, and 95% confidence intervals (CI) of the 95th percentile. The upper limits rounded values of the 95% CI with the 95th percentile were applied to calculate RVs. Mean BLC was 6.02 ± 7.41 µg dL-1, median of BLC was 4.4 µg dL-1 (IQR: 2.9-6.5; range 0.9-54.7 µg dL-1). One hundred and twenty-five (31.2%) participants had BLCs between 5 and 10.0 µg dL-1, 40 (10.0%) between 10 and 20.0 µg dL-1, and 15 (3.8%%) over 20 µg dL-1. The RVs for BLC for men and women were 16 [95% CI: 10.13-15.96] µg dL-1 and 15 [95% CI: 9.81-14.45] µg dL-1, respectively. Higher BLCs were significantly associated with age, gender, hemoglobin, white blood cell count, and serum phosphorus concentration. This bio-monitoring study of BLCs in the general population of South Khorasan Province offers important demographic and lifestyle factors-stratified reference data. It is essential to continue efforts to reduce lead exposure.

Comparison of serum concentrations of essential and toxic elements between cigarette smokers and non-smokers.

The habit of smoking remains a severe public health problem. Heavy metals in cigarettes and mainstream smoke have been extensively investigated. This study has attempted to determine the essential and toxic elements in a biological sample of smokers and non-smokers. In this case-control study, 100 smokers were compared with 100 age- and gender-matched non-smoker healthy subjects. The smoker group was selected via the snowball sampling method. Serum concentrations of trace elements were determined using ICP-MS (Agilent 7900) for subsequent analysis. Data were analyzed by SPSS software using t test or Mann-Whitney U test along with chi-square test at the significant level of less than 0.05. The results of this study indicated that subjects in the smoker group compared with non-smokers had a significantly higher median of manganese (Mn) (11.5 [5.7-17.2] versus 6 [4-12.5] (µg/L), p = 0.003), copper (Cu) (40 [34-47.2] versus 34 [29-42] (µg/L), p = 0.005), arsenic (As) (39 [9-49.2] versus 12 [5-42] (µg/L), p = 0.007), thallium (Tl) (0.54 [0.27-0.68] versus 0.34 [0.11-0.66] (µg/L), p = 0.04), and lower iron (Fe) concentration (218 [156-508] versus 429 [192-573] (µg/L), p = 0.03). This study found that the concentrations of Mn, Cu, As, and TI in cigarette smokers were significantly higher than those obtained from the control group. These results can provide health policymakers with the necessary information to take public health measures towards preventive interventions in the community, though further studies are still warranted.