An Examination of Blood Lead Levels in Thai Nielloware Workers

OBJECTIVES: The objectives of this study were to determine the lead levels in blood samples from nielloware workers, to determine airborne lead levels, to describe the workers' hygiene behaviors, and to ascertain and describe any correlations between lead levels in blood samples and lead levels in airborne samples. METHODS: Blood samples and airborne samples from 45 nielloware workers were collected from nielloware workplaces in Nakhon Sri Thammarat Province, Thailand. Lead levels were determined by flame atomic absorption spectrometry (FAAS), at a wavelength of 283.3 nm. FAAS was used especially adequate for metals at relatively high concentration levels. RESULTS: The geometric mean of the 45 airborne lead levels was 81.14 microg/m3 (range 9.0-677.2 microg/m3). The geometric mean blood lead level of the 45 workers was 16.25 microg/dL (range 4.59-39.33 microg/dL). No worker had a blood lead level > 60 microg/dL. A statistically significantly positive correlation was found between airborne lead level and blood lead levels (r = 0.747, p < 0.01). It was observed that personal hygiene was poor; workers smoked and did not wash their hands before drinking or eating. It was concluded that these behaviors had a significant correlation with blood lead levels (p < 0.001). CONCLUSION: Improvements in working conditions and occupational health education are required due to the correlation found between blood leads and airborne lead levels.

Health Effects of Air Pollution on Street Vendors: A Comparative Study in Bangkok

Traffic related air pollutants are a main concern of people living and working along the road. So far a few researches have been conducted to study the adverse health effects of traffic-related air pollutants among street vendors in Thailand. This study aimed to compare the level of traffic-related air pollutants, i.e. fine particulate (PM₂.₅), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO) and the daily respiratory and other health symptoms reported by street vendors at roadside and residential areas. A 61-day data collection panel study of the daily concentrations of traffic-related air pollutants in the two areas and daily respiratory and other health symptoms was conducted. The concentrations of air pollutants PM₂.₅, SO₂, NO₂ and CO in the roadside area were much greater than those at the residential area. In addition, 64.0% and 17.0% of 24-hr PM₂.₅ results in the roadside and residential areas respectively were above the standard of 65 mg/m\³. An adjusted odds ratio of a series of daily reported health symptoms was estimated with 95% confidence interval between the roadside and residential street vendors. The risk of roadside street vendors developing upper respiratory, lower respiratory and other health symptoms were 2.71-4.42, 3.62-7.82 and 1.54-2.80 times greater than those of residential street vendors, respectively. It is possible to conclude that these excess respiratory and other health symptoms are very likely due to traffic-related air pollutants.