The Bioavailability of Lead Dust from the Lead Battery Plant

• Main Authors: Hsin-Ni Hsieh, 謝欣霓
• Other Authors: Yaw-Huei Hwang
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/88212324857711843823

碩士 === 國立臺灣大學 === 職業醫學與工業衛生研究所 === 88 === In order to find out the contribution of lead uptake through ingestion, this study was conducted to characterize the physicochemical properties and estimate the relative bioavailability of lead dust from a lead battery plant. In part I, the physicochemical properties of lead powder, and precipitated lead dust of plate manipulating and plate-cutting operations were characterized, including particulate surface, weight distribution, size distribution, components, and the lead percentage in weight. In part II, a living animal model with male Sprague-Dawley rats, 6-7 weeks old, was performed. The lead exposure group was fed with the mixture of AIN-76 semipurified diet and cathode lead dust, smaller than 106 um and precipitated during plate manipulating operation. The lead control group was fed with the mixture of AIN-76 semipurified diet and lead acetate. The target doses were 5 mg Pb/kg BW/Day and 10 mg Pb/kg BW/day. Study animals were sacrificed at the 15th, 29th, and 43th days, respectively. Blood samples were collected for lead determination to estimate the relative bioavailability of lead dust. Results of part I study showed that the surface of lead powder material was smoother than the precipitated lead dust of plate-manipulating and plate-cutting operations. For weight distribution, lead powder could completely pass the sieve sizing 106 um. About 50% of the precipitated lead dust of the plate-manipulating operation was smaller than 250 um. Particulates larger than 250 um dominate the precipitating lead dust of plate cutting operation, about 73% in weight. For size distribution, the diameter mode of lead powder material was about 11 ~ 13 um, while the diameter modes of precipitated dust, smaller than 250 um, of cathode plate-manipulating, anode plate-manipulating, and plate-cutting operations were 73 um, 169 um and 128 um, respectively. For lead component analysis, the dominant lead species of anode and cathode lead powder and precipitating lead dust of anode plate manipulation were Pb and PbO2. Main component of precipitated lead dust of cathode plate- manipulating and plate-cutting operations was Pb. Lead percentages in weight of lead powder, precipitated lead dust of plate-manipulating and plate-cutting operations were all higher than 80%. Results of in vivo animal study in part II shows that the relative bioavailability of precipitated lead dust of cathode plate, smaller than 106 um, were 69.3%, 37.2% and 49.5% at the 15th, 29th and 43th days, respectively, with the dose of 5.92 mg Pb/kg BW/Day. On the other hand, the relative bioavailability of precipitated lead dusts of cathode plate, smaller than 106 um, were 52.3%, 71.6% and 92.2% at the 15th, 29th and 43th days, respectively, with the dose of 9.37 mg Pb/kg BW/Day. Compared to other lead species, like lead-contaminated soil or lead ore concentrate, lead dust of battery plant was higher in lead weight percentage and had greater bioavailability. Results of this study provide significant information on lead dust bioavailability for further exposure and risk assessment in lead battery industry.