Uptake and Excretion of MSMA (Monosodium Salt, Methanearsonate Acid) in Workers Applying the Herbicide to Highway Rights of Way

摘要

The study followed uptake and excretion of total arsenic from MSMA in workers applying the herbicide during the spraying season. Urine, blood and hair samples were collected from workers as well as air samples taken from the workers breathing zone. Arsenic concentrations in air samples ranged from 0.001 - 1.086 micrograms per cu. m. with no significant difference in air arsenic concentrations over time. Blood arsenic values ranged from 0.0 - 0.2 mg/l, well within the limits considered normal. Arsenic urine values ranged from 0.002 - 1.725 mg/l. This is above the normal value range but is consistent with arsenic levels in urine following a seafood meal. Geometric mean arsenic concentration in urine increased during the week but returned to low levels on weekends. There was no accumulation of arsenic in urine over time. Hair arsenic concentrations ranged from 0.02 - 358.0 mg/kg. Arsenic concentrations increased during the spraying season but returned to preseason levels once herbicide application ceased. Three workers had pre-exposure values above the range considered normal for arsenic content of hair. However, only one of the three workers was consistently above normal values throughout the study period.