Monitoring of low level arsenic exposure during maintenance of ion implanters

To delineate potential exposure in ion implanter maintenance, the authors r ecruited 21 maintenance engineers (exposed group) and 10 computer programme rs (controls) at three semiconductor manufacturing facilities. Samples of a ir, wipes, and urine; used cleaning cloths; and used gloves were collected for the characterization of arsenic exposure. Arsenic levels were very low in environmental samples, but high arsenic levels were found in some wipe s amples, used cleaning cloths, and gloves. The average baseline content of u rinary arsenic measured for maintenance engineers was 3.6 mug/g creatinine. Maintenance engineers experienced an increase of 1.0-7.8 mug/g creatinine in urinary arsenic levels during ion implanter maintenance. Results of a mi xed-model analysis indicated that urinary arsenic levels were associated si gnificantly with time series (p = .0001), and the extent of association was different among the three facilities (p = .0226). The results of this stud y indicate that arsenic intake via ingestion, rather than through inhalatio n, might play a significant role in the elevation of urinary arsenic levels . However, a series of urine samples with self-reference continue to be a g ood approach for the monitoring of low-level arsenic exposure.