Following an accidental explosion in an ammonia production plant some 10 tons of a mixture containing arsenic trioxide were released into the air, resulting in a wide contamination of the plant area and in a partial contamination of the nearby town of Manfredonia. Among other health and safety actions taken, all the factory employees (N = 917) and the temporary workers hired for repair, maintenance and clean up operation (N = 777) were examined in order to evaluate their possible arsenic intake. For every subject operating in the plant the total arsenic concentration in 24 hr urine samples was measured repeatedly (at least weekly). The measurements made in the three and a half months after the accident are considered in this paper. Urine arsenic concentrations were examined in their relationship to the following factors: age, smoking habit, residence, permanent or temporary employment, number of days worked in the contaminated area prior to the test. For the analysis multivariable methods were applied using prevalently SAS procedures. An extremely wide variability in the measurements was observed. This variability was not satisfactorily explained by the variables included in the adopted models. Only the place of residence provided a fair, but still partial, explanation for the observed variability. This may be due to two facts: the contamination of the town outside the factory; and the dietary habits, assuming a sea food consumption in coastal communities more frequent than in inland communities. No valid information on the individual dietary habits could, however, be collected. The failure of detecting any relationship between total urine arsenic concentration and number of days worked in the contaminated area prior to the test is most plausibly explained by the low validity of the test as biological indicator of intake. Recent studies on arsenic metabolism have, in fact, pointed out that measurement of total arsenic in the urine does not allow any distinction to be made between the amount of arsenic eliminated after occupational exposure and the amount deriving from other sources. These results stress the need for the measurement of various urinary fractions of arsenic (dimethylate, monomethylate and organic) in order to assess occupational exposure. It will also be necessary to revise the current biological limits for arsenic exposure.
|Translated title of the contribution||Evaluation of total urine arsenic concentration as biological indicator of occuational exposure|
|Number of pages||12|
|Journal||Medicina del Lavoro|
|Issue number||3 Suppl.|
|Publication status||Published - 1982|
ASJC Scopus subject areas
- Public Health, Environmental and Occupational Health