Investigation of a Working Population Exposed to Thallium

摘要

Biological monitoring by urinary thallium estimation was found to be a useful method of screening a population exposed to thallium and was used for showing the effects of an education programme and improved industrial hygiene. An alerting level for urinary thallium is suggested.A cohort study involving a population of workers exposed to thallium and a control group was performed to determine whether there were any clinical effects attributed to this toxic metal. There was no statistically significant difference.No data exists from which to derive a control limit for thallium. A threshold limit of 0.1 mg/m3has been set for thallium by the American Conference of Governmental Industrial Hygienists, and is based largely on analogy with other highly toxic heavy metals. It is suggested that the safety of the present threshold limit is supported by this study.