Statistical study of the correlation between mercury exposure (TWA) and urinary mercury concentrations in chloralkali workers.

The present report completes a previous study made on three chloralkali plants that was presented at the 8th International Conference on Occupational Health in the Chemical Industry, Tokyo, 1980, with the final results from five plants located in various regions of Italy. A total of 14,339 measurements of mercury in air and 8,042 determinations of mercury in urine were considered. The total number of workers involved was 275. On the basis of these data, we believe it can be concluded that, as previously reported, a correlation exists between mercury concentrations in the air and in the urine of exposed workers. This correlation is such that for exposures in the order of the present TLV (0.05 mg/m3), the value of the Z ratio (ratio between mean urinary mercury values expressed in mg/1 and mean airborne mercury concentrations expressed in mg/m3) is 1.3, while the urinary mercury values vary from 0.051 mg/1 to 0.078 mg/1 with a mean value of 0.065 mg/1.