Biological monitoring in nickel refinery workers

A study was carried out at the Clydach, Wales, refinery of INCO Europe Ltd, in which urinary and serum nickel levels were compared with results derived from personal atmospheric sampling during: (a) normal operating conditions; (b) after a prolonged lay-off; and (c) one month after resumption of normal activities. On an individual basis, poor correlations between atmospheric and biological monitoring were observed but when work groups were considered it was found that atmospheric insoluble nickel correlated with both urinary nickel (correlation coefficient = 0.86, p = 0.02) and serum nickel (correlation coefficient = 0.87, p = 0.02). Men using respiratory protection had biological levels which were approximately one-quarter of what would have been expected from the atmospheric figures and men working with soluble nickel salts had urinary nickel levels three times in excess of those expected. There was no statistical difference between observed results and those corrected for creatinine content or specific gravity, nor was there any difference between randomly collected or first morning urine samples. Biological monitoring of nickel workers can be considered as having a role to play in assessing whether protective measures at the place of work are functioning properly, and a tentative scheme is suggested which could make use of biological monitoring, together with atmospheric monitoring, in the occupational health care of refinery workers.