Histological changes, rhinoscopical findings and nickel concentration in plasma and urine in retired nickel workers.

Histological examination of nasal biopsy specimens, rhinoscopical evaluation and nickel analysis in plasma and urine were performed on 59 retired nickel workers. The histological characteristics were graded according to a numerical classification table. Workers with short employment and short retirement time had a significantly lower mean histological scores than those with long employment and long retirement. Thirteen persons (22%) showed epithelial dysplasia, possibly representing precancerous lesions. Also included in the material were four cases of nasal carcinoma. Presence of hyperplastic/polypoid nasal mucosa was inversely related to the duration of retirement, possibly reflecting gradual regression of the mucosal swelling after termination of the irritation. The nickel concentration in plasma and urine was significantly higher among former roasting/smelting workers than in former electrolysis and non-process workers. This is probably a consequence of the slow release of heavy soluble nickel compounds that have accumulated in the organism at the former place of work.