Original article

Scand J Work Environ Health 1985;11(2):97-100    pdf


Urolithiasis in railroad shopmen in relation to oxalic acid exposure at work.

by Laerum E, Aarseth S

It is well known that the urinary excretion of oxalic acid is one of the main determinants for urinary stone formation. From 1950 to 1978 a saturated oxalic acid solution was used in a repainting and cleaning process for railroad cars in Norwegian railroad workshops. With the use of a questionnaire, the cumulative prevalence of urolithiasis-induced colic episodes was registered in the Sundland railroad depot. Forty-two (11.9%) out of 353 male workers not exposed to oxalic acid reported having had one or more such stone colic episodes. The corresponding figure for 15 individuals who had a very high exposure to oxalic acid was 8 (53.3%). Also workers in other departments, occasionally exposed to oxalic acid, had an increased stone colic prevalence rate, a finding suggesting a positive dose-response relationship. There was an increased frequency of stone colic episodes in the age group 40-69 years. Seven heavily exposed workers in the paint shop reported initial pollakiuria and slight dysuria during the exposure. The study indicates a causal relation between urinary stone formation in the investigated railroad shopmen and their exposure to oxalic acid at work.