Ann. occup. Hyg., Vol. 17, No. 1, pp. 57-63, 1974
© 1974 British Occupational Hygiene Society
Published by Oxford University Press
research-article |
CARBOXYHAEMOGLOBIN LEVELS IN BLAST FURNACE WORKERS
British Steel Corporation, Strip Mills Division, Gabalfa Cardiff
Carboxyhaemoglobin levels at the beginning and end of a single work shift were estimated in workers at an integrated steelworks using the expired air method. A hundred blast furnace workers and a randomly selected control group of eighty-seven men with no occupational exposure to carbon monoxide were tested over a five-day period. The method proved simple, accurate and very suitable for this type of investigation. A previous study in 1962 had shown that irrespective of smoking habits, blast furnace workers had significant increases in carboxyhaemoglobin levels in end-of-shift samples, whereas those in the control group had not. Those findings were confirmed and, from the similarity of the results in 1962 and 1973, it is deduced that blast furnace workers have been exposed to comparable small concentrations of carbon monoxide during the intervening period.
Thirty-two blast furnace workers and twenty men in the control group who were smokers had carboxyhaemoglobin levels of five per cent or more at the beginning of their shifts before having any working exposure to carbon monoxide. Difficulties arising from the United States National Institute for Occupational Safety and Health recommendation that occupational exposure to carbon monoxide should not exceed 35 ppm as a time-weighted average for an 8-hour workday are considered in the light of these findings.