Abstract

Khogali, M. (1969).Brit. J. industr. Med.,26, 308-313. A population study in cotton ginnery workers in the Sudan. An epidemiological study in cotton ginneries in the Sudan covered 323 permanently employed ginnery workers, a random sample of 35 seasonal farfara workers, and a control group of 24 members of a fire brigade. All the workers studied were men.

The study showed a prevalence of byssinosis (defined as chest tightness starting on return from the annual holiday and continuing for at least three consecutive days) in 20% of the ginnery workers and in 48·6% of the farfara workers. Workers exposed to dust showed a mean fall in F.E.V._1·0 of -0·10 litre during the shift, while workers not so exposed showed a mean rise of +0·23 litre; this difference was statistically significant. The F.E.V._1·0 was adjusted for age and standing height. The adjusted means of F.E.V._1·0 were significantly lower for workers exposed to dust compared with those in the control group.

The workers with byssinosis showed a statistically significant fall in F.E.V._1·0 when compared with all ginnery workers; and a highly significant fall when compared with cotton workers without chest symptoms. An attempt was made to grade the byssinotics according to the extent of fall in F.E.V._1·0 during the shift.

The concentration of fine dust (< 7 μ) was measured in each work place. There was a statistically significant association between the prevalence of byssinosis and the concentration of fine dust when comparing the ginnery and farfara workers. Also, there was a significant relationship between the mean adjusted F.E.V._1·0, the mean fall in F.E.V._1·0, and the fine dust concentration.