Mould infection, immunological tests and ventilatory lung function among cotton dust exposed workers

ABSTRACT

A cross-sectional study was carried out in the Shartex spinning and weaving company at Sharkia Governorate to determine the respiratory effect of cotton exposure. Seventy three cotton-exposed workers and 50 healthy workers [control group] were studied. Respiratory symptoms, ventilatory function tests, mycological examination of sputum and immunological examination for fungal reaction against different moulds and cotton extracts were assessed. Respiratory symptoms were frequently reported by exposed workers compared with controls. Among exposed workers, 11 [15.1%] had symptoms of byssinosis and 26 [35.6%] chronic bronchitis. This work has documented reduced lung function associated with work place exposure to cotton dust. Those workers with respiratory symptoms had significantly impaired lung function compared with asymptomatic workers Mould were significantly isolated from exposed workers than control group [P<0.001]. Different mould were isolated as Asp. niger, Cladosporium, Alternaria and others but only Asp. niger was the most significant isolate [P<0.01]. Also, exposed workers were more liable to develop immediate skin hypersensitivity reaction to specific cotton extracts [15.1%] and fungal antibodies [10.9%]. However, none of the control subjects gave either skin positive test to cotton extract or positive precipitin reaction. On regression analysis: both smoking and current exposure to cotton dust were the most significant risk factors of byssinosis, chronic bronchitis and impairment of both FEV1 and FVC.Also, duration of cotton exposure and increasing age were significant indicators for loss of FEV1 and FVC respectively.While, current cotton exposure was the only risk factor associated with frequent isolation of mould.In conclusion, workers exposed to cotton dust had increased respiratory symptoms and significant reduction in ventilatory capacity, also they develop immediate skin hypersensitivity reaction to cotton extract, fungal antibodies with more positive sputum culture for fungi than non exposed controls.So, it is recommended that lung function tests should be performed and can be used for routine medical surveillance. Also, anti-smoking programme must be applied