The study of byssinosis in Guangzhou

Abstract

320 workers of two factories processingpure cotton were studied. 1306 subjects with-out occupational dust exposure were servedas controls. The median of inhalaboe dust,total dust and endotoxin were found to be 0.71(0.41-1.51),5.28(3.04-12.32)mg/m3 and 2007(1236-4100)EU/m3 respectively. The pre-valences of respiratory abnormalities in the cotton workers were(1)typical monday sym-ptoms: 9.0%,(2)pst-shift FEV1 falling by5.0%or more:16.8%,(3)post-shift FEV1falling by 10%or more 4.2%,(4)FEV1 lessthan 80% predicted:6.1%,(5)FEV1/FVCless than 75%:4.0%,(6)cough and/or phl-egm:18.2%,(7)chronic bronchitis:10.9% and (8)byssinosis defined by (1)plus(2) :1.7%.Comared with controls, the relative resks for the abovemedtioned abnormatities except(8)were:(1)30.0,(2)1.4,(3)1.7,(4)1.7,(5)1.2,(6)2.2 and(7)2.1 respectively. With the exceptionof (4),most of the prevalence increased withthe increase of age, duration of exposure and cumulative inhalable dust exposure. Inaddition, the levels of IgA, IgA and IgM ap-peared to be higher, and ANAE to be lowerin exposed group than those in the controls.