Study of Variation in Breath Holding Time on Exposure to Mill Dust in Rice Mill Workers

Due to industrialization and global competitive market trend, rice mill has emerged as a major industrial activity in small medium scale sector to cater to the needs of increasing population. Indoor air pollution is a major problem in developing countries and is increasing more and more due to rapid industrialisation and ineffective pollution control measures. Occupational exposure to rice husk dust have been shown to affect functioning of different systems of the body.

1. To assess the Breath holding time (BHT) among rice mill workers compared to controls and 2. To know whether the rice mill dust has any effect on BHT with duration of working (in years) among the rice mill workers.

Fifty non smoking male adult workers from various rice mills were selected for the study and fifty age and BMI matched individuals who were not exposed to such occupational hazard were taken from the general population of Mysuru city as controls. Breath holding time was recorded using mercury manometer where the subjects were advised to blow through the mouth piece after full inspiration as long as possible till the breaking point following standard methods and precautions and were statistically analysed by using student's ‘t’ test. Further the cases were classified according to the duration of exposure and inter group comparisons were made using one way Anova.

Rice mill workers showed significant decline in Breath holding time compared to controls. Also, there is a significant deterioration in breath holding time as the duration of exposure prolongs.

The breath holding time was significantly declined among rice mill workers compared to controls. The findings are of importance that they demonstrate the extensive need of preventive measures to be implemented. It is advisible therefore to adopt technical preventive measures such as having a well-ventilated work areas and wearing appropriate respiratory protective devices in rice mills.