Introduction For nearly 300 years, work in textile industry has been recognised as hazardous. Continuous exposure to cotton dust is associated with progressive impairment of pulmonary function and with respiratory tract symptoms (byssinosis).

Methods Suspended fine dust was measured in a representative sample of factories with the Grimm Portable Aerosol Spectrometer 1108 (Grimm Aerosol Technik, Germany). From the size-dependent particle number particle mass in standardised size ranges (environmental standards: PM2.5 and PM10, occupational standards: inhalable, thoracic and alveolic) are calculated. In total 109 cotton workers (51 from power looms, 58 from large factories) and 52 workers not occupied in the cotton industry as controls were investigated by spirometry in a cross-sectional study. The 51 power loom workers and also 51 unexposed controls provided buccal smears to be analysed for cytotoxic and genotoxic damage.

Results Dust levels were especially high in small weaving factories (so-called power looms) where mainly unskilled workers (starting to work at an early age) are employed for long (12 hour) working shifts. Work duration in years was associated with declines in all spirometric indices studied (% of norm of FVC, FEV1, FEV1/FVC%, PEF, MMEF). Risk of obstructive lung disease increased by more than 5% per year of occupational exposure. Workers from power looms performed worse than workers in larger factories but the study lacked the power to disentangle the effects of duration and intensity of exposure. Signs of cytotoxicity in buccal cells were higher among exposed workers. With increasing duration of occupational exposure also genotoxic damage increased.

Conclusion Occupational health and safety are still burning issues in developing countries. Poor industrial hygiene and poor health could be documented in the cotton industry, which is an important sector of the Pakistani economy.