Exposure to Toluene Di-isocyanate and Respiratory Effects in Flexible Polyurethane Foam Industries in Western India

BACKGROUND: Flexible foam industry largely uses 2,4 and 2,6 Toluene di-isocyanate as main raw materials and chronic exposure to its result in occupational asthma. The exposure to di-isocyanates might be higher due to the usage of obsolete technology, hand-mixing methods and working in confined spaces with insufficient local exhaust ventilation systems in developing countries. Exposure studies in flexible foam industries have not been done in developing countries. OBJECTIVE: The present cross-sectional study was conducted to evaluate toluene di-isocyanate (TDI) exposures and respiratory health of the workers working in the seven flexible polyurethane foam industries located in Western India during 2010-2013. METHOD: A total of 128 personal air samples collected and evaluated for total TDI concentration using improved Occupational Safety and Head Administration method number 42. Then 194 workers were covered for complete clinical examination and spirometry for assessing respiratory health. RESULTS: In all, 17.83% of air samples exceeded the ACGIH TWA-TLV of 0.005 ppm for TDI. Though only 11 (5.6%) workers had respiratory complaints, the spirometry revealed that 19 (9.8%) and four (2.1%) had restrictive and obstructive type of pulmonary function impairment, respectively. CONCLUSION: The TWA concentration of TDI exceeded at raw material storage, mixing, foaming, block cutting and curing areas in four out of seven industries even in the presence of local exhaust systems. The respiratory health effect is less when compared to exposure to TDI, suitable preventive and control measures were suggested based on the study findings to the stakeholders to prevent the increase of respiratory health effects.