Workplace assessment of naphtha exposure in a tire manufacturing industry.

A qualitative and quantitative workplace assessment was carried out to determine naphtha exposure in a tyre manufacturing industry. A qualitative chemical health risk assessment was conducted to identify naphtha hazard at the workplace. Quantitative assessment using Portable VOC Monitor, Automatic Sampling Pump and personal air sampling pump was used to determine VOC concentrations, organic solvents, and individual air naphtha respectively. The risk rating of naphtha was estimated to be 5. The mean VOC concentration was in the range of 2.43 to 92.93 ppm. Repair area had the highest VOC concentration while the lowest was in the moulding area. Each work station had significant differences for VOC concentrations (p < 0.001). Laboratory analysis found various solvents including 2-methyl pentane, hexane, methyl cyclopentane, heptane, cyclohexane and toluene which were present in the liquid naphtha. Only xylene has been detected in the making and moulding areas with a range of 2 to 5 ppm. Meanwhile, the air naphtha concentrations of the exposed workers were significantly higher than those unexposed. The risk of naphtha exposure was qualitatively significant and not adequately controlled. Naphtha was detected in all work stations since it is the main solvent used. The “Repair Area” was significantly more contaminated than the other area

Toxic effect of naphta exposure on respiratory system among workers in the tyre industry

A cross-sectional study was carried out on workers in a tyre manufacturing industry in Malaysia to determine the effects of naphtha exposure on lung functions and respiratory symptoms. Sixty male workers exposed to naphtha and 42 unexposed workers were selected for this study. Personal air monitoring carried out using solid sorbent tubes and low flow pumps (Model: PAS-500 Personal Air Sampler). Personal air monitoring showed that the mean air naphtha concentration was 28.50 mg/m3, the median was 28.47 mg/m3 and the inter quartile range of 1.27 mg/m3. The range was from 0.19 to 200.51 mg/m3 (PEL is 400 mg/m3). The lung function tests showed in 2 groups for all the 3 parameters (FVC%, FEV1% and FEV1/FVC) were in exposed group 96.16, 85.23 and 0.791 respectively and in Unexposed group was 113.23, 116.28 and 0.903 respectively. The lung function tests showed that there were significant difference in the 2 groups for FVC% (p < 0.001), FEV1% (p < 0.001) and FEV1/FVC% (p =0.002). Multiple linear regression test showed that monthly household income significantly influence the FVC% predicted (b = 0.003, p < 0.001) and FEV1% predicted (b = 0.006, p < 0.001). In conclusion there was an inverse relationship between air naphtha concentrations and lung functions ability. Early impairment of the respiratory system is detected on the workers who are exposed to naphtha which made up of several chemicals