Exposure of xylene in working environment and methylhippuric acid in informal footwear worker in Bogor, Indonesia

Introduction: The use of adhesives and paints containing xylene play an important rule in footwear manufacturing. Xylene exposure can affect the central nervous system. To determine the level of exposure can be conducted by measuring the levels of methylhippuric acid (MHA) in urine. The aim of this study was to describe the risk of xylene exposure to workers’ health. Method: This study used cross-sectional design and conducted in three footwear workshops in Ciomas, Bogor Regency in September – October 2017. The study sample consisted of 40 urinary workers and 9-point measurements of xylene in indoor air. Especially, urine (MHA) was taken at the end of work hours and analyzed with UPLC MS/MS. Furthermore, xylene measurements were carried out using gas chromatography. For the analysis of the relationships between the concentration of xylene and MHA levels using simple linear regression. Results: The concentration of xylene in the workshops was 0.00358 mg/m³ (median) with the highest concentration at the sample point 6 (0.03161 mg/m³). MHA in the urine of all workers was 0.000100 g/g of creatinine (median). From the statistical results, there was no statistically significant relationship between xylene concentration and MHA (p = 0,511). Conclusions: There was a positive linear correlation between xylene concentration in indoor air of workplace increased and the level of MHA in urine. It means the higher the xylene concentration, the more MHA level.