There was no significant correlation between air xylene concentrations with all parameters of lung functions and the respiratory symptoms. The air xylene in the individual breathing zone sampled, were very low and therefore, the association between these parameters were not seen. There were limitations in sampling the individual air since the sampling duration was short and the samples stored for about 2 - 3 weeks before analysis of xylene tend to vaporize. These low results may also be due to the effectiveness of the workplace ventilation. The employer seems to be concerned about the safety and health of the workers. However, there was a significant direct correlation between the air xylene and the urinary MHA. This result was supported by Kawai et al. (1991) study in which 121 male workers engaged in dip-coating of metal parts who were predominantly exposed to 3 xylene isomers that were o-, p- and m-xylene. Findings showed that there was a linear relationship between the exposure concentrations to xylene with the urinary metabolite MHA.