ABSTRACT
MDI [Methylene Diphenyl Diisocyanate] is a high tonnage product, which comprises about 90% of the total diisocyanate in the market. Polyurethanes are produced by reacting diisocyanate with polyols and other chemicals. They are known as respiratory tract and skin sensitizers and are the most common cause of occupational asthma in the world [NIOSH 1994]. On this subject, evaluation of MDI concentration in the polyurethane factories by HPLC, and is worthy to determine its pollution level. All sampling methods have some limitation, therefore, this survey the method of NIOSH 5522 has been used as a standard sampling and analyzing method t then, we utilize SPSS V.13 software, for our data to be analyzed for statistical discussion. Results showed that all of the polyurethane industries under this study have high concentration, rate of more than 80 micro g/m[3]. There was a strong correlation between indoor temperature and high MDI concentration, thus, it implies that various temperatures may be increased, in addition to working time ensuring it has a good correlation with MDI concentration. It also implies that when ever they have more working time comparatively, in turn, they have high exposure rate of MDI pollutant in the workplace. To obtain a better way for determination of MDI concentration in the workplace is using biological monitoring as a standard method to survey the exposure to diisocyanate, by using metabolite determination, it will be easier to collect and analyze more samples as the sampling is not as time-consuming as air monitoring