BIOMARKERS IN HYDROLYZED URINE, PLASMA AND ERYTHROCYTES AMONG WORKERSEXPOSED TO THERMAL-DEGRADATION PRODUCTS FROM TOLUENE DIISOCYANATE FOAM

Blood and urine samples were collected from six workers and two volunt eers exposed to thermal degradation products from toluene diisocyanate (TDI)-based polyurethane (PUR) before and during the summer vacation. Air samples were collected on filters impregnated with 9-(N-methylami nomethyl)anthracene. The concentrations of the amines corresponding to 2,4- and 2,6-TDI, i.e., 2,4- and 2,6-toluenediamine (TDA), mere deter mined in urine (U-TDA), plasma (P-TDA) and erythrocytes (E-TDA) after acid hydrolysis as pentafluoropropionic anhydride derivatives by GC-MS . Among the workers urinary elimination phases were seen, The estimate d medians of the urinary half-lives were for the slow phase 18 d for 2 ,4-TDA and 19 d for 2,6-TDA, P-2,4-TDA ranged between 2.5 and 19 ng ml (-1) and P-2,6-TDA between 4.4 and 30 ng ml(-1). The estimated median of the half-lives in plasma were 7.8 d for 2,4-TDA and 9.6 d for 2,6-T DA, E-2,4-TDA ranged between 0.5 and 6.6 ng g(-1) and E-2,6-TDA betwee n 1.2 and 14 ng g(-1). A significant linear relationship was found bet ween the mean P-TDA and the mean E-TDA, Linear relationships were obse rved between the mean daily U-TDA and P-TDA and ETDA, Virtually Linear relationships were obtained for P-TDA and E-TDA and the TDI air level s, Proteins from lysed erythrocytes were separated and fractionated by gel filtration, 'TDI'-modified proteins were found in six out of a to tal of 80 fractions (fractions 51-56), These co-eluted completely with the haemoglobin (UV, 415 nm), Fractions 51-56 contained 89% of the ap plied amounts of 2,4-TDA and 81% of 2,6-TDA.