DETERMINATION OF ATRAZINE LEVELS IN WHOLE SALIVA AND PLASMA IN RATS -POTENTIAL OF SALIVARY MONITORING FOR OCCUPATIONAL EXPOSURE

Current biological monitoring techniques are often unable to provide a ccurate estimates of pesticide dose in exposed worker populations. Thi s study was conducted to investigate the feasibility of pesticide biom onitoring using saliva. Atrazine hloro-4-ethylamino-6-(isopropylamino) -s-triazine], a member of the triazine herbicides, was selected to inv estigate salivary excretion following direct gastric administration in rats. Concentrations of atrazine in whole saliva and arterial plasma samples were determined by enzyme-linked immunosorbent assay (ELISA). Atrazine reached its highest level in both arterial plasma (238 mu g/L ) and whole saliva (157 mu g/L) 35 min after administration of 105 mg/ kg of atrazine, and then decreased with time in a parallel fashion. Al though saliva atrazine levels were lower than levels in arterial plasm a, there was a very high correlation between whole saliva and arterial plasma atrazine concentrations (r(2) =.95). In addition, pharmacokine tic analysis suggested that salivary levels of atrazine can be used to predict concentrations of atrazine in plasma. The mean whole saliva/a rterial plasma atrazine concentration ratio (S/P) was 0.66 +/- 0.11 (n = 20). The S/P ratios did not vary significantly over time, and were not affected by salivary flow rate. This study demonstrates that atraz ine is transported into saliva, and that a relatively constant concent ration ratio between whole saliva and arterial plasma is maintained. B ecause the salivary concentrations of atrazine are independent of vari ation in salivary flow rate, salivary monitoring of atrazine in humans may prove useful and practical. Finally, this study suggests that oth er pesticides with chemical and physical properties similar to those o f atrazine can be monitored in saliva.