Occurrence of triazine herbicides and metolachlor in the Niagara River andother major tributaries draining into Lake Ontario

Immunoassay methods for triazines and metolachlor as a screening tool were evaluated at the National Laboratory for Environmental Testing (NLET), Corr elation coefficients (R-2) of 0.992 for triazines and 0.999 for metolachlor were determined. The detection limits were statistically calculated to be 0.070 ppb for triazines and 0.012 ppb for metolachlor. Immunoassay results for samples from the Niagara River were compared to the conventional GC/MS method. Immunoassay results were consistently biased high. Based on immunoa ssay results, concentrations in Lake Ontario tributaries ranged from 5 to 1 650 ng/l for triazines and 15 to 225 ng/l for metolachlor. (C) 1998 Elsevie r Science B.V. All rights reserved.