A comparative toxicologic and genotoxic study of the herbicide arsenal, its active ingredient imazapyr, and the surfactant nonylphenol ethoxylate

Genotoxicity and toxicity studies were performed to test effects of 250NA, technical grade imazapyr, and nonylphenol ethoxylate (NP, a surfactant) on multiple organisms. Toxicity tests were performed on mice, flies (Drosophila melanogaster), and the snail Biomphalaria tenagophila. Genotoxicity tests were performed on mice micronuclei, from extracting bone marrow from exposed mice, and also examining the mitotic index of exposed onions (Allium cepa).

As far as toxicity, nonylphenol (the surfactant) was most toxic to mice, D. melanogaster, and B. tenagophila, and imazapyr was the least toxic. None of the tested chemicals had significant effects on mice micronuclei or on chromosome aberrations in A. cepa. However, arsenal and nonylphenol did cause lagging chromosomes in A. cepa, suggesting mitotic spindle disturbance.