Glyphosate

Abstract

Evaluates the risks to human health and the environment posed by glyphosate, a post-emergent, systemic, and non-selective herbicide used, primarily against deep-rooted perennial species, in agriculture and forestry, and for weed-killing in water systems, parks, road verges, and gardens. Roundup is the major formulation of glyphosate. Because of its agricultural uses, concern centres on the possible presence of residues in crops and animal tissues destined for human consumption. Concerning possible presence of residues in crops and edible animal tissues, the report cites evidence that such residues are negligible. The report further concludes that the low toxicity, low volatility, and low body absorption of glyphosate make its application by backpack sprayer safe when workers wear full protective clothing. A review of studies in laboratory animals and in vitro test systems supports the conclusion that glyphosate has very low toxicity when administered by the oral and dermal routes, does not induce sensitization, and shows no mutagenic, carcinogenic, or teratogenic activity. While the formulation Roundup is acutely toxic to humans when ingested intentionally or accidentally, dermal absorption is low, and no adverse effects are expected in properly protected workers. Studies of adverse effects on other organisms in the laboratory and field demonstrate low toxicity for bees, earthworms, and birds. The risk to most aquatic organisms was judged to be small or negligible. While marked changes in populations of birds and small mammals have been documented following glyphosate application, these changes are attributed to alterations in habitat, vegetation cover, and food supply resulting from the herbiide s intended effects