In 1992, Brazil modified its toxicological classification criteria for pesticides. This modification aimed to follow the guidelines of the World Health Organization (WHO) hazard classification of pesticides. In 2002, the United Nations adopted the "Globally Harmonized System for the Classification and Labelling of Chemicals" (GHS). As a result, the WHO is reviewing its classification and Brazil will probably follow the example. Therefore it seems timely to estimate the impact of the changes in the criteria adopted in 1992 in the toxicological reclassification and labelling of the commercially available products registered at that time. It is estimated that 58.6% of the total of registered pesticides (74.9% liquid and 31.0% solid formulations) might have been reclassified to less hazardous classes. The hazard warnings on the labels may have caused negative consequences due to misinterpretations by farmers or rural workers. For countries already having a hazard classification system, it is therefore recommendable to estimate the possible impact of the changes before implanting the GHS.
GHS; Pesticides; Risk communication; Toxicological classification; Hazard classification; Chemicals
