Hazards of insecticide use in cotton cropping in Togo from 1990 to 2010

Abstract

For many people, cotton remains associated to a crop which consumes the most insecticides harmful to human health and environment. This negative appreciation of cotton production is no longer valid according to an international study of the Expert panel on Social, environmental and Economic Performance of cotton production (SEEP), but cotton-producing countries have seldom analyzed and informed about the evolution of insecticide use. This article fills this gap in the case of Togo. It deals with a study based on data reconstituted for cotton areas and insecticides distributed to producers in Togo, from 1990 to 2010. Data on insecticides pertained to amounts distributed and to their compositions of active ingredients, so that the amount of active ingredients per hectare could be computerized. Besides, referring to the above-mentioned international study which had compiled the ecotoxicity indexes of all active ingredients from various sources, toxicological loads against various fauna components have been calculated to assess the hazards of the insecticide used. These loads were defined to enable capturing the evolution over time and to compare countries. In Togo, the amount of active ingredients per hectare has steadily decreased till one liter, at a level similar to Australia which has in addition adopted genetically modified varieties. The toxicological load, on human beings as well as on various fauna components, like bees or daphnia in rivers, has diminished although less steadily. This evolution has resulted from a limited chemical pest protection of cotton crop with less than six sprays over three decades and from the adoption of new generations of insecticidal molecules. In Togo, the use of insecticides in cotton cropping has evolved in a more friendly way to human health and environment protection. This evolution should be valid as well in all cotton producing countries in French speaking Africa where similar studies are worth being carried out.