Pesticides are used in an attempt to beat the ever-increasing number of diseases affecting the banana plant. Banana production destined for export depends on chemical control. In Costa Rica alone, at least 280 different pesticides are authorised for use in the cultivation of bananas. The cost of pesticides is huge - in some cases as much as 30-40% of total costs. According to the International Union for the Conservation of Nature in 1995, the average use of pesticide in the banana plantations of Costa Rica is 44/kg/ha/year - compared to an average 2.7 kg/ha/year for crops in industrialised countries.
The EARTH College in Costa Rica (Escuela de Agricultura de la Region Tropical Humeda) estimates that of the fungicides applied by aeroplanes some forty times during each cultivation cycle (9-10 months), 15% is lost to wind drift and falls outside the plantation, 40% ends up on the soil rather than on the plants and approximately 35% is washed off by rain. This results in a 90% loss of the estimated 11 million litres of fungicide, water and oil emulsion applied each year to the banana production regions.
Companies believe that consumers want cosmetically beautiful bananas - one that looks perfect without marks or bruises. This ties companies to high levels of chemical use. But, ironically, after many years of massive applications of pesticides, the incidence of pests in banana plantations has not been noticeably reduced. On the contrary, scientists argue that there are more pests today than 50 years ago as pests and diseases are becoming increasingly resistant.