Agriculture and Environment: Cotton
Environmental Impacts of Production: Use of Agrochemicals
Globally, cotton accounts for 11% of all pesticides used each year, even though the area of production is only 2.4% of the world's arable land.
High consumption of agrochemicals
With regard to the subset of insecticides, cotton producers use 25% of all insecticides used each year. In developing countries, estimates suggest that half of the total pesticides used on all crops are applied to cotton.
Forty-six insecticides and acaricides (compounds used to control mites and ticks) comprise 90% of the total volume of all pesticides used on cotton. Five of these are classified as extremely hazardous, 8 as highly hazardous, and 20 are moderately hazardous (Soth 1999).
Risks of using highly toxic pesticides
The use of pesticides poses health risks to workers; to organisms in the soil; to migratory species such as insects, birds, and mammals; and to downstream freshwater species. Research on the cause of fish deaths in the United States showed that pesticides, even used with the proper application, harm freshwater ecosystems.
Serious water contamination from runoff
Endosulphan is a pesticide that is classified as highly toxic. In August 1995 endosulphan contaminated runoff from cotton fields in Alabama resulted in the death of more than 240,000 fish along a 25-kilometre stretch of river (PANUPS 1996). In another instance, gulls in Texas were killed 3 miles from cotton fields where parathion was sprayed when they ate insects that had been poisoned.
Effects on humans
Studies have estimated the human impact from pesticides used on cotton to be as high as 20,000 people killed and 3 million poisoned every year (IISD/WWF 1997). In addition to direct contamination in fields, people are also affected through water runoff, drift of sprayed mist, the use of empty pesticide containers for other purposes, and inadequate or illegal disposal of expired or unused pesticides (Banuri 1999).
The shift to chemical control of pests is relatively new, beginning after World War II. In the United States, for example, in 1950 cotton pests were controlled by agricultural management and tillage practices. Pest cycles were taken into consideration before planting and at harvesting. Crop rotations were used, sometimes unprofitably, to avoid insect infestations. Planting in lower densities also allowed producers to reduce the impact of pests.
Pesticides - perceived as cheaper alternative to other inputs
From the 1950s on, pesticides were seen as a cheaper alternative to the use of labour and machinery. Use peaked in the 1970s. By the late 1990s in California, an average of 9.1 kilograms (20 pounds) of pesticides (active ingredients only) were used each year per hectare of cotton production.
Aldicarb - frequently used, acutely toxic
This rate of usage has not changed in the past decade. The most acutely toxic pesticide registered by the U.S. Environmental Protection Agency is aldicarb (sold under the trade name Temik), which is frequently used on cotton. In fact, 85-95% of all aldicarb used in the United States is used on cotton. Aldicarb has been detected in the groundwater in 16 states (Monsanto 1999).
Pesticides make up by far the largest share of the agrochemicals used on cotton (67%). Herbicides make up about a quarter of all agrochemicals used, and fungicides a relatively small amount (5%). In many parts of the world the use of chemicals in cotton production is an even more recent phenomenon, but one rapidly increasing in scope.