Synthetic and natural agricultural chemicals include herbicides to control weeds, insecticides to reduce damage from plant bugs, and fungicides to limit fungus-causing diseases. They are used by all farmers, organic and conventional. Pesticides enabled the “green revolution”, an extraordinary period of food crop productivity growth that has seen US crop yields more than triple. It has led to affordable food in markets and grocery stores around the world. Formerly impoverished countries like Bangladesh and India have rapidly become self-sufficient for staple foods and now even export products such as cotton.
There are some environmental benefits. The use of herbicides in the United States, Australia, Brazil, Argentina, and other countries has allowed the widespread adoption of low- and no-tillage systems that limit polluting carbon release, improved profitability in broad-acre agriculture, and reduced soil erosion and soil health.
Chemical use is controversial. Pesticides are toxic — they are designed to kill pests — and if not managed correctly can have off-target effects on soil, animals, and humans. Fortunately, regulators around the world set hazard limits with very wide cushions built in to protect humans and wildlife.
Nonetheless, controversies erupt over one chemical or another after reports by oversight agencies or environmental groups. Organic chemicals can be more or less harmful than synthetics, which are designed to be targeted. One of the most widely spread chemicals in the world, natural copper, is the most common fungicide used by wine-growing organic farmers. It can cause severe cellular, kidney, and liver damage in humans and animals, and can be toxic to plants as it inhibits photosynthesis.
This site provides background on pests and plants, and highlights the debate over the safe use of chemicals in farming. What level of exposure is threatening? How can the public and the press assess the scientific credibility of corporate and environmental group campaign claims? We’ve assembled a growing collection of articles and commentaries to help sort science from propaganda.