In addition to these metals and inorganic chemicals, people have used organic compounds, biological controls and cultural practices for a long time.

Alcohol from fermentation and acids in pickling solutions prevent growth of organisms that would otherwise ruin food. Spices were valued both for their flavors and because they deterred spoilage and pest infestations. Romans burned fields and rotate crops to reduce crop diseases. The Chinese developed plant- Derived insecticides and introduced predatory ants in orchards to control caterpillars 1,200 years ago. Many farmers still use ducks and geese to catch insects and control weeds.

Human Health Problems

Pesticide effects on human health can be divided into two categories: (1) shon- term effects, including acute poisoning and illnesses caused by relatively hig: doses and accidental exposures, and (2) long-term effects suspected to induce cancer, birth defects, immunological problems, Parkinson’s disease, and ot’re: chronic degenerative diseases. The long-term health effects may be caused b> very low doses of a variety of different chemicals and are difficult to tie to J specific source. The World Health Organization (WHO) estimates that some

million people suffer acute pesticide poisoning and at least 20.000 die each year. At least two-thirds of this illness and death results from occupational exposures in developing countries where people use pesticides without proper warnings or protective clothing.

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Alternatives to Current Pesticide Uses

Can we avoid using toxic pesticides or lessen their environmental and human- health impacts? In many cases, improved management programs can cut pesticide use between 50 and 90 percent without reducing crop production or creating new diseases. Some of these techniques are relatively simple and save money while maintaining disease control and yielding crops with just as high quality and quantity as we get with current methods. In this section, we will examine behavioral changes, biological controls, and integrated pest-management systems that could substitute for current pest-control methods.

Behavioral Changes

Crop rotation (growing a different crop in a field each year in a four-to six-year cycle) keeps pest populations from building up. Mechanical cultivation can substitute for herbicides. Flooding fields before planting or burning crop residues and replanting with a cover crop can suppress both weeds and insect pests. Habitat diversification, such as restoring windbreaks, hedgerows, and ground cover on watercourses, not only prevents soil erosion but also provides perch areas and nesting space for

birds and other predators that eat insect pests. Growing crops in areas where pests are absent makes good sense.

Humans have probably always known of ways to protect themselves from annoying creatures, but our war against pests entered a new phase with the invention of synthetic organic chemicals such as DDT. These chemicals have brought several important benefits, including increased crop production and control of disease-causing organisms.

A number of good alternatives offer ways to reduce our dependence on dangerous chemical pesticides. Among these are behavioral changes such as crop rotation, cover crops, mechanical cultivation, and planting mixed polycultures rather than vast monoculture fields. Consumers may have to learn to accept less than perfect fruits and vegetables. Biological controls such as insect predators, pathogens, or natural poisons specific for a particular

pest can help reduce chemical use. Genetic breeding and biotechnology can produce pest-resistant crop and livestock strains, as well. Integrated pest management (IPM) combines all of these alternative methods together with judicious use of synthetic pesticides under precisely controlled conditions.

Many of the procedures and approaches suggested for agriculture and industry also work at home to protect us from pests and toxic chemical alike. By using a little common sense, we can have a healthier diet, lifestyle, and environmental.