Cover Image
close this bookEnvironmentally Sound Technologies for Women in Agriculture (IIRR, 1996, 213 p.)
close this folderPests and pesticides
View the documentIntegrated pest management
View the documentNeem for plant protection
View the documentNeem oil as mosquito repellent
View the documentBiological control of malaria
View the documentNon-chemical methods of weed control
View the documentSafe use of pesticides
View the documentHazard of pesticides
View the documentPesticide facts and fiction
View the documentFirst-aid measures for pesticide poisoning
View the documentSave your crop from bird damage
View the documentBeekeeping

Hazard of pesticides


Human beings can be exposed to pesticides in two ways:

- Environmental exposure Indirectly through pesticide contaminated food, air, and water.
- Occupational exposure directly during the mixing, loading, or application of pesticides.

Symptoms of exposure

There are two main groups of pesticides, organochlorines and organophosphates. Look for these symptoms of exposure.

Organochlorines-skin irritation, burning sensation, stiff and sore muscles, headache, nausea and vomiting, abdominal pain.

Organophosphate-(mild exposure) headache, fatigue, dizziness, blurred vision, excessive sweating, nausea and vomiting, diarrhoea;(moderate exposure) inability to walk, chest discomfort, muscle twitching; (severe exposure) unconsciousness, convulsions.

While some people might understand the hazards of pesticides to human beings and animals, few know that indiscriminate use of pesticides can lead to deterioration of the environment and ecological imbalance. By far, most insect species are beneficial to humans. Each has an important place in the ecological system. But, pesticides kill beneficial insects and pests alike, disturbing the natural balance and leading to surges in pest populations. In time, the continuous use of pesticides leads to resistant pest populations. Combating these resistant populations with higher doses of pesticides leads to poisoned soil and water.

Effects on people

Disturbed cell metabolism

Human bodies are made up of tiny living cells. Pesticides make these cells sick, unable to fight off disease..

Congenital deformities

Pesticides accumulate in people, particularly in their fatty tissue and reproductive cells. This can lead to birth defects, abnormalities, abortions, and premature deliveries.

Impaired eyesight

Farm workers who regularly spray pesticides can suffer from impaired eyesight.

Liver damage

The liver is particularly susceptible to damage by one group of pesticides, the chlorinated hydrocarbons, which can lead to higher risk of serious infection.

Environmental exposure

Poisons are released into the environment when crops are treated with pesticides.

Air pollution

Air pollution results from spraying and dusting of pesticides in the field. Factories manufacturing pesticides also contaminate the air with their emissions.

Hazards of pesticides

Soil and water pollution

Rain soon after the application of a pesticide can wash poisonous pesticides into the soil and into surface and groundwater. Factories that manufacture pesticides might discharge pesticide-laced effluents that flow into surface water

Pesticides applied to crops can wash off into sources of water used for drinking and cooking.

Food contamination

Pesticide residue on fruits, vegetables, and grains is another threat to human health.

Animal products meat, milk, and eggs-can also contain pesticides. (Animals are often treated with pesticides to remove lice. They can also feed on fodder and grains treated with pesticides.)

Human bodies store pesticides, especially in fatty tissue. As a result, breast milk can be contaminated, affecting the health of infants. In fact, babies can be exposed to pesticides before birth.

Pesticides can contaminate all types of food.

Occupational exposure

Farm workers handle concentrated forms of pesticides. For them, the most common routes of pesticide exposure are:

Skin contact

Pesticides enter the body when liquid pesticides splash or spill on clothes or directly on the skin. Skin also absorbs pesticides in dust form. Cuts, abrasigns, sores, and wetness on the skin allow pesticides to enter more easily.

Do not let pesticides touch your skin.


Dusts, sprays, and fumes can enter the body through the lungs. Poor ventilation in pesticide stores results in increased exposure. (See Safe use of pesticides.)

Avoid Inhaling.

Oral contact

Pesticides are absorbed through the lips, mouth, and skin.

Pesticides are taken in by people who eat, drink, and smoke while handling pesticides, or who try to blow out clogged nozzles and hoses.

Do not eat while you are handling pesticides.

Eye contact

Pesticides can be absorbed into the body or eyes can be damaged, if pesticides blow or splash into the eyes.

Effects on insects

Besides killing insect pests, insecticides also kill beneficial insects, such as honey bees and other pollinators, parasites, and predators, thus disturbing the balance in nature. Uncontrolled, prolonged use of an insecticide can result in the breeding of insecticide-resistant pests, causing a resurgence or more virulent attack by insects.

Effects on plants

Excessive doses of pesticides can harm crops. Improper use of herbicides can harm the main crop, the following crop, and other useful vegetation grown later.

Effect on animals Pesticide residues can harm or even kill domestic animals as well as fish, birds, and other wildlife.

Contributors and sources: Dr. A. K. Kaheja, Dr. G. C. Tiwari, Ms. Sarojini Rengam and Karen Snyder