What Are Organochlorine Pesticides?

two men spraying pesticide on plants
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Most pesticides are bad news, but organochlorine pesticides are super long-lasting pesticides, which makes them very bad news. So bad that most organochlorine pesticides have been banned in North America and Europe. However, the chemicals are still in use in Central America, India, China and countries in Africa.

Also known as persistent organic pollutants (POPS), organochlorines have extremely strong bonds between their chlorine and carbon components and are attracted to fats. They are also highly insoluble in water, meaning they don’t dissolve, and when it rains, they can spread widely through runoff. The problem with this strength is that once organochlorine pesticides are used, they stay around for a long time, not only in the water supply and in the soil but also in human and animal bodies.

Bug Killers

The biggest application for organochlorine pesticides is as an insecticide, and they were widely used from the 1940s to the 1960s in the United States and Europe. Probably the most infamous organochlorine insecticide is DDT. It was so effective as a mosquito killer, enabling an estimated one billion people to live free from fear of malaria, that the chemist who discovered its insecticide powers received a Nobel Prize. DDT was used widely in the United States until biologist Rachel Carson published her groundbreaking book Silent Spring, which warned of the toxicity of the chemicals. Scientists confirmed DDT had disastrous effects on the reproductive abilities of birds, fish, and marine animals, and it was banned in the United States in 1972.

By the time it was banned, however, 1.2 billion pounds of the chemical had already been applied throughout the country. Thirty years later, testing still found evidence of the chemical in air, water, and rain, soil and dust, plants, animals and humans, including people born long after the DDT ban went into effect. Yet in 2006, the United Nations began promoting DDT's use in countries that allow it to control mosquitoes and combat malaria, which kills more than one million people each year. 

Getting in Your System

When used, organochlorine pesticides can leach into the environment via direct application, contaminated waste disposal, incinerator emissions or runoff. If you are near an area where an organochlorine pesticide has recently been applied, you can actually inhale the chemicals. You can also ingest them by eating contaminated foods, such as fish, dairy products and other foods with higher fat contents.

Since organochlorine pesticides don't break down easily in fatty tissue, they can build up in animals and humans and even be passed on in this manner. For example, studies show that when a human or bird or other fish eats a fish that is contaminated with an organochlorine pesticide, that pesticide is passed on to the eater.

Long-term exposure in humans can have serious health effects, including damage to the liver, kidney, thyroid gland, bladder, and central nervous system as well as serious reproductive problems.

Symptoms of Exposure

Long-term exposure can cause headaches, confusion, and dizziness; digestive problems such as abdominal pain, nausea, vomiting and diarrhea; agitation or a sense of apprehension; and weakness, loss of muscle control and tremors, even seizures. You also may suffer skin, ear, nose or throat irritation and breathing problems or a cough. If you suspect you suffer from exposure, see your doctor.