Effects of Pesticides on Non-target Species: When Pesticides Affect More than Just Pests

Pesticides are used to improve crop yields and promote human health by deterring and killing things such as harmful insects, ticks, mosquitoes, rats, mice, weeds, mold, mildew, bacteria, and other nuisance plants and animals. At times pesticides are extremely beneficial and even necessary to prevent disease and improve quality of life for humans. What many do not consider when using pesticides is the unintentional effect they have on beneficial organisms all around us.

Crops and Soil

Many pesticides sprayed on crops to prevent pest infestation and improve yield are actually extremely detrimental to the overall health of the soil, killing of beneficial soil microorganisms. This creates a need for more chemicals to restore health and balance to depleted soil, thus feeding a vicious cycle to our dependence on pesticides in farming and food production. This is simply not a sustainable method of food production.

Aquatic Life and Water Supply

All of the pesticides applied on land seep into the soil, affecting ground water, or run off and end up in our water ways and oceans. This has the potential to have a huge and devastating effect on aquatic plants and aquatic animals. All life on earth is dependent upon water, so if our water supplies become increasingly polluted, this could have a life-altering effect on every single species of life on earth.


With the heavy use of pesticides, both commercially and by the average homeowner, we are all exposed (intentionally and unintentionally) to them every single day. Over 95% of pesticides and herbicides used reach areas and organisms other than their targeted ones. Because of wind, run off, and poor disposal techniques pesticide exposure among the un-targeted population is very high. All of this exposure leads to resistance, and thus the need to develop more potent and more toxic substances to achieve the same results.

Human Toll

Pesticides are not good news for humans. They are the only toxic substances released legally and intentionally into our environment. If they are designed to incapacitate or kill smaller organisms, they are not healthy for humans. They have been linked to various short term effects such as nausea, headache, and fatigue, as well as long term problems including nervous system disorders, cancer, endocrine disruption, and fertility issues. The scary truth is we have very little idea of the effects of life long exposure to pesticides.

Because of environmental contamination pesticides are found all around us in the air, water, and soil, as well as in our food, cosmetics, and bodies. The truth is, some of the dangers are known, but to have toxins continually present in such high amounts is an unprecedented situation. The long term lasting effects on the human population and beneficial organisms are unknown.