Environmental impact of pesticides
[3] Alternatives to heavy use of pesticides, such as integrated pest management, and sustainable agriculture techniques such as polyculture mitigate these consequences, without the harmful toxic chemical application.
From their cost effectiveness to their assistance in decreasing disease spread, and increasing crop production, these pesticides appear to be a great resource.
Crop yields increased significantly through the discovery of 2,4-D.[11][12][13][14] Many insect infestations were addressed by DDT, greatly lowering rates of typhus and malaria worldwide.
Shortly thereafter, DDT, originally used to combat malaria, and its metabolites were shown to cause population-level effects in raptorial birds.
Bayer CropScience and its acquisition of Monsanto led it to record profits in 2019 of over $10 billion in sales, which herbicide shares growing by 22%, followed closely by Syngenta.
Some pesticides, including aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, mirex, and toxaphene, are considered POPs.
[42] POPs can affect non-target organisms in the environment and increase risk to humans[43] by disruption in the endocrine, reproductive, and respiratory systems.
[44] and certain authors maintain that pesticide risk and impact assessment models rely on and are sensitive to information describing dissipation from plants.
[50] Pesticides that are applied to crops can volatilize and may be blown by winds into nearby areas, potentially posing a threat to wildlife.
[51] Weather conditions at the time of application as well as temperature and relative humidity change the spread of the pesticide in the air.
[54] Farmers can employ a buffer zone around their crop, consisting of empty land or non-crop plants such as Evergreen trees to serve as windbreaks and absorb the pesticides, preventing drift into other areas.
[65][66] The United Kingdom sets Environmental Quality Standards (EQS), or maximum allowable concentrations of some pesticides in bodies of water above which toxicity may occur.
Depending on the chemical nature of the pesticide, such processes control directly the transportation from soil to water, and in turn to air and our food.
Aging mechanisms are poorly understood but as residence times in soil increase, pesticide residues become more resistant to degradation and extraction as they lose biological activity.
[75] Root nodule formation in these plants saves the world economy $10 billion in synthetic nitrogen fertilizer every year.
The USDA and USFWS estimate that US farmers lose at least $200 million a year from reduced crop pollination because pesticides applied to fields eliminate about a fifth of honeybee colonies in the US and harm an additional 15%.
Residues can travel up the food chain; for example, birds can be harmed when they eat insects and worms that have consumed pesticides.
[84] Some pesticides can bioaccumulate, or build up to toxic levels in the bodies of organisms that consume them over time, a phenomenon that impacts species high on the food chain especially hard.
[90] In the past several decades, amphibian populations have declined across the world, for unexplained reasons which are thought to be varied but of which pesticides may be a part.
Tadpoles from ponds containing multiple pesticides take longer to metamorphose and are smaller when they do, decreasing their ability to catch prey and avoid predators.
Across the United States and Canada disorders such as decreased hatching success, feminization, skin lesions, and other developmental abnormalities have been reported.
[98] Epidemiological studies have reported adverse effects of certain pesticides at current levels of exposure on children's cognitive development.
Exposure effects can range from mild skin irritation to birth defects, tumors, genetic changes, blood and nerve disorders, endocrine disruption, coma or death.
For example, the northern corn rootworm (Diabrotica barberi) became adapted to a corn-soybean crop rotation by spending the year when the field is planted with soybeans in a diapause.
[113] Prior or during the development of synthetic pesticides, many natural ones were identified including pyrethrum, rotenone, nicotine, sabadilla, and quassin.
[116] Biopesticides such as canola oil and baking soda that contain curtain active ingredients from natural substances are an environmentally friendly alternative for toxic pesticides.
Research has been done on different methods to treat pesticide pollution including the use of activated carbon absorption and advanced oxidation processes.
[126] While dubbed economic and ecologically sound practices by suppliers, the effects of agricultural pesticides can include toxicity, bioaccumulation, persistence, and physiological responses in humans and wildlife,[127] and several international NGOs, such as Pesticide Action Network, have risen in response to the economic activities of these larger transnational corporations.
Historically, PAN's contributions targeting the Dirty Dozen have resulted in treaties and global environmental law banning persistent organic pollutants (POPs), such as endosulfan, and their campaign work on Prior Informed Consent (PIC) for countries in the Global South to know what hazardous and banned chemicals they might be importing have contributed to the culmination of the Rotterdam Convention on Prior Informed Consent, which went into effect in 2004.
[128] PAN's work, according to their website, involves "shifting global aid away from pesticides",[129] in addition to community monitoring and serving as a watchdog for the World Bank policy failures.
