Stonyfield Organic

Health Effects Of Pesticides

Pesticides are chemicals used for preventing, destroying, repelling or mitigating pests and include herbicides that are used to kill weeds and insecticides, which destroys insects, as you might have guessed. And in the U.S., we use a lot.

over one billion...

Herbicide Sprayed On Weed
Over one billion pounds of pesticides are used annually in the U.S., according to the most recent EPA data [page 20, table 3.2]. And 11% of that is destined for use outside of agricultural settings, including on parks, school grounds, and athletic fields. While the benefits of this pesticide use are immediate and obvious—green lawns, smooth playing fields—its’ hazards are not.

Too often left unnoticed are the costs that come with those chemically laden fields. The effects of toxic persistent pesticide exposure on human health have been well researched and documented, yet most people are not aware of the risks. It’s an ‘aha moment’ for many communities when they find out the risks children in particular are exposed to as they play on soccer fields or picnic in the local park.

Glyphosate and 2, 4-D are two of the most commonly used herbicides used on playing fields. They are sold under many different trade names and are often found packaged as a fertilizer/herbicide mix.  There is a good chance you have a few in your garage or basement.  With a host of other pesticides, including dicamba, pyrethoids and neocontinoids, these ‘Weed and Feed’ products are part of a toxic arsenal used to manage the green spaces where children, families, and the general public live, eat and play.

general health risks

Back in 2004, a National Cancer Institute-led report concluded that, “evidence clearly suggests that at current exposures pesticides adversely affect human health.” This was true not just for professionals who handle pesticides in their work, but also for the rest of us who encounter pesticides at low levels in our daily lives.


In 2015, the International Agency for Research on Cancer (IARC), a division of the World Health Organization, found that there was sufficient evidence to classify both glyphosate and 2,4-D as human cancer-causing agents. Glyphosate was labeled “probably carcinogenic to humans” and 2,4-D as ‘possibly carcinogenic’.

In reviewing a decade of scientific studies on pesticides, the National Cancer Institute found an association between herbicide exposure and the following types of cancer: non-Hodgkin lymphoma, leukemia, multiple myeloma, prostate cancer, pancreatic cancer, lung cancer, ovarian cancer and soft-tissue sarcoma.

Endocrine System Disruption

According to the Environmental Protection Agency (EPA), both 2,4-D and glyphosate have been linked to the disruption of the endocrine system, which regulates the body’s hormone production. Endocrine disruption has been linked to infertility, low sperm count, birth defects, early puberty, hormone-dependent cancers, like testicular, breast and prostate.

Parkinson’s disease

A 2013 meta-analysis of over 100 studies found that pesticides and solvents are associated with an elevated risk of developing Parkinson’s disease, a neurodegenerative disorder.

Kidney & Liver Disease

Herbicides like glyphosate tend to concentrate in the liver and kidneys, putting these organs at risk for long-term pathologies.

children's health risks

Are children at greater risk than adults to pesticide exposure? Yes, they are at much greater risk, due to their stage of growth and development. Their natural behaviors, such as when babies crawl on the floor or when kids play in the dirt, also up the ante. The National Academy of Sciences, in its 1993 groundbreaking report on pesticide exposure, said it best: “Children are not just little adults.

What determines the nature and level of risk and harm to any given person depends on the timing, dose and toxicity of the pesticide exposure.

  • TIMING: When the exposures occur (e.g., when a woman is pregnant, early in a child’s life, during adulthood, or when a person is fighting a virus or a chronic illness).
  • DOSE: What the level, frequency, and duration of the exposure episode was
  • TOXICITY: The toxicity and properties of the herbicide

In his new book Children and Environmental Toxins*, Dr. Philip Landrigan, pediatrician, epidemiologist, and pioneer in children’s environmental health, explains why timing is critical when it comes to pesticide exposure during childhood. According to Landrigan, the greatest overall danger is that children are undergoing rapid growth, and their delicate developmental processes are easily disrupted.

During childhood, there are ‘windows of vulnerability’ when exposure to even minute amounts of toxic chemicals, exposure that wouldn’t affect the average adult, can result in lifelong injury to the brain, immune system and other organ systems.

Children experience the world in ways that are fundamentally different from adults.  For example:

  • Pound for pound, they breathe in much more air than adults.
  • They are lower to the ground, breathing in pesticide residues in the air or on the floor and carpets, tracked in on clothing and shoes or by household pets.
  • Children also have more permeable skin than adults, and they have more skin surface area in comparison with their overall body weight compared with someone fully grown.
  • They taste, touch and mouth everything they can get their hands on, putting them at greater risk of ingesting toxic material.
  • Their metabolic pathways are immature. Studies show that since their internal organs are still developing they are less able to detoxify chemicals.  It is only at late adolescence that the liver, kidney and GI tract are fully functional.

Pesticide exposure is real.  In its March 2018 report of biomonitoring data on exposures to chemicals, the Centers for Disease Control (CDC) found that children ages 6-11 had significantly higher levels of multiple pesticide residues in their urine than that of adults. Public health experts and epidemiologists have been warning of possible health impacts from pesticide exposure for decades.  Worrisome well-documented pesticide-induced increases in certain childhood cancers (such as leukemia), and neurological disorders and/or loss of IQ have deepened the concern.

Exposure from athletic/playing fields, schools, and playgrounds is of particular concern because of the number of hours children spend on or around such areas.

[*With the authors’ permission, some material has been excerpted from the book, Children and Environmental Toxins by Philip J. Landrigan and Mary M. Landrigan.]