The scientific evidence for a link between the toxic chemicals now pervasive in our environment and incidence of autism, ADHD, learning difficulties and developmental delays is rapidly mounting from many countries. Toxic chemicals widely used in agriculture and industry have been linked to developmental delays.
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Children are most vulnerable to toxic chemicals in our air water and food because pound of pound they eat 3-4 times as much food and breathe twice as much air as adults. Many of these chemicals do their worst damage at the time of conception and early pregnancy. The CDC (Center for Disease Control) released data in 2011 from a study in 2003 that included a sample of pregnant women. Known toxins were found in 100% of the women, including DDT which has been banned in the US since the 1970s. These chemicals are saturating our environment and our bodies and appear to be impacting the most vulnerable, our children.

We are providing this information to help you make choices about which chemicals you are willing to expose your family to. At the end of the article we provide resources for more information on how to make choices to limit your own exposure and ways you can take action to help reduce the global toxic load we are all bearing.

pesticides, autism and developmental delays

Pesticides are used to kill insects and plants in agriculture. Pesticides include a variety of harmful chemicals including organophosphates which were originally developed for war fare. They work by disrupting brain and nervous system development in insects and appear to be having similar effects on humans. According to Pesticide Action Network North America each year in the US about 1 billion pounds of pesticides are applied to fields, lawns, forests and golf courses. The map to the right clearly shows that where you live greatly impacts your exposure level.

In 2002 a study of children of men working with glyphosphate (Roundup^®) had a increased risk of birth defects, ADD and hyperactivity. A 2007 study of families in the California Central Valley found that women living close to fields where organophosphates (specifically endosulfan and dicofol) where used during their first trimester of pregnancy were 6 times more likely to have a child later diagnosed with ASD that women who lived elsewhere. The risk factor decreases with distance of residence from the agricultural fields. A 2010 Harvard study published in Pediatrics found that children with above average levels of organophosphate metabolites in their urine with twice a likely to be diagnosed with ADHD. A 2010 study looked specifically at Mexican-American women living in the agricultural regions of California and found an association between maternal levels of pesticide load (measured in their urine) during pregnancy and attention problems in their sons at 5 year of age. Other US studies have linked maternal exposure to pesticides during pregnancy to seriously delayed motor and cognitive development, spatial performance and visual memory, learning rates and increased behavioral problems.


This link between pesticides and neurodevelopmental disorders and delays is not restricted to the US, this is just where most of the research has been done. As early as 1998 researchers from Arizona found startling evidence of serious developmental delay in children in northwestern Mexico. The looked at two villages of Yaqui indians, one in a valley that employed heavy pesticide use in agricultural practices and one from the higher foothills where they did not use pesticides. These children share similar genetic backgrounds, diets, water mineral contents, cultural patterns, and social behaviors. The major difference was their exposure to pesticides. The children in the valley showed decrease stamina, gross and fine hand-eye coordination, 30-minute memory and the ability to draw a person. The results from this last test (shown right) clearly illustrate the degree to which the exposed children were delayed.

Similar results were found in India in a Greenpeace funded study in 2003 investigating the development of children of cotton farmers. India is the third largest producer of cotton in the world with the largest amount of land dedicated to cotton (19% of the world's total). Even so this huge land mass still only accounts for 5% of the total land mass under agriculture in India. The cotton fields however consume 50% of India's pesticides. 70% of Indian cotton farms are run by individual families. They often have to spend 5 times as much money on pesticides as they do on seeds as weeds and insects are becoming more and more resistent to the chemicals - most of which are designated as hazardous by the World Health Organization. The study reveals serious mental development disorders that range from severely impaired analytical abilities, motor skills, concentration and memory among the children in the chemical-intensive cotton belts of India.

other toxic chemicals, autism and developmental delays

Five known mutagens have been linked to increased risk for autism specifically, mercury (from incineration and coal burning), cadmium, nickel, trichloroethylene, and vinyl chloride.

A 2009 study in Texas. This study found that autism prevalence increased 2.6% for every 1,000 pounds of mercury released in the vicinity of the geographical center of a given district, and 3.7% with nearby power plant emissions. The closer a child lived to a coal burning power plant the more likely they were to be diagnosed with autism. A 2006 study in San Fransisco took 284 children with autism and found out what the hazardous air pollutant (HAP) concentrations compiled by the U.S. Environmental Protection Agency were for the place each of these children was born. They found a strong link between exposure to air born mercury, cadmium, nickel, trichloroethylene, and vinyl chloride and autism.

Bisphenol A (BPA) is a chemical used to make epoxy resin to line food cans and other containers, it is the building block for polycarbonate plastic and is present in paper products. It has been linked to externalizing behavior ("acting out") in children.

Lead is a heavy metal used in industry it is present in many products including electronics, PVC plastics and cosmetic. It has been shown to damage brain tissue and has been linked to antisocial behavior and ADHD.

PBDEs are Polybrominated diphenyl ethers, a class of flame retardant chemicals used in construction, electronics and furniture upholstery. They have been linked to impaired fine motor skills and attention. The authors of this 2009 study conclude "Our results demonstrate for the first time that transplacental transfer of polybrominated flame retardants is associated with the development of children at school age. Because of the widespread use of these compounds, especially in the United States, where concentrations in the environment are four times higher than in Europe, these results cause serious concern."