Chemical exposures found to be associated with ADHD
Published in the Walla Walla Family Forum, a Supplement of the Walla Walla Union Bulletin December/January 2019
According to the Center for Disease Control (CDC), millions of children have been diagnosed with Attention Deficit Hyperactivity Disorder (ADHD). It has been found that pre-natal or post-natal exposure to the toxins listed below have been shown to increase the risk of ADHD. Some of these are chronic, low-dose exposures prevalent to modern life:
Polychlorinated Biphenols (PCBs): PCBs were banned for use in the United States in 1979 due to their inability to break down. They have persisted in our environment and the most common source of exposure today is in farm-raised salmon. They are fat-soluble, so they can also be found in fatty animal products such as butter. One study showed that Massachusetts children whose mothers resided near a harbor contaminated with PCBs were 78% more likely to have ADHD-related learning problems by 11 years of age.
Methylmercury (MeHg): MeHg exposure most often comes from consumption of large fish such as king mackerel, shark, orange roughy, swordfish, or ahi tuna. A study published in Environmental Health Perspectives found women with a hair mercury level above 1 mcg/g during pregnancy were more likely to have a child with elevated inattentiveness and impulsivity.
High Molecular Weight (HMW) Phthalates: These are plasticizers that are found in plastic shower curtains, raincoats, vinyl flooring, plastic food wrap and furniture polishes. Prenatal exposure to HMW phthalates was found to be associated with delinquent and aggressive behavior in 8-year-olds in a Taiwanese study.
Lead: The most common exposure sources of lead in children today are lead-based paints and contaminated drinking water related to leaching from lead pipes. Lead-based paints were banned in 1978, so older homes present a higher risk. The CDC uses a blood lead reference value of 5 micrograms per deciliter (mcg/dL) to identify a level of concern of lead exposure in children. However, children with blood lead levels (BLLs) as low as 1.4-2.0 mcg/dL have been found be 2.7 times more likely to have ADHD than those with BLL less than 0.7 mcg/dL. Children with BLLs >2.0 mcg/dL had four times the risk of having ADHD.
Pyrethroid insecticides: These are commonly used residentially and commercially. Children between the ages of 6 and 15 with detectable urinary levels of pyrethroid metabolites where twice as likely to have a diagnosis of ADHD.
Organophosphate pesticides (OPs): These are the most commonly used insecticides in agriculture today. CDC data has revealed a significant association between the presence of urinary OP metabolites and the diagnosis of ADHD.
Glyphosate-based herbicides (GBHs): GBHs are the most commonly used residential and agricultural herbicides in the United States. According to a 2016 article in Newsweek, nearly 300 million pounds of glyphosate are applied to farms each year in America. One study showed that children of male farm workers who applied GBHs were 3.6 times more likely to have a diagnosis of ADD or ADHD.
The CDC has been collecting a substantial amount of data on many toxins through their National Health and Nutrition Examination Survey (NHANES). The NHANES database is public information and can be found at www.cdc.gov/exposurereport/index.html. Glyphosate has not yet made it into the NHANES data, but the rest of the toxins listed above, as well as many others, have been included. Clinically, we are now able to test for many common toxins or their metabolites to determine current levels of exposure.
ADHD is just one of many conditions now linked to chronic, low-dose exposure of toxins. There are many ways to assist your body in eliminating these toxins. However, the best way to protect yourself and your family is to identify potential exposure sources and then mitigate them appropriately.
Crinnion, W., and Pizzorno, J. E. (2019). Clinical environmental medicine: Identification and natural treatment of diseases caused by common pollutants. St. Louis, Missouri: Elsevier.
Dr Julie Figgins is a licensed naturopathic physician, trained at Bastyr University in Seattle. She owns and operates Julie Figgins ND in Walla Walla and Ellensburg. Additionally, she is lecturer of Environmental Medicine in the Clinical Sciences department at National University of Health Sciences in Lombard, Illinois.