Autism and Mercury Exposure

Mercury toxicity and autism share several symptoms, including social impairments, depression, anxiety, and neurosis.

There is now evidence that autism can be caused by a biochemical abnormality that disables the metal clearing function of metallothionein (MT) protein. MT protein works in concert with zinc to eliminate mercury and other heavy metals from the body. Severe zinc depletion and toxic metal overload may disable MT function. It has become clear that zinc depletion actually leads to toxic metal overload, and that mercury exposure causes zinc depletion. Zinc deficiency also plays a role in ADHD.

Long term exposure to mercury contaminated high fructose corn syrup could cause both zinc depletion and toxic metal overload, compromising MT functioning and leading to the bioaccumulation of mercury. ¹

Several environmental and epigenetic studies have found links between mercury exposure and compromised neurological function, including autism.

For every 1,000 pounds of mercury released into the environment, there was a 43-percent increase in the rate of special education services and a 61-percent increase in the rate of autism.²

Low zinc intake during pregnancy is associated with a significant increase in the risk of preterm delivery ³. Low birth weight and pre-term birth increase the risk of autism two fold.⁴

In a study on prenatal mercury exposure in the Faroe Islands, researchers found after following 900 children until seven years of age that higher umbilical cord blood methylmercury was associated with lower scores on several developmental and cognitive tests [38]. The Faroese diet includes whale meat. In whale meat, the concentration of mercury rises continually with age and can exceed the selenium content. ⁵

Another study on prenatal mercury exposure followed 700 children in the Seychelles Islands, and found no relation between maternal hair mercury content and neurological function. This may be because Selenium levels are lower than mercury content in whale meat. Selenium is an important micronutrient which protects neurons from damage caused by mercury. ⁵ The Faroese diet of whale meat most likely contains more unmitigated mercury exposure with lower levels of selenium. ¹

• Polluted air, soil, dust, and water caused by
  • mercury mining and ore processing
  • coal combustion for power production
  • chlor-alkali industries ¹
• Fish and seafood
  • As of 2009, the most contaminated fish included king mackerel, swordfish, shark and tilefish ¹
• Common food ingredients such as
  • High Fructose Corn Syrup (HFCS)
  • Food colorings
  • Thimerosal, a preservative found in vaccines

¹ Dufault, Renee et al. "Mercury exposure, nutritional deficiencies and metabolic disruptions may affect learning in children," Behavioral and Brain Functions 5, no 44 (2009). ² Palmer, R et al. “Environmental mercury release, special education rates, and autism disorder: an ecological study of Texas.” Health Place 12, 203-209: (2006).

³ Scholl TO et al. “Low zinc intake during pregnancy: its association with preterm and very preterm delivery.” American Journal of Epidemiology 10 no 137, 1115-1124:(1993).

⁴ Schendel D et al. “Birth weight and gestational age characteristics of children with autism, including a comparison with other developmental disabilities.” Pediatrics 6, no 121: 1155-1164 (2008).

⁵ Julshamn K et al. “Trace elements intake in the faroe islands - element levels in edible parts of pilot whales (globicephalus meleanus).” Sci Total Environ 65: 53-62 (1987).