Heavy metals: Heavy metals like lead, mercury, and cadmium can be found in air, water, soil, and food, and exposure to these metals can cause a variety of health problems. For example:

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• The Centers for Disease Control and Prevention (CDC) states that there is no safe level of lead exposure, and even low levels of exposure can cause developmental problems in children. (https://www.cdc.gov/nceh/lead/prevention/sources/leadinair.htm)

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• A study published in Environmental Health Perspectives found that prenatal exposure to mercury was associated with a higher risk of ADHD in children. (https://ehp.niehs.nih.gov/doi/10.1289/ehp.1307922)

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• A review of the scientific literature published in Environmental Health Perspectives found that exposure to cadmium was associated with an increased risk of lung cancer, kidney disease, and other health problems. (https://ehp.niehs.nih.gov/doi/10.1289/ehp.1002384)

 

 

 

 

Here are a few studies that investigate the relationship between heavy metal exposure and autism spectrum disorder:

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• Kern JK, Geier DA, Audhya T, et al. A prospective study of prenatal mercury exposure from maternal dental amalgams and autism severity. Acta Neurobiol Exp (Wars). 2012;72(2):113-121.

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• Li Y, Jing P, Lin H, et al. Elevated levels of urinary heavy metals in children with autism spectrum disorder. J Trace Elem Med Biol. 2019;56:90-97.

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• Rahbar MH, Samms-Vaughan M, Loveland KA, et al. Maternal and environmental risk factors for autism spectrum disorders in a high-risk Latino population. J Autism Dev Disord. 2012;42(11):2432-2443.

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• Windham GC, Zhang L, Gunier R, et al. Autism spectrum disorders in relation to distribution of hazardous air pollutants in the San Francisco Bay Area. Environ Health Perspect. 2006;114(9):1438-1444.

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• Zahir F, Rizwi SJ, Haq SK, et al. Low dose mercury toxicity and human health. Environ Toxicol Pharmacol. 2005;20(2):351-360.

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It's worth noting that the studies investigating the relationship between heavy metal exposure and ASD have produced mixed results, with some studies finding an association and others not. The field is still actively being researched and debated, and further studies are needed to fully understand the relationship between heavy metal exposure and ASD.

 

While it is not clear exactly how heavy metal exposure may contribute to the development or exacerbation of ASD, one proposed mechanism is through oxidative stress. Heavy metals are known to generate reactive oxygen species (ROS), which can cause cellular damage and inflammation. Additionally, heavy metals may interfere with important cellular processes and disrupt the normal functioning of the brain.