The relationship between mercury and autism spectrum disorders (ASD) has always been a topic of controversy among researchers. A recent 2017 study aimed to assess the relationship between ASD and mercury levels in hair, urine, blood, red blood cells (RBC), and brain through a meta-analysis.
A search of several databases up to June 2017 to find case-control studies evaluating the concentration of total mercury in different tissues of ASD patients and comparing them to the healthy subjects (control group) was done.
The results came up with a total of 44 studies that met the necessary criteria for meta-analysis. The mercury level in whole blood, RBC and brain were significantly higher in ASD patients than healthy subjects, whereas mercury level in hair was significantly lower in ASD patients than healthy subjects.
The mercury level in urine was not significantly different between ASD patients and healthy subjects.
The results of the current meta-analysis revealed that mercury is an important causal factor in the etiology of ASD. It seems that the detoxification and excretory mechanisms are impaired in ASD patients which lead to accumulation of mercury in the body.
Tina Jafari, Noushin Rostampour, Aziz A Fallah, Afshin Hesami. The association between mercury levels and autism spectrum disorders: A systematic review and meta-analysis. J Trace Elem Med Biol. 2017 Dec ;44:289-297. Epub 2017 Sep 4. PMID: 28965590