Findings Show Mercury During the Postnatal Period Is Especially Harmful
A recent systematic review has underscored the role of mercury (Hg) exposure in the onset of autism spectrum disorder (ASD), particularly when such exposure occurs during the postnatal period. According to the findings, infants are highly susceptible to toxins and heavy metals like Hg during the postnatal phase, potentially leading to neurological impairment and DNA damage. The review further revealed elevated levels of Hg in the blood, hair, and urine of children diagnosed with ASD who were exposed to environments with heightened Hg pollution in air and water. This increase in Hg levels may be attributed, in part, to compromised glutathione (GSH) antioxidant mechanisms and deficiencies in metallothionein (MT) proteins, which are responsible for the elimination of toxic metals from the body. Failure to excrete metals properly can result in heightened oxidative stress and inflammation, exacerbating autism symptoms. Additionally, the review highlights the impact of oral antibiotic use on altering intestinal flora, leading to the conversion of Hg into methylmercury (MeHg), a potent neurotoxin capable of crossing physiological barriers and causing developmental and neurological damage. Notably, many infants later diagnosed with ASD have a history of oral antibiotic intake. The authors acknowledge the controversial nature of their findings, as some studies in the review found a positive correlation between Hg levels and autism, while others did not. To further elucidate Hg’s impact during pre- and post-natal periods, the authors advocate for pre-clinical research using ASD animal models to investigate associated brain changes. They also emphasize the importance of studying the altered excretory systems observed in individuals with autism.