Metals are one of the most frequent mentioned environmental factor being related to the onset of autism. Among metals, mercury (Hg) and lead (Pb) are most often investigated in relation to autism. Both were shown to be related to the incidence of autism and even have a suggested dose-dependent effect on the severity of the autistic symptoms.
Both mentioned metals are capable to pass through the placenta, the blood brain barrier and have the ability of affecting critical developmental processes. Thereby, these heavy metals have the potential to influence the fetus already at a prenatal stage, possibly increasing the risk to develop autism.
Other heavy metals suspected to be involved in the etiology of autism are aluminum, cadmium and arsenic.

It is believed that a decreased excretion ability, rather than high exposure, is responsible for the development of ASD. This low excretion/ detoxification ability in autistic patients was investigated by Alabdali et al. (2014), who found a lower glutathione (GSH) level in autistic individuals. GSH is important in many different processes, such as the detoxification of mercury.

Most often, studies analyze metal levels in individuals of at least 3 years of age. However, prenatal exposure to certain metals might be of relevance for the onset of autism.

I aim with this study to investigate metal exposure at a prenatal stage and relate those findings with the diseases autism, serum positive rheumatoid arthritis (ANA) and diabetes.