Autism research generally falls into one of three categories: cause, treatment or what autistic people want and need, with representation and attention in roughly that order.
The “cause” group in turn splits roughly into environmental and genetic factors. And in the environmental column, we have various candidates from parental age to infections during pregnancy to environmental contaminants. Joining the ranks of “makes you wonder why?” research in this category is a recent study showing a possible link between autism and maternal levels of some persistent pollutants. Pollutants that were in use for almost a century and were banned in the US in 1979.
