[Some] women show widespread exposure to environmental toxins—and levels are often even higher in their newborn babies.
Source: Mom’s exposure to toxic chemicals shows up in newborn – Futurity
It is easy to postulate that some of these herbicides and insecticides have a higher incorporation in growing cells. This would explain the higher levels in infants but it would also suggest a likely impact on our immune systems since our immune systems require growing cells.
The sloppiness of herbicide toxicity studies by the big chemical companies is criminal in my opinion. I can grow much of what I eat and a pond or swimming pool converted to non-chlorine is a great food resource.