Their environmental contaminant hypothesis is very interesting and seems like it could be further confirmed or disproved with more data. Can we link childhood

Their environmental contaminant hypothesis is very interesting and seems like it could be further confirmed or disproved with more data. Can we link childhood obesity to areas with particularly high rates of some kind of industrial contamination? (Poverty as a confounding effect may make this hard) If the watershed is part of the mechanism, can we confirm lower obesity rates in areas without much industrial pollution that have similar diet & exercise to obese areas? (Independent of the already-mentioned altitude effects)