T2. He is only like 11 years old. So I think he was exercising enough, in terms of he plays a bunch of sports.
If there is some kind of direct damage occuring to hormonal systems then it doesn't really have to correlate to weight and exercise related T2.
The roads of my childhood were definitely included higher polluting diesel trucks, but kids and pregnant women did spend a lot less time traveling and usually didn't ride in diesel vehicles themselves, there was that fine leaded gas..