>I question whether measuring excreted compounds rather than stores is relevant I would have to figure that chemicals sitting in fat cells that rarely divide a

>I question whether measuring excreted compounds rather than stores is relevant I would have to figure that chemicals sitting in fat cells that rarely divide are probably not causing cancer. Cancer occurs mostly in epithelial tissue; in my case, the germ cell. Excreted compounds are probably a better measure of actual blood levels. I'm not a nephrologist or anything, though. >A small prospective study will almost certainly find nothing, because the rate of early-onset cancer is too low to detect changes in a small population. You probably need >100k participants to have a good chance of finding anything. >it is unclear what value this information will provide I mean, that's the billion-dollar question, isn't it? Should probably try to control for obesity first, it's the most obvious candidate (changes since 1990, so not, e.g., smoking), but it certainly wasn't my problem (BMI 21).