Pat, even though there are other more significant sources of arsenic, the small amounts, IMO, do matter for those of us with mercury issues. Arsenic is excreted (or not) by the same pathways as mercury, and given your likely issues and my known issues, I don't think my body would respond well to even small additional amounts. It's like my son, for example--he's got visible issues from the mercury, so even just a tiny bit more mercury from whatever source (the reason we're not doing seafood right now) would be problematic for him, while a tiny amount for another kid wouldn't be an issue.
And that chicken breast is likely the reason that my daughter's hair test had arsenic out to the red zone.
My years of poor detoxification and eating chicken and probably a lot of other tiny exposures that just added up for me and thus the kids.
Just something to weigh given all our individual circumstances.