I wonder if arsenic in rice is even a true concern. Billions of people across Asia eat it as staple food and the incidence of cancer is usually lower (could be due to low reported cases though).
Not sure about Bangladesh, but arsenic was commonly used as an insecticide in US rice fields in the south, so rice from that region still has some of the highest arsenic concentrations on earth.
In the US rice is less of a staple food (except for infants), so it matters less, I guess.
If it's that way around it's likely to matter more, infants tend to be far more sensitive to toxins than adults. Specifically it can seriously affect brain development, same with lead.