Reply #1: This is an interesting report....not good news for the southern rice industry, though.

[MADem]

The large variability in arsenic in different rice strains leads to
considerable uncertainty in estimated exposures for a given mass
of consumed rice. Both the concentration and speciation of arsenic in rice vary with rice cultivar and the arsenic content of the
agricultural soil (16, 17). For example, Williams et al. (17) found
that rice grown in the south-central United States had a substantially higher average total arsenic concentration than rice
grown in California (0.30 vs. 0.17 μg As/g rice). The percentage
of arsenic in rice that is in inorganic forms also has been shown
to vary substantially (21); one study reported rice samples that
ranged from 27 to 86% inorganic arsenic, with the remainder
largely composed of DMA (16). This same study found that the
arsenic in rice grown in the United States was predominantly
DMA, with 42% of the arsenic in inorganic forms (16). Although
inorganic arsenic is thought to be more harmful than DMA (31),
further epidemiological studies are needed to better understand
the health risks of DMA, which is a demonstrated carcinogen in
rats (32). ....