3.3. Human health implication for inorganic As
The predominant arsenic species in samples of CHMs using 1% HNO3 extractionwas inorganic As. Inorganic arsenic concentrations ranged from 62.7 to 550 ng/g (n ¼ 26) with a mean of 208 ng/g in CHMs from fields (Fig.1a) and ranged from 93.5 to 8683 ng/g
(n ¼ 39) with a mean of 1092 ng/g in CHMs from markets or pharmacies (Fig.1b). The Chinese Maximum Contaminant Levels (MCLs) of inorganic As in foods was presented in 2005, such as rice (150 ng/g), wheat flour (100 ng/g), non-staple cereals (200 ng/g)
and vegetables (50 ng/g)(China Food Standard Agency, 2005), not including the maximum limit of inorganic As level for CHMs. If the MCL of inorganic As in non-staple cereal crops (200 ng/g) was referred in this study for the similar growing conditions to
discussion the health risk assessment of inorganic arsenic in CHMs, about 65% of the CHMs from field and 25% of the CHMs from markets or pharmacies would be legal for sale in China; If compared to MCL of inorganic As in vegetables (50 ng/g), inorganic
As concentrations in all of CHMs exceeded this limitation.