Dimethylarsinic Acid (DMA(V)): Increased incidence of urinary bladder tumours in rats was identified as the critical endpoint. A Benchmark Dose Lower Confidence Limit (BMDL10) of 1.1 mg DMA(V)/kg body weight (bw) per day (equivalent to 0.6 mg As/kg bw per day) was calculated as a reference point (RP).
Monomethylarsonic Acid (MMA(V)): Decreased body weight resulting from diarrhea in rats was identified as the critical endpoint. A BMDL10 of 18.2 mg MMA(V)/kg bw per day (equivalent to 9.7 mg As/kg bw per day) was calculated as an RP.
Occurrence data for small organoarsenic species were available only for MMA and DMA, all reported as pentavalent species. The dataset for dietary exposure estimates included 1260 analytical results for DMA and 988 for MMA, all expressed in whole weight and as μg As/kg.
MMA(V): An MOE of ≥ 500 does not raise a health concern. All MOEs were well above 500 for average and high consumers.
DMA(V): An MOE of 10,000 is considered of low health concern due to its genotoxic and carcinogenic potential. However, MOEs were below 10,000 in many cases across dietary surveys and age groups, particularly for some 95th percentile exposures, raising health concerns.
The CONTAM Panel identified a need for:
By addressing these gaps, a more comprehensive health risk assessment for small organoarsenic species in food can be achieved.