3-CHLORO-1,2-PROPANEDIOL

Comments:

No genotoxic potential has been demonstrated in vivo for 3-MCPD. Two long-term carcinogenicity studies with 3-MCPD in rats were identified as pivotal studies, and renal tubular hyperplasia was identified as the most sensitive end-point. The lowest BMDL10 for renal tubular hyperplasia was calculated to be 0.87 mg/kg bw per day for male rats. After application of a 200-fold uncertainty factor, the Committee established a group PMTDI of 4 µg/kg bw for 3-MCPD and 3-MCPD esters singly or in combination (expressed as 3-MCPD equivalents). The overall uncertainty factor of 200 incorporates a factor of 2 related to the inadequacies in the studies of reproductive toxicity. The previous PMTDI of 2 µg/kg bw for 3-MCPD, was withdrawn. The Committee noted that estimated dietary exposures to 3-MCPD for the general population, even for high consumers (up to 3.8 µg/kg bw per day), did not exceed the new PMTDI. Estimates of mean dietary exposure to 3-MCPD for formula-fed infants, however, could exceed the PMTDI by up to 2.5-fold for certain countries (e.g. 10 µg/kg bw per day in the first month of life).

Tolerable Intake:

PMTDI of 4 µg/kg bw for 3-MCPD and 3-MCPD esters singly or in combination

Meeting:

83

Report: 

Tox Monograph: 

Comments:

As no new pivotal toxicological studies had become available the Committee retained the previously established PMTDI of 2 µg/kg bw for 3-chloro-1,2-propanediol. This PMTDI was established based on a LOEL of 1.1 mg/kg bw/d from a drinking water carcinogenicity study in Fischer/344 rats and a safety factor of 500. Estimated exposures at the national level considered a wide range of foods, including soy sauce and soy-sauce related products, ranged from 1% to 35% of the PMTDI for average exposure in the general population. For the consumers at the high percentile (95th), the estimated intakes ranged from 3% to 85% and up to 115% of the PMTDI in young children. These estimates are based on concentrations of 3-chloro-1,2-propanediol derived before any remedial action had been taken by government or industry. The Committee noted that reduction in the concentration of 3-chloro-1,2-propanediol in soy sauce and related products made with acid-HVP could substantially reduce the intake of this contaminant by certain consumers of this condiment.

Intake:

population mean: 0.7 µg/kg bw/d; 95th-percentile intake: 2.3 µg/kg bw/d, estimates include young children. Consumption of some highly-contaminated products could result in intakes exceeding the PMTDI.

Tolerable Intake:

PMTDI 2 µg/kg bw/d

Meeting:

67

Report: 

Tox Monograph: 

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