Formaldehyde has been classified as carcinogenic to humans by International Agency for Research on
Cancer and found in personal care (PC) products containing
formaldehyde-donor (FD) preservatives. However, the
cancer risk associated with the use of FD-containing PC products has not been well established. Our study provides the quantitative
cancer risk assessment of
formaldehyde in FD-containing PC products. The
carbon-13 nuclear magnetic resonance (13C-NMR) spectroscopy was used in this risk assessment to provide reliable exposure information to
formaldehyde in PC products and aqueous solutions containing
sodium hydroxymethylglycinate. The risk assessment was conducted using the margin of exposure (MOE) approach with benchmark doses (BMDs) for 10% effect. For hemolymphoreticular
neoplasias in male rats, a BMD of 28.03 mg/kg/day and a BMD lower confidence limit (BMDL) of 2.52 mg/kg/day were calculated from available long-term animal experiments. The worst-case consumer exposure to
formaldehyde from FD-containing PC products was 0.007 μg/kg/day. Comparing the consumer exposure with BMDL, the resulting MOE was 360,000 for the worst-case scenario. The consumer exposure to
formaldehyde (0.007 μg/kg/day) from using FD-containing PC products represents less than 1.0 × 10-6 % of background level endogenous
formaldehyde (878-1310 mg/kg/day). The
cancer risk from
formaldehyde to consumers using FD-containing PC products is negligible.