NCTR Research Highlights

Periodic report on research activities and special events at NCTR

2025 Research Highlights

Regulatory Impact of NCTR Research—Additives and Contaminants

January 13, 2025

Regulatory Impact of NCTR Research—Additives and Contaminants

Food Additives

Brominated vegetable oil (BVO) has been used as a food additive in citrus beverages to prevent citrus oils from floating to the top of the beverages. Previously conducted toxicological studies—in close collaboration with FDA’s Human Foods Program (HFP) under an Interagency Agreement with the National Institute of Environmental Health Sciences’ Division of Translational Toxicology—to clarify specific outstanding questions on the toxicological profile of BVO resulted in multiple publications (10.1016/j.foodchem.2016.06.110; 10.1016/j.jchromb.2020.122415; 10.1016/j.fct.2022.113137). The outcome of these studies contributed to FDA’s conclusion that the intended use of BVO in food was no longer considered safe and prompted the agency to revoke the authorization to use BVO in food in July 2024. NCTR’s work was referenced in the final rule.

Ink Contaminants

An FDA guidance for industry—Insanitary Conditions in the Preparation, Packing, and Holding of Tattoo Inks and the Risk of Microbial Contamination—was published in October 2024 to help tattoo ink manufacturers and distributors recognize and prevent situations in which tattoo or permanent makeup (PMU) inks may become contaminated. Cited in the guidance background was an NCTR study on commercial tattoo and PMU inks.

A high prevalence of tattoo complaints, including photosensitivity, have been reported among individuals tattooed with Carbon Black and organic red pigments, with the latter provoking more reports of adverse reactions. In the U.S., FDA regulates tattoo inks as cosmetics, while pigments are regulated as color additives. Given the potential hazards, the Office of Cosmetics and Colors (OCAC) has raised concerns and is collaborating with NCTR to investigate the deposition and biodistribution of Pigment Red 22 and Carbon Black inks into the skin in a human-relevant model.

Environmental Contaminants

6PPD is a chemical that prevents automotive tires from degrading. It reacts with ozone to form 6PPD-Quinone (6PPD-Q), which is washed into bodies of water via rainwater/runoff. 6PPD-Q toxicity was linked to coho salmon death, prompting inquires on whether consumption of exposed fish might pose a human health risk. In collaboration with HFP, NCTR began conducting work in early 2023 and reported that, based on their findings, 6PPD-Q does not appear to pose a human liver health risk at the current exposure levels. These findings were presented in 2024 at the MPS World Summit and the Society of Toxicology annual meeting.