Department of Ecology | 6-ETHOXY-2,2,4-TRIMETHYL-1,2-DIHYDROQUINOLINE (ETHOXYQUIN) (CAS #91-53-2) Greenscreen® For Safer Chemicals (Greenscreen®) Assessment

Executive Summary: 6-Ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline (Ethoxyquin) is a quinoline organic compound with an ethoxy substituent that is used in animal feed as an antioxidant and is permitted as an anti-scald agent on apples and pears with a residue tolerance of 3 ppm (40 CFR § 180.178) and as a direct food additive (21 CFR § 172.140). The United States Food and Drug Administration (U.S. FDA) has established a tolerance of 0.5 ppm for residues of ethoxyquin in or on uncooked meat and meat by-product (including milk and eggs) and 5.0 ppm for cooked meat and meat by-products of animals fed forage crops or feed supplements treated with ethoxyquin. Ethoxyquin is used as a color preservative in spices and as an anti-degradation agent for rubber. Ethoxyquin is a yellow to brown liquid at standard temperature and pressure, not highly volatile, and is slightly soluble in water.

Ethoxyquin was assigned a GreenScreen Benchmark™ Score of 2 (“Use but Search for Safer Substitutes”).