In the face of NGO objections, the US EPA is sticking to its decision not to include the occurrence of 1,4-dioxane as a contaminant in consumer products in its forthcoming TSCA risk evaluation of the substance.

The substance 1,4-dioxane is used primarily as a solvent in a variety of industrial and commercial applications, but it also occurs as an unintentional contaminant in consumer products containing ethoxylated surfactants, including shampoos, detergents and cosmetics.

The TSCA’s position was criticized when it was initially outlined in the substance’s ‘scope’ document – there are concerns that leaving it out of the risk evaluation could result in lower exposure estimates for human populations and lower estimates of risks to human health. However, the EPA has confirmed its approach in the substance’s draft problem formulation, saying that “contamination of industrial, commercial and consumer products are not intended conditions of use for 1,4-dioxane and will not be evaluated”.

The EPA said in its scope that it would not include this occurrence in its risk evaluation because it “anticipates that 1,4-dioxane byproduct and contaminant issues will be considered in the scope of any risk evaluation of ethoxylated chemicals”.