What do studies show about the levels of 1,4-dioxane in shampoos and bubble baths?

Note: Much of the information in this section is from: Black RE, Hurley FJ, Havery DC. 2001. Occurrence of 1,4-dioxane in cosmetic raw materials and finished cosmetic products. J AOAC Int 84(3):666–670.

1979: 1,4-Dioxane identified in raw materials used in the manufacture of cosmetic productsIn 1979–1980, the FDA urged the cosmetic industry to monitor their raw materials for 1,4-dioxane.
1980s-Downward trend in levels of 1,4-dioxane.The results of surveys suggested a downward trend in the levels of 1,4-dioxane in cosmetic finished products analyzed between 1981 and 1984. Changes in the manufacturing process may be responsible for the apparent trend. FDA surveys were then suspended in 1984 but were resumed in 1992.
1990s-Levels increaseNinety-nine products were analyzed between 1992 and 1997. The products analyzed since 1994 focused on children’s shampoos because the process used in their manufacturing was linked to 1,4-dioxane. The downward trend in the levels of 1,4-dioxane previously observed in products analyzed in the 1980s was no longer evident in the products analyzed in the 1990s. Of particular concern were levels of 1,4-dioxane observed in children’s shampoos analyzed in 1994/95 manufactured by two companies. 1,4-Dioxane was frequently present at levels in excess of 85 ppm.

From: APPENDIX D, HEALTH ADVISORY

Cover of Toxicological Profile for 1,4-Dioxane
Toxicological Profile for 1,4-Dioxane.
Wilbur S, Jones D, Risher JF, et al.

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