Ethoxylation is the process of reacting ethylene oxide with other chemicals to make them less harsh. Ethoxylation can create small amounts of 1,4-dioxane and leave residual ethylene oxide in the product.

FOUND IN: shampoo, liquid soap, bubble bath, hair relaxers.

WHAT TO LOOK FOR ON THE LABEL: PPG, PEG, polysorbate and ingredients that end in –eth such as laureth, steareth, ceteareth.

WHAT ARE ETHOXYLATED INGREDIENTS? Ethoxylated ingredients on their own are of low concern, however, the process of ethoxylation, may leave behind trace amounts of carcinogens.

1,4-dioxane is a clear liquid that easily dissolves in water. It is used primarily as a solvent in the manufacture of chemicals and as a laboratory reagent.[1] Ethylene oxide is a man-made chemical that is used primarily to make ethylene glycol and sometimes used in hospitals to sterilize medical equipment and supplies.[2]

HEALTH CONCERNS: This manufacturing process can result in two toxic contaminants linked to breast cancer and other cancers: ethylene oxide and 1,4-dioxane.

In our 2016 report focusing on kids’ makeup products we found 28% of products listed ethoxylated ingredients on their labels.[3] Ethoxylated ingredients are generally of low concern on their own. However, they can be contaminated with ethylene oxide, a known carcinogen,[4] and 1,4- dioxane, reasonably anticipated to be a human carcinogen by the NTP.[5] MORE...

Ethoxylated ingredients are listed on labels, but without testing them, there is no way to know if a product contains residual ethylene oxide or 1,4 dioxane.

Cancer: Research shows that 1,4-dioxane readily penetrates the skin.[6] 1,4-dioxane is listed as possibly carcinogenic to humans by the International Agency for Research on Cancer (IARC).[7] It is included on California’s Proposition 65 list of chemicals known or suspected to cause cancer or birth defects.[8]

Ethylene oxide is classified as a known human carcinogen by IARC[9] and listed on California’s Proposition 65 list of chemicals known or suspected to cause cancer.[10] Lymphoma and leukemia are the cancers most frequently to be associated with occupational exposure to ethylene oxide.[11] Data also link ethylene oxide to breast cancer.[12],[13],[14],[15]

Reproductive toxicity: Ethylene oxide is listed on Prop 65 list as a developmental toxicant and a male and female reproductive toxicant.[16] Other reviews have found ethylene oxide to be a reproductive toxin in male and female rats resulting in decreased fertility, increased fetal deaths, and heritable chromosomal translocations.[17] A study found that inhalation of ethylene oxide at low concentrations affected the development of sperm in rats.[18]

Other: Short-term exposure to 1,4-dioxane may result in nausea, drowsiness, headache, and irritation of the eyes, nose and throat.[19],[20],[21] Long-term exposure may result in dermatitis, eczema, drying and cracking of skin  and liver and kidney damage.[22],[23]

VULNERABLE POPULATIONS: Everyone, especially pregnant women, infants, teenagers.

REGULATIONS: 1,4-dioxane and ethylene oxide are prohibited for use in cosmetics products in Canada.[24] The European Union has also prohibited use of ethylene oxide in cosmetic products.[25]

The FDA does not require 1,4-dioxane or ethylene oxide to be listed on ingredient labels because both are contaminants of manufacturing.[26]

HOW TO AVOID: Since labels do not indicate the presence of these contaminants, check labels for the presence of chemicals with PPG, PEG, and polysorbate in their name and ingredients that end in –eth such as laureth, steareth, ceteareth. Some companies have policies to strip the contaminants, so if your favorite product has one of these, check the company website or call them to see if they have a policy.

References

[1] ATSDR: Agency for Toxic Substances & Disease Registry. Toxic substances portal – 1,4-dioxane. ToxFAQs. Available online: http://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=954&tid=199

[2] ATSDR: Agency for Toxic Substances & Disease Registry. Toxic substances portal – ethylene oxide. ToxFAQS. Available online: http://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=733&tid=133

[3] Engel C, Nudelman MA, Rasanayagam S, Witte M. Pretty Scary 2 Unmasking toxic chemicals in kids’ makeup. Campaign for Safe Cosmetics. 2016 Oct. Available online:  http://www.safecosmetics.org/wp-content/uploads/2016/10/Pretty-Scary_2016.pdf

[4] NTP (National Toxicology Program). 2014. Report on Carcinogens, Fourteenth Edition. Research Triangle Park, NC: U.S. Department of Health and Human Services, Public Health Service. http://ntp.niehs.nih.gov/ntp/roc/content/profiles/ethyleneoxide.pdf

[5] NTP (National Toxicology Program). 2014. Report on Carcinogens, Fourteenth Edition. Research Triangle Park, NC: U.S. Department of Health and Human Services, Public Health Service. http://ntp.niehs.nih.gov/ntp/roc/content/profiles/dioxane.pdf

[6] Spath, D.P.  “1,4-Dioxane Action Level.”  March 24, 1998.  Memorandum from Spath, Chief of the Division of Drinking Water and Environmental Management, Department of Health Services, 601 North 7th Street, Sacramento, California 95814 to George Alexeeff, Deputy Director for Scientific Affairs, Office of Environmental Health Hazard Assessment. Available online:  http://www.oehha.ca.gov/water/pals/pdf/PAL14DIOXAN.pdf

[7] IARC: International Agency for Research on Cancer. IARC monographs. 1,4-dioxane. Available online: http://monographs.iarc.fr/ENG/Classification/ClassificationsAlphaOrder.pdf

[8] Office of Environmental Health Hazard Assessment (OEHAA) (2016). State of California Environmental Protection Agency. Chemicals known to the state to cause cancer or reproductive toxicity. Available online:  http://oehha.ca.gov/proposition-65/chemicals/14-dioxane

[9] IARC: International Agency for Research on Cancer. IARC monographs. Ethylene Oxide. Available online: http://monographs.iarc.fr/ENG/Classification/ClassificationsAlphaOrder.pdf

[10] Office of Environmental Health Hazard Assessment (OEHAA) (2016). State of California Environmental Protection Agency. Chemicals known to the state to cause cancer or reproductive toxicity. Available online:  http://oehha.ca.gov/proposition-65/chemicals/ethylene-oxide

[11] NIH: National Institutes of Health. National Cancer Institute. Ethylene Oxide. 2015. Available online: https://www.cancer.gov/about-cancer/causes-prevention/risk/substances/ethylene-oxide

[12] Rudel RA, Attfield KR, Schifano JN, Brody JG. Chemicals causing mammary gland tumors in animals signal new directions for epidemiology, chemicals testing, and risk assessment for breast cancer prevention. Cancer. 2007;109:2635-66.

[13] Steenland K, Whelan E, Deddens J, Stayner L, Ward E. Ethylene oxide and breast cancer incidence in a cohort study of 7576 women (United States). Cancer Causes Control. 2003;14:531-9.

[14] Norman SA, Berlin JA, Soper KA, Middendorf BF, Stolley PD. Cancer incidence in a group of workers potentially exposed to ethylene oxide. Int J Epidemiol. 1995;24:276-84.

[15] Mikoczy Z, Tinnerberg H, Björk J, Albin M. Cancer Incidence and Mortality in Swedish Sterilant Workers Exposed to Ethylene Oxide: Updated Cohort Study Findings 1972–2006. Inl J Environ Res Public Health. 2011;8:2009-19.

[16] Office of Environmental Health Hazard Assessment (OEHAA) (2016). State of California Environmental Protection Agency. Chemicals known to the state to cause cancer or reproductive toxicity. Available online:  http://oehha.ca.gov/proposition-65/chemicals/ethylene-oxide

[17] Landrigan PJ, Meinhardt TJ, Gordon J, Lipscomb JA, Burg JR, Mazzuckelli LF, Lewis TR, Lemen RA. Ethylene oxide: an overview of toxicologic and epidemiologic research. American journal of industrial medicine. 1984 Jan 1;6(2):103-15.

[18] Mori K, Kaido M, Fujishiro K, Inoue N, Koide O, Hori H, Tanaka I. Dose dependent effects of inhaled ethylene oxide on spermatogenesis in rats. British journal of industrial medicine. 1991 Apr 1;48(4):270-4.

[19] Agency for Toxic Substances and Disease Registry (ATSDR). 2012. “Toxicological Profile for 1,4-Dioxane.” www.atsdr.cdc.gov/toxprofiles/tp187.pdf

[20] EPA. 2013b. “1,4-Dioxane (1,4-Diethyleneoxide).” Technology Transfer Network Air Toxics Website. www.epa.gov/ttnatw01/hlthef/dioxane.html

[21] National Institute for Occupational Safety and Health (NIOSH). 2010. “Dioxane.” NIOSH Pocket Guide to Chemical Hazards. www.cdc.gov/niosh/npg/npgd0237.html

[22] Agency for Toxic Substances and Disease Registry (ATSDR). 2012. “Toxicological Profile for 1,4-Dioxane.” www.atsdr.cdc.gov/toxprofiles/tp187.pdf

[23] HSDB Hazardous Substances Data Bank (HSDB). 2011. “1,4-Dioxane.” http://toxnet.nlm.nih.gov/cgi-bin/ sis/htmlgen?HSDB

[24] Health Canada. Consumer Product Safety. Cosmetic Ingredient Hotlist: List of ingredients that are prohibited for use in cosmetic products. 1,4-Dioxane. Available online: http://www.hc-sc.gc.ca/cps-spc/cosmet-person/hot-list-critique/hotlist-liste-eng.php

[25] European Union: List of substances prohibited in cosmetic products. Ethylene oxide. Available online: http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:32009R1223

[26] FDA: U.S. Food and Drug Administration. 1,4-dioxane a manufacturing byproduct. 2014. Available online: http://www.fda.gov/Cosmetics/ProductsIngredients/PotentialContaminants/ucm101566.htm