In 1999 the National Toxicology Program (NTP) completed
a study that found an association between cancer in laboratory
animals and the application of diethanolamine (DEA) and
certain DEA-related ingredients to their skin (Source:
Study #TR-478, Toxicology and Carcinogenesis Studies of
Diethanolamine (CAS No. 111-42-2) in F344/N Rats and B6C3F1
Mice (Dermal Studies), July 1999, http://ntp-server.niehs.nih.gov/).
For the DEA-related ingredients, the NTP study suggested
that the carcinogenic response is linked to possible residual
levels of DEA. However, the NTP study did not establish
a link between DEA and the risk of cancer in humans.
This study "found that repeated skin application
to mouse skin of the cosmetic ingredient diethanolamine
(DEA), or its fatty acid derivative cocamide-DEA, induced
liver and kidney cancer." Besides this "clear
evidence of carcinogenicity [only to mouse skin in high
concentrations]," the NTP also emphasized that DEA
is readily absorbed through the skin and accumulates in
organs, such as the brain, where it induces chronic toxic
effects. The report went on to explain that high concentrations
of DEA-based detergents are commonly used in a wide range
of cosmetics and toiletries, including shampoos, hair
dyes, hair conditioners, lotions, creams, and bubble baths,
plus liquid dishwashing and laundry soaps. "Lifelong
use of these products thus clearly poses major avoidable
cancer risks to the great majority of U.S. consumers,
particularly infants and young children," the report
stated.
It is important to note that this conclusion was a stretch.
Taking results from high concentrations used on mice and
extending them to long-term topical use by humans is not
exactly scientific.
According to the FDA (Source: Office of Cosmetics and
Colors Fact Sheet, December 9, 1999), "Although DEA
itself is used in very few cosmetics, DEA-related ingredients
(e.g., oleamide DEA, lauramide DEA, cocamide DEA) are
widely used in a variety of cosmetic products. These ingredients
function as emulsifiers or foaming agents and are generally
used at levels of 1% to 5%. The FDA takes these NTP findings
very seriously and is in the process of carefully evaluating
the studies and test data to determine the real risk,
if any, to consumers. The Agency believes that at the
present time there is no reason for consumers to be alarmed
based on the usage of these ingredients in cosmetics.
Consumers wishing to avoid cosmetics containing DEA or
its conjugates may do so by reviewing the ingredient statement
required to appear on the outer container label of cosmetics
offered for retail sale to consumers.
"If FDA's evaluation of the NTP data indicates that
a health hazard exists, FDA will advise the industry and
the public and will consider its legal options under the
authority of the Food, Drug and Cosmetic Act in protecting
the health and welfare of consumers."
I can see why some people may want to avoid DEA in cosmetics,
and it is easy enough to do so, but given the specific
research data, the entire issue of risk seems rather alarmist.
In essence, there is as yet no real evidence demonstrating
that people using cosmetics with DEA are anymore prone
to cancers than those not using them.