Despite the substantial attention paid by the lay
press every year to the safety of DEET, this repellent
has been subjected to more scientific and toxicologic
scrutiny than any other repellent substance. The extensive
accumulated toxicologic data on DEET have
been reviewed elsewhere.
17,35-39
DEET has a remarkable
safety profile after 40 years of use and nearly 8 billion
human applications.
35
Fewer than 50 cases of
serious toxic effects have been documented in the
medical literature since 1960, and three quarters of
them resolved without sequelae.
35,37
Many of these
cases of toxic effects involved long-term, heavy, frequent,
or whole-body application of DEET. No correlation
has been found between the concentration
of DEET used and the risk of toxic effects. As part
of the Reregistration Eligibility Decision on DEET,
released in 1998, the Environmental Protection Agency
reviewed the accumulated data on the toxicity of
DEET and concluded that “normal use of DEET
does not present a health concern to the general U.S.
population.”
40
When applied with common sense,
DEET-based repellents can be expected to provide a
safe as well as a long-lasting repellent effect. Until a
better repellent becomes available, DEET-based repellents remain the gold standard of protection under
circumstances in which it is crucial to be protected
against arthropod bites that might transmit disease.