Scientists have expressed safety concerns about insect repellents that contain Deet after observing the chemical's toxic effects in mammals. Deet has been in use for decades and is found in most of the commonly used repellents to ward off mosquitoes. The study in the open access journal BioMed Central Biology shows deet works in the same way as paralyzing nerve gases used in warfare. However, experts cautioned that the findings in animals could not be translated to humans.
Deet (N,N-diethyl-meta-toluamide) was developed by the US Army in 1946 following its experience of jungle warfare during the second world war, then registered for use by the general public in 1957. Researchers say more investigations are needed to discover any potential neurotoxicity to humans.
In work on rodents at the cellular level, deet blocked an enzyme called acetylcholinesterase, whose job is to control one of the main chemical messengers used by the nervous system.The researchers also found that deet interacts with carbamate insecticides, used in agriculture, increasing their toxicity.
The US Environmental Protection Agency said it would evaluate the study and incorporate it into its future review of DEET planned in 2012.
------------------------------------------------
The active ingredient in many insect repellents, deet, has been found to be toxic to the central nervous system. Researchers say that more investigations are urgently needed to confirm or dismiss any potential neurotoxicity to humans, especially when deet-based repellents are used in combination with other neurotoxic insecticides.
Vincent Corbel from the Institut de Recherche pour le Développement in Montpellier, and Bruno Lapied from the University of Angers, France, led a team of researchers who investigated the mode of action and toxicity of deet (N,N-Diethyl-3-methylbenzamide). Corbel said, "We've found that deet is not simply a behavior-modifying chemical but also inhibits the activity of a key central nervous system enzyme, acetycholinesterase, in both insects and mammals".
In a series of experiments, Corbel and his colleagues found that deet inhibits the acetylcholinesterase enzyme – the same mode of action used by organophosphate and carbamate insecticides. These insecticides are often used in combination with deet, and the researchers also found that deet interacts with carbamate insecticides to increase their toxicity. Corbel concludes, "These findings question the safety of deet, particularly in combination with other chemicals, and they highlight the importance of a multidisciplinary approach to the development of safer insect repellents for use in public health".
No comments:
Post a Comment