In an exclusive interview with CosmeticsDesign.com USA, Professor Carlos Aizenman speaks about his team’s findings which may suggest the need for a closer evaluation of purportedly “safe” concentrations of MIT present in cosmetic products.
The preservative, used to prevent growth of bacteria is present in a wide variety of leave-on and rinse-off cosmetics and toiletries in concentrations up to 15 ppm is by general consensus considered safe at concentrations of less than 100 parts per million.
Aizenman’s team carried out a series of experiments and investigated how ten days of exposure at concentrations as low as 1.5 ppm would affect whole, living tadpoles as they develop.
“We found that a very small dose (up to 7 parts per million) of MIT caused deficits in basic brain development and behavior of tadpoles. Since MIT is absorbed through the tadpole's skin, the effective dose is likely smaller”, the professor explained.
“Though our results raise concerns regarding the potential impacts of MIT on overall neurological function, we explicitly question the safety of chronic exposure to low-level MIT on the development of the nervous system”, he added.
Harmful to cosmetic consumers?
Despite his concerns, Professor Aizenman stresses that his team’s data does not address whether MIT is harmful to humans in such low doses. “At the concentrations used, there is no evidence that it is harmful to humans. However, the neurodevelopmental consequences of MIT exposure, particularly in occupational settings, in humans have not been studied.”
The study’s broader message does imply that chemical manufacturers and independent labs might need to carry out more tests for neurodevelopmental effects of even low concentrations of products.
“Coupled with these ineffective guidelines, our findings regarding the detrimental developmental impacts of low-level MIT exposure on the nervous system underline the need for a closer evaluation of purportedly “safe” concentrations of MIT present in commercial and industrial products”, Aizenman concluded.