Could the Chemicals in Your Child's Lice Treatment Cause Her to Act Out?

angry girl scratching her head
angry girl scratching her head

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According to new research, exposure to certain chemicals used in pest control may be linked to behavioral difficulties in 6-year-olds. And here's the really scary part: These chemicals (known as pyrethroids) are found in a whole bunch of products parents use on the regular, including mosquito repellents and treatments for head lice.

For the study, a team of French researchers analyzed the urine of 287 women while they were pregnant, and then of their children six years later, to see if there was any link between prenatal and childhood exposures and behavior. They found that a higher level of a certain pyrethroid in the urine of the expectant moms was associated with a heightened risk of their 6-year-olds being anxious and withdrawn. And another pyrethroid found in the children's urine samples was associated with a greater risk of defiant and aggressive behavior.

Before you freak out, please keep in mind that while the results are definitely troubling, the EPA has previously found no significant health risk to adults and children from the proper application of pyrethroid insecticides. Also, this is an observational study—so no firm conclusions can yet be drawn about cause and effect—and the researchers admit that accurately assessing pyrethroid exposures via urine samples is difficult because metabolites are cleared from the body in just a few days.

Nevertheless, it's probably best to steer clear of pyrethroids until more research is done, especially if you're pregnant. For lice treatment, the National Pediculosis Association (the nonprofit group behind the website HeadLice.org) suggests manually removing lice eggs with a nit-removal comb. In fact, professional pesticide-free treatment services are now popping up in many cities to treat clients this way either at home or in special salons. There are also several natural, non-toxic ways to control household insect pests. Use the Pesticide Research Institute's PestSmart tool to find information on more than 18,000 pesticide products and select the least-toxic alternatives.

Hollee Actman Becker is a freelance writer, blogger, and mom of two who writes about parenting and pop culture. Check out her website holleeactmanbecker.com for more, and then follow her on Instagram and Twitter.