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Organophosphate pesticides are known for their hazards to human health. Prenatal exposure, for example, has been linked to delayed brain development, reduced IQ, and attention deficits.

As a result, pyrethroids-synthetic chemicals derived from natural chemicals found in chrysanthemums-have risen in popularity over the past decade.  There are currently more than 3,500 commercial products containing this insecticide. This includes items like roach sprays, flea bombs, and dog flea or tick collars and medicated shampoos.

Pyrethroids are well-known to be highly toxic to cats, and the most frequent reason for pyrethroid poisoning in cats is the incorrect and unadvised application of dog flea or tick medication.

You can identify pyrethroids in any given product by reading the label. Compounds that end in “thrin,” such as bifenthrin, permethrin and cypermethrin, are all pyrethroids. Alas, switching to pyrethroids may not have been the wisest move. Animal studies suggest it causes neurological-, immune-, and reproductive damage. And, as usual, the human health effects are still largely unknown, despite its widespread use.

Now, Canadian research suggests pyrethroids may be associated with behavior problems in children.  As reported by Scientific American:

“The findings raise some questions about the safety of the compounds, which have replaced other insecticides with known risks to children’s brain development.

Exposure to pyrethroids, which kill insects by interfering with their nervous systems, is widespread because they are used inside homes and schools, in municipal mosquito control and on farms.”