Reading between the corporate disclaimers and regulator hedging, my takeaway from the thorough and impressive investigation into over-the-counter, spot-on pesticide products for pets  by The Center for Public Integrity is: Why risk it? And it’s beginning to look like the Environmental Protection Agency  (EPA) might be asking the same question.
Based on an unprecedented review of 10 years’ worth of adverse-reaction reports filed with the EPA by pesticide manufacturers, The Center reported in December an alarming number of deaths had been linked to topical pesticide products with pyrethrins and pyretroids. These reports include chilling accounts of chemical burns, nerve damage, anorexia and 1,600 deaths over the past five years. On April 16, the EPA “announced that it would intensify its evaluation of these products ‘due to recent increases in the number of reported incidents.’”
I strongly urge anyone currently using over-the-counter, spot-on pesticide treatments to read the report through to the end. (If you’re wondering about the reporters’ angle: The Center for Public Integrity  is a nonprofit, non-partisan organization dedicated to producing investigative journalism on a broad variety issues of public concern. Past stories have included an expose on the use of the Lincoln Bedroom for political contributors in the Clinton administration, publishing secret Patriot II Act draft legislation, and reporting that Halliburton was the largest private contractor in Iraq and Afghanistan.)
Certain details in the story jumped out at me, including the fact that the high concentrations of pyrethroid used in pet products range from between eight to 17 times stronger than the strongest pyrethroid product currently approved for use on humans. Plus, recent findings that pyrethroids in young rats “could result in detrimental effects on neurological function later in life” even when there are no immediate, acute symptoms.
The report also points out that EPA approval is no guarantee of safety. Since 2000, pet products with chlorpyrifos, diazinon and phosmet were successively “approved, defended aggressively by the chemical industry, and then yanked off the market.”