I personally would not use permethrin around my birds, but that is just my preference. Just because something is labeled as "safe" does not mean it is. Look at all of the dogs who have had holes burned in their skin from topical flea treatments that are supposed to be "safe". It is all a matter of personal preference. If someone has used something for years with no problems great for them, but anyone trying a new product, chemical, etc should be fully informed and do their research before exposing their animals to it. It is all a matter of choice and there's nothing wrong with considering pros and cons and hearing different opinions of a certain remedy. Not everyone chooses to do things the same exact way esp when it comes to poultry.