Jeff, I'm curious....are your concerns based on feeding a dog DE or spreading it on the ground outside, which I've done with some success (although I have not found it effective on ants, which is curious).
I've never fed it...I have also read the warnings on the bag about breathing it in and wondered....but I'm interested in your thoughts on outdoor use.
That's a
great question! No, I wasn't considering feeding it because I was
assuming that spreading it around various areas was the way it was used (remember, I didn't know
anything about it until recently). Oddly enough, it would seem (to me) that
feeding would be
less of a potential long term problem for the dog than
aspirating the particles. My
guess would be that particles consumed orally would be more easily (and thoroughly) eliminated than the particles trapped in the lungs. I'll have to keep mulling this one over.
What I was
really thinking about was something that I remembered being said in an earlier thread. The conversation centered on DE being sprinkled in areas of the
interior of a house that had flea issues. Even
after vacuuming and cleanup,
I would be worried that residual quantities would remain such that I would be continually worried about the long termed effect on my companion.
Outside, I would have
fewer concerns (not
no concerns, just
fewer) because various environmental issues (dew, rain, temp changes) would seem to make DE adhere to outside surfaces. As such, Rover (Spot or Brutus) would be
less likely to
inhale the particles and
more likely to ingest particles while eating (grass - poop or the occasional low flying moth) from the ground. Like I said, I
think I am less worried about ingestion than inhalation. I
might possibly be moved to treat exterior areas because I could more easily isolate my pup from those areas.
Bear in mind, I
do not paint myself as a expert on DE and this type of thing. What happens occasionally is that something that comes up
here, links up with knowledge from my formal life and I find myself going

. It a former life occupational hazard.