The best advice I can give is to talk to your care provider/vet and go with what you feel is right.
I'm no doctor of any kind. I research everything I use or recommend and truly believe in it. My medicinal background is experience and study as an Herbalist, Midwife and Vet Tech. But I'm not perfect :)
Even among learned Veterinarians, opinions differ often and sometimes wildly.
Personally, I'm of the opinion that the dust of anything is harmful if inhaled. Diatomaceous Earth is crushed, fossilized diatoms which are abrasive. Even baby powder is harmful if breathed :) I've known plenty of people who use DE on their carpets and I hear it recommended often. I personally wouldn't.
For egg whites, again I differ other opinions but I also differed when the Attorney general told us that eggs were very bad for human health. Until they changed their minds a few years later :) I think the key to anything is moderation. To much of anything is bad and can be dangerous.
I am not a doctor in any way, shape or form.
Please consult your Care Provider before using any herbs or natural medicinals. Anyone can be allergic to anything, if you're unsure it's better not to use it. Double check everything with you Care Provider if you're pregnant or nursing.
Nothing works for everyone and nothing works exactly the same for everyone. Do the research yourself. Don't take any one persons word for anything, no matter how knowledgeable they seem. Doctors with years of experience make mistakes that cost lives. It's your body, (your home, your car, garden, etc etc etc) take responsibility for it.