For those of you who are new to this art of cutting, carving, sculpting eggshells with handheld rotary cutters (or to those who have been cutting away but blissfully unaware): The fine dust generated by the cutting of eggshells may be very harmful to you. IF IT IS NOT GOOD FOR YOUR COMPUTER, IT IS NOT GOOD FOR YOUR LUNGS! (or your eyes, or your kids, or pets, spouses, significant others, etc. etc. etc.)
Always use dust protection to capture and remove the egg dust from your environment. Breathing dust that settles on clothing, hands, etc. may be just as hazardous. A mask/respirator should be designed to stop ultrafine particulates like asbestos or lead (and even these may not be sufficient since no tests have been done re: eggshell dust).
REMEMBER: If you can smell the odor of cutting shells then you are inhaling DUST. The dust itself can cause the natural mucous in our bodies and even the tears of our eyes (which are designed to help the body to remove foreign particles, dust, microbes, etc.) to become thicker and therefore decreases their effectiveness. It makes it more difficult to cough or eliminate congestion from the lungs or to eliminate foreign particles (and microbes) from the eyes.
Eggshell dust can carry into the air (and your lungs, eyes...) whatever bacteria or microbes that have been associated with the egg or shell and may also carry airborne microbes that can therefore enter your lungs or eyes, etc. as you breathe. It is just as dangerous to breathe the dust after it has settled on clothing, furniture, hands, etc. Increased incidence of eye/eyelid infections, chronic sinusitis, lung problems, repeated, persistent or chronic congestion, coughs or colds, aggravation of asthmatic symptoms or emphysema-like symptoms, etc. are only some of the problems reported by eggers around the world. Inspiration for faith and art comes by seeing the extraordinary in the ordinary.