I am one of the allergic individuals who suffer from eczema. Thankfully mine is quite mild, and is generally limited to a few areas of skin: backs of knees, hands/fingers and occasionally feet. What effect does this skin condition have on my fingerprints?
For the past few months the skin some of my fingers has been particularly dry and flaky, with the result that my fingerprints have worn away to nothing. Looking closely at them there are deep cracks or grooves in the skin, and a shiny smoothness where one would normally see loops, whorls and arches.
First, I looked at my fingers in daylight. Various fingers are in different states of dermatitis. I chose four fingers showing different signs of print deterioration. I used a smooth ink-pad and smooth paper to make prints, applying approximately equal force to each finger (a firm press). These were then scanned, cropped and reduced, and saved using identical compression/quality settings for each image.
A representative portion of the full print of each finger is shown below. Image compression has been set high (30% JPEG quality on all images). Both of these are deliberate: I do not want to publish my notional identity for all and sundry (I’m going to have enough trouble getting fingerprinted for a national identity card that I don’t need other people forging my fingerprints and stealing my identity).
This finger has an almost perfect fingerprint.
The horizontal line about two-thirds of the way down is a groove/crack showing that the skin on this finger is getting dry. The dark patch in the upper-right of the image is where the skin is starting to wear away.
The cracks in the skin of this finger produce more noticable features than the ridges and grooves of the pad. When I first saw this scan it reminded me of mycology slides I once saw, depicting fungal growth in animal tissue!
Looking at this finger in the light shows an almost completely smooth surface. The print confirms this: wear-and-tear have eroded the ridges to an almost completely flat surface.