Fingerprints could give clues about the lifestyle of a person, and that may help forensic investigations.
"Researchers in the UK are uncovering the ways fingerprints are changed by age, smoking, drug use and even some personal grooming products.
There are a lot of lipids in fingerprints and there are a lot of possibilities for that.
Drug users typically excrete the metabolised products of the chemical they use. For instance, smokers are known to secrete cotinine, a chemical produced when the human body breaks down nicotine."
Fingerprint-based systems are likely to be extensively used in the future for authentication. Can you imagine a Google site where you can logon with your fingerprint? Google will know not just who you are, what you've searched, what do you like, but also what's your medical condition, if you smoke or take drugs. Google could personalize the results and promote the sites that offer medical advice relevant to your condition.
Source: BBC News.
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