Direct medical implications include potential risks to human health from the use of biometrics as well as public concerns related to possible hazards. Indirect implications relate to the ethical risk of biometric data being used to reveal private medical information. The former are more a matter of public perception while the latter are more difficult to deal with. Developing this further:
Interaction with a biometric sensor holds two potential health risks. If the system uses a contact sensor there is a risk (real or perceived) of the sensor being contaminated. The real risk may be minimal, especially when compared to similar everyday actions (touching doorknobs, railings) but the perceived risk may have a negative impact on public acceptance. Regular cleaning (e.g. through periodic irradiation with UV light) can minimise concerns and improve sensor performance. The second risk relates to technologies that use radiation to assist acquisition (e.g. retinal scanning which use infrared light). There is a fear that this radiation could be damaging to the eyes. Retinal scanning could cause thermal injury on the back of the eye, but it is a biometric technique that is not currently in use. Data from iris recognition equipment manufacturers show no evidence that iris systems could pose a risk. It would be reasonable however to validate this claim in independent laboratories.
These are more controversial as they refer to fears about the possibility of biometric data revealing sensitive health information, leading to ethical concerns. Iridologists allege that the iris exposes potential health problems, but these claims are scientifically unfounded and thus the only risk may be one of public fear. Retinal scanning could have serious implications as it may enable detection of a subject’s vascular dysfunction. There are also concerns that in the future, face recognition may be used to detect expressions and thus emotional conditions. The ethical debate gets extremely heated when the use of DNA is considered, although the regions of DNA necessary for identification are ‘non-coding’.