Isotope analysis
A recent development in forensic science is the isotopic analysis of hair strands. Hair has a recognisable growth rate of 9-11mm per month or 15 cm per year. Human hair growth is primarily a function of diet, especially drinking water intake. The stable isotopic ratios of drinking water are a function of location, and the geology that the water percolates through. Sr, Sr and oxygen isotope variations are different all over the world. These differences in isotopic ratio are then biologically 'set' in our hair as it grows and it has therefore become possible to identify recent geographic histories by the analysis of hair strands. For example, it could be possible to identify whether a terrorist suspect had recently been to a particular location from hair analysis. This hair analysis is a non-invasive method which is becoming very popular in cases that DNA or other traditional means are bringing no answers.
Ingrown hair
Ingrown hair is a condition where a hair curls back or grows sideways into the skin. The condition is most prevalent among people who have coarse or curly hair. It may or may not be accompanied by an infection of the hair follicle (folliculitis) or "razor bumps" (pseudofolliculitis barbae), which vary in size. While ingrown hair most commonly appears in areas where the skin is shaved or waxed (beard, legs, pubic region), it can appear anywhere. Anything which causes the hair to be broken off unevenly with a sharp tip can cause ingrown hairs. Ingrown hairs are also caused because of lack of natural exfoliation in the skin.