1. AIM: How is hair analyzed in forensics? Do Now:A single scalp hair approximately 14 inches long was found on a female victim of African descent who lives alone. The hair had a low distribution of phenomelanin in the cortex, a slightly oval cross section, and a medulla that was fragmented. What might the person that police wish to question look like? HW:complete questions on back of hair analysis lab

2. AIM: How is hair analyzed in forensics? Do Now:Compare the layers of a pencil to the layers found in hair. What would the paint represent? The wood? The lead? HW: Textbook Read pages 201-204. Write out and answer each bold faced question on hair identification

3. What are the parts of a hair strand? 1.Root/bulb Embedded in hair follicle 2.Shaft Composed of 3 layers –Cuticle –Cortex –Medulla 3.Tip Where the hair strand ends

4. How can you determine different types of hair by analyzing the medulla?

5. Medulla 3 types of medulla found in human hairs –I.Continuous- most East Asian scalp hairs + pubic hair –II.Fragmented – –III.Absent- Most human scalp hairs other than East Asian Continuous Medulla Solid canal throughout hair Fragmented Medulla Interrupted canals throughout hair Absent Medulla No Medulla Found

6. Root of Hair Provide the tools to produce hair and continue its growth 3 Stages of Growth (different looking roots) –Anagen -initial phase may last up to 6 years, root is flame shaped –Catagen –transition phase (2-3 weeks), root is elongated –Telogen –phase where hair naturally falls out of the skin, root is club-shaped

7. How could Fajardo Aceves Jesus Manuel remove his hair

8. Why is hair analysis so important? We lose and replace about 100 hairs per day. It’s likely that we left a strand of hair in everyplace we traveled to yesterday

9. Why are hairs collected for drug tests? Materials that come into the body can be delivered by blood to hair follicle Material can be deposited in cortex of hair

10. Why are hair follicle drug tests becoming widely used? Drugs and their metabolites can be detected over longer periods of time than blood, urine, or saliva tests Since hair grows about 1cm (½ inch) a month, we can get a timeline of when drug use We can see how often person uses drugs (every week or once in the last 3 months)

11. Tuesday

12. SubstanceUrineHairBlood/Saliva Alcohol6–24 hours up to 2 days12–24 hours Methamphetamine3 to 5 daysup to 90 days 1–3 days MDMA (Ecstasy24 hoursup to 90 days 25 hours Cannabis3 to 7 days, up to >30 days after heavy use and/or in users with high body fat up to 90 days2–3 days in blood, up to 2 weeks in blood of heavy users. Saliva for 2–6 hours Cocaine2 to 5 daysup to 90 days2 to 5 days Cotinine (a break-down product of nicotine) 2 to 4 daysup to 90 days2 to 4 days Heroin3 to 4 daysup to 90 days1– 2 days LSD24 to 72 hoursup to 90 days0 to 3 hours

13. What other materials can be traced in hair? Poisoning by heavy metals (Arsenic, Mercury, lead) Dietary deficiencies (low vitamin and mineral levels)

14. What is a drawback to hair testing? Scalp oils coat the cuticle of the hair and sometimes capture materials from environment Ex: crack smoke in car Can cause “false positives” Scientists must be careful to examine only the cortex of the hair

15. http://www.youtube.com/watch?v= GPrYZ9wwCv4www.youtube.com/watch?v= GPrYZ9wwCv4 http://www.cbsnews.com/video/watch/?id= 7253008nhttp://www.cbsnews.com/video/watch/?id= 7253008n