Drug Testing: A Hair-Brained Idea

Aim: How do drugs get out of the blood and into hair follicles? Do Now : When is the last time you think this girl washed her hair? What evidence supports your claim? What happens to hair if it isn’t washed for a long time? Sebaceous Gland : releases sebum Sebum: a fa...

Aim: How do drugs get out of the blood and into hair follicles? Do Now : When is the last time you think this girl washed her hair? What evidence supports your claim? What happens to hair if it isn’t washed for a long time? Sebaceous Gland : releases sebum Sebum: a fatty substance made in and secreted by sebaceous glands attached to hair follicles Sebum is a lipid and is non-polar It provides a layer on your skin to retain moisture Pair/Share: Although maybe unpleasant, why is sebum (a lipid) a good thing to have on the surface of your skin? How do drugs enter the hair follicle? Capillaries are attached at the base of the hair, drugs in the bloodstream are taken up by the follicle Drugs can also enter hair through the sebaceous glands Which form of drug testing do you think is most effective for employers to use? Claim : Evidence : Examples, quotes, textual references that support the claim … Reasoning : An explanation and/or analysis of the evidence Station #1: Urine Testing Urine testing. Urinalysis is currently the only approved drug-testing method for workplaces covered by federal guidelines. It's easy to collect the specimen, which can be screened for many illicit drugs as well as prescription medication, said David Bell, the CEO of USA Mobile Drug Testing, a drug-testing provider in Tampa, Fla. On the other hand, people have figured out how to cheat on the test, Simo said. "Urine as a specimen is very easily manipulated. There are literally hundreds of websites out there that sell adulterants and synthetic urine for people to buy that can subvert a urine drug testing program." But cheating may not be that easy. Bell said that while employers typically don't observe workers while the specimen is collected, increasing the risk of tampering, "a urine screen is difficult to cheat as the temperature, pH and creatinine is checked to ensure specimen integrity. Attempts to dilute a urine specimen will only create a specimen that is inconclusive and requires a retest." Station #2 Saliva Testing Saliva testing. Oral fluid testing can be collected immediately onsite, which makes it more efficient and reduces the amount of time and cost for collection, Bell said. "The test can detect use that has been extremely recent where urine tests require the drugs to have passed through your system to identify." Saliva testing has a lot of appeal, Nieman agreed, "especially for employers who want to do it themselves. Testers can get FDA-approved onsite swab tests, observe the specimen collection — making it hard to subvert — and send it off to the lab for confirmation. However, some states and localities limit or prohibit onsite testing, so employers need to be aware of the laws that apply to them." Because of the small detection window—from a few minutes up to about 48 hours—oral tests are likely catching chronic daily users, Simo said. "These are the people you want to deter and keep off your job site because they represent the most imminent risk." But the limited detection window is also its drawback. "It can only detect drug use that as happened within the past couple of days," Bell said. Station #3 Hair Testing Hair testing. Drug-testing hair is a simple and noninvasive way to detect drug use over a greater length of time, most effective when testing for regular use of drugs such as cocaine, methamphetamines and opiates. These drugs can become undetectable in urine after three to four days. "Hair testing has the highest 'fear factor' as a deterrent," Simo said. "Employers that advertise hair testing deter drug-using applicants that just stay away. It's impossible for regular users to prepare for it." On the other hand, it typically does not do a good job at detecting sporadic usage, he said. And "it doesn't really cover the few days right before the test, because it takes time for hair to grow," Nieman said. Exit Ticket: You recently offered a position to a candidate at one of your retail locations. He had a reasonable amount of head hair at the time we offered the job. After learning that we require hair testing both for new hires, and for random screenings thereafter, he told us that he doesn’t have hair any more, and he probably won’t once he starts working. He insists that he cannot provide a hair sample for testing purposes. What do you do now? Candidate at interview Aim: What properties allow substances to remain in hair? Do Now: What color is your hair? Why? What chemicals contribute to the color of your hair (natural or dyed)? Quiz on Friday! Once drugs such as morphine, cocaine, nicotine or amphetamine get into the hair follicle, they bind to melanin, the pigment that gives hair color. Each of these drugs shares a common chemical property that makes them likely to bind to hair melanin. They are all weak bases . So, they tend to accept a H + when they are in an acidic environment (where there is a high concentration of H + ). Drugs bind to melanin The more melanin you have in your hair the darker it is What does this mean for people with darker hair in terms of drug testing? Everyone took the same amount of codeine (30mg) 3x/day for 5 days Hair was tested at 4, 5, 6,7 weeks What do you notice in these graphs? Evidence Collection Question: Would drug-testing of hair from people with different color hair (blonde vs brown or black) or from people of different races reveal different amounts of drugs, even if they all had taken the same dose? What kinds of dilemmas does this pose in cases of drug-testing in sporting events or in the workplace? Topic Sentence for each source Main Idea Supporting Evidence Questions/Follow-up Summary : What differences are there in hair that can change the amount of substance inside of it? Aim: What properties allow substances to remain in hair? Do Now: Theoretically , if Mrs. Cosentino and Mr. Oritz took the same amount of drugs. Then Mrs. Cosentino bleached her hair and Mr. Ortiz chemically straightened his hair. Who statistically would have more drugs present in their hair? Why? Claim: Dog buried the cat Evidence: Cat’s collar in dirt under dog’s paw Reasoning: Dead things are often buried, dog bribed owner Claim/Evidence/Reasoning Question: Would drug-testing of hair from people with different color hair (blonde vs brown or black) or from people of different races reveal different amounts of drugs, even if they all had taken the same dose? What kinds of dilemmas does this pose in cases of drug-testing in sporting events or in the workplace? Claim: Evidence: Reasoning: Aim: How can redox change your hair texture? Do Now: Write/Pair/Share: Do you know what kind of hair you have? Why are there different types of hair? Keratinocytes : make keratin Keratin: protein that has many sulfur bonds that give hair its strength and structure Polar or non-polar molecule? Write three noticings you have looking at this person’s hair and their follicle 1. 2. 3. Write three noticings you have looking at this person’s hair and their follicle 1. 2. 3. Write three noticings you have looking at this person’s hair and their follicle 1. 2. 3. Write a conclusion about follicle shape and hair texture THE CHEMICAL MAKEUP OF HAIR Hair is predominately made of keratin, which contains sulfur chemical groups. o The more disulfide bonds the curlier the hair Keratin Pair/Share: Work with a partner, using Table R of the reference table, collect three pieces of evidence that could tell us what type of organic functional group keratin belongs to. Write/Pair/Share: Why does a perm does different things to your hair based on your hair type? If keratin is an amino acid, what can we add to it to neutralize it? Acid + Base —> Water + Salt Neutralization Reaction What type of reaction is this? What are the names of the reactants and products? (use table K and L) HCl + NaOH → H 2 O + NaCl Aim: How can we use redox to change our hair texture? Do Now: What type of bonds are broken when someone gets a perm? Redox Reactions - where electrons are lost and gained Oxidation: A chemical reaction where electrons are lost by an atom or ion Reduction: a chemical reaction where electrons are gained by an atom or ion Redox Reaction: oxidation of electrons and reduction occur within the same reaction These reactions are often involved in breaking and forming bonds LEO says GER Review: What type of bonds could be broken in a keratin molecule? Which bonds do you think would have the most impact on the structure of hair? Why? HSCH 2 COO − + NH 4 + ⇌ HSCH 2 COOH + NH 3 Oxidation Numbers • Oxidation Number (state): number assigned to keep track of electrons gained or lost in a redox reaction Pair/Share: Why does N have 8 oxidation states and O only one? Counterintuitive : goes against what you think should happen • Oxidation: defined as the loss of electrons by an atom or an ion • Reduction: defined as the gain of electrons by an atom or an ion • Pair/Share: This seems counterintuitive, why? Identifying Oxidation and Reduction • Atom that shows the increase, oxidation • Atom that shows the decrease, reduction • MnO 2 + 4 HCl → MnCl 2 + Cl 2 + 2H 2 O