Hair strand tests

Urinalysis is typically used as a preliminary test because it is less expensive and more convenient than the other tests. Saliva tests and breathalyzers are commonly used. Blood tests, although less frequently employed because they are generally more expensive and invasive, are more dependable, as are hair strand tests. A preliminary positive test using urinalysis must be confirmed by diagnostic tests completed in an analytical laboratory setting, which can take several days to complete. These diagnostic tests include the analytical instruments of gas chromatography (GG),... 

The usage of this type of product consists of three steps the allergy test, the strand test, and application to the hair on the head. 

Now the consumer is ready to use the product. Mix lOOg of the precursor-coupler base with 75 g of the oxidizer base and spread it through the hair, allowing the reaction to proceed for 10 to 20 min or the time indicated by the strand test before rinsing thoroughly with water. 

There are three basic steps to the usage instructions for semipermanent hair dyes first, the allergy test second, the strand test (both are described under... 

When THC metabolites are in the blood, they go through the blood vessels in the head, and get filtered through the hair. THC metabolites remain in the hair as a permanent record. The hair test costs several hundred dollars ( 150-300) and is rarely given because urinalysis is cheaper (approximately 65) and more accurate. (The hair test equipment and setup goes for over a million). According to Jeff Nightbyrd, hair tests are widely used in the casino industry. They cut 50 strands of hair from the scalp, and send it in... 

Kintz reported a case of amineptine abuse in a 45-year-old man admitted to a dermatology unit with extremely severe acne lesions. As it was not possible to evaluate the degree of severity of the intoxication by blood analysis (decided 10 d after admission), a strand of hair (6 cm) was collected in the vertex region. The concentrations of amineptine in the hair segments were 12.23 and 8.06 ng/mg. After the presentation of the results to the subject, he admitted a daily consumption of 60 tablets of 100 mg amineptine. This observation clearly demonstrates the usefulness of hair testing when classic biological samples (plasma, mine) are not available or without interest. 

Real-World Reading Link DNA testing is becoming more routine in medicine, forensic science, genealogy, and identification of victims in disasters. Modern techniques have made it possible to get a useful DNA sample from surprising sources, such as a strand of hair or dried saliva on a postage stamp. 

Pascal, Kintz. Analytical and Practical Aspects of Drug Testing in Hair. Boca Raton, Fla. GRG Press, 2006. Looks at advances in the use of strands of hair for drug testing in the workplace and in forensic crime laboratories and techniques for detecting specific drugs. 

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