Testing of blood is the technique used to detect drugs.
Blood==> Drugs can be identified in the blood. However, using blood as a sample can create problems. For example, collecting a blood sample, with a hypodermic needle is invasive and painful. There is the possibility of infection from the necessary puncture wound. In addition, blood can be the source of a disease such as AIDS or hepatitis. Blood samples can also be difficult to transport and store (for example, they require refrigeration and the use of special additives or preservatives). Moreover, blood specimens are not very stable and may break down over time and become unusable unless special precautions are taken. Finally, when testing blood, the period of time between drug use and the collection of a sample during which a drug can be identified, is quite short for most drugs.
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