How is THC detected?
THC and its degradation products are detected with the help of special drug tests. On the one hand, these can be easy-to-use THC rapid tests – for example THC test strips – which give an indication of the consumption of cannabis. If the measured amount is above the so-called cut-off, the test is considered positive. The cut-off is a threshold above which drug use must be assumed.
On the other hand, sophisticated laboratory methods such as gas chromatography-mass spectrometry are also used for cannabis detection, which can additionally determine the amount and often even the type of consumption.
How does THC breakdown work in the body?
The most common way of ingesting THC is by smoking cannabis in the form of hashish (resin) or marijuana (flower), or cut with tobacco as a so-called joint. In addition, THC is processed in food or beverages. THC is a lipophilic (Greek for fat-loving) substance, i.e. it binds to fat. Since the body converts (metabolizes) THC very quickly via intermediate steps to THC-carboxylic acid, only the metabolites can be detected after a few hours. However, these have a much longer half-life, so THC carboxylic acid can even be found in body fluids up to weeks after the last consumption, depending on the frequency of use.
How long is THC detectable in the blood?
How long is THC detectable in urine?
The urine test for THC carboxylic acid is the most commonly used method, as it allows cannabis to be detected very quickly and easily. In addition, the metabolites can be detected here for up to several weeks if consumption takes place regularly. Thus, even smoking cannabis once can lead to positive detection after 24 to 36 hours. Repeated use leads to a detection period of five to seven days, and chronic abuse can even be detected for several weeks.
How long is THC detectable in hair?
Theoretically, the degradation products of THC are incorporated into the hair matrix during hair growth. Assuming that the growth rate is one centimeter per month, THC use could be detected in twelve centimeters of hair that occurred up to one year ago. However, hair analysis is a highly error-prone procedure, as even a weekly THC intake is often not detected by the test. In contrast, even the use of a hemp shampoo can lead to the retention of active ingredients that result in a positive test result.
What do you have to consider when it comes to the detectability of THC?
Since a THC rapid test only provides positive evidence of consumption, but does not allow any statement about the quantity consumed, traffic controls, for example, can result in severe legal consequences, even though the intoxicating effect has already dissipated.
