Hair Analysis: Applications and Uses in Practice

In recent years, the number of substances that can be detected by chemical hair analysis has increased significantly. Drugs in particular are of interest to forensic scientists – after all, they can have an enormous influence on the situation, for example, in the case of a criminal offense. The informative value of hair analysis is so good that hair serves as evidence in court and is used, for example, for driving aptitude tests after a driver’s license has been revoked due to drug use. Substances that can be detected for several months or longer include opiates, cocaine, cannabis, amphetamines, hallucinogens, “knockout drugs” and doping substances.

In addition, drugs such as antidepressants, alcohol markers and nicotine can also be found. From the level of concentration of the substances and their degradation products, conclusions can be drawn about consumption behavior. This goes so far that, for certain substances, it can be read from a hair, similar to the annual rings on trees, whether and how phases of intake and abstinence alternated.

Hair analysis in environmental medicine

Toxic heavy metals and essential trace elements can be detected in hair. Hair analyses are well suited for checking exposure to arsenic, lead, cadmium, and mercury in a larger population. The method has the advantage that – apart from the possibly psychologically agonizing cutting off of a tuft of hair – there is no painful intervention. Children are particularly well suited to such screening methods, as their hair is usually not yet cosmetically treated. In practice, the main focus is on lead and mercury.

Old water pipes made of lead are still in use in up to 10% of households in Germany (except in southern Germany – which is practically “lead-free”) – if drinking water from the tap is used, this can lead to increased exposure, especially in children, with disorders of the nervous system and blood formation and symptoms such as hyperactivity. Mercury can also lead to signs of illness and developmental disorders, especially in children.

Hair analysis in naturopathy

In alternative medicine, hair analysis occupies a high place. Disturbances in the mineral balance of the human organism are seen as triggers for many diseases, as is an overload of heavy metals. According to naturopaths, the deficiencies are often initially noticeable only subliminally. Hair analyses are therefore recommended when those affected do not feel really ill, but also not really fit. During the examination, more than 60 substances are determined, including iron, chromium, arsenic, copper, nickel, manganese, lead, cadmium and mercury.

The findings include statements about stress and deficiency states, conclusions are drawn about the cause of the disease, and recommendations are made for dietary changes and therapy. The difficulty lies in establishing binding guideline values for the individual substances, the increase or decrease of which causes disease. How far deficiency symptoms are really which and must be balanced therefore or when loads must be eliminated, over it school medical profession and naturopaths are frequently disagreed. Therefore, the room for interpretation is very large.

The therapy recommendations given by the laboratories usually include taking certain trace elements and – to check the success – repeating the analysis after a few months. However, the extent to which expensive treatment based on criteria that are not uniformly defined is useful remains questionable. Moreover, standardization of measurement methods and results in different laboratories is not always given.

Substances detectable in hair and their most common sources of uptake:

  • Lead: contaminated drinking water, plant foods with a large leaf surface (e.g., kale), offal; car exhaust, batteries, paints, pottery
  • Mercury: amalgam fillings, fish, (v.a. shark, halibut, swordfish, sturgeon, tuna, eel, perch, pike, pikeperch), thermometers.
  • Cadmium: food (offal, seafood, wild mushrooms); cigarette smoke, car exhaust; paints, batteries, fertilizers.