Biogenic amines
Biogenic amines such as putrescine and cadaverine are among the characteristic chemical compounds produced during the decomposition of organic material. Their particular significance lies not only in their intense odour, but also in their role as markers of decomposition processes. They therefore play an important role in the civil search for missing persons – particularly in the training and deployment of cadaver dogs.
Formation and production Putrescine (1,4-diaminobutane) and cadaverine (1,5-diaminopentane) are naturally produced during the microbial breakdown of amino acids. Putrescine is formed from ornithine, whilst cadaverine is derived from lysine. These processes take place under anaerobic conditions, such as those typically found in decomposing tissue. In this process, bacteria produce enzymes (decarboxylases) that convert the amino acids into the corresponding amines.
For scientific and training purposes, however, these substances are not obtained from actual decomposing material, but are synthesised under controlled conditions. Chemical production takes place under laboratory conditions via defined reaction pathways, ensuring high purity and reproducibility. This allows standardised training conditions to be created without relying on biological decomposition.
Handling and safety Handling biogenic amines requires particular caution. Both substances are not only notable for their extremely unpleasant odour, but can also have health implications. At higher concentrations, they irritate the skin, eyes and respiratory tract. There is also a risk of contamination in the workplace, as the odours linger.
Strict safety guidelines therefore apply: handling takes place in well-ventilated laboratories or under fume cupboards, often with the use of personal protective equipment such as gloves and safety goggles. They are stored in tightly sealed containers, often refrigerated, to ensure stability and minimise evaporation.
For training purposes, the substances are usually heavily diluted or applied to carrier materials. Alternatively, so-called ‘scent kits’ are used, which contain a mixture of various decomposition markers to create a more realistic odour profile.
Use in cadaver search Cadaver detection dogs are trained to recognise the specific odour patterns of human decomposition. Putrescine and cadaverine play a central role here, as they are among the earliest and most consistent decomposition products. However, the odour of decomposition is a complex mixture of hundreds of volatile organic compounds, so training is usually conducted on a broader basis.
In the civilian sector – for example, in the search for missing persons or in disaster scenarios – these substances enable realistic and ethically sound training. Dogs learn to detect even the smallest concentrations and to differentiate between various odour sources. Generalisation is particularly important here: the animals should not only react to a single substance, but to the entire spectrum of relevant decomposition odours.
Ethical and practical aspects The use of synthetic or isolated biogenic amines represents a significant advance, as it reduces the need for real human tissue for training purposes. At the same time, standardisation is improved, which supports the comparability of training methods and quality assurance.
Nevertheless, the challenge remains to fully replicate the complexity of real decomposition processes. Modern approaches therefore combine chemical markers with other training methods, such as the use of tissue samples from medical contexts under strict ethical conditions.
Conclusion Putrescine, cadaverine and related biogenic amines are central components in the understanding and practical application of cadaver detection. Their controlled production and safe handling enable effective and ethically sound training of cadaver detection dogs. At the same time, they illustrate how closely chemistry, biology and applied forensics are interlinked – with the aim of providing clarity and certainty in often difficult situations.