Emerging indoor pollutants.

There is an increasing use of so-called emerging substances or substances of emerging concern. These terms describe, inter alia, the replacement of commonly used chemicals in formulations by supposedly less harmful chemicals. A well-known example is the shift from DEHP to higher molecular weight phthalates and later the shift from phthalates to DINCH, adipates, terephthalates, etc. Similar trends can be observed in the case of solvents and flame retardants. Over the years, new compound groups such as perfluorocarbons, UV-filters, synthetic musks, parabens, siloxanes, neonicotinoids and drug residues also appeared on the scene. Today, however, the term "emerging substances" has to be defined much more broadly as regards the indoor environment. As a result of the extensive measures for energy-related renovation, contaminated waste products such as asbestos, PCBs, PAHs and PCNs are once again forming the focus of attention as re-emerging chemicals. Many relevant compounds, in particular reaction products, were unknown until recently due to the fact, that they can only now be detected using highly sensitive methods. Furthermore, already known chemicals attract scientific and public interest through reclassification or through the derivation of indoor guideline and reference values. The classical way of monitoring emerging compounds is air and dust analysis and therefore, the spectrum of analytical techniques needs to be continuously broadened. However, there is also a demand for human biomarkers, preferably in urine. A further important aspect is the post-hoc analysis of house dust and urine samples, which are stored in environmental specimen banks. The identification and temporal tracking of emerging chemicals is thereby enabled. It is strongly recommended to take advantage of the possibilities resulting from the combination of classical interior analytics and human biomonitoring to promptly detect emerging pollutants and chemicals of concern.