Substances with certain hazardous properties that cause special harm to human health or the environment are considered separately, studied in more depth in accordance with new world trends, and such substances are often restricted or banned for some or all uses. As a result of systematic research, such substances can be detected among previously relatively safe substances, and later - regulated. The purpose of such regulation and imposition of restrictions is to properly control the risks associated with the use of these substances.
One way or another, the criteria for classifying a chemical as especially hazardous and prioritizing it are based on the current hazard classification scheme in a particular country. Methods and ways of including a substance in the lists of especially hazardous vary from country to country, depending on the requirements of relevant regulations, but they are similar and aimed at identifying carcinogenic, mutagenic and highly toxic properties of the substance and the ability of the substance to accumulate in environmental and biological systems. The most developed and modern approach to the identification of a substance as especially hazardous (of very high concern) is presented in the EC Regulation 901907/2006, and it is mostly repeated in similar regulations in other countries.
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