Chemical substance made in a laboratory. Other chemical substances commonly encountered in pure form are diamond (carbon), gold, table salt (sodium chloride) and refined sugar (sucrose). However, in practice, no substance is entirely pure, and chemical purity is specified according to the intended use of the chemical. Chemical substances exist as solids, liquids, gases, or plasma, and may change between these phases of matter with changes in temperature or pressure. Chemical substances may be combined or converted to others by means of chemical reactions. Forms of energy, such as light and heat, are not matter, and are thus not "substances" in this
Substance of very high concern must be submitted to the ECHA. Substance of very high concern A substance of very high concern (SVHC) is a chemical substance (or part of a group of chemical substances) for which it has been proposed that the use within the European Union be subject to authorisation under the REACH Regulation. Indeed, listing of a substance as an SVHC by the European Chemicals Agency (ECHA) is the first step in the procedure for restriction of use of a chemical. The first list of SVHCs was published on 28 October 2008 and the list has been updated many times to include