Detergents are cleaning agents containing synthetic surfactants as the main ingredient. Due to their foam-forming properties, it is important that detergents are present in natural waters. Detergent producing companies have changed from the production of alkyl benzene sulphonate (ABS) to the production of biodegradable linear alkyl benzene sulphonate (LAS) since the years of 1960. With this production change, foaming problem in detergents is prevented. Today, the most widely used detergent surfactant is LAS.

The Ministry of Health issued the following notification in 2005: Communiqué on Test Methods for Biodegradability of Anionic, Nonionic, Ampholytic, Cationic Surfactants in Detergents and Biodegradability of Anionic and Nonionic Surfactants. This disclosure describes the biodegradability rates of anionic, nonionic, cationic and ampholytic active substances contained in detergents and their test methods.

According to this communiqué, it is forbidden to provide detergents containing anionic and nonionic surfactants in the formula with a biodegradability of less than 80 percent.

The rate of biodegradability of anionic surfactants can be determined using at least one of the following methods: OECD method, method used in Germany, method used in France, method used in the UK.

The tests that are performed in laboratories accredited in accordance with TS EN ISO / IEC 17025 standards are as follows:

• TS 5606 Surfactants - Detergents - Determination of acidic hydrolysis resistant anionic active ingredient (trace amounts)

This standard describes a method for determining the amounts of anionic active agents resistant to hydrolysis in acidic medium.

• TS 5607 Surfactants - Detergents - Anionic active substances hydrolysable under primary conditions - Determination of anionic active substance hydrolysable and non-hydrolysable

This standard describes a method for determining the content of anionic active substance that can be hydrolysable and non-hydrolysable in detergents.