Division 2.1 Principle

United Kingdom

The method is based on the fact that the cationic dye methylene blue forms blue salts with anionic surfactants (MBAS), which can be extracted with chloroform. To eliminate interference, the extraction is first effected from alkaline solution and the extract is then shaken with acidic methylene blue solution. The absorbency of the separated organic phase is measured photometrically at the wavelength of maximum absorption of 650 nm.

Notes on the whole EU Regulation

Textual amendments

F1: Substituted by Regulation (EC) No 1336/2008 of the European Parliament and of the Council of 16 December 2008 amending Regulation (EC) No 648/2004 in order to adapt it to Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures (Text with EEA relevance).
F2: Deleted by Regulation (EC) No 219/2009 of the European Parliament and of the Council of 11 March 2009 adapting a number of instruments subject to the procedure referred to in Article 251 of the Treaty to Council Decision 1999/468/EC with regard to the regulatory procedure with scrutiny Adaptation to the regulatory procedure with scrutiny — Part Two.

Notes on Annex VIII

Textual amendments

F1: Words in Annex 8 substituted (31.12.2020) by The Detergents (Amendment) (EU Exit) Regulations 2019 (S.I. 2019/672), regs. 1, 29; 2020 c. 1, Sch. 5 para. 1(1)