(16)To ensure a high degree of protection of public interest, and to guarantee fair competition on the internal market, economic operators should be responsible for the compliance of detergents and surfactants with this Regulation in relation to their respective roles in the supply chain. Whenever appropriate, manufacturers and importers should carry out sample testing of the detergents and surfactants that they have made available on the market, in order to protect the health and safety of consumers and the environment.