Chlorinated solvents were the choice solvent till thet were proven hazardous to human health and environment. Some chlorinated solvents are suspected to cause cancer (Carcinogenic ) over prolonged exposure . Being hazardous to health their usage has come under intense investigation from pollution control and health authorities. This has lead to a shift to alternative cleaning technology based on aqueous solvents.
Aqueous cleaners are environmentally benign, technically feasible alternative to solvent cleaning. The medium used for cleaning is predominantly water compounded with alkali, surfactants, water conditioners, corrosion inhibitors, foam stabilizers etc.

Aqueous Cleaning systems in many cases have replaced solvents without sacrificing cleaning performance. However due to the nature of the solvent used, successful implementation of aqueous systems require a careful design effort necessitated due to the multistage operations involved like 1) Cleaning with aqueous solution 2)Removal of contaminated solution with water wash and 3) Removal of water.

While solvent based cleaning, primarily rely on the chemical property of the solvent . aqueous cleaning systems rely on the mechanical properties like high pressure spray , ultrasonic agitation, dunking, etc. apart from chemical properties of the aqueous medium.