As sense of environment protection increases, scientists come up with many biodegradable alternatives to nonbiodegradable products.
For example, when household detergents were developed and came into wide use, foam began to clog streams and sewage treatment plants. The foam was caused by the presence of a complex phosphate, sodium tripolyphosphate, an ingredient in the detergent that reacted with, and removed dirt from, the surfaces of clothes[clothes?:clothes paper cutter machine]. These complex phosphates, collectively called surfactants for their actions on material surfaces, were not biodegradable, and appeared to be harming plants and fish in streams. Detergent manufacturers responded to the problem by replacing phosphates with enzymes like protease and amylase, which are biodegradable.
