Storage:
-Body might store some chemicals for short or long periods and then gradually works it out of the system once the exposure to the chemical is reduced or eliminated . As long as these chemicals are remain bound such as in blood proteins, they do not do harm. However sometimes these chemicals are released rapidly causing problems:
-Lead is ordinarily released slowly over many years. However, during pregnancy, mother’s bone releases calcium for the fetus along which lead is also released and carried into the fetus
-Fat soluble chemicals remain stored in fat and can be released rapidly when the body needs to use up fat as in the case of low food availability. DDT is a good example