What is MCS?
In theory, MCS is an adverse physical reaction to low levels of many common chemicals. Chemical sensitivity is generally accepted as a reaction by certain individuals to chemicals but debate rages on whether MCS is classifiable as an illness. One of the difficulties in classifying MCS as an illness has been the complex nature of chemicals in the environment and the interaction effects with and within the human body. The length of exposure, the concentration of the chemical(s), and the individual's threshold of resistance are also factors complicating a simple definition. In the relatively few but growing documented cases of severe reactions to chemicals, there seems to be no single stimuli or predictor of reactions. The most severe cases, often called either Environmental Illness or 20th Century Disease, sometimes result in individuals isolating themselves from society, synthetic products, and any type of chemical product.