What is multiple chemical sensitivity (MCS)?

MCS (multiple chemical sensitivity) is a term used to describe a variety of symptoms that stem from alterations in a person's indoor environment, primarily at work, but sometimes at home. So-called "sick building syndrome" may be caused by chemicals in modern building materials, or it may be a function of ventilation problems caused by new construction methods and energy-saving techniques. Unless new air is exchanged for old air at a certain rate, allergens, toxins, or chemical residue can become concentrated at levels high enough to provoke a reaction. Just as problematic is the process of renovation, when molds, mouse droppings, dust, or chemicals that have been undisturbed may be stirred up and circulate in the building.

Multiple chemical sensitivity (MCS) is a term used to describe the adverse responses to low levels of chemicals present in our everyday environment in hypersensitive individuals. These reactions are not typical in the majority of the population who are also exposed to the same toxicants and seem to tolerate them.

Although first explained in the 1950s, as the amount of chemicals introduced in the environment exploded, it is still not well understood by mainstream medicine. Although some physicians continue to dismiss the disease as psychosomatic, or an emotional disturbance, the US Consumer Product Safety commission and other organizations are advocating that it is a physiological disease that should be treated as such. MCS has been linked to various disorders, such as irritable bowel syndrome.

The process of MCS begins with an initiation reaction induced by a chemical creating intolerance to that chemical. This response then triggers further reactionary patterns to more and more chemicals. Symptoms are varied and can range from allergic responses such as irritation to mucus membranes, breathing difficulties, skin irritation to mood imbalances, muscle and joint pain, and fatigue.

Relatively new and advanced functional tests are showing that some people have a reduced ability to detoxify chemicals. This is due to genetic differences in their liver enzymes which are responsible for detoxifying and ridding the body of these chemicals. Those with these single nucleotide polymorphisms, or SNPs, can use nutritional interventions to boost their bodies detoxifying power and create less severe responses to toxicants. 

Multiple chemical sensitivity (MCS) is defined as "a chronic recurrent condition characterized by reduced tolerance to various environmental agents or to a class of chemical substances."

Researchers from the International Center for Toxicology and Medicine point out that when it comes to people suffering from MCS, there are two leading points of view.

The first sees MCS as resulting from interactions between chemicals and the body.

The second argues that MCS "results from a primary emotional response to perceived chemical exposures."

According to this view, it's not the chemicals that cause MCS, but it is psychological in origin. They are saying it could all be just in your head.

But I believe this view is outdated, based on emerging evidence of the physical impact on the body from toxic exposures. Recent research done in Italy found physical changes that indicated reduced detoxification ability for the people with MCS that were examined.