Multiple Chemical Sensitivity (MCS) is also known as Environmental Sensitivities (ES) or Intolerances. It is an acquired environment linked condition and is sometimes associated with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Fibromyalgia.
The 1999 consensus definition on MCS (in the Archives of Environmental Health – May/June 1999 54(3)) lists the following characteristics of the illness:
- The symptoms are reproducible with (repeated chemical) exposure
- The condition is chronic
- Low levels of exposure (lower than previously or commonly tolerated) result in manifestations of the syndrome
- The symptoms improve or resolve when the incitants are removed
- Responses occur to multiple chemically-unrelated substances
- symptoms involve multiple organ systems
Additionally, in another report “Multiple Chemical Sensitivity” Discrimant Validity of Case Definitions ((in the Archives of Environmental Health–2001:56(5)406-412), it includes:
- Having a stronger sense of smell than others
- Difficulty concentrating
- Feeling dull or groggy
- Feeling spacey
Symptoms can also include headaches, problems with balance and coordination, nervousness, irritability and depressed mood, burning and irritated eyes, stuffy or runny nose, cough, fast or irregular heart beat, nausea, diarrhea or constipation, frequent or urgent urination, achy muscles and joints, and rashes.