Table 1 Seven major diagnostic features of the MCS by Cullen

1.The disorder is acquired in relation to some documentable environmental exposure(s), insult(s),or ileness(es).

2. Symptoms involves more than one organ system.

3. Symptoms recur and abate in response to predictable stimuli.

4. Symptoms are elicited byexposures to chemicals of diverese structural classes and toxicological modes of action.

5. Symptoms are elicited by exposures that are demonstrable (albeit of low level).

6. Exposures that elicit symptoms must be very low, by which we mean many SDs below average exposures known to cause adverse human responses.

7. No single widely available test of organ system function can explain the symptoms.