A definition by Cullen is stated as "... an acquired disorder characterized by recurrent symptoms, referable to multiple organ systems, occurring in response to demonstrable exposure to many chemically unrelated compounds at doses far below those established in the general population to cause harmful effects. No single widely accepted test of physiologic function can be shown to correlate with symptoms." (Cullen MR. The worker with multiple chemical hypersensitivities: An overview. Occup Med 1987;2: 655-661)
It is critical that patients with symptoms make sure that they do not have a medical illness that might be amenable to therapy. Symptoms of weakness may be due to a neuropathy, anemia, hypo- or hyper-thyroidism. Headaches and nausea can be due to central nervous system illness or diabetes. Presentation of patients who describe themselves as multiple chemical sensitivity patients condemns them to becoming a nuisance to the medical community from whom they need so much to be assisted by. This is a major problem.
Of great concern is that the legal community has outstripped the medical community in evaluating and dealing with this syndrome. Legal decisions based on other than scientifically documented illness is a sorry reflection on our society and our abilities in the medical community to offer compassion to all comers. I say this because patients tend to go to lawyers for assistance when the physicians do not live up to their expectations.
Regardless of the emotional impact on all of us who deal with MCS or for those patients who suffer from MCS, it is a reality. Of import, is that:
- Medical illness of some other etiology be ruled out before this diagnosis is entertained.
- Assistance be offered through proven techniques and the physician community be informed of scientifically proven therapeutic measures that do exist and where they are available.
- The public be made aware of potential misuse of science by those who wish to benefit financially from the misfortune of the patient with MCS.
Health Based Exposure Limits
The Health Based Exposure Limits are typically levels of exposure too low to measure with current instrumentation. Some may ask, "Why publish levels which are too low to measure, in many cases?" They are included to show the large gap between existing regulations and levels which would more likely provide health protection. They show that there is a scientific basis for the industrial hygiene principle of lowering exposures as much as technologically possible. They also are a compilation of levels based on existing data which communities and workers can use to estimate the possible risks of exposures, particularly if actual exposure levels can be measured or modeled.
A major reason for this booklet has been the disclosure that many older OEL's are tainted by corporate influence and based on shoddy scientific review. The OEL's in the US and other countries, since 1946, have been substantially based on the work of a private organization (called the American Conference of Governmental Industrial Hygienists or ACGIH). This group has had a committee of volunteers that recommended workplace exposure limits for hundreds of substances. Their limits are called Threshold Limit Values or TLV's.
In reality, the ACGIH does not represent a consensus of governmental industrial hygiene opininions. The minutes of the TLV committee show that, starting in 1970, employees of Dow Chemical, DuPont, and other companies have played central roles as committee members in developing TLV's for over 120 chemicals. This company role was not balanced by representatives of workers' interests, such as union representatives. Moreover, the stated basis for the TLV's of over 100 substances relies heavily on unpublished communications from corporations. No trace of most of these communications can be found today (Castleman 1988, Ziem 1989). The TLV committee had no conflict of interest rules to prevent corporate employees and consultants on the committee from, in effect, prescribing allowable poisoning limits for exposure to chemicals used or produced by corporations hiring them. In 1989, weak conflict of interest rules were first adopted in response to public criticism and legal concerns.
Though the TLV booklet preface says the TLV's are adequate to protect "nearly all workers", close examination shows that to be untrue. The published reports of human data cited as the basis for the TLV's often reflect harmful effects at and below the TLV levels (Roach 1990). The literature used for the TLV's was sometimes misrepresented as showing no health problems when significant problems were present (Roach 1990). Current medical reports regularly show that work-related illness and death occur in workers exposed to toxic substances at levels lower than the TLV's (Ziem 1989).
