Or they can't find their cars, forget where they
are going or get lost in once familiar areas. One VA
study found excess motor vehicle deaths<br>among Gulf
veterans and interpreted this as possible increased risk-
taking behavior (Kang and Bullmann, 1996). What the
veterans tell me is that they get confused, go off the
road, mistake the accelerator for the brake, and have
trouble judging stopping distances when they are exposed
to gasoline, diesel exhaust, or freshly tarred
roads. Researchers at the Robert Wood<br>Johnson Medical
School in New Jersey and at the University of Arizona
have noted similar multi- system symptoms and
intolerances to common chemicals, foods, and drugs among the
veterans (Fiedler et al, 1996; Bell et al, 1998).<br>And a
CDC study found that ill Gulf War veterans reported
more chemical intolerances than healthy veterans
(Fukuda et al, 1998). These studies are<br>confounded by
a phenomenon called "masking," which occurs when
people become intolerant to many different things
(Miller and Prihoda, 1999a). As they go through a day,
symptoms triggered by fragrances, hairspray, vehicle
exhaust, foods and medications pile up so they feel sick
most of the time. No one<br>cause can be isolated
because there's too much background noise, and patients
often underestimate the number of exposures that affect
them. This problem is not altogether new. German
researchers described similar intolerances in chemical
weapons workers after World War II (Spiegelberg, 1961).
Nearly 20 percent of agricultural workers on a
California registry<br>for organophosphate pesticide
poisoning (Tabershaw and Cooper, 1966)<br>reported that
even a "whiff" of pesticide made them sick with
symptoms like those of the Gulf War veterans, as did
dozens of government workers a decade ago, after the EPA
headquarters became a "sick building" following remodeling
(EPA, 1989). Similar outbreaks of chemical intolerances
have been reported in more than a dozen countries
(Ashford et al, 1995). These observations suggest that we
may indeed be dealing with an entirely
new<br>mechanism for disease, one which has been referred to with
the acronym "TILT", or "Toxicant-induced Loss of
Tolerance" (Miller, 1996, 1997, 1999).<br>Any one toxicant
appears capable of initiating this process. TILT involves
two steps, initiation and triggering (Ashford and
Miller, 1998): (1) First, a single acute or multiple
low-level exposures to a pesticide, solvent or<br>other
chemical causes loss of tolerance in a subset of those
exposed; (2)<br><br>Thereafter very low levels of common
substances can trigger symptoms -- not only chemicals, but
various foods, medications, alcoholic beverages and
caffeine. Symptoms involve several organ systems. These
intolerances are the<br>hallmark of TILT, just as fever is the
hallmark symptom of infectious diseases. Over the past
several years, the finger has been pointed at a<br>number
of potential causes for Gulf War Syndrome --
everything from the oil shroud to pesticides, vaccinations,
and pyridostigmine bromide. What set off the Gulf War
Veterans? The answer is "all of the above." Exposure to any
one<br>or any combination of these toxicants may, in fact,
be capable of causing a general breakdown in
tolerance that can result in a plethora of beguiling
symptoms. We do not know exactly how this breakdown in
tolerance occurs.