Environmental Health News

What's Working

  • Garden Mosaics projects promote science education while connecting young and old people as they work together in local gardens.
  • Hope Meadows is a planned inter-generational community containing foster and adoptive parents, children, and senior citizens
  • In August 2002, the Los Angeles Unified School District (LAUSD) Board voted to ban soft drinks from all of the district’s schools

#137 - The Polluters' Secret Plan, And How You Can Mess It Up!, 10-Jul-1989

The most common pollutants found in water are organic solvents:
trichloroethylene, ethyl benzene, perchloroethylene, and so on. In the
home, water is exposed to the air by many activities (bathing,
showering, flushing toilets, washing clothes, washing dishes, cooking,
and so forth). During these activities, organic solvents can be
transferred from water to air. Furthermore, many common household
products contain organic solvents (paints, varnish, glues, cleaning
compounds). It is therefore no surprise that organic solvents can be
measured in indoor air, often at levels higher than those found in
outdoor air. In many workplaces, exposure to organic solvents is high
and is more or less constant.

A recent study, published in the AMERICAN JOURNAL OF PSYCHIATRY
(November, 1988), of the effects of organic solvents on the human
nervous system gives such a clear picture of the problem that we will
quote it at length. Because the language in the original article is
laced with medical terms, we have tried to provide some translations:

"Because organic solvents have a special affinity [attraction] for
lipid-rich tissues [fatty tissues], including brain tissue, they have
been implicated in producing a wide range of somatic [physical] and
neuropsychiatric [mental, or nervous system] symptoms.

"It is not uncommon for adults exposed to solvents to report increased
forgetfulness, difficulties concentrating, depressed affect [feelings],
heightened irritability, dizziness, motor incoordination [uncoordinated
movement], and weakness in the extremities [hands, feet, arms and
legs]. While it is generally believed that this reduction in physical
and mental efficiency will clear spontaneously several hours or days
after the individual is removed from the exposure source, many
individuals-particularly those who have had multiple episodes of
'solvent intoxication'--complain that their problems have not
disappeared despite the fact that their last exposure occurred several
months earlier.

"Objective evidence of neuropsychiatric impairment has been provided by
several recent epidemiologic and clinical studies. Using structured
psychiatric interviews and behavioral checklists, investigators have
noted that when compared with control subjects or published norms
[average behavior], solvent-exposed workers report more fatigue,
tension, irritability, mood changes, and difficulty with memory and
concentration. On standardized neuropsychological [nervous system]
tests, solvent-exposed workers have been found to perform more poorly
than control subjects on measures of reaction time, memory, abstract
reasoning, visuospatial ability, manual dexterity, and perceptuomotor

In short, there is abundant evidence that occupational exposure to
solvents can fry your brain and nervous system.

One complaint frequently voiced by individuals exposed to solvents is a
medical condition called parosmia, which is a perceived change in the
sense of smell. Often such people not only report that their sense of
smell is altered, but they also complain that certain substances smell
extremely unpleasant. Such individuals find that certain odors, which
they would usually consider neutral or mildly unpleasant, such as hair
spray, gasoline, or perfumes) are exceedingly disagreeable. For some
unknown reason, such people have developed a great sensitivity
("hypersensitivity") to certain odors, a medical condition known as
cacosmia. This unusual sensitivity to odors is often accompanied by
headaches, dizziness, and feelings of nausea so strong that affected
individuals make a concerted effort to avoid repeated exposures to
those substances thereafter.

Now a formal scientific study of blue collar workers has confirmed that
smell hypersensitivity is associated with poor performance on standard
mental and physical tests. Two groups of blue collar workers, one who
had been exposed to solvents, and one who had not, were matched for
age, level of education, and general intelligence. Each group submitted
to a series of tests for hand-eye coordination, learning and memory,
attention span, and other measures of nervous system function. The
solvent-exposed group performed poorly on many of the tests, compared
to the non-exposed group. Those members of the solvent-exposed group
who reported experiencing nausea after contact with certain odors
performed most poorly on tests of verbal learning and visual memory
("Describe the details of the picture I just showed you."). The authors
of the study say the tests do not PROVE it, but the test results are
consistent with a diagnosis of actual brain damage to the odor-
hypersensitive workers.

A word to the wise: When someone says there's "no immediate risk" from
exposure to solvents in your water supply, or the air inside your home,
they are talking about a cancer risk only. We know of no standards for
low-level exposure to solvents that are designed to protect your brain
or your central nervous system. Do we want to raise a generation of
children drinking and breathing small amounts of cleaning fluid day
after day? We do not.

Get: Christopher Ryan and others, "Cacosmia and Neurobehavioral
Dysfunction Associated With Occupational Exposure to Mixtures of
Organic Solvents." AMERICAN JOURNAL OF PSYCHIATRY, Vol. 145 (November,
1988), pgs. 1442-1445. For a reprint, contact Dr. Ryan at Department of
Psychiatry, Western Psychiatric Institute and Clinic, University of
Pittsburgh School of Medicine, 3811 O'Hara Street, Pittsburgh, PA
15213; phone (412) 648-9641 and ask for Dr. Ryan's office.

--Peter Montague



Life appeared on earth about 600 million years ago, according to fossil
records. New types of plants and animals evolved in response to
changing conditions. Today, somewhere between 5 million and 50 million
different species exist on earth. Biologists from all nations have
recognized the existence of only 1.5 million species, in the sense that
they have been given Latin names. In many cases, even named species
have not been studied in any detail.

The best estimate is that half of all species now living on the planet
will become extinct in the next 50 to 100 years as a result of human
activity, according to Princeton University's Dr. Robert May (now moved
to the faculty at Oxford University in England). [See SCIENCE magazine
Vol. 241 (September 16, 1988), pg. 1448.]

The loss of species affects us all in very practical ways. The planet
earth is an exceedingly complex machine with all its parts interrelated
and interdependent. You can compare it to a TV set (though a TV set is
vastly more simple). Killing a species is like ripping a transistor out
of a TV set, hoping to improve the set's performance.

More than 95% of all pharmaceutical drugs in use today were produced by
nature and discovered by humans--they were not invented by humans. Loss
of species will rob our children of nature's storehouse of biological
inventions. Before our children have even had an opportunity to find
out what benefits might be derived from most species, they'll be
extinct, gone and, with them, whatever benefits they held.

--Peter Montague


Descriptor terms: trichloroethylene; ethyl benzene; perchloroethylene;
health effects; nervous system disorders; risk assessment; studies;