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Environmental Epidemiology
I had the privilege of doing research into the health effects of pesticides,
air pollution and arsenic water pollution. In 1971, the Utah State Division
of Environmental Health hired me to take charge of a research contract they
had with the U.S. Environmental Protection Agency (EPA). It was called the
Utah Community Pesticide Study. Soon thereafter, EPA asked me to be the project director of the
Utah Community Health and Environmental Surveillance Study (a CHESS study).
Later we received a grant from EPA to study health effects of naturally
occurring arsenic in drinking water in a desert community of west central
Utah. Years after I left my employment as the Environmental Epidemiologist
for Utah's Health Department, EPA contacted me to do follow up arsenic
epidemiology research.
Pesticide Study: Utah was one of 13 states to have a
"community pesticide study" funded by the EPA. We selected men with heavy
exposure to pesticides and a matching group of unexposed men. We gave them
physical examinations, which included laboratory evaluations of various
measures of health status, and pesticide body burden measurements. We
coded physical examination data onto EPA data sheets and mailed them to EPA
for statistical analysis. We were disappointed that EPA could not seem to
handle the voluminous data supplied by all the participating state projects.
No EPA report was ever made of those data, although some of the states tried
to salvage data into some reports. We in Utah prepared some reports on the
Utah data. Generally we could find no evidence of significant health effects
from occupational exposure to pesticides, although health effects from
smoking and alcohol consumption seemed to show up in the data. We also investigated pesticide poisoning
incidents. Generally we found that pesticide poisoning incidents were all
related to failure to use the pesticides according to the instructions on
the pesticide label. Air Pollution Study: Utah was one of 3 or 4 states to have a
contract to study air pollution as part of the EPA CHESS studies. In Utah,
we focused on sulfur dioxide pollution from a point source (the Kennecott
copper smelter in Magna, Utah). We selected four study communities, which
had increasing distances from the smelter: Magna, Kearns, Salt Lake City,
and Ogden. The state health department and EPA did not share the same
perspective of the risk of sulfur dioxide air pollution. The state had the
advantage of years of pollution monitoring and a general understanding of
the health histories of their exposed communities. EPA came with an
institutional bias that exposure to environmental sulfur dioxide pollution
was causing health effects, which could be detected by epidemiological
measurements. EPA jealously guarded the data that we collected for them,
none-the-less we (the State Health Department) extracted the data
electronically before we sent it to EPA. EPA did their statistical
evaluations of the data, prepared official reports, and published their
findings. We did our own statistical assessments of the health effects data.
Generally we found that health measurements did not differ significantly
between the communities with differing levels of sulfur dioxide air
pollution levels. A slight effect could be detected from occupational
exposure to sulfur dioxide, however these occupational effects were
significantly less that the effects detected from cigarette smoking.
None-the-less, public perception of air pollution discomfort was voiced at
times when inversions made the air appear polluted. I learned that these
subjective opinions have significant influence on public policy, despite
contrary indications of objective assessments of health measurement data.
Arsenic in Drinking Water Study: When the rural desert community of Hinckley, Millard County,
Utah drilled its community drinking water well in 1976, the first water
sample that they submitted to the Utah State Bureau of Environmental Health
showed high levels of Arsenic. Additional samples confirmed the presence of
arsenic in the water at nearly 200 parts per billion, almost 4 times the
amount allowed by the drinking water standard at that time (50 parts per
billion). It was known that private drinking water wells in the area
contained similar levels of arsenic, but no health consequences had been
reported. We applied for and received an EPA grant to study the health of
people who lived in that arsenic exposed area. We gathered more drinking
water samples from the area, collected hair and urine samples, and gave
physical examinations to residents. Physical exams included dermatological
exams and nerve conduction velocity tests. Arsenic levels in hair and
urine correlated well with arsenic exposure levels. Neither the
dermatological exams nor the nerve conduction velocity tests showed
correlations with arsenic exposure from drinking water. If there was an
arsenic health effect, it was not obvious. Critics of the study said we did
not have enough people in the study to detect the effects. We started
another approach to the study, by gathering historical records of persons
who had lived in the community, with the idea of comparing death
certificates of exposed and control persons. Exposed persons were selected
from highly exposed communities (Hinckley, Deseret and Oasis) while the
control persons were drawn from a larger, near by town (Delta), which had well-water arsenic below the arsenic standard. This
portion of the study was not finished, due to a lack of funding.
Years later, EPA had renewed need for more arsenic in drinking water health
effects data. I no longer worked for the Utah Health Department, but they contacted me in Idaho to request a follow up arsenic
study in the same area of Millard County, Utah. I had microfiche copies of
the historical records extracted in the first study and converted those
records into an electronic database. Then EPA decided to expand the number
of people in the cohort by extracting more historical records. My team of
assistants worked in ........
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