Subject: Health Studies in Midland Michigan
Date: December 5, 1985
December 5, 1985
Health Studies in Midland, Michigan
From J. Milton Clark, Ph.D
Chairman Health Effects Forum
To: George A. Jones, Chief
Superfund Implementation Group
Centers for Disease Control's (CDC's) comments of September 10, 1985
regarding epidemiological and monitoring studies in Midland, are
appreciated. While CDC is of the opinion that such studies are not necessary
or would be difficult to implement, we believe the basis for reaching these
conclusions has not been sufficiently developed.
Exposure to tainted soils in Midland IS BUT ONE POTENTIAL ROUTE OF EXPOSURE
TO PCDDS AND PCDFS. Soil levels of PCDDs and PCDFs in Midland are related to
the distance and direction from the Dow facility.
AIR RELEASES from the facility are believed to be responsible for the PCDDs
and PCDFs observed in soils.
EXPOSURE TO AMBIENT AIR CONTAINING PCDDS AND PCDFS, AND POSSIBLY OTHER TOXIC
CHEMICALS IS CONTINUING TO OCCUR IN MIDLAND.
For instance, the Michigan Department of Natural Resources calculated a 10-4
lifetime cancer risk based on 1978 emissions from only one possible
PCDD/PCDF source at the Dow facility.
Ambient air in Midland currently contains 2,3,7,8-TCDD yielding risks in the
Before any conclusions can be reached regarding the merit of epidemiological
or monitoring studies, current and historical air levels of toxic chemicals
and associated risks would need to be estimated to assess if exposure could
cause adverse health impacts. If risks appeared excessive, then the next
step would be to evaluate a small population of Midland residents located at
distances from the Dow facility where maximum air exposure would be
Regarding dioxin body burdens, it makes no sense not to collect some
measurements on individuals proximal to the Dow facility of consumers of
Tittabawassee River fish to include in a national biomonitoring data base,
considering the potential magnitude of exposure to PCDDs and PCDFs.
We question the ethics of not including some Midland residents considering
that Midland has A HIGHLY SIGNIFICANT SOFT TISSUE CANCER RATE AND AN
HISTORICALLY ELEVATED BIRTH DEFECT RATES WHICH COULD BE RELATED TO PCDDS AND
PCDFS. (See Region V's October 11, 1985 risk assessment of Midland,
We are concerned that the CDC evaluation of the merit of health studies in
Midland is too opinionated and without sufficient documentation to support
the conclusions. While such conclusions may ultimately be supported, a more
thorough and careful analysis is required. For these reasons we shall
continue to explore the merit of health evaluations in Midland using
expertise at the University level. We truly regret the need to pursue this
Source: Diane Hebert