MDCH Releases Findings Of Pilot Exposure Investigation In Tittabawassee River Flood Plain

Contact: T.J. Bucholz (517) 241-2112


A draft Public Health Consultation released today by the Michigan Department of Community Health (MDCH) has found that dioxin levels in some Tittabawassee River Flood Plain study participants were higher than background estimates, state officials said.

The average total dioxin toxic equivalent (TEQ) blood levels for 20 participants in the study were higher than the average background estimates for people of the same age with no known exposure to dioxins beyond background.

Known exposures would include those that are related to occupation, living close to an industrial source of dioxin, or eating food known to contain high levels of dioxins, said Linda D. Dykema, MDCH toxicologist.

Blood TEQ levels in five of 20 participants were higher than what might be expected in 90 percent of people of the same age with no known exposure to dioxins beyond background. TEQ concentrations in the blood of two of these five were also higher than what might be expected in 95 percent of people of the same age with no known exposure to dioxins beyond background.

While some of the TEQ levels in the participant’s blood samples were on the high end of the range, all fell between the lowest and highest levels for people with no known exposure to dioxins beyond background.

The Consultation provides a report of the results of the Pilot Exposure Investigation conducted in the flood plain of the Tittabawassee River. The MDCH Division of Environmental and Occupational Epidemiology conducted this investigation under a cooperative agreement with the federal Agency for Toxic Substances and Disease Registry (ATSDR).

The purpose of the Pilot Exposure Investigation was to provide information on dioxin levels for a limited number of residents of the Tittabawassee River flood plain. Twenty adults living on property within the flood plain allowed the MDCH to take samples of their blood, soil from their yards, and dust from inside their homes.

Participation in the investigation was limited to people whose yard soil showed dioxin TEQ levels above the state residential cleanup criterion of 90 parts per trillion. The results from analysis of indoor dust samples collected from homes confirmed the presence of dioxins in the indoor environment as well.

Because the number of participants was small, whether other people living in the flood plain may have similar dioxin levels in their blood, soil or dust cannot be known.

The Pilot Exposure Investigation Report, “Dioxin Exposure in Adults Living in the Tittabawassee River Flood Plain” is available on the MDCH web page at, or by calling the MDCH toll free at 1-800-648-6942. The MDCH invites the public to review the Report and offer written comments. Copies of the Report are available for public review at the following locations:

  • The Grace A. Dow Memorial Library, 1710 West St. Andrews, Midland
  • The Midland County Health Department, 220 W. Ellsworth Street Midland
  • The Saginaw County Health Department, 1600 N. Michigan Avenue, Saginaw
  • The Tittabawassee Township Office, 145 South 2nd, Freeland
  • The Zauel (Saginaw Township) Library, 3100 N. Center Road, Saginaw
  • The Thomas Township Library, 8207 Shields Drive, Saginaw
  • The James Township Hall, 6060 Swan Creek Road, Saginaw
  • The Hoyt Library, 505 Janes Avenue, Saginaw
  • The Saginaw Bay District office of the Michigan Department of Environmental Quality, 503 N. Euclid Avenue, Suite 9, Bay City

Information and comments should be addressed to Dr. Linda D. Dykema, Michigan Department of Community Health, Division of Environmental and Occupational Epidemiology, 3423 North Martin Luther King Jr. Blvd., P.O. Box 30195, Lansing, Michigan 48909. You may also call the toll-free telephone number, 1-800-648-6942 (1-800-MI-TOXIC).

Comments on the Public Health Consultations must be received by September 11, 2005. All comments received will be evaluated and considered and responses will be provided in the final version of the consultation.