Health Risk Assessment
Human health risk assessments form a primary component in the evaluation of risks posed by environmental contamination. Dr. Milton Clark has developed over 100 health risk assessments for hazardous waste sites, situations involving human exposure to pesticides, contaminated soils and sediments, and toxic chemicals in foods. We work with clients to ensure that work products meet federal and state risk assessment requirements and regulatory criteria such as those specified by U.S. EPA.
For more information:
Health Risk Assessment Projects:
Dioxin Contamination: Midland Michigan and Tittabawassee River
In the early 1980s, dioxin contamination was found at unacceptable levels in soils, sediments, and sport fish in the Midland, Michigan area and the Tittabawassee River. The contamination was due to the manufacture and improper disposal of Agent Orange and related chemicals by Dow Chemical. Dr. Clark developed one of the first multimedia risk assessments documenting elevated human health risks from exposure to dioxin. Regional Administrator Valdas Adamkus and Dr. Clark testified before Congress on the health risks of dioxin and suppression of scientific findings by the Reagan Administration. This dioxin issue received national attention and led to studies of dioxin sources throughout the country and new regulations on dioxin emissions from existing industrial plants and incinerators.
For more information:
Hawaii Pesticide Concerns: GMO Pesticide Use on Kauai
Major GMO agricultural companies have operations in the Hawaii Islands to produce GMO corn for seeds. On the island of Kauai extensive pesticide use by the companies was creating public concerns. Per the request of the Hawaii Department of Public Health, Dr. Clark was asked to serve as an outside expert to advise a state appointed task force charged with evaluation of pesticide issues and to make recommendations. To determine if health risks existed or not, Dr. Clark developed key recommendations to sample residential soils, air, and surface waters. A human pesticide exposure study was also recommended. Dr. Clark also testified before the Hawaii State Legislature on the need to create pesticide buffer zones and phase out chlorpryifos, a pesticide that was to be banned by EPA. Hawaii became the first state to ban chlorpryifos in 2017.
For more information:
Contaminated Sediments: Waukegan Harbor, Illinois
At this Superfund site over one million pounds of polychlorinated biphenyls (PCBs) were discharged into Waukegan Harbor and Lake Michigan by Outboard Marine Corporation. PCB levels in sediments were over 10,000 parts per million and fish were found to have some of the highest PCB levels ever observed. While working for U.S. EPA, Dr. Milton Clark performed a multi-media risk assessment to assess current human health risks as well as risks during and following remedial actions. This risk assessment and risk management analysis led to an effective harbor cleanup at reasonable costs. Following cleanup, PCB levels in fish were dramatically lowered reducing public health risks.
Contaminated Soils: Bloomington, Indiana
Industrial manufacture and disposal of PCB transformer oils by Westinghouse Corporation in several area landfills resulted in contamination of soils, groundwater, and surface waters. For this complex Superfund site, human health risk assessments were developed to establish appropriate cleanup levels. To address public health concerns, risk communication presentations were made to the public prior to and during cleanup operations. Remedial actions were undertaken in a cost-effective manner to remove the highest PCB contaminated materials, cap remaining soils in landfills, and install water treatment.
Contaminated Fish and Health Risks
Dr. Milton Clark has pioneered risk assessment techniques for consumption of contaminated fish from Superfund and RCRA sites in the Great Lakes including Manistique Harbor, Michigan; Fox River, Wisconsin; the Kalamazoo River, Michigan; and Tittabawassee River, Michigan. These risk assessments have supported Superfund based remedial investigations (RI), feasibility studies (FS) as well as EPA record of decisions (ROD). Defensible risk assessments for fish consumption require careful balancing of chemical exposures and fish ingestion rates. It is important not to overstate chemical exposure risks, but a the same time ensure that sensitive populations, such as certain ethic groups, women of child bearing age and children, and the developing fetus are protected.