The sampling results discussed in this consultation were taken from the available investigations of the property, and are not adjusted for limitations or bias in the sampling programs. The Tables presented in this consultation include maximum and median concentrations in the samples collected. Health discussions are based on the maximum concentrations reported and long-term, frequent exposure scenarios, which are reasonably conservative assumptions.
During the Phase I ESA, the contractors noted a pipe leading onto the property from the east. Bay City Engineering personnel identified this pipe as carrying surface runoff from a nearby residential street. The contractors expressed the opinion that the pipe could carry contamination from a release of chemicals along the street onto the property, however, there is no evidence that any such release and contamination has occurred (2).
Much of the property had been recently mowed at the time of the MDCH visit on October 15, 1997. The wetland areas are heavily overgrown, including fairly large trees. Some of the banks around the pond are fairly steep. Walking across the property is difficult in places, though only the ponds themselves are totally impassible. The property is not fenced, and freely accessible. There is a treehouse near the wetlands, and a narrow footbridge across a pond into the wetlands. MDCH staff noticed some litter scattered around the property. Lawn and garden waste had also been dumped onto the property. Between the MDEQ preliminary reconnaissance on October 2, 1997, and their field work on October 15, a sample-location stake had been uprooted and placed in one of the ponds.During the BFRA of the property in October 1997, the MDEQ collected surface soil samples from 20 locations on the property. As seen in Table 1, samples from 4 locations contained arsenic, and samples from 2 locations contained benzo(a)pyrene in excess of the MDEQ Generic Clean-Up Criteria for Residential Use (3, 4). Only one arsenic concentration exceeded the range of concentrations found in background soils in Michigan (6). The locations with the three highest arsenic concentrations found on the property were scattered in the south part of the property. Samples collected between these locations had lower concentrations of arsenic. The fourth location where the arsenic concentration exceeded the MDEQ Residential Criteria was in the northeast part of the property, on the east side of the main pond on the property. A sample from this location also contained the highest benzo(a)pyrene concentrations in the surface soil samples, and the other location where the benzo(a)pyrene concentration exceeded the Residential Criteria was approximately 100 feet northeast of that one, near the property line. The benzo(a)pyrene concentrations were higher than those typically found in background soils, though the values were within the typical range of concentrations of other polycyclic aromatic hydrocarbons (PAHs)1 found in urban soils (Reference 7, Table 5-3).
During the ESA of the property in April and May 1997, the contractor found no apparent asbestos-containing materials (2). However, in October 1997, the MDEQ found a small pile of Transite panels, containing 40% chrysotile asbestos, in the southern section of the property (3).
During the BFRA of the property in October 1997, the MDEQ collected subsurface soil samples from 9 borings on the property. As seen in Table 2, one sample contained arsenic and another contained polychlorinated biphenyls (PCBs) above the MDEQ Residential Criteria (3,4). The arsenic concentration only slightly exceeded the MDEQ Residential Criteria, and was within the range of concentrations found in background soils in Michigan (6). That sample was collected on the west side of the main pond on the property, and detectable levels of PCBs were only found in a sample from the southwest corner of the pond.
A child subject to pica behavior2 might ingest more arsenic from the surface soil on the property than caused changes in the skin color and texture, including skin cancer, in some people who drank water containing high concentrations of the metal for between 12 and 15 years. Pica children are not likely to be on the property, when it is developed as a park, without supervision. Some people who drank water or wine containing high concentrations of arsenic developed elevated rates of cancer of the skin, lungs, bladder, and liver. The U.S. EPA has classified arsenic as a proven human carcinogen (U.S. EPA Class A). Lifetime incidental ingestion of soil containing the arsenic concentration found on the property might result in a low increased risk of contracting cancer (8).
Adverse health effects from exposure to asbestos primarily arise from exposure to free asbestos fibers in air, in water or on surfaces. There is no information available regarding the presence of free asbestos fibers on the property. Transite panels encapsulate their asbestos content sufficiently to prevent effective exposure. However, the panels are lying on the ground in the open, and are subject to weathering that might release asbestos fibers. Some people who regularly worked with asbestos and thereby breathed air containing elevated concentrations of asbestos fibers developed a lung disease called asbestosis or elevated rates of lung cancer. The U.S. EPA has classified asbestos as a known human carcinogen (U.S. EPA Class A). There is no way to evaluate the public health hazard from the asbestos-containing materials on the property (9).
No one is likely to ingest enough benzo(a)pyrene from the soil on the property to incur any adverse health effects. Some laboratory animals whose food contained benzo(a)pyrene developed elevated rates of cancer of the stomach or skin. Some laboratory animals who had benzo(a)pyrene applied to their skin developed elevated rates of skin cancer. The U.S. EPA has classified benzo(a)pyrene as a probable human carcinogen (U.S. EPA Class B2). Lifetime incidental ingestion of soil containing the benzo(a)pyrene concentration found on the property might result in a low increased risk of contracting cancer. There is not enough information available to evaluate the skin cancer risk from contact with the benzo(a)pyrene in the soil on the property (7).
No one is likely to ingest as much PCBs from the soil on the property as has caused adverse health effects. Some laboratory animals who were fed PCBs developed elevated rates of liver cancer. The U.S. EPA has classified PCBs as probable human carcinogens (U.S. EPA Class B2). No one is likely to ingest enough PCBs from the soil on the property to incur any apparent increased risk of contracting cancer (10).
The asbestos-containing material on the property might pose a public health hazard if it is still on the property when it is used for a park. There are also minor physical hazards from the trash present and the terrain on the property.
Remove the pile of Transite panels and other trash from the property and dispose of them properly during any redevelopment.
Landscape the property to reduce access to the physical hazards from steep slopes.
New environmental data or information concerning the future use of this property may require future health consultations.
If any citizen has additional information or health concerns regarding the Keit Property, please contact the Michigan Department of Community Health, Environmental Epidemiology Division, at 1-800-648-6942.
1 Polycyclic aromatic hydrocarbons found on the Keit Property include acenaphthene, anthracene, benzo(a)anthracene, benzo(a)pyrene, benzp(b)fluoranthene, benzo(g,h,i)perylene, cd)pyrene, 2-methylnaphthalene, naphthalene, phenanthrene, and pyrene.