The Michigan Department of Community Health released its public health assessment of the waters and fish affected by the 2010 Enbridge oil spill.
You can read their report here.
They conclude the spill is "not harmful to health":
MDCH has concluded that no long-term harm to people’s health is expected from contact with chemicals in the surface water during recreational activities, such as wading, swimming, or canoeing. However, contact with oil sheen and globules in the river may cause temporary effects, such as skin irritation.
Fish from the Kalamazoo River and Morrow Lake were tested for oil-related chemicals, as well as chemicals that were previously found in fish there. Fish from areas impacted by the oil spill, including Ceresco Impoundment and Morrow Lake, had similar levels of oil-related chemicals as fish caught in Marshall Pond (upstream of the spill). All oil-related chemical levels were very low. Mercury and polychlorinated biphenyl (PCB) levels were similar to levels measured in fish caught before the oil spill.