Which of the following is a main contaminant of water near Kalamazoo?

In the context of Kalamazoo, one of the most notable environmental concerns has been related to oil spills, particularly the significant incident that occurred in 2010 when a pipeline burst and released a large volume of crude oil into the Kalamazoo River. This incident highlighted the seriousness of oil spills as contaminants of water bodies, leading to severe ecological impacts and prompting extensive clean-up efforts. Oil spills can harm aquatic ecosystems, affect wildlife, and lead to long-term environmental damage.

While other options like nitrates, phosphates, and sulfides can also be contaminants, they may not have the same historical significance or immediate impacts associated with the water quality issues in Kalamazoo as the oil spill does. For this reason, oil spill is correctly identified as a main contaminant in the area.