Like nutrients, chemical contaminants enter the system from point and nonpoint sources. For example, the manufacturing processes we have come to rely on for products often involve the use of harmful chemicals. Also, many everyday household cleaning and pest control products contain toxic ingredients. Exhaust from automobiles and emissions from fossil fuel power plants also contain toxic chemicals. Nonpoint sources , such as urban and suburban storm water runoff, are significant sources of chemical contaminants.
Air pollution is a source of chemical contaminants.
The primary sources of chemical contaminant loads to the Bay vary depending on the chemical. Sources of chemical contaminant loads vary by watershed. In order to reduce chemical releases, Bay managers are working to identify and target sources of chemical contaminants. Chemicals travel through the watershed and are eventually deposited in the Bay or rivers. For example, oil and grease from a parking lot can be washed down a drain by stormwater and into a stream, eventually leading to the Bay.