Green Room: Pollutant Of The Month – Nitrates

Nitrates can cause detrimental environmental and health impacts. Learn more about nitrates, and how we can keep nitrates from polluting our watersheds and oceans, in the article below.

What are nitrates?   

Nitrates are chemical compounds containing nitrogen and oxygen. Nitrates are found in many foods (both naturally and as additives), including deli meats, hot dogs, spinach, and carrots. Nitrates are also used for industrial purposes and in explosives. Importantly, nitrates are used in fertilizers for many gardening and agricultural practices. Nitrogen-containing fertilizers can provide plants with the nutrients needed to maximize growth.

Impacts of Excessive Nitrates

Excessive amounts of nitrates can cause harm to local environments. During the rainy season, excess nitrates from local gardens, farms, manufacturing facilities, etc. can mobilize into stormwater runoff and wash down storm drains. Eventually, nitrates travel through local creeks, watersheds, and into the ocean. When nitrates deposit into bodies of water, this can proliferate the growth of algae and aquatic plants, as nitrates provide necessary nutrients for this vegetation. However, large growths of plants/algae can reduce the amount of available oxygen in the waterway, which results in limited oxygen availability for fish and other aquatic species. This can lead to the death of species in the creek, watershed, and/or ocean. Furthermore, some types of algae produce toxins that can cause illness and/or death in plants, animals, and/or humans that visit the waterway or surrounding area.

Additionally, when excess nitrates are washed into the local environment, this constituent can contaminate local drinking water supplies. Nitrates in groundwater and drinking water can cause severe adverse health outcomes in humans. Nitrate exposure is associated with rashes, stomach/liver illness, respiratory issues, and neurological impacts. Studies have also found that exposure to nitrates is associated with some types of cancer, thyroid disease, and neural tube defects.

What can I do to reduce nitrate pollution?

The best way to reduce nitrate pollution is to use mulch and compost as soil amendments in your garden, not chemical-based fertilizers. If you must use chemical-based fertilizers, apply fertilizer only when necessary, and do not overwater/over-irrigate the planted area. Additionally, picking up your pet’s feces with a bag minimizes nitrate pollution, as feces is also high in nitrates.

The City of Goleta does not use herbicides, pesticides, or fertilizers in public parks, open spaces, or the right-of-way. This practice is based on elements of the Goleta General Plan/Coastal Land Use Plan, the City of Goleta Stormwater Management Plan, and guidance from City Council to City staff. The City invites the Goleta community to adopt this practice as well.

For more information, please visit the U.S. Environmental Protection Agency website on nitrate pollution: