Toxic chemicals in Puget Sound

Much of the pollution that enters the environment comes from the small but steady release of toxic chemicals contained in everyday products, such as brakes on cars, flame retardants in furniture, softeners in plastics, and building and roofing materials. As products are used and disposed, the toxics they contain can enter rivers, streams, lakes, and Puget Sound.

Exposure to these toxic chemicals can cause harm to human health and the animals exposed to them in the environment. Infants and children are especially at risk. Some toxic chemicals impair development, some affect reproduction and disrupt body chemistry, and some cause cancer. Known as persistent bioaccumlative and toxic chemicals (PBTs), they can linger in the environment for decades and be found in the fatty tissue of people and animals long after their use has been stopped or products banned.

Our toxics efforts focus on identifying priority toxic chemicals and developing plans to reduce or eliminate their use, or to mitigate their impacts on people and the environment. Our approach is:

Prevention: Reduce the use of toxic materials and prevent them from entering into use in homes and industry.
Management: Clean up contaminated water bodies with source control planning efforts.
Research: Use monitoring data to inform decisions and prioritize actions.

Studying how toxics get into Puget Sound

Research boat in the sunset on Puget Sound

Our scientists analyze how chemicals get into Puget Sound and identify the sources of the chemicals. This allows us to prioritize actions for prevention and cleanup. We conducted a series of multi-year studies to quantify the amounts of 17 toxic chemicals or chemical groups delivered to the Sound from known pathways. The pathways studied were:

Surface runoff
Groundwater
Ocean exchange
Wastewater treatment plants
Atmospheric deposition

Puget Sound Toxics Assessment

We assessed selected toxic chemicals in 2011. A long-term study outlined the loading pathways, estimated volumes coming from various sources, and provided technical information to help develop toxic-chemical-control strategies for the Puget Sound basin.

Toxics projects 2011 - 2018

Roughly $10.6 million of a $21 million federal National Estuary Program grant in 2011 provided investments for pollution prevention, management of toxic chemicals, and research on Puget Sound toxics through 2018, based on the Toxics Assessment recommendations. A report outlining these projects — including successes, challenges, and recommendations for further work — is available.

Toxics projects 2011 - 2018 report

Surface runoff most common pollutant pathway

The most common delivery pathway toxic chemicals take to reach Puget Sound is through polluted surface runoff — also known as stormwater. Rain hits roofs, roads, developed areas, and other hard surfaces and runs into storm drains. It then goes mostly untreated into lakes, streams, and rivers that drain to Puget Sound.

The highest concentrations of toxic pollutants come from developed areas of residential, commercial/industrial, and agricultural land uses. These types of land uses have a large amount of impervious surfaces, like pavement and roofs that prevent rainwater from soaking directly into the ground. This creates the conditions for these chemicals to be carried away in runoff.

Targeted chemicals of concern

Scientists assessed the relative hazards posed by target chemicals in the assessment report. Results of the hazard evaluation suggest that the following chemicals are most likely to be found at concentrations of concern:

Copper, used in brake pads and boat paints.
Mercury from fluorescent light bulbs, dental fillings, and other sources.
Polychlorinated biphenyls (PCBs), from legacy products and some current paints and dyes.
Polychlorinated dioxins and furans (PCDD/Fs), compounds formed during combustion.
The pesticide DDT (and its metabolites DDD and DDE).
Polycyclic aromatic hydrocarbons (PAHs) from petroleum, creosote, and wood combustion.
Bis(2-ethylhexyl) phthalate (DEHP), a plastic additive.

Petroleum-related compounds from motor oil drips and vehicle leaks account for slightly less than two-thirds of the total estimated initial release of petroleum-related compounds.

Other chemicals studied in the assessment, such as PBDEs and many that have yet to be studied, are also present at levels of concern, but hazard thresholds for most compounds are lacking.

Ongoing monitoring of toxic chemical sources

We began studying toxic chemicals in roofing runoff in 2012.The final report of that first study is Roofing Materials Assessment: Investigation of Toxic Chemicals in Roof Runoff from Constructed Panels in 2013 and 2014.

The Washington Stormwater Center at the Washington State University Puyallup Research and Extension Center continues the investigation, conducting water samples and bioassays of roof runoff water.

Quality Assurance Project Plan - Roofing Materials Assessment: Investigation of Toxic Chemicals in Roof Runoff is the plan for the study.
Investigation of Toxic Chemicals in Roof Runoff (PDF) is a presentation from the Washington Stormwater Center on the results.

An investigation of the primary sources of copper and zinc in a commercial-industrial watershed, the land use with the highest contribution of these metals, is underway. Copper and Zinc in Urban Runoff: Phase 1 – Potential Pollutant Sources and Release Rates is the report from the first phase of that study. During Phase 1 of the study, we calculated the potential loading from various sources of copper and zinc using literature release rates.

Poster: Copper and Zinc in Urban Runoff: Potential Pollutant Sources and Release Rates summarizes the Phase 1 report.

Phase 2 measured copper and zinc in urban runoff in the winter of 2017 - 2018, studying runoff from building roofing and siding, chain-link fencing, streetlights, and roof gutters. These sources were determined in Phase 1 to have the highest potential to contribute copper or zinc to the environment. They also had the greatest variability around estimated loading values.

Copper and Zinc in Urban Runoff: Phase 2 — Rainwater Washoff Monitoring is the report from the Phase 2 study.
Quality Assurance Project Plan: Copper and Zinc in Urban Runoff: Phase 2 – Rainwater Runoff Monitoring describes the Phase 2 study.
Copper, Zinc, and Lead Concentrations at Five Puget Sound Marinas reports on a study to assess current levels of metals in marinas throughout the Sound to provide a baseline against which to gauge effectiveness of RCW 70.300.020, recent legislation phasing out copper-containing boat paint.
Quality Assurance Project Plan: Copper, Zinc, and Lead in Five Marinas within Puget Sound is the plan for the study.

Screening for PAHs and Metals in the Puget Sound Basin at Aquatic Habitats Adjacent to Mainline Railroad Tracks reports on a recent study to assess PAH levels in aquatic environments near railroad tracks.
Quality Assurance Project Plan: Screening for PAHs and Metals in the Puget Sound Basin at Aquatic Habitats Adjacent to Mainline Railroad Tracks is the quality-assurance plan for the study.

Other studies describe toxics in the Sound

Puget Sound Regional Toxics Model: Evaluation of PCBs, PBDEs, PAHs, Copper, Lead, and Zinc
Sediment Quality in Urban Bays describes studies of chemical contaminants at the bottom of Puget Sound.
The North Olympic Peninsula Regional Background Study looks at background levels of contaminants in marine sediments of the north Olympic Peninsula, from Port Angeles to Port Townsend.
Our partners at Washington Fish and Wildlife’s T-BiOS routinely sample Puget Sound biota for toxics, informing the Puget Sound Partnership’s Toxics in Aquatic Life Vital Sign by providing key recovery metrics.