Copper and other pollutants threaten marine life

by Lisa Stiffler , Three Sheets Northwest

April 20th, 2009

 Fresh antifouling paint dries on the bottom of a large powerboat. The copper in the paint has been shown to be harmful to salmon and other marine life. Copper can be effective in keeping algae, barnacles and other pests that plague the bottom of boats at bay. The trouble is that it doesn't always stay put, leaching into the water where at even miniscule amounts, the seemingly innocuous metal can harm salmon. And the boatyards where vessels are scraped, blasted clean and painted are a source of copper and other pollutants.

State regulators are preparing to update a permit restricting how much metal, grease, oil and other
chemicals can be washed during heavy rains from boatyards into nearby waters, including Puget Sound.
Copper is the pollutant of most concern, followed by zinc, which is also used in marine paints, as well as to protect metal boat parts such as props and shafts. Lead from ballast keels is also a problem, according to a study by the state Department of Ecology, which will issue the Boatyard General Permit.

 
Years ago, tributyltin was the anti-fouling agent of choice to protect boats. But in the 1980s, the serious harm tributylin caused to marine animals became apparent and it was banned from most vessel applications. Now some wonder if the copper that replaced it needs to be phased out as well. "We, as a region, and probably a nation, have to start looking at other products (than those with copper)," said Bruce Wulkan, a storm water expert with the Puget Sound Partnership, the state agency coordinating the effort to recover the health of the Sound.

Salmon climb the fish ladder at the Hiram M. Chittenden Locks in Seattle. Copper, even in tiny amounts, has been shown to be dangerous to salmon and other marine life.

So what does copper do to salmon? It disrupts arguably their most crucial sense: their ability to smell. Research from the Northwest Fisheries Science Center, part of NOAA Fisheries in Seattle, shows that copper at tiny concentrations measuring parts per billion can diminish a coho's sense of smell. It leaves the fish more vulnerable to predators and less able to find prey or their home stream to return to for spawning.

It's not just metal pollutants from boatyards that endanger marine life. Oil and grease also threaten fish and fowl. Scientists have found deadly mutations in herring when their eggs are exposed to oil. The fish also may suffer from impaired immune systems.

Another category of pollutants detected by Ecology coming from boatyards are called phthalates. These ubiquitous industrial chemicals are added to plastics to make them softer and more pliable. Suspected sources from boatyards include their use in PVC that's part of pipes, fittings, sheeting and wire coatings, as well as in adhesives.

Tarps like these are one way boatyards try to keep copper contained. Studies show that phthalates can cause developmental deformities and reduce fertility in research animals. The permit will not require monitoring for phthalates, but does include testing for metals, fecal bacteria, phosphorus and oxygen levels. The release of oils is not allowed.

Because marine creatures can be highly sensitive to the pollutants, the state is calling for boatyards to remove the chemicals to very low levels. That can be tough-and costly-particularly given that the boatyards aren't always the original source of these common pollutants, but just the last
stop as they wash from upland sites to the water. "This is a contentious issue," Wulkan said. "A lot of boatyard owners are having a lot of trouble meeting the requirements."