WHEN I first heard the news about the earthquake and subsequent tsunami that occurred last March in Japan, I felt an immediate pang of sadness for all that would be lost in that disaster. It was only later that an unsettling aftershock hit me: What will happen to all the debris washed out to sea?

It's been one year since that tragic event. And while the human toll is still being felt, we know very little about what has become of the millions of tons of debris generated by that disaster.

The heartbreaking variety of debris (homes, fishing vessels, small freighters) makes it impossible to know how much of it is still afloat, has sunk or degraded. And while not all of the debris from the earthquake was washed into the Pacific Ocean, the impact of tsunami debris on the ocean's health is potentially huge.

Debris washing ashore could introduce invasive species and damage important habitat areas like kelp forests and coral reefs.

Abandoned fishing gear and other items that pose an entanglement risk could threaten seabirds and migratory Pacific species like bluefin tuna, green and leatherback sea turtles, mako and blue sharks and whales that use the North Pacific waters to forage, breed and migrate.

If the tsunami debris reaches Washington's beautiful coastline, it could have immediate impacts not just on wildlife, but on human and economic health.

While it's highly unlikely that the tsunami debris is contaminated with radiation, some items, like car parts and 55-gallon chemical drums, could leak toxic compounds.

Debris in the water can pose a hazard to surfers, swimmers and scuba divers, and it can get caught in the propellers, motors and other machinery of commercial vessels.

While there's not much we can do to prevent the tsunami debris from reaching our shores, we can take steps to reduce the impacts.

The National Oceanic and Atmospheric Administration (NOAA) and its partners are leading efforts to collect data, assess the debris and possible impacts based on sound science, and protect our natural resources and coasts.

Ocean Conservancy is partnering with NOAA to help educate the public and provide direct information on the tsunami debris to our global network of volunteers. Pacific-coast residents should certainly continue to enjoy beaches and the water, but we are asking people to be vigilant and report potential tsunami debris to NOAA.

It's important that we assess the potential threats of marine debris on wildlife, habitats and human health — as well as take inventory of damages once they do occur. And the coastal regions hit hardest by the debris will need funding for cleanup efforts.

We can also do our part to reduce ocean trash by limiting use of disposable cups, bottles, straws and other one-time-use items. We can also pick up litter and properly dispose of our own trash, no matter how far away the ocean may seem.

We're doing our part to work toward a vision of trash-free seas. Over the past 26 years, more than 9 million volunteers have collected 154 million pounds of trash from coasts and waterways all over the world as part of our International Coastal Cleanup.

We're also looking for solutions beyond individual action by working with companies such as Coca-Cola and Covanta Energy to reinvent business in order to reduce the amount of trash created in the first place.

The debris from the Japanese tsunami is an unpreventable and relatively small part of the larger but also largely preventable problem of ocean trash. The truth is that a tsunami's worth of trash is created every year simply by the things we buy, use and throw away.

By removing and reducing the amount of trash in our ocean and waterways, we can help ensure that the ocean is more resilient in the face of unavoidable natural disasters.