In the 1967 film, "The Graduate," new college graduate Ben, played by Dustin Hoffman, gets some career advice from a family friend, Mr. McGuire.

"I just want to say one word to you -- just one word," McGuire says. "Plastics. There's a great future in plastics."

Or, maybe not.

Today from 6:30-8 p.m. the Center for Alaskan Coastal Studies starts its 25th annual CoastWalk with a kickoff at its CACS headquarters on Lake Street. Volunteers can sign up to clean and monitor a section of Kachemak Bay and lower Cook Inlet shorelines. Homer City Council member David Lewis and Fresh Sourdough Express owner Donna Maltz will talk on ideas to reduce plastic bag and other product use. Irene Root of Something New Creations shows recycled art, clothing and plastic alternatives, too.

Rod Pfleiger, a representative of the Alaska Cruise Association, will speak on what the cruise industry is doing to keep plastics out of the ocean. He'll be available to address concerns about cruise ship visits to Homer next year.

Pfleiger also brings to the kickoff and demonstrates a "bulb eater," a device that crushes old fluorescent tubes and filters out toxic mercury. The Kenai Peninsula Borough has a bulb eater, but the cruise association donates such devices to Alaska communities that don't have them.

This year's theme, "Life with Plastic: It's not Fantastic," considers the dark side of the modern petrochemical miracle. What happens when plastic bags, fishing line, drink bottles, food containers and other plastic products get into the world's oceans?

Although plastic eventually breaks down into small particles, it doesn't disappear. Some scientists estimate there are six pounds of plastic for every pound of plankton. Pollutants like oil can stick to plastic and, if eaten, magnify the effects of the pollutant, said Katie Spellman, CoastWalk coordinator.

Animals can get entangled in plastic rope or other material. Some marine animals like albatrosses eat plastic they think is food.

"You find a beached bird that's full of plastic water bottle tops," Spellman said.

Plastic material has consistently ranked as one of the top 10 items collected in prior CoastWalk beach cleanups, either for bags or beverage containers.

"The idea is to really stop it before it gets into the ocean," Spellman said. "Be more cognizant of how we're taking care of trash, whether sitting around the campfire on the beach or anywhere around the bay," she added.

A lot of the bay's plastic comes from shoreline recreation like that, but much comes from as far away as China or Russia. Local beach cleaners have collected plastic bottles in every major world language. As the sea gives it also takes.

"The plastics we're using on our beaches could end up in Japan or Korea," Spellman said.

Since 1996, CoastWalk has been part of the Ocean Conservancy's International Coast Cleanup, held every fall worldwide. CoastWalk volunteers have been cleaning beaches since 1984, back when some people in Homer used the beaches to dump old cars and other trash. CoastWalk is as much about monitoring coastal changes as hauling away unsightly litter. Volunteers document activities like ATV and other human use, invertebrate habitat, birds and other wildlife seen and changes in the coast such as bluff erosion.

"You can really see the changes in time and the biodiversity," Spellman said of the quarter-century of citizen science.

Several schools, including McNeil Canyon Elementary School and Homer Middle School, have made CoastWalk part of their classroom activities, with students volunteering in the cleanup and monitoring.

Volunteers can spice up their cleanup by using the odd debris they found to make art for the 2009 CoastWalk Art Contest, whether photography, sculpture, collage or wearable art. Awards will be given at the CACS annual meeting on Oct. 7 in youth and adult categories.

New this year for CoastWalk is an awareness that if you're not part of the solution, you're part of the problem. In the past, volunteers have used heavy plastic bags to collect trash.

This year, Loopy Lupine, a local recycled products company, has donated compostible trash bags.

"Our big theme is plastics prevention," Spellman said. "Would we be walking the walk if we used regular old trash bags? No."

CoastWalk continues through Sept. 30. Volunteers do not need to attend the kickoff today to sign up. To join CoastWalk, or for more information, visit www.akcoastalstudie.org or call 235-6667.

Michael Armstrong can be reached at michael.armstrong.@homernews.com.