Digging at Alaska's declining salmon returns: Is plastic part of the problem?

Do you remember this scene from the 1967 film, "The Graduate," with Dustin Hoffman playing a baffled new college grad named Benjamin, getting some pushy career advice at a noisy family gathering:

Mr. McGuire: I just want to say one word to you. Just one word.
Benjamin: Yes, sir.
Mr. McGuire: Are you listening?
Benjamin: Yes, I am.
Mr. McGuire: Plastics.
Benjamin: (Deadpan) Exactly how do you mean?

Plastics, here, were a metaphor for everything Benjamin and his generation didn't want to become. Whether you liked the film or thought it insignificant, audiences understood the metaphor.

But plastics, we have become. Dating all the way back to 1869 when John Wesley Hyatt developed celluloid, American and international chemists have been cooking up cheap, flexible, durable and chemically resistant materials to replace what Mother Nature gave us to work with-paper, metal, wood, stone and glass.

Heather Rogers writes in A Brief History of Plastic,  "...with plastic 'the hierarchy of substances is abolished: a single one replaces them all: the whole world can be plasticized.'"

And so for decades, industrial chemists have poured, baked and rolled into production a panoply of plastics: polypropylene, polyurethane, lycra, super glues and epoxies, fiberglass, polyester, Dacron, formica, Styrofoam, Tupperware-the list seems endless.

A substance that makes these various plastics flexible is phthalate. Now we realize that because of their chemical structure, phthalates don't bond with plastics and are easily released into the environment. We are bathed in them. An oft-noted CDC study of 289 men in 2000 found phthalate levels in every single person tested.

Studies at universities and medical schools are ongoing to understand their effect on living things; at toxic levels, they are suspected of disrupting hormones and causing genital defects, breast and prostate cancer, brain alterations during development and obesity and diabetes. Not a pretty picture.

John Kennish is an environmental analytic chemist who has been teaching at UAA for 34 years. As a young man, he fled New Jersey for graduate school in Oregon. Eventually Alaska's open space and fine fishing lured him north.

Over his long academic career, he's been researching how fish react to pollution, how trace levels of metals move in the environment and the role of fatty acids in diseases affecting Alaska Natives.

Last year, Kennish won some campus stimulus funding, called the Innovate award, as seed money for a research project. He and collaborator Patty Zwollo of the College of William and Mary wanted to try and quantify the effects of marine phthalates on the immune system of trout, genetically linked to salmon.

They worked at Elizabeth Lake, an island off the western tip of the Kenai Peninsula, where waves from the Gulf of Alaska pound its shore and push ocean debris over a mile inland to a small pond.

What you see on the shoreline is a massive collection of pebble-sized and smaller particles of plastic, every color of the rainbow. Deeper inland, floating as sheen on the pond surface, is a rainbow-colored film.

Abundant small pieces of plastic are a hazard because foraging fish, birds and mammals can mistake it for food. Further, as the plastic pieces remain exposed, they continue to degrade from the sun, wave action and microbial decay.

What do they release? Their phthalates.

Kennish and Zwollo are looking at six of them, but we'll just talk about one, the most common: DEHP. The pond water at Elizabeth Island revealed large amounts, both in the middle at a meter's depth and on the surface at the back of the pond.

Kennish and undergraduate student Sharene Ali also tested phthalate concentrations in three Alaska food sources and a regional bird: clams, halibut, coho salmon and the tufted puffin. Phthalates were found in all, but the highest levels were in clams, which simply assimilate the compounds while other animals metabolize them.

Just getting to these results was challenging for the scientists because tissue samples were stored and bathed in typical lab solutions that are full of phthalates. They are ubiquitous in all lab and medical environments. Testing eventually had to be done in glass, and as phthalate-free as possible.

Preliminary results in the lab indicate that when mouse cells are exposed to DEHP, immune system cell division slows down. The same thing happens in trout, potentially leaving them more vulnerable to disease. The decrease is dose-dependent, meaning the higher the concentration of DEHP, the fewer cells produced. Levels in Elizabeth Lake were three times higher than other places tested. Kennish is using these early results to apply for more grant funding to continue the work.

Trout are in the salmon family, and salmon returns for some of Alaska's major wild runs have seen devastating declines in recent years. Researchers, fishermen, marketers, and a lot of other Alaskans, want to know why.

"We think these kinds of exposures may affect the actual survival of juvenile salmon in our marine environment," he said.

NOTE: A version of this story appeared in the Anchorage Daily News on Jan. 27, 2013.