It is one of the best-known, if brief, exchanges in movie history. In “The Graduate,” recent college graduate Benjamin Braddock wants nothing to do with his parents’ superficial world. At a party, he is briefly cornered by a friend of his parents, Mr. McGuire, who seeks to offer the young man some advice.

“I just want to say one word to you, just one word,” Mr. McGuire says in the 1967 movie.

“Plastics,” he says.

“Exactly how do you mean?” Benjamin asks.

“There’s a great future in plastics. Think about it. Will you think about it?”

Plastic has become ubiquitous in our lives, from shopping bags and food packaging to clothing and facial cleansers. It also has become ubiquitous in our oceans, harming wildlife and water quality.

A recent study found there are more than 5 trillion pieces of plastic, many smaller than a grain of sand, floating in the world’s ocean. The authors of the study, published by the journal PLOS ONE, warn this may be only a tiny fraction of the plastic in the ocean because it didn’t account for plastic on shorelines, on the seabed, throughout the water column or ingested by animals.

In Maine, the Marine Environmental Research Institute, a nonprofit based in Blue Hill that studies ocean pollution, has found similar problems. Microplastic comes from larger pieces of plastic that break down in the sun and water or directly from hygiene products, such as face and hand soap and toothpaste that contain microbeads, which are washed into wastewater and are too small to be removed by treatment plants. Microplastic fibers also wash off fleece jackets and clothing.

Plastic is especially troublesome because it soaks up chemicals, such as flame retardants and PCBs. Susan Shaw, MERI’s founder, director and principal scientist, has spent years studying those chemicals and said they can suppress the immune system and cause cancer and endocrine disruption.

Microplastics carry these toxins all the way up the food chain, from phytoplankton to harbor seals, she said.

A study published in the journal Current Biology in 2013 found, for the first time, that ingestion of microplastics caused biological problems in organisms — lugworms, in this case. The worms ate less sediment, and mortality increased. It was a warning sign of the potential consequences to other organisms.

Fortunately, lawmakers in Maine and other states are taking steps to ban microbeads. In Augusta, LD 85, sponsored by Republican Sen. Tom Saviello of Wilton, sailed through the Environment and Natural Resources Committee earlier this month. The bill would phase out the sale and manufacture of personal care products containing synthetic plastic microbeads beginning in 2017.

“If something is bad, I want it gone,” said Saviello, who worked with industry on the phaseout.

In addition to Maine, lawmakers in California, New York, Ohio and Minnesota are considering similar legislation. Illinois banned microbeads last year. Several major manufacturers, including Unilever, Johnson & Johnson and L’Oreal, have pledged to phase out use of plastic microbeads in their products and search for alternatives, according to the National Oceanic and Atmospheric Administration.

Maine’s action to ban microbeads won’t make the difference on its own, but by joining other states in pushing manufacturers to stop using them, it will have played its part in cutting back on this plastic pollution.

The Bangor Daily News editorial board members are Publisher Richard J. Warren, Opinion Editor Susan Young, Deputy Opinion Editor Matt Junker and BDN President Todd Benoit. Young has worked for the BDN...