No matter how many times he participates, Michael Carberry is always astounded at the amount of trash collected on Hawai'i beaches during Global Coastal Cleanup Day.

"I've been doing it five years and it's a good way to give back to the environment," said Carberry, a Hawaiian Electric employee. "Two years ago we picked up about 200 spare tires and every year in just a few hours we collect enough trash to fill a 30- or 40-foot bin. Never fails."

Carberry and about 90 other HECO employees and their families and friends will collect trash tomorrow morning along a mile of Kahe Point's Electric Beach. They'll be joined by thousands of other people in Hawai'i and many more around the world during the annual event.

Last year, 4,382 volunteers collected 72,224 pounds of trash from more than 160 miles of coastline in Hawai'i. Globally, 378,000 volunteers from 76 countries and 45 states cleared more than 6 million pounds of trash from oceans and waterways.

The biggest polluters? Smokers.

In Hawai'i, 72,254 cigarettes and cigarette filters were collected last year — 44.2 percent of all trash items collected, according to The Ocean Conservancy, which organizes the event and compiles the information on what is collected.

Caps and lids for various drinks were next on the list at 13 percent, while food wrappers, cups, plates and other type of picnic items, along with bags, rounded out the top five types of debris on Hawai'i beaches.

Sharon Higa, spokeswoman for HECO, said abandoned car parts are always part of the Kahe cleanup.

"A few years ago I remember our volunteers saying they had collected enough car parts to build an entire car," Higa said.

Christina Woolaway, state coordinator for the cleanup, said about 5,000 volunteers at 25 beaches on O'ahu and 75 statewide beaches are expected to participate tomorrow.

"We're hoping to collect at least as much as last year," Woolaway said. "The one thing about this day is it gives leaders a snapshot of what's out there to deal with. Illegal dump sites. Dumped car parts. If you go to some Leeward beaches, you find burned wooden palettes with nails just sitting out there."

Woolaway said this year's total is hard to predict because of the state primary elections.

"Go vote and then collect, or collect, then vote," she said. "Election years are always tough to determine."

This year, Woolaway said, two pieces of trash are of particular interest in Hawai'i: fishing line and black plastic tubes.

"The fishing lines can be recycled and we have a list of places to do so on our Web site," Woolaway said.

"The black tubes are used as spacers for oyster farms and during storms and as such they'll often break loose and float into the main Hawaiian Islands. They end up getting ingested by birds and can be deadly. It's a big problem here."