Pregnancies. Births. Birthdays. Graduations. Anniversaries. Promotions. Retirements. Even deaths. Balloons are used to decorate, celebrate or commemorate almost every major life event.

But there's a growing awareness that balloons released to the sky come down to Earth, somewhere, as litter, 100% of the time. And that litter, in addition to polluting the environment, can be deadly to animals that eat the balloons or get tangled in them.

Volunteer trash pickups found more than 18,000 balloons, balloon pieces or balloon strings along Great Lakes shorelines between 2016 and last year. That's according to surveys from such events sponsored by environmental nonprofit Alliance for the Great Lakes.

Heightened understanding of problems tied to balloon litter has led five states to limit or ban intentional releases. At least eight others are considering restrictions.

Those who release thousands of balloons for a visual spectacle have come under particular fire: Clemson University, in 2018, after years of urging from environmental groups, agreed to stop its long-standing release of thousands of balloons as its football team took the field for home games.

A master's student at the University of Michigan wants to better understand the scope of the problem on the Great Lakes, and raise awareness about the issue at locations where large numbers of balloons are sometimes released.

Lara O'Brien, who studies in the university's School for Environment and Sustainability, created a web survey form for volunteer citizen-scientists to report balloon debris findings along the Great Lakes: when, where and what kind of debris.

"I've seen a lot of people come together, gather and celebrate graduations, weddings, other celebrations, and they release balloons — and don't really consider the consequences when the balloons come down," she said.

O'Brien cited a March study from the University of Tasmania that found balloons are the highest-risk plastic debris item for seabirds — 32 times more likely to kill them than ingesting hard plastics.

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The Alliance for the Great Lakes' shoreline cleanup program has found between 4,400 and 7,200 pieces of balloon waste on Great Lakes beaches each of the last three years — and the variation in the numbers can likely be attributed to the number of volunteers in a certain year, not less balloon waste, said Alliance spokeswoman Jennifer Caddick.

"It's really dramatic and troubling," she said. "It paints a picture of the bigger plastic pollution problem plaguing the Great Lakes, our oceans, and really the entire planet."

As winds generally blow west-to-east across the U.S., balloon litter is a particularly chronic issue on the Atlantic coast.

"It's a huge problem — washed-up balloons on the beach are huge," said Pamela Denmon, a U.S. Fish and Wildlife Service biologist at the Eastern Shore of Virginia National Wildlife Refuge, on Chesapeake Bay in Cape Charles, Virginia.

"Every day we could go out and pick up balloons. We actually have people that write on balloons their phone number because they want somebody to call when they find it."

Christina Trapani, a beach cleanup volunteer at the refuge, has helped track balloon waste in Virginia.

One balloon found in Chesapeake Bay was marked as coming from Kansas, about 1,400 miles away, and was still partially inflated, she said.

In December 2012, an elementary school class in Derby, England, released 300 balloons with notes. The balloons were found in The Netherlands, Denmark — and one made it to New South Wales, Australia, more than 10,500 miles away, three months later.

"People don't think about it as being litter," Trapani said. "(But) if it goes up, it's going to come down sooner or later."

And if it comes down in or along an ocean, it can look like food to a seabird, a sea turtle, dolphin or other marine animal.

"We would do a necropsy on a bird or turtle or other marine mammal and it would have entangled balloon ribbon all throughout its guts," Denmon said.

She also has encountered dead seabirds, hanging from power lines or choked around the neck by balloon strings.

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Balloon restrictions are still rare

Only five U.S. states have laws regulating the intentional release of balloons: California, Connecticut, Florida, Tennessee and Virginia. At least eight other state legislatures are considering such laws: Arizona, Connecticut, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island and Maine.

A number of cities also have ordinances against intentional balloon releases, including San Francisco, Baltimore and Louisville, Kentucky.

While those actions are helpful, the nature of balloons limits how effective restrictions can be, Trapani said.

"There might be balloon bans in some places and not in others," she said. "But it doesn't matter when you release it — they can end up in these places."

Danielle Vosburgh and her sister, Chelsea, on their frequent walks along the beach near their home in southeast Florida, kept finding balloons. Online research led them to learn about balloons' harm to wildlife. It also led them to comments from the balloon industry referencing "biodegradable" and "safe" balloons.

The sisters formed the environmental nonprofit Balloons Blow, "just to put the facts out there because a lot of the information out there was coming from the balloon industry, pushing their 'biodegradable' propaganda," Danielle Vosburgh said.

While many balloon types will ultimately break down, the degradation process can take months or even years, meaning the risk to animals remains for all that time.

On Balloons Blow's website, the sisters have a "backyard biodegradability test," where they placed two latex balloons that washed up on the shore in 2012. More than five years later, the broken down balloons are still visible — and their ribbons are in great shape, photos show.

"They are almost 7½ years old now," Danielle Vosburgh said. "They are breaking down a little bit, but they're still here."

Balloons Blow also works with other organizations to get large-scale balloon releases stopped.

Clemson University, in 2018, ended a 35-year tradition of releasing thousands of balloons as its football players entered their stadium for home games.

One of the remaining big balloon-releasing events in the country is in Balloons Blow's and others' sights: The Indianapolis 500, which, since 1947, has included a "Balloon Spectacle," where up to 40,000 colorful balloons are released to the sky before the race.

"Hopefully, when people become aware, they will want to become part of the solution, whether it's illegal or not," Vosburgh said. "Do we really need laws to be responsible citizens?"

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Don't demonize balloons, industry says

The balloon industry squirms a little whenever a state or city talks about banning balloons.

The Balloon Council, a Trenton, New Jersey-based organization of balloon retailers, distributors and manufacturers,has spent more than $1 million nationwide lobbying to change or stop proposed laws to restrict balloons.

"We've never supported or sponsored any balloon releases," council executive director Lorna O'Hara said.

"We want people to continue to be able to use balloons, enjoy them, and then dispose of them properly."

O'Hara says her group is "not opposing balloon release bans, but we would prefer educational programs," encouraging actions such as putting all helium-filled balloons on weights and using biodegradable strings, or no attachments at all.

"When we oppose a bill, we might only oppose certain lines in the bill," she said.

"We're concerned about the negative stigma associated with the product. Bans on the sale and use side, we oppose that, because we have a lot of small operators — decorators, a lot of women-owned, family-owned small businesses — that would really be harmed."

Trapani said she's encouraged that the word is getting out on balloon litter, and behaviors are changing.

"The bottom line is, when you let go of a balloon, you're littering," she said. "You wouldn't dump a bunch of uninflated balloons on the ground."

Follow Keith Matheny on Twitter: @keithmatheny

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