The Pelc family from Pennsylvania spread out over a section of sand to enjoy a warm, sunny February afternoon at Bathtub Beach.

Also spread out on one of their beach towels was an array of sunscreens: some in tubes, some in aerosol cans, some specifically for kids and all but one containing two chemicals — oxybenzone and octinoxate — researchers say kill coral reefs.

Sunscreens containing those chemicals have been banned in Key West and Hawaii, in January and July, respectively. Now, Florida Sen. Linda Stewart, an Orlando Democrat, has filed legislation (Senate Bill 708) to ban them in the Sunshine State unless the user has a prescription.

More: Key West bans sunscreen with coral-damaging ingredients

Andy Pelc said he'd be likely to switch to a reef-friendly sunscreen just because it's better for the environment.

"And if I didn't have a choice" because of a ban, he added, "of course, I'd use it."

A little dab will do

Oxybenzone “poses a hazard to coral reef conservation and threatens the resiliency of coral reefs to climate change,’’ according to a study published in the February 2016 issue of the "Archives of Environmental Contamination and Toxicology."

When you swim with sunscreen on, the chemicals can seep into the water and be absorbed by corals, disrupting reproduction and growth. The corals turn white and die, a process known as "bleaching."

Even if you don't go in the water, sunscreen that's sprayed or rubbed on can get in the sand and be washed into the ocean.

Each year, about 14,000 tons of sunscreen end up in the ocean, according to a different study published in the same "Archives" edition.

The equivalent of one drop of oxybenzone in 6½ Olympic-sized swimming pools can damage corals, according to research by Haereticus Environmental Laboratory in Virginia.

360-mile reef

The Florida Reef Tract is a series of coral reefs stretching 360 miles from the tip of the Florida Keys to the south side of the St. Lucie Inlet in Martin County.

More:Best snorkeling spots on the Treasure Coast

It's the largest reef system in North America and the third-largest in the world, according to Ocean Conservancy's "Currents and Crossroads" report issued Feb. 6.

The Florida Department of Environmental Protection says the state's coral reefs:

Provide habitat for 6,000 marine species

Protect South Florida's shorelines from storms

Generate $3.4 billion to the economy

Support 36,000 jobs

More: State law protects Florida's coral reefs

Banning reef-harming sunscreens won't solve all the problems facing Florida's reefs, "but they can't hurt and might help," said Joshua D. Voss, a scientist at Florida Atlantic University's Harbor Branch Oceanographic Institute at Fort Pierce who's done extensive research on the Treasure Coast's nearshore and offshore coral reefs.

More: Coral bleaching coming our way

"Dealing with water quality and climate change should be the focus," he said, noting Lake Okeechobee discharges can cover Martin County coral reefs with sediment and kill them. "But getting rid of sunscreen with reef-damaging chemicals is the low-hanging fruit. If we can ban them, when there are plenty of better alternatives, why wouldn't we?"

Growing concern, business

Oxybenzone and octinoxate are typically found in sunscreens that work by creating a chemical reaction to change ultraviolet (aka UV) rays into heat and releasing the heat from the skin.

The alternative, mineral sunscreens, usually contain titanium dioxide and/or zinc oxide and work by sitting on top of the skin to deflect damaging UV rays.

Chemical sunscreens are by far more common on store shelves. Oxybenzone was found in two-thirds of the products surveyed in 2018 for the Environmental Working Group's annual sunscreen guide.

But the number of mineral-based sunscreens had grown 41 percent since 2007, the guide also found.

Traditionally made primarily by small, niche companies, reef-friendly products are now being offered by more major sunscreen makers, said Jordan Schwartz, owner of Ohana Surf Shop on Hutchinson Island in Stuart.

"They have to" make the switch, Schwartz said, "if they want to do business in Hawaii; and believe me, they want to do business in Hawaii."

More:Old freighter to become artificial reef off St. Lucie County

The sunscreen shelves at a Treasure Coast Walgreens store included mineral sunscreens by such brands as Neutrogena, Alba Botanical and Australian Gold.

"I don't get a lot of customers asking for reef-safe sunscreen," said Bruce "Spunky" Strunk, owner of Spunky's Surf Shop in Fort Pierce. "But there are more now than there were a year ago. And I expect there'll be even more as more people learn about the issues."

Skin cancer threat

Not everyone is behind the ban.

The American Academy of Dermatology says oxybenzone and octinoxate have not been proven to be toxic to the environment, and taking sunscreens with them off the market could lead to more people developing skin cancer.

"There is concern that banning these sunscreens will decrease use," Dr. Sarah Cerminara, a dermatologist at Romagosa Dermatology in Stuart, said in emailed replies to TCPalm's questions.

"At this point, the evidence for the association is a lab finding," Cerminara said, "and proving this in an actual reef ecosystem is difficult, given confounding variables such as global warming, pollution and overfishing."

Unprotected sun exposure is the most preventable risk factor for skin cancer, Cerminara said. The more sun protection options people have, the more likely they will be to find one they'll use regularly.

"I always tell people that the best sunscreen is the one you will wear every day," Cerminara said. "I do not support a ban decreasing access to safe and effective over-the-counter ingredients."

Protect your skin AND coral reefs

Avoid: oxybenzone and octinoxate

Look for: mineral-based with zinc oxide and/or titanium dioxide

A list of reef-friendly sunscreens compiled by Consumer Reports includes:

Well at Walgreens Moisturizing Lotion

Badger Active Unscented Cream Sunscreen

California Kids #Supersensitive Lotion

Florida-based alternatives include: