TULUM, Mexico (AP) — Scraping smelly sargassum seaweed off some beaches on Mexico’s resort-studded Caribbean coast has become not just a nightmare, but possibly a health threat, for workers doing it — with the amounts washed ashore this year apparently from mountains not mounds.
The decomposition of sargassum, which is actually algae, generates hydrogen sulfide gas. In small amounts in open spaces, it’s little more than an annoying smell: sulphurous, like rotten eggs.
But in the amounts seen in once-paradise beach towns like Playa del Carmen, Tulum and Xcalak, scientists say it can be dangerous for workers with respiratory problems as they rake up the seaweed without masks in the scorching heat. This year appears to be on track to be worse than even the peak Sargassum year of 2018.
Ezequiel Martínez Lara is one of thousands of laborers who work six to eight hours a day lifting mounds of Sargassum into wheelbarrows with pitchforks, then hauling them from the beach to a growing pile on a nearby street.
Martínez Lara used to earn up to $50 a day guiding sport fisherman on catch-and-release fishing trips, but now earns less than half that amount for collecting around 40 wheelbarrows of Sargassum each day.
It’s a Sisyphean task on a beach north of Tulum, where huge mats of seaweed float just offshore.
“If we clean everything today, tomorrow there will be more,” said another worker, Austin Valle.
But workers like Martínez and Valle are exposed to more than the scorching sun, says Rosa Rodríguez Martínez, a biologist in the seaside town of Puerto Morelos who studies reefs and coastal ecosystems for the National Autonomous University of Mexico.
“At university, we started measuring the amount of gas that sargassum produces when scraped,” Rodríguez Martínez said. “At one location (in a pile of decomposed seaweed) it reached 56 parts per million. It is very high. Above two can be dangerous for people with respiratory problems.
“I ran” from the spot, she said.
Martínez Lara does not have the luxury of avoiding hydrogen sulphide gas. Like nearly every other sargassum worker on the coast, he has no mask, gas sensor, or medical attention. He works day to day for the owner of the house in front of the beach.
“When sargassum rots, it gives off a very strong smell of acid, and it’s very embarrassing when you breathe it; it hurts a lot, ”said Martínez Lara. He said he’s taking simpler precautions.
“We try to clean it (from the beach) as quickly as possible … to take it out when it’s as fresh as possible,” he says.
A 2019 article in the Journal of Travel Medicine includes the ominous warning: “More chronic exposure to these gases can lead to conjunctival and neurocognitive symptoms such as memory loss and balance disturbances, as well as non-toxic symptoms. specific such as headaches, nausea and fatigue. .”
The Florida Department of Health, on the other hand, states that “levels of hydrogen sulfide in an area like the beach, where large amounts of airflow can dilute levels, should not adversely affect the health”.
The Sargassum problem is not as serious for tourists as it is for workers. But it’s not pleasant either.
Ligia Collado-Vides, a marine botanist at Florida International University who specializes in the study of macroalgae like Sargassum, said, “If you’re swimming a bit, it shouldn’t be a hazard at all,” but added that tiny cousin jellyfish known as hydrozoans often inhabit sargassum mats.
“If you’re going to play in the sargassum for a long time, you can get lots and lots and lots of hydrozoan bites and those are poisonous,” she noted, adding that long sleeves – something almost nobody door to beach – might help.
Sarah Callaway, a tourist from Denver, Colorado, was virtually confined to playing with her children in the pool outside their rented beach house.
“The property is beautiful, but we were automatically struck … by the smell,” Callaway said. “The smell is really pungent and very strong. And then, yes, we were disappointed by the amount of seaweed sargassum there is here.
“The kids tried to get into the ocean, but then they got a little overwhelmed, so we couldn’t really do the beach part, which is why we came,” she said. .
It will also impact locals who depend on the tourist trade. Hundreds of thousands of people have migrated to the coast in recent years for better paying jobs, but some may now be considering leaving.
Valle, the algae cleaner, said a friend of his in Tulum was considering giving up his snack stand business because sales had dropped so badly.
It is difficult to measure the impact on tourism. The Caribbean coast suffered a drop in visits during the coronavirus pandemic, but since Mexico never declared travel restrictions, testing requirements or mandatory mask rules, Americans kept coming.
International tourism in the country as a whole exceeded pre-pandemic levels in the first half of 2022, with 10.26 million visitors from January to June, 1.5% more than the 10.11 million tourists arrived in Mexico in the first half of 2019.
Mexico’s strongest performance was with American tourists. The number of Americans arriving by air in the first six months of 2022 was 6.66 million; i.e. 19.1% more than in the same period of 2019.
But this boom could slow down. Grupo Financiero Base noted in a research report that international tourist arrivals in June 2022 were down 13.8% from June 2019 levels. It is unclear what – sargassum, inflation or the war in Ukraine – may have caused this decline.
And overall tourism spending remains below pre-pandemic levels.
The picture is mixed because some of the more developed resorts like Cancun haven’t suffered from Sargassum as much as resorts further south, like Playa del Carmen and Tulum.
Ocean currents and islands like Isla Mujeres protect Cancun from much of the floating sargassum. Given the large number of large hotels in Cancun with huge cleaning crews and money to deploy booms, incoming sargassum is cleared faster.
The jury is still out on floating booms, intended to trap sargassum mats at sea before they reach the beach.
“When the sea is calm, all types of booms work,” Rodríguez Martínez said. “When there are waves, none of them work.”
Some tourists love the area so much that they will keep coming back.
“I will absolutely be back. We love this place,” said Jeff Chambers, a tourist from Palm Desert, Calif., who was strolling the main coastal street in Tulum. “We like things a little slower.”
Some locals like Victor Reyes, who works in real estate in Tulum, are more optimistic about the algae, noting that it’s not that bad during the winter months.
“In winter, it’s better. In November, when tourists want to come, the sargassum is gone,” says Reyes.
As bad as sargassum is for people — and Collado-Vides points out that many more studies are needed — it’s far worse for seagrass, fish and other sea life smothered by algae that sink to the bottom, break down and create oxygen-depleted or anoxic layers similar to dead zones.
“The sargassum sits there and goes down the water column so no one sees it, but basically it creates anoxic conditions,” she said.
Recounting a recent monitoring expedition, Collado-Vides said, “It’s really terrible…the amount of vertebrates, the amount of crabs, the amount of dead fish in just one square meter quadrant.”