Narrator: These bricks are made from seaweed.
The secret is sargassum,
an invasive species washing up and rotting on beaches
around North America.
Narrator: The massive waves can lead to respiratory problems
and can cost millions to clean up.
But where most people see a problem,
Omar Vazquez saw potential.
Narrator: He turns the seaweed into bricks
strong enough to build homes
that he says can withstand hurricanes.
Narrator: Omar and his family immigrated to the US
with nothing in their pockets
when he was just 8 years old.
Now, he uses his bricks to build homes
for low-income families like the Lopezes.
Narrator: Could this invention help other countries
clean up their coastlines?
We went to Mexico to see how entrepreneurs like Omar
are making the most out of a stinky situation.
Omar and his team start collecting the seaweed at 5 a.m.
Today, they're in Puerto Morelos,
a small beach town about 25 miles from Cancun.
Narrator: Hotels pay them to get the seaweed off the beach
and out of the view of tourists.
They collect about 40 metric tons of sargassum every day,
enough to fill two of these containers.
Narrator: The idea to turn seaweed into bricks came to Omar in 2018,
when more than 50,000 metric tons of sargassum
overran the coast.
Narrator: Omar makes the bricks, which he calls Sargablocks,
at his workshop 10 minutes from the beach.
Workers grind the dry sargassum into a fine powder
by smashing it with rocks.
Then they mix it with dirt,
which Omar repurposes from construction sites.
They shovel a mixture of sargassum dust and dirt
through a grate to remove any large chunks.
They mix the powder with water to form a thick paste.
The exact recipe is a secret,
but each brick is about 40% Sargassum.
Sargablocks can also be recycled again and again.
Narrator: With this single machine,
Omar can make up to 3,000 bricks a day.
He developed eight prototypes before perfecting this one.
Now, he's designing a bigger machine
that could produce 8,000 bricks a day.
He has six full-time employees making the bricks,
and some help build homes, too.
Since 2018, Omar has built more than 40 homes.
The first one is right next to his workshop.
He named it after his mother.
Narrator: When he was 8 years old, Omar left behind a home
just like this one to cross the Mexico-US border
with his mother.
Narrator: They wouldn't have a home of their own
for the 30 years they lived in the US.
Narrator: He finally returned to his home country for good in 2014
with just $55 in his pocket.
He used it to start a business buying and selling plants,
and he eventually saved enough money to buy this lot.
Narrator: Developing Sargablocks required a lot of trial and error.
Narrator: Omar's business is called Vivero Blue Green.
He makes most of his money selling plants
and from hotels paying him to clean up the sargassum.
He also sells his bricks and builds houses.
He has sold more than 20 homes and given away another 15.
Omar admits the houses may not be fancy,
but they are durable.
Narrator: That's good news for Elizabeth del Carmen Bonola López
and her daughters.
Their home was destroyed in a hurricane in 2021.
Omar helped them rebuild it with Sargablocks.
Narrator: Indeed, research shows that seaweed is a great insulator
that keeps homes cool in the summer
and stores heat in the winter.
Usually, Omar hears about people in need
through a friend or local.
Narrator: And there's no lack of raw material.
Over the past decade, waves of sargassum
have gotten so large, you can detect them from space.
In 2020, the Mexican government collected
19,000 metric tons of sargassum
from Quintana Roo's beaches.
In 2021, it collected twice that amount.
Narrator: Studies show prolonged exposure can make it hard to breathe.
In 2023, the Cancun Hotel Association
set aside more than $20 million to remove it from beaches.
And the problem goes beyond Mexico.
The invasive weed has spread to shores across North America
in Florida, Texas, and other parts of the Caribbean.
The exact cause of the increase isn't clear,
but some experts blame high levels of nitrogen in the sea,
a result of agricultural waste runoff and deforestation.
So now, Omar's business is getting international attention.
He's given TED Talks, appeared on "Shark Tank Mexico,"
and traveled internationally to promote his product.
Investors and businesses from over a dozen countries
have reached out to learn from him.
Narrator: Omar is exploring licensing
and franchising the Sargablock recipe to other businesses.
Elsewhere in Mexico, other entrepreneurs are experimenting
with new ways to use sargassum,
like making notebooks and even shoes.
A British startup called Seaweed Generation
is using sargassum to capture carbon
and store it at the bottom of the ocean.
Back in Mexico, Omar is simply grateful
to be living in his home country,
surrounded by the people he loves.
And after work, he returns to a home he built himself
using his own bricks.
Omar hopes his success will inspire others.