This is Scientific American's 60 Second Science.

I'm Christopher Intagata.

Residents of the southern US might be familiar with this dusty summer phenomenon.

We are breathing dust that at one time originated over Africa.

Dust particles are carried 15,000 feet into the atmosphere.

Another dust cloud from Africa's Sahara Desert has made it all the way to Houston.

The dust clouds surf on trade winds towards the Caribbean.

And since the dust is rich in minerals like iron, it's like an airborne delivery of fertilizer to marine life there.

So when you get this pulse of iron that comes, it's a micro nutrient, you know, a trace metal that's

needed by all of life that all of a sudden is available at least for a short amount of time.

Aaron Lipp, a microbiologist at the University of Georgia.

She and her team studied the phenomenon, sampling waters in Barbados and the Florida Keys.

And they found that these fertilizer dumps seem to encourage bacterial blooms, including

vibrio species, some of which can cause cholera or food poisoning.

Vibrio and probably other bacteria that are really capable of responding to sort of this

feast that's provided to them.

They just use it quite rapidly, so within that first 24 hours you see a very very big population spike of these bacteria.

A spike of 50 to 30 times their usual numbers.

The finding is in the proceedings of the National Academy of Sciences.

If all this makes you want to skip the oysters after a

sandstorm. So I would say that is a personal decision but but summer in general is

the riskiest time to eat oysters. For now she says there's really no evidence to link Sahara dust to your risk of a bum

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