SAN DIEGO -- The minute the sun comes out after a rainstorm San Diegans run on the beach, buckle in their rollerblades or hop on a bicycle.

However, one thing most people know not to do is go into the water.

"Don't go in the water because of the pollution and the runoff," said one local bicyclist.

A local woman said, "We've always been told never go into the ocean after a heavy rain."

But researchers at the University of California, San Diego said contact with water is not the only concern.

"We need to not only worry about going into the water but also what we're breathing in during these types of storms," said UCSD graduate student Cassandra Gaston.

Pollutants tend to float towards the top of the ocean during a storm, researchers said. When winds are high and waves crash, it creates a sea spray that people inhale. Researchers said this sea spray could contain a number of pollutants.

"There is a potential that this is impacting people's lungs who are right next to the ocean or if you're going on a walk on the beach or going running or something," UCSD graduate student Andy Ault said.

"A lot of this runoff can be rich in pollutants, similar to some of the things that come out of a car or pesticides," said Gaston.

Some UCSD grad students are trying to figure out just how harmful these pollutants area. They are also taking rain samples from around the country to see how air pollution affects rain levels.

"These particles that we're analyzing can be in the rain droplet. For instance, if you're opening your mouth and you can take in some rain you're not just consuming water, you're consuming particles in the air," said UCSD graduate student Jessie Creamean.

Researchers said right now the health effects are still unknown.

Some beachgoers said they might just have to stay indoors for a few days after it rains.

"We might have to go to the gym after it rains," said one local resident.

Researchers said it is safe to be around the water a few days after a significant rainstorm.