By Maria Medina

SUTTER COUNTY (CBS13) — Nearly a dozen construction workers were sprayed with pesticide from a helicopter in Sutter County, sending some of them to the hospital with chemical pneumonia.

Farms in the area are sprayed with pesticide all the time, but this time, investigators say the pilot failed to do his job.

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The Jones Aviation pilot was flying a helicopter when he accidentally sprayed 10 workers on the ground.

“They smelled the product and then they felt some drift on them,” Sutter County Agricultural Commissioner Mark Quisenberry said.

The crew was working on a levee when they were sprayed. They say they quickly began experiencing headaches, skin irritation and shortness of breath.

“Through the correct procedures they went to the hospital to be examined,” he said.

According to the county’s investigation, the workers went to the nearest urgent care facility in Yuba City where doctors told them to remove their clothing, decontaminate with water and have blood drawn for testing.

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They all went home that day, but they would be in and out of the hospital for weeks. Some came down with chemical pneumonia, and at least one man was told to stay off work for two weeks.

“This is the first one in 10 years, so they’re very, very rare,” Quisenberry said.

The owner of Jones Aviation told CBS13 over the phone that his pilot was an apprentice who had flown for a couple of years. Most of the time they would have spotters on the ground, but on that July day, they didn’t.

The chemical sprayed on the workers, govern 4e, is used to kill a bug that feeds on walnut trees. It’s not something that people should come in contact with.

“When any persons exposed to a pesticide that means it makes top level investigation on what happened and what transpired,” Quisenberry said.

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The owner expects to be fined. The commissioner says he could take it to the district attorney, which would mean a stiffer penalty.