An Alaska businessman who acknowledged spreading a pesticide on a public right of way used by homeless people has been convicted of reckless endangerment and polluting.

Ron Alleva, 67, president of Grubstake Auction Co. in Anchorage, also was convicted Tuesday of unauthorized pesticide distribution and misuse of a pesticide, state prosecutors said.

Alleva formerly owned property across the street from a homeless shelter, the Brother Francis Shelter, and a soup kitchen, Bean's Cafe. The pesticide was strewn less than a block away.

Alleva has been a high-profile critic of the Anchorage's homeless policy. He said people attracted by the shelter and soup kitchen used drugs, defaced his property and stole from him, according to news reports.

Anchorage police and state environmental officials investigated on June 7 when a white substance was found where homeless people gather around the corner from the shelter.

Assistant attorney general Carole Holley, who prosecuted the case, said volunteers that day had picked up trash in the right of way. Grubstake Auction Co. employees assisted and then were recorded on video spreading the white substance, Holley said.

Investigators determined the powder was Zappit 73, a product advertised as a pool cleaner.

The powder is a registered pesticide and designated as hazardous by the Environmental Protection Agency. Exposure puts people at risk of serious physical injury, including blindness, Holley said.

"It's really strong stuff," she said.

Homeless people could have been especially vulnerable if they did not have the opportunity to bathe or suffered from mental illness, Holley said.

"It could be that people become sick, and they don't know what caused it," she said.

Holley argued to the jury that Alleva acted out of hostility toward the homeless, she said.

Immediately after the chemical was spread, Alleva told the Anchorage Daily News that he considered it a disinfectant. He described his action as a public service meant to mitigate a public hazard of human feces, vomit and old food that people had left.

The city fire department's hazardous material team removed 1,400 pounds (635 kilograms) of contaminated soil from the site.

Alleva and his attorney, Paul Nangle, did not immediately return messages requesting comment.

Grubstake Auction was convicted of the same counts as Alleva. Alleva and the company will be sentenced May 21.

Alleva faces a maximum of a year in jail and a $25,000 fine on each misdemeanor count, Holley said. The company faces fines of up to $500,000 on each count. The three environmental misdemeanors could be consolidated for sentencing, Holley said.