LARGO — A chat with a longtime Largo resident prompted City Manager Mac Craig to explore whether the City Hall property has high levels of arsenic. It apparently doesn't, according to a study of soil samples released last week.
"There's no arsenic issue on this site at all," Craig said.
Results of the study conducted by Tampa-based Seavy & Associates showed that arsenic levels from 12 soil samples were lower than the state's safety limit for cleanup at industrial or recreational properties.
One site by a patio near the back of City Hall tested at 2.58 parts per million, which is higher than the state's limit of 2.1 for residential areas. But officials say City Hall would not be classified that way.
"It's an acceptable concentration to have on our property," said Assistant City Manager Mike Staffopoulos.
Joshua Hamilton, a toxicologist who researches how arsenic and other toxic metals may increase the risk of human disease, said the concentrations reported were not of concern.
Arsenic is not absorbed through the skin, so arsenic in soil is not a major health worry for adults, said Hamilton, chief academic and scientific officer at the Marine Biological Laboratory, an international research center in Massachusetts.
Children are a different matter because they may ingest it through hand-to-mouth activities or by purposely eating dirt. Also, he said, concern with arsenic is not occasional exposure but chronic exposure over months at high doses, or exposure over years or decades at lower doses.
Soil guidelines set by government agencies are intentionally designed to be highly protective, and they're particularly stringent in Florida, said Christopher M. Teaf, a toxicologist at Florida State University.
Craig said he requested the arsenic study, which cost about $3,500, after a talk with Don Forehand, president of the Largo Area Historical Society.
The issue first drew Forehand's attention when the city began exploring arsenic levels at Largo Central Park's Nature Preserve, which is now closed.
A test in July 2008 found low levels of contaminated soil across the preserve site. And years earlier, a city study found elevated arsenic levels in several locations. The levels around the observation tower there were more than three times Florida's target level for cleanup of industrial areas.
Forehand wondered whether the problem at the nature preserve was linked to arsenic-laden pesticides, which may have been used decades ago at citrus groves around where City Hall now sits.
Forehand said he talked with someone at the city then, but they didn't take him seriously. He broached the subject again a few weeks ago, after the city started talking about the condition of the municipal building.
"I was concerned they may not have knowledge of the area," said Forehand, 73, who grew up in Largo.
Forehand met with Craig, and, among other things, he raised questions about the possibility of elevated arsenic levels on the City Hall property.
Forehand's father worked in the citrus groves from 1925 to 1950, and Forehand sometimes watched his dad as he sprayed the trees with an arsenic-based pesticide. He recalled how the heavy rains filled the lake nearby and washed across Bay Drive, then known as Roosevelt Boulevard.
Maybe, he thought, that's how some of the arsenic made its way to the preserve.
City officials say they don't really know the source of the arsenic at the preserve. But they've speculated about two possible culprits: pressure-treated wood used to build the observation tower or a landfill that existed in that area, near Highland Avenue and East Bay Drive, from the late 1960s until 1981.
The city is still analyzing the preserve, Craig said.
"We know there's some areas we're going to have to clean up," Craig said.
Lorri Helfand can be reached at email@example.com or (727) 445-4155.