Derby Street’s Arsenic Signs Are Principally Precautionary

By Richard Brenneman
Tuesday June 03, 2008 - 02:34:00 PM

The city has closed a lot on the 1400 block of Derby Street, across the street from a day care center, because of potentially dangerous levels of arsenic. 

Berkeley’s hazardous materials coordinator Nabil Al-Hadithy said that the contaminated soil poses little danger, but the fence was put up as a precaution. 

“We may have put up signs that are a bit overly worrisome,” Al-Hadithy said, referring to the sign on the fence that declares: “DO NOT ENTER—Unauthorized Entry Prohibited—Elevated Levels of Arsenic.” 

Neighbors who live near the old railroad line that slices through the Derby Street property had been worried about potential toxins in the now-fenced vacant property, so they worked with an city expert and tested six soil samples from the site. 

“The highest result was 140 parts per million,” well above the levels of metal naturally occurring in city soils, Al-Hadithy said. “The normal levels in city soils run from 2 to 3 parts per million to about 40 in the hills near the Lawrence Hall of Science.” 

While the amounts found on the abandoned rail line weren’t likely to cause problems with normal exposure, they could cause problems for youngsters with pica—the compulsion to eat dirt—still, he said, the safest course of action was to fence off the site and post the warning. 

As for the next step, “We’ve put in for funds to evaluate the site with the state toxicologist,” Al-Hadithy said, “so we can figure out how to use the site safely in the future. We believe that if we cover the site with clean soil and plants in above ground containers, there won’t be a risk. But we need an evaluation.” 

As for the soil of the metallic poison, “We believe it may have been applied as a pesticide” back in the days when trains steamed the neighborhood, he said. 

But until funds for the study are released so that a scientist from the state Office of Environmental Health Hazards Assessment can come up with a recommendation, the safest course of action is to fence off the site, he said. 

As for the future of the right of way, which runs for several blocks south of Sacramento Street, all ideas are on holding pending the outcome of the study. 

“Until such time as that happens, we are taking the precaution of keeping people out. That’s the precautionary principle,” he said, “and I like that. But there’s no reasons for parents to worry about their children who attending a day care center across the street.”