PORTLAND, Ore. (KOIN) — Above average hexavalent chromium levels were found in Southeast Portland after the Department of Environment Quality monitored air data for 50 days.

DEQ inspectors were visiting sites of potential sources to pinpoint the cause, they announced Friday.

“In the case of hexavalent chromium, that’s not something that’s found in nature and so that’s something we look at a bit differently and in this case, with those being above our health targets, it’s something that we’re on,” said Brian Boling, DEQ laboratory program manager. “We’re doing additional monitoring, we’re looking at potential other sources in the area and continue to look at the picture to understand what’s going on.”

Boling says during the time the elevated levels were noticed, Bullseye Glass was not using chromium in glass production. They’re looking at other potential sources in the area, including a cement supplier, a metal finishing business and a nearby rail yard.

The metals do not pose any immediate health concerns but officials say that the levels “demand continued scrutiny.” The target concentration for hexavalent chromium is .08 nanograms per cubic meter of air, but the DEQ’s readings ranged from .086 to .26 nanograms per cubic meter across the four locations where the air was tested.

“As we learn information we may move monitors a bit; We may deploy additional monitors because you have facilities that are tight in location it’s very hard to pinpoint this and there’s different sources of hexavalent chromium,” said Boling.

Officials also noted that they had found elevated levels of selenium, but identified the source as Bullseye Glass. They said selenium does not pose a health risk.

The toxic air issue began in February when high levels of cadmium and arsenic were found in the air in Southeast Portland, near Bullseye Glass. In North Portland, high levels of toxics were found near Uroboros Glass.

The DEQ and the Oregon Health Authority say that toxic air data continues to show that there are low health risks for Portland residents.