EAST CHICAGO | The volunteer environmental monitors who said they discovered unexpectedly high levels of hazardous chemicals in the air of the city's far north side last month pledged on Thursday to continue their vigilance.

Members from two local community organizations who performed the tests just outside BP's Whiting Refinery outlined their results and plans for the future at a news conference in Marktown, just steps from where they took samples on July 10.

"Good air and water are basic to quality of life," said Ruth Turpin, of the Coalition for a Clean Environment, which conducted the study and analyzed its own findings along with the Calumet Project for Industrial Jobs.

The groups' analysis of the air samples found two probable cancer-causing chemicals; two thought to harm brain, heart and liver functioning; one that may be damaging to the lungs; and nine other possibly toxic substances, the groups said.

Though the samples were taken near BP's fence line, several of the toxic chemicals aren't even used at the refinery, according to its official Toxic Release Inventory -- a listing of substances emitted from the site.

Monitoring air quality with the low-cost sampling units -- approved by the U.S. Environmental Protection Agency in 1996 -- will continue, said Bessie Dent, of the Calumet Project.

Anyone can help, she said, by being a "sniffer," keeping a log book of when and where they see or smell unusual events, and chronicling periods of exceptional eye or nose irritation.

These logs can be cross-referenced with data collected from the "bucket brigades" -- the air monitors so named after the 5-gallon buckets in which the collection apparatus is housed -- and point the brigades to other locations for air testing.

The north side area's City Council representative, Robert Garcia, D-5th, said he would seek council approval to discuss the air monitors' findings with BP and address concerns of the community.

Volunteers will be out collecting air samples again in the fall, Turpin said, or even sooner if odor complaints increase and as finances permit. She said her group is currently planning fundraising events to continue the testing.

Though the collection units cost about $125, the laboratory charges $200 to analyze each sample, Dent said.