Federal regulations limit exposure of chrome-plating workers to 50 micrograms--or 50,000 nanograms--per cubic meter over an eight-hour period.
Health and air quality officials briefed school administrators and teachers on the potential health problem in January while air monitoring continued. Concerns grew the following month when two teachers miscarried severely deformed fetuses.
For the Record
Los Angeles Times Sunday May 1, 1988 Home Edition Long Beach Part 9 Page 4 Column 1 Zones Desk 5 inches; 176 words Type of Material: Correction
The Times reported last Sunday in its Southeast/Long Beach editions that a maximum of 13 nanograms of hexavalent chromium, a carcinogen, had been detected during a six-hour period in the air at Suva elementary and intermediate schools in Bell Gardens.
Air tests conducted earlier this year by the South Coast Air Quality Management District actually detected a maximum of 430 nanograms of the toxic metal in the air on school grounds during a six-hour period. An AQMD report on the findings contained a typographical error, AQMD spokesman Bill Kelly said last week. A nanogram is one-billionth of a gram.
An AQMD spokesman also erroneously told The Times that if the average concentration of hexavalent chromium at the schools were breathed 24 hours a day, every day for 70 years, it would produce an estimated 37 to 450 additional cancer cases per 1 million people. Instead, those figures were weighted to reflect part-time, or anticipated, daily exposure by students and workers at the schools over 70 years.
Hexavalent chromium, a byproduct of chrome plating, is emitted by two chrome-plating factories adjacent to the schools. Hexavalent chromium is known to cause cancer in humans. It also has caused miscarriages and birth defects in laboratory animals.
A third teacher had terminated her pregnancy last September when she found out the fetus she was carrying was deformed. A staff survey turned up six other miscarriages since April, 1987, Swanson said. It was not immediately known how many of those miscarriages involved deformed fetuses. Six other teachers are pregnant and expect to give birth this summer, she said.
The county health department is studying the miscarriages and deformities to determine if they are related to the hexavalent chromium emissions, Papanek said. The county also has helped the staffs of the schools to prepare the community survey.
Papanek said his office has received reports from school officials and residents of several birth defects in children in the area surrounding the plants.
"There's the allegation that there are a lot of birth defects out there," Papanek said. "We want to get those cases verified."
The California Air Resources Board in January, 1986, designated hexavalent chromium a toxic air contaminant that warranted strict control. State and local air pollution authorities are gearing up to sharply reduce the amount of the metal that is released into the air.
Because of industry, hexavalent chromium is present in minute amounts in the air throughout the Los Angeles Basin. Background levels of the heavy metal in the Los Angeles area range in concentration from just over 3 nanograms to 11 nanograms per cubic meter of air, according to an AQMD report.
Emissions of hexavalent chromium from most sources in the Los Angeles Basin have been controlled as part of a general category of pollutants called particulates. Particulates also include dust and other relatively innocuous pollutants, officials said.
Neither chromium plant is exceeding its particulate limit, Davidson said.
In February, the California Air Resources Board adopted a model rule to stringently control hexavalent chromium as a separate and highly toxic pollutant. Under the rule, industry eventually will be required to remove 95% to 99.8% of the heavy metal from its emissions.
State law requires local agencies to adopt an equal or more stringent rule by August 18. The board of the AQMD will consider passage of a local rule--identical to the state model--at its May 6 meeting.
J & S Chrome would meet the more stringent standards with its current pollution control equipment, Davidson said. Nevertheless, the AQMD wants the taller exhaust stack to lessen the local effect of the emissions.
Chrome Crankshaft would not meet the new standards and it eventually will be required to install emission controls as well as a 50-foot stack.
Even though the local rule has not been approved, the AQMD may be able to compel the two plants to act based on a regulation that prohibits emissions that pose a danger to the public health, said Ed Camarena, the AQMD's deputy executive officer for operations.
"We are committed to bringing these levels down as quickly as possible," Camarena said. "We believe they're going to be cooperative. If they are not, we will vigorously pursue legal action to require the mitigation measures."