As part of a crackdown on pollutants blamed for causing much of the region's smog, air regulators and several local governments have sued Home Depot Inc. for selling illegal paints and other products.
Two related lawsuits filed Thursday allege that from 2007 to 2010, the nation's largest home improvement chain sold paints, wood lacquers and other coatings that contained excessive levels of smog-forming chemicals.
According to the lawsuits, the illegal products were sold at more than two dozen stores across Southern California, even after the company was notified that it was breaking local air regulation laws.
One complaint, filed by the South Coast Air Quality Management District, charges Home Depot with violating the California Health and Safety code. It calls for $30 million in civil penalties.
The other, filed by attorneys from Orange, Riverside and San Bernardino counties, as well as the city of Los Angeles, charges the company with unfair business practices and false advertising.
In a statement, an attorney for Home Depot said the chain cooperated with air quality regulators after it was notified of the code violations.
"We have fully cooperated and removed the products in question," the statement said. "We believe the government has a mistaken view of the facts, and we are fully prepared to defend our position."
The Los Angeles Basin, which has long been known for having poor air quality, is also known for having some of the nation's strictest regulations when it comes to air-polluting products.
The rule Home Depot is accused of violating was imposed in 1977. It limits the amount of volatile organic compounds, or VOCs, that are allowed in "architectural coatings," a category that includes paints, lacquers and other products.
VOCs are used in many household products, including aerosol sprays, cleansers and disinfectants. But they have been targeted by environmentalists because when they evaporate into the air, they react with other chemicals to form smog.
Each day in the Los Angeles Basin, more than 23 tons of VOCs are released into the air from architectural coatings, according to government regulators. That is more daily pollution than is typically produced at an oil refinery or power plant and more than is emitted by 1.5 million cars.
"People think they're just opening a can of paint, so what's the harm, what's the big deal?" said Nancy Feldman, a lawyer with the South Coast Air Quality Management District.
But the district takes such pollutants seriously, she said. In recent years, the agency has filed lawsuits against other big-box retailers that sell products that exceed accepted levels of VOCs.
Last year, the district won settlements totaling more than $3 million from Lowe's and Wal-Mart after it sued the stores for selling such products.
Throughout the state there has been a push by prosecutors to crack down on pollution by large corporate stores.
Last year Target Corp. agreed to pay $22.5 million to the state and several local governments to settle an investigation into the alleged dumping of hazardous waste.
In Los Angeles, this is not the first time city prosecutors have taken Home Depot to task for its environmental record.
In 2007, the company paid nearly $10 million in a settlement after the city sued it for improperly handling hazardous materials.