WASHINGTON - Home improvement giant Lowe's Companies Inc. has agreed to pay $500,000 after federal investigators found its home renovation contractors in nine states had violated safety standards for lead paint. The retail chain was also unable to provide documentation proving some contractors employed by the company were certified to work with the toxic substance, the Environmental Protection Agency and Justice Department said today.

The investigation by the EPA stemmed from tips and complaints from homeowners who had used Lowe's renovation contractors. In reviews of company records the government found contractors had not used EPA-approved lead-test kits on projects, or lacked proper training to work with the hazardous element known to cause developmental problems in children and kidney and cardiovascular illness in adults.

The EPA also found contractors had failed to properly clean and contain work areas in three homes, although the agency emphasized they had not found any direct cases of bodily harm in the course of their investigation. The punishment sought against Lowe's was more cautionary, they said. Officials also stated the violations were not company-wide, but isolated to certain brick-and-mortar stores discovered in their investigation.

"This is not to send an alarm signal that people who have had work repairs done should be alarmed about this," Acting Assistant Attorney General Robert Dreher said in a conference call with reporters today.

EPA Assistant Administrator Cynthia Giles said it sent a clear message to companies to comply with the toxic materials standard.

"Lowe's is taking responsibility for the actions of the firms it hires, and EPA expects other contractors to do the same," she said.

The officials pointed homeowners to the EPA website for fact sheets on protective measures and red flags to watch out for when working with lead-based materials.

Lowe's says they have always sought to comply with the EPA's Lead-Based Paint Renovation, Repair and Painting Rule standards since they were enacted in 2008, and have "resolved all issues alleged by the EPA."

"Lowe's hires thousands of independent, third-party contractors and the EPA identified only a few who failed to meet certain record keeping or work practice requirements regarding lead-based paint," a Lowe's spokesperson told ABC News. "There have never been any reports of lead-based paint health issues associated with any projects completed by Lowe's contractors."

Lowes declined to provide an estimate on the total number of homes that may have had renovations performed by the violating contractors, or whether the company had sought disciplinary action against them.

The EPA discovered the infractions through review of Lowe's stores in Alton, Ill.; Kent and Trotwood, Ohio; Bedford, N.H.; Southington, Conn.; South Burlington, Vt.; Rochester, N.Y.; Savannah and Lebanon, Tenn.; Boise, Idaho Falls and Nampa, Idaho; and Muldoon, Alaska.

Today's settlement also mandates the home improvement chain create a new compliance and training program at its more than 1,700 stores in the US.