PORTLAND, Ore. -- We've heard about lead in schools, in water and in paint.

But a lead poisoning expert says lead in your home is the biggest risk to you and your family.

Perry Cabot's job is to investigate lead in homes. He's in charge of Multnomah County's Lead Poisoning Prevention Program. He says the place he finds the most lead is in old paint.

"Lead-based paint is the number one problem as far as lead exposure in our country for children today," he said.

Full coverage: Lead in Portland, metro schools

But he admits lead can also be in a home's drinking water, and it's really not the older homes that are most at-risk.

"The majority of lead in water test results come from houses built between 1970 and 1985," he said.

Homes built during that time often have copper piping with lead-based solder.

Cabot recommends all homeowners check their water lines. If they are copper, homeowners can use a do-it-yourself lead test kit to see if there is any lead present. And if you have any older brass fixtures, there's a good chance they contain lead.

"Up until quite recently, just within the last few years, lead was present in brass up to 8 percent," said Cabot.

Cabot says Multnomah County, which typically gets no more than a hundred requests a week for the home water test kits, is now getting overwhelmed.

"probably somewhere between 2000 in the last week," Cabot said.

Click here to request a water test kit from Multnomah County.