When Andrew Miller works on his Mount Airy home, his training as a certified lead-dust sampling technician comes in very handy.
"I put drop cloths down everywhere, have HEPA [high-efficiency particulate air] filters on all the vacuum cleaners, and wet wipe every surface to make sure I have picked up all of the dust," said Miller, owner of Ally Services, an environmental building and contracting services firm.
Such precautions are necessary. In Philadelphia alone, the Census Bureau's 2009 American Housing Survey showed, 91.6 percent of residences were built before 1978, the year that lead in paint was outlawed.
Events in Flint, Mich., have raised fears about dangerous lead concentrations in drinking water. But the Centers for Disease Control and Prevention says the most hazardous sources of exposure for children are deteriorating lead-based paint and lead dust, on surfaces and in the air, inhaled or transferred from hand to mouth.
Miller's business is part of an industry that tests homes and apartment buildings for lead, then determines the best way of dealing with it. Since Flint's troubles hit the news, there has been a "300 percent increase" in lead-related telephone inquiries to his office, he said.
How can you know whether you and your children are exposed to lead where you live?
A blood test can determine lead levels in the body. As for the home, both the U.S. Department of Housing and Urban Development and the Environmental Protection Agency recommend that anyone with a residence built before 1978 just assume that lead paint is present and take special precautions during even minor repairs.
In Pennsylvania, 3.9 million, or about 70 percent, of the state's 5.8 million housing units were built before 1978, according to the Census Bureau's 2010 American Community Survey. The New Jersey Department of Community Affairs puts the number at more than 2.4 million of that state's 3.3 million housing units.
About 24 million U.S. housing units are considered to contain deteriorated lead paint or elevated levels of lead-contaminated dust, with more than 4 million of those dwellings home to one or more children.
Of particular concern are children under age 6, the CDC says, because they tend to put their hands or other objects that may be contaminated with lead dust into their mouths. Youngsters are especially vulnerable because their rapidly developing brains and nervous systems are particularly sensitive to the effects of lead, the American Academy of Child and Adolescent Psychology says. Reduced IQ, learning disabilities, and behavior problems can result.
The World Health Organization says lead also causes long-term harm in adults, including increased risk of high blood pressure and kidney damage. Exposure of pregnant women to high levels of lead can cause miscarriage, stillbirth, premature birth and low birth weight, and minor malformations.
Because of the hazard it poses, reducing or removing lead in a home - such as by replacing windows whose lead-based paint has deteriorated - is a job for EPA-certified professionals only, who must meet training standards and comply with safe work practices.
Windowsills and window wells are common sources of lead exposure. Lead dust is stirred up "when windows are being raised and lowered as the weather gets warmer," Miller said.
Both HUD and EPA have established standards and protocols for the identification and removal of lead-based paint. Companies that violate the work practice, training, or administrative rules could face fines of up to $37,500 a day, the EPA says.
Pennsylvania and New Jersey have incorporated those regulations into their statutes and provide lists of licensed certified testers and contractors who have met federal and state requirements.
There are four major methods of dealing with residential lead-paint hazards, the EPA says:
Replacement, which involves removing a building part containing lead-based paint and substituting a new one.
Enclosure, which covers the lead-based paint with a solid barrier, such as drywall.
Encapsulation, in which the surface containing lead-based paint is coated so that it is not accessible.
Removal of the paint, the most expensive of the four.
The cost of a typical lead-paint remediation ranges from $8,000 to $12,000, said Shantae M. Goodloe, a HUD spokeswoman in Washington.
Even routine home-improvement efforts have the potential to increase lead exposure, however.
"Common renovation activities like sanding, cutting, and demolition can create hazardous lead dust and chips," the EPA says in its brochure "The Lead-Safe Certified Guide to Renovate Right" (https://goo.gl/LB4TLh). "The key to protecting yourself and your family during a renovation, repair or painting job is to use lead-safe work practices such as containing dust inside the work area, using dust-minimizing work methods, and conducting a careful cleanup," the brochure says.
Although the housing industry and the scientific community agree that lead paint is a health hazard, both sides have been vociferous critics of the EPA's regulations to tackle it.
Scientists, including members of the EPA's own scientific advisory board, have taken issue especially with safe-level standards for lead particles in house dust and yards, which haven't changed since 2001, said David E. Jacobs, chief scientist at the National Center for Healthy Homes in Washington.
"They need to be revised based on our new knowledge," Jacobs, an advisory board member, said Wednesday, noting that while the regulations have helped reduce blood-lead levels in 90 percent of the population, "there are still 530,000 children every year" whose tests exceed acceptable levels, "and that is too many."
For its part, the housing industry, with the support of members of Congress, has sought repeatedly to soften EPA regulations.
In 2014 and 2015, legislation was introduced to restore a rule giving homeowners the right to opt out of the EPA's lead renovation, repair, and painting provisions if they would attest that there were no children or elderly living on the premises. According to the Congressional Record, the measure, which died in committee, sought to require the EPA to approve a test kit that met its own standards for avoiding false positives.
Jay Cipriani, of Cipriani Builders in Woodbury, who remodels many homes constructed before 1978, said, "We test them to a T. We test the trim, doors, walls, and ceiling for lead in the areas we will be working in. If we find lead, we follow strict guidelines as to how to control dust.
"It may add about $300 to $500 to the cost of an average job, as we need to buy and set up a lot of lead-dust protection, disposable plastic tarps," Cipriani added.
Since December 2012, Philadelphia has required property owners who rent to families with children under age 6 to certify that those properties have been tested for lead paint. If evidence of lead-paint contamination is found, it must be remediated.
Elevated lead levels are found in about 1,000 Philadelphia children a year, or 3 percent of those tested, local health officials said in hearings when the bill was introduced in City Council.
When contamination is identified in homes with infants, however, some families are unwilling to allow remediation, even when it is free, the 2011 Philadelphia Lead-Free Homes Study, headed by Cara Campbell of Drexel University's School of Public Health, found.
In 1995, a federal law went into effect requiring every home seller and landlord to disclose the presence of "any known lead-based hazards" in residences built before 1978. Jacobs, of the National Center for Healthy Homes, said the original version of that law would have required an inspection, "instead of simply checking the 'I don't know' box."
The EPA distinguishes between inspecting a home, which is a surface-by-surface investigation to determine whether there is lead-based paint and its location, and doing a risk assessment, which determines the presence, type, severity, and location of lead-based paint hazards, and ways to control them.
"To my knowledge, I've never heard of a [home-sale] deal that went bad because of the presence of lead paint," said Harris Gross, president of Engineers for Home Inspection in Cherry Hill, "although people with children are understandably more cautious about it, I've found."