Prior to being banned as a paint additive in 1978, lead was manufactured into paint for four primary reasons: pigmentation, durability, corrosion resistance, and as a mold inhibitor. Lead can also be found in primers, stains, varnishes, and shellacs.

What is a Hazard?

Not all lead-based paint is classified as a hazard.

Lead-based paint is defined as paint or other surface coating that contains lead at or above the Federal limit of 1.0 mg per square centimeter or greater than .5% by weight.

A lead-based paint hazard is any condition that causes exposure to lead from:

1. Deteriorated lead-based paint.

2. Lead-based paint that is present on chewable, impact, or friction surfaces (such as window sills, door casings, and window sashes).
3. Lead contaminated dust.
4. Lead contaminated soil.

Lead-based paint in good condition (not peeling or cracking) on a wall may not be considered a hazard unless disturbed or deteriorated in the future. Typically, lead-based paint on a friction or impact surface (such as a window or door frame) is considered a hazard regardless of the current condition, due to the dust and chips generated by everyday use.

Locating Lead-Based Paint

Home tests for lead-based paint are not considered reliable by the Federal Consumer Products Safety Commission. In a CPSC evaluation of 104 tests in 2007, more than half came back with false negatives (indicating no lead when there was actually lead in the paint).

The most reliable means of testing is the X-Ray Frequency, or XRF, test. This is a hand-held device that is able to measure the presence of lead by bouncing low-level radiation off the surface. These machines are not available for home use and must be handled by a qualified professional. A professional lead hazard risk assessment costs about $200 to $300 and will identify all lead-based paint hazards in and outside a structure.

Professional testing facilities can determine the presence of lead in a sample using mass spectrometers and chemical tests.

Of the homes built prior to 1950, nearly all (98%) contain lead-based paint. Homes built prior to 1960 represent a higher risk due to higher lead content in the paint. However, because lead paint additives were not banned until 1978, the Iowa Department of Public health recommends that in the absence of a lead hazard risk assessment conducted by a qualified professional, homeowners and contractors should ASSUME that all paint in homes built prior to 1978 contains lead. This is the safest approach to home maintenance and renovation.

In fact, a home's age and condition are the best indicators of the presence of lead-based paint hazards.