Jackson, Miss. ? A federal jury ruled Friday against five families who claimed their children’s mental disabilities were caused by lead paint peeling from in their decades-old apartments.

Attorneys for Dallas-based paint manufacturer NL Industries Inc. had argued the 13 Mississippi children’s problems were caused by genetics or other sources.

Evidence presented during the three-week trial showed the children could have been exposed to lead from other sources, said Mike Jones, an attorney for NL Industries.

He said soil samples near the apartments also contained lead from automotive materials, such as car batteries.

The genetics defense struck a sensitive chord in the Mississippi Delta, where the apartments are and most of the residents are black and poor, including the plaintiffs.

In February, NL Industries and two other former makers of lead paint lost a lawsuit brought by the state of Rhode Island, which claimed the companies created a public nuisance that continues to poison children.