A trial thirteen years in the making, involving ten California cities and five companies that at one point sold lead-based paint, began this week. The cities are suing these paint-producing companies and parent companies, suggesting that the organizations knowingly endangered the health of children and families by allowing dangerous lead-based paint to be sold and plastered on walls around California.

 Lead paint was banned in the United States in 1978 due to health concerns. However, it still exists on the walls of millions of homes in California. While Antonio Dias, council for the representative of defendant corporation Sherwin-Williams, stated that lead-based paint is harmless if left intact, expert testimony given at the trial on Wednesday showed lead-based paint to be the main cause of lead exposure in children. Children may inhale paint dust from opening windows or ingest paint chips from the peeling walls of older homes in which the toxic agent was used.

The lawsuit is built around the claim that removal of lead-based paint from homes poses a “public nuisance.” Bonnie J. Campbell, a representative for the defendants, scoffed that this suggestion, stating that the claim has “no factual or legal merit.” Continued Dias, “it’s surprising that these counties would treat their own homeowners of well-maintained homes like owners of a crack house.”

Exposure to lead can cause death in high doses, and brain swelling, kidney damage, and anemia in lower doses. In children, the impacts are even more devastating, including impairing cognitive function, stunted growth, delayed puberty, and intellectual learning and behavioral disabilities.