On the heels of an environmental study that found lead-tainted water in public housing developments in Watts, Los Angeles Mayor Karen Bass has called on the city’s housing authority and largest water utility to conduct further testing for the potent neurotoxin.

The discovery of lead-contaminated tap water in Watts, home to three of Los Angeles’ 13 major public housing complexes, has jolted city leadership and raised serious questions about the age of the plumbing that serves low-income residents. Although California banned the installation of lead pipes in 1985, the average home in Watts is nearly 77 years old, which makes the South L.A. neighborhood more likely to contain corroded lead plumbing.

“It’s absolutely unacceptable for families to not have access to safe, clean drinking water,” Bass wrote on X.