After Flint, many were left wondering: how common are high lead levels in water systems in the United States? A USA Today report found that there were excessive levels in almost 2,000 water systems. The excessive lead levels weren’t limited to a particular region, and were found in all 50 states.

Around 350 of the water systems with recent failed lead tests provide water to schools and daycares—a particularly disturbing fact because of lead’s significant negative impacts on children. These impacts can include lower IQ, behavior problems, and attention disorders, and these effects follow children into adulthood.

The two states with the largest number of exceedances were Texas and Pennsylvania, which both had over 145. West Virginia was in the lowest group, with 19.

Check out the full map with the data here.

Many homes built before 1986 used lead pipes. If lead gets into the water, it is typically at this later stage: when water enters the home. If the water is not treated to prevent it, lead from these pipes can seep into the water, and can reach dangerous levels.

USA Today reported that 180 of the water systems with the high lead levels failed to notify their customers.