A study looked at phosphorus levels in Pittsburgh streams before and after drinking water was treated with a chemical to prevent lead corrosion in pipes.
Many school are not addressing such hazards as poor indoor air quality, mold, radon and lead in their buildings, including in southwestern Pennsylvania.
More than 70% of homes in Pennsylvania are estimated to have been built before the 1978 lead paint ban, leaving many kids vulnerable to lead poisoning.
A 2021 study found that of 65 Pennsylvania school districts surveyed, 91% of water tests detected lead. There is no safe level of exposure to lead for children.