Recent activity in a pair of long-simmering lawsuits has shined a fresh light on the challenges organisations face in compelling the US EPA to act on chemicals of concern through TSCA ‘citizen petitions’.

Public health advocates this week asked a federal court in California for a second trial over their petition calling on the EPA to issue a TSCA rule limiting fluoride in drinking water.

The filing comes more than two years after the original trial concluded without a ruling and the judge urging the parties to try to reach a resolution on their own in light of new research on the health effects of fluoride.