Emerging Contaminant

An emerging contaminant is a substance recently recognized as an environmental concern, usually unregulated or only newly regulated, with limited toxicity and occurrence data. The class spans pharmaceuticals, personal-care products, PFAS, quaternary ammonium compounds, brominated and organophosphate flame retardants, microplastics, and artificial sweeteners. They reach the sea mainly through wastewater treatment effluent, which is not designed to remove them. Detection follows advances in analytical chemistry rather than new releases, so many are legacy chemicals only now measurable at nanogram-per-liter levels, prompting watch lists under the EU Water Framework Directive.