doubts and uncertainties about dangerous pfas perfluoroalkyl and polyfluoroalkyl substances

about asking attention cancer carcinogen carcinogenic chemical chemicals chemistry compounds concept concepts confusion contamination damage danger dangerous doubt doubts enhanced environment environmental fluorinated fluorine fluorochemicals health illness impermeable interrogation issues mark microbiology organic organofluorine perfluoroalkyl pfas pfass pfoa pfos pollutant pollutants pollution polyfluoroalkyl properties question rainproof repellent risk substances synthetic their toxic uncertainties uncertainty used warning water water- water-resistant waterproof waterresistant