A newly designed membrane uses thin amyloid protein fibers to pull heavy metals and radioactive wastes out of water. Clean up crew Amyloid-carbon membranes filtered over 99.9 percent of lead pollutants out of a contaminated solution, bringing the overall concentration of pollutant particles below a measurable threshold of 0.02 parts per million — and turning a once-grimy liquid clear (right). When paired with strong, porous carbon in a membrane, the lab-made amyloids successfully filtered over 99 percent of toxic materials out of solutions that mimicked severely polluted waters, the scientists report.