Le bonheur de vivre features a large amount of cadmium sulfide-based yellow. Portions of the painting containing cadmium sulfide are turning white or brown, degrading the work. University of Delaware Prof. Robert L. Opila, in collaboration with Barbara Buckley, head of conservation at the Barnes, and Jennifer Mass, a senior scientist and head of the Scientific Research and Analysis Laboratory at Winterthur, studied the paint’s material microstructure in an attempt to determine why the cadmium sulfide is changing color.[1][6]