Breaking a CFL could potentially release mercury into the immediate environment (government websites suggest to replace one square meter of carpet where the breakage occurred).
Breaking an LED light requires more or less the same cleanup as breaking the traditional lightbulb or maybe some plastic shards but no toxic material is released into the environment unless the components are crushed into a powder and inhaled.
Led Light in manufacturing use mostly the same chemicals any plastics plant would use, the chips themselves mostly consist of nano crystals of elements found in the earth that are non-toxic.
