Sometimes Litharge and Massicot are used interchangeably but they are distinct, and the Natural Pigments site has information about their differences. Litharge and massicot are rarely used as a standalone pigments in oil and are more often used as driers. Litharge (also called the alpha form) tends to be more orange and Massicot (the beta form) is more yellow.
This substance is toxic. The Artist's Handbook highlights its toxicity and instability.
Monona Rossol's work has a section on health problems from lead pigments in the Artist's Guide to Health and Safety. Her most recent research can be found through her site. Lead is toxic.
