The warning is added to comply with California’s Prop. 65 that requires warnings even when certain chemicals are or may be present at extremely low levels, well below any level that may cause harm.
California’s Prop. 65 does not require and we cannot provide any further information along the lines you request. One reason for this is the chemicals on the Prop 65 list change with some frequency and the chemicals, concentration of the chemicals in the parts or the parts themselves may also change from time to time.
We encourage you to learn more about California’s Prop 65 by visiting either oag.ca.gov/prop65 or oehha.ca.gov/proposition-65.