What health-based guidance values have been set by regulatory agencies for thallium, other than the USEPA reference dose for drinking water (2 micrograms/litre)?

The US drinking water quality standards stipulate the content of thallium: thallium is an inorganic pollutant, with a maximum allowable contamination level of 0.002 milligrams per liter in tap water, while the public health target is 0.0005 milligrams per liter. If the maximum allowable contamination level is exceeded, it will cause hair loss, changes in blood composition, and affect health problems such as kidneys, intestines, or liver. Thallium, as a pollutant in water, commonly comes from leakage from ore processing stations and emissions from electronics, glass, and pharmaceutical factories.

The United States Permissible Exposure Limit (PEL), the ACGIH Threshold Limit Value and the California OSHA PEL are all 0.1 mg/m3 as an 8 hour Time Weighted Average.