Vermont Public Radio says traces of lead have been found in the ink used in the designs of 11 different series of mugs.
The mugs were issued between 2002 and 2011.
VPR says it believes all the mugs in question were manufactured within applicable federal standards.
The station says its vendors have also assured VPR that the items comply with the appropriate FDA and federal consumer protection regulations.
However, the tests have raised questions about whether a state law protecting children from lead exposure is applicable to the VPR mugs.
The Vermont Lead in Consumer Products law sets limits on lead in products marketed to children and those they might come into contact with.
The Vermont Attorney General’s Office is looking into whether the mugs fall under that law.
VPR announced late Friday that tests on a 2011 mug indicated lead content in the ink used in the design on the outside of the mug.
The test was conducted after a listener reported having a mug from the same 2011 series checked by the Vermont Department of Health.
The state uses a scanner known as an X-ray Fluorescence Analyzer to test for lead content.
The health department says the test showed no lead present on the inside of the mug.
But the results indicated lead, apparently contained in the ink used in the design on the outside of the mug, at a level of 3.18 percent, exceeding the .01 percent limit for exposure to children set by state law.
VPR President Robin Turnau says the station will provide the Attorney General’s office with any information it has collected.
Turnau says VPR is currently having more mugs tested by an independent firm in order to resolve any concerns about safety.