When consumers plunk down cash for herbal supplements, they need to know they're getting what they pay for. But it could be a crapshoot when buying store brands of popular supplements sold by four major retailers.

Four out of five supplements, such as Ginkgo biloba and Saint-John's-wort, didn't contain the herbs claimed on the labels at Walmart, GNC, Target and Walgreens, according to tests commissioned recently by New York State Attorney General Eric T. Schneiderman. He claims the tests often found contaminants and cheap fillers such as rice, beans, pine and wheat.

That revelation is evidence of a dangerous lack of federal regulation.

Mislabeling and contamination are not just illegal. They endanger people with food allergies or those taking medications that could interact badly with unidentified substances sold as supplements.

Schneiderman's investigation and his demand that retailers immediately pull the products from store shelves are important services to consumers. The retailers are complying, although a few say they stand behind the quality of the products. The Council for Responsible Nutrition, a trade association of manufacturers, said Schneiderman's investigation was "a self-serving publicity stunt under the guise of protecting public health" and that his testing was wrong.

The industry's defense only highlights the argument that regulation shouldn't fall to a state attorney general.

Congress has failed to empower the Food and Drug Administration to demand that supplements are safe and labeled accurately. Companies are required to ensure that safety and accuracy, but no one checks. Unlike drugs, the supplements are not subject to FDA review for safety and effectiveness before they can be sold. And because Congress relaxed the law in 1994, supplements are subject to less stringent regulation than food.

The honor system has failed. What's needed is oversight.