HOUSTON — Health departments around the country say traditional medicines used by many immigrants from Latin America, India, and other parts of Asia are the second most common source of lead poisoning in America — surpassed only by lead paint — and may account for tens of thousands of such cases among children each year.

The dangerous medicines are manufactured outside America and sold in America by folk healers known as curanderas and in ethnic grocery stores and neighborhood shops that offer herbs and charms. They are usually brought into the country by travelers in their suitcases, thereby slipping past government regulators.

“No one’s testing these medications,” an assistant professor of environmental health at the Harvard School of Public Health who researched the problem, Dr. Stefanos Kales, said. “There’s no guarantee it doesn’t have dangerous levels of lead.”

Lead is added to many of the concoctions because of its supposed curative properties, even though doctors say it has no proven medical benefits. In other cases, powders, and pills become contaminated with lead from soil or through the manufacturing process.

In Texas, California, and Arizona, lead poisoning has been traced to Mexican remedies such as greta, azarcon, and rueda — powders that are given to treat constipation in children and contain as much as 90% lead.

In New York City and Rhode Island, high lead levels in the blood have been tied to litargirio, a powder used by Dominican immigrants for such ills as foot fungus and body odor.

Dangerous amounts of lead have also been found in ayurvedic medicines, which are used in India and commonly found in South Asian immigrant communities in New York, Chicago, and Houston.

These medicines include ghasard, a brown powder given to relieve constipation in babies, and mahayogaraj gugullu, for high blood pressure.

Traditional medicines may account for up to 30% of all childhood lead poisoning cases in America, according to the Centers for Disease Control and Prevention.