Infantile lead poisoning from an Asian tongue powder: A case report & subsequent public health inquiry

Abstract

Introduction. Lead poisoning from novel environmental sources continues to present a challenge to clinicians who treat infants and children. Case report. A 12 month old infant of Thai parents was found during well child care to have a venous blood lead concentration of 61 mcg/dL. He was hospitalized for parenteral chelation with CaNa2EDTA and subsequently managed as an outpatient with oral succimer, with a reduction in blood lead concentration to 23 mcg/dL. Chronic lead poisoning was attributed to the use of a Thai tongue powder by the parents for the first seven months of the infant's life. This ethnic remedy was applied to the tongue to absorb toxins, reduce white patches present after milk feedings, and preserve the infant's health. Investigations. Lead contaminated the powder at 109,000 ppm as measured by x-ray fluorescence spectrometry. Two poison centers in Thailand were contacted and initiated a public health inquiry with the Thai Food & Drug Administration (Thai FDA) to remove contaminated products from the marketplace. Their investigation found six additional contaminated tongue powders (of 10 tested) in a Bangkok shop offering Chinese remedies, some with lead levels > 9000 ppm. These products, unregistered with the Thai FDA, were confiscated and the shop closed. Local media attention and case-finding activities of health officials identified one additional infant suffering from lead poisoning due to tongue powders. Conclusions. Asian tongue powders can be a source of lead poisoning. Medical toxicologists, poison centers, and public health agencies can work together internationally to accomplish effective post-marketing product surveillance.

Keywords:

• Herbs
• Lead poisoning
• Poison control centers
• Pediatric
• Dietary supplement

Acknowledgments

We wish to acknowledge the assistance of Drs. Surajit Suntorntham and Winai Wananukul and the staffs of the Siriraj Poison Control Center, Bangkok, Thailand and the Ramathibodi Poison Center for their assistance in this case. Dr. Nora Conlon of the Environmental Protection Agency Laboratory (Region 1), Chelmsford, Massachusetts, reported the laboratory analyses of the contaminated products. The Region 1 New England Pediatric Environmental Health Subspecialty Unit (New England PEHSU) is funded in part by a grant from the Superfund Reconciliation Act administered by the Agency for Toxic Substances & Disease Registry (ATSDR).