Lead poisoning outbreak from consumption of contaminated Ayurvedic medication

To the Editor: In August 2020, the South Eastern Sydney Public Health Unit, located in New South Wales, Australia, received a statutory laboratory notification of an elevated blood lead level of 0.34 µmol/L in a preschool‐aged child recently diagnosed with autism. This was above the 0.24 µmol/L level requiring notification under the Public Health Act 2010 (NSW). The test had been requested by the child's paediatrician due to concern about the child’s recent consumption of an oral Ayurvedic medicine prescribed by a naturopath.

Our environmental health officers undertook a home lead assessment, during which a soil sample and the Ayurvedic medication sample were taken for heavy metals analysis. The soil lead concentration was 160 mg/kg. The medication was labelled Manasmithra Vatika (MV), manufactured in India (Box). Analysis revealed that it comprised 0.96% lead by weight. The naturopath indicated that they had prescribed the medication to other child and adult patients, some of whom were seeking treatment for autism. Most consultations were conducted online and the prescriptions were purchased online.

We were concerned about the risk of lead toxicity in the naturopath’s other patients who had been prescribed MV, and mounted a public health investigation in order to inform patients of their risk, to advise them to cease use of the medication, and to identify the extent of the problem.

The naturopath provided a list of 28 patients (13 children) to whom they had prescribed the medication. We directly followed up the 12 NSW patients (other than the index case), asking whether they had taken MV, and, if so, in what dosage and over what period. We advised those who were taking MV to immediately cease its use, and to seek blood lead level testing through their own doctors. We asked patients to provide us with any remaining MV for lead analysis.

Five patients provided MV samples; analysis showed lead content of 0.74–0.96% (mean, 0.81%) by weight. Four patients had an elevated blood lead level ranging from 0.30 to 0.68 µmol/L (reference interval, < 0.24 µmol/L). A fifth patient, whose blood lead level was undetectable (< 0.1 µmol/L) had ceased taking the MV at least 3 months before measurement.

Based on these findings, we initiated a multi‐agency investigation involving NSW and Australian government regulatory bodies. Action taken against the naturopath by the Australian Health Practitioner Regulation Agency and NSW Health Care Complaints Commission prohibited them from treating medical conditions, such as autism. The naturopath voluntarily ceased prescribing MV and immediately contacted their patients to inform them of the lead adulteration of the preparation.

The NSW distributor of the MV medication was investigated by the NSW Health Pharmaceutical Regulatory Unit and the Therapeutic Goods Administration, leading to the distributor ceasing to import the adulterated MV. The Therapeutic Goods Administration issued a public warning regarding the presence of lead in MV preparations generally, without naming an implicated brand or source.1

Lead exposure in children can be linked to reduced intelligence, and behavioural and developmental impacts.2,3 Ayurvedic medicines are formulated and prescribed based on ancient Indian texts. Although they are herbally based, Ayurevedic texts also provide for formulation with heavy metals including lead.4 Their use has been associated with elevated blood lead levels in patients.5 The public health investigation and subsequent multi‐agency intervention we have described prevented ongoing exposure of patients to a lead‐contaminated herbal product.

1. ▪ health practitioner awareness be raised regarding the risks of recommending or prescribing unregistered, imported medications;
2. ▪ clinicians consider testing for blood lead in patients who have consumed unregistered, imported Ayurvedic medications;
3. ▪ public health professionals be engaged in the investigation of patients with elevated blood lead levels in the absence of an occupational source;
4. ▪ community awareness be raised regarding the risk of consuming unregistered, imported Ayurvedic medications; and
5. ▪ a multi‐agency response is required to effectively address prescribing of unsafe complementary medications by unregistered health professionals.

Box – Manismithra Vatika tablets provided by a patient with an elevated blood lead level

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