Shilajit is a mineral-rich resin that comes from rock, so it needs a laboratory test for heavy metals: no home check can detect them. A useful report gives lead, arsenic, mercury and cadmium results in ppm (mg/kg) for the batch you hold, with detection limits, measured against a named standard such as the WHO's 10 mg/kg for lead. If you are pregnant, take medication or have a health condition, follow your doctor's advice before taking shilajit.
This guide covers testing and published evidence only. It makes no claim about what shilajit does in the body.
At a glance
- Shilajit comes from rock, and a 2024 review found most reported metal levels below permissible limits "except in few studies"; no home test can detect metals.
- A report should list lead, arsenic, mercury and cadmium for the batch in your hand, with units, detection limits and a named standard.
- The most quoted limits are WHO's 10 mg/kg for lead and 0.3 mg/kg for cadmium; India's 2005 AYUSH export order adds 1 ppm for mercury.
- Published results vary: one US-sold shilajit held 10.5 µg/g of lead in a 2008 JAMA survey, while a 2025 Uttarkashi sample and twelve samples in a 2026 ICP-MS study were below detection or thresholds.
- A pass is a minimum, not a safety guarantee: WHO says no level of lead exposure is known to be harmless, so ask a doctor before taking shilajit in pregnancy or giving it to a child.
Why does shilajit need heavy-metal testing?
Because it is a mineral-rich exudate that comes from rock, and published analyses have found toxic metals in some samples and not in others. You cannot see, smell or taste lead or arsenic, so the only way to know what a batch holds is a laboratory test.
A 2024 review of the published literature on shilajit lists lead, arsenic, cadmium and mercury among the metals reported in it. The review found that most reported levels sat below the permissible limits it used, "except in few studies where exceeded levels were reported" (Hussain and Saeed, 2024). Contamination is not universal, but it has been found, and one sample tells you nothing about another.
Why care about small amounts? The World Health Organization says there is no level of exposure to lead that is known to be without harmful effects. In its lead fact sheet it notes that lead is stored in the teeth and bones, where it accumulates over time, and that some traditional medicines are a source of exposure. It adds that lead stored in bone may be released into the blood during pregnancy and expose the foetus.
Our guide to how to identify pure shilajit covers home checks for fillers; none can detect metals.
Which heavy metals should a shilajit report cover?
At minimum, lead, arsenic, mercury and cadmium. These are the four metals that India's Department of AYUSH made compulsory to test, batch by batch, for purely herbal Ayurveda, Siddha and Unani medicines meant for export, under an order announced in October 2005. A report missing any of them is incomplete.
- Lead was the metal found most often in a widely cited survey of Ayurvedic medicines, in 19.2 per cent of the products tested.
- Mercury has been found at very high levels in some rasa shastra medicines, which deliberately combine herbs with metals and minerals.
- Arsenic and cadmium appear in the same WHO and national tables as lead, and are part of the standard four-metal panel.
What limits apply to heavy metals in shilajit?
No single limit applies everywhere, and we found none written for shilajit by name. The figures most often quoted come from the WHO's recommendations for herbal medicines: 10 mg/kg for lead and 0.3 mg/kg for cadmium. India's 2005 export order adopted the WHO figures for lead, cadmium and arsenic and set mercury at one ppm.
The table sets out limits from the texts we opened, with the products each one covers. Parts per million (ppm), mg/kg and µg/g are the same measure.
| Standard | Applies to | Lead | Cadmium | Mercury | Arsenic |
|---|---|---|---|---|---|
| WHO recommendations (as listed in WHO's 2007 contaminants guideline) | Herbal medicines | 10 mg/kg | 0.3 mg/kg | Not listed | Not listed |
| India, Department of AYUSH order (2005) | Purely herbal Ayurveda, Siddha and Unani medicines for export | As WHO | As WHO | 1 ppm | As WHO |
| Canada (as listed by WHO, 2007) | Raw herbal materials | 10 ppm | 0.3 ppm | 0.2 ppm | 5 ppm |
| Canada (as listed by WHO, 2007) | Finished herbal products, per day | 0.02 mg/day | 0.006 mg/day | 0.02 mg/day | 0.01 mg/day |
| Thailand (as listed by WHO, 2007) | Herbal materials and finished herbal products | 10 ppm | 0.3 ppm | Not listed | 4 ppm |
Read the table with three cautions. First, the WHO's own guideline calls its table "examples" and says limits should be set nationally, so the country rows show approaches as of 2007, not necessarily current law. Second, the Indian order covers purely herbal medicines for export; a 2006 foreign-trade notification requires their containers to say "Heavy metals within permissible limits". Third, the WHO table we opened gives no WHO figure for arsenic or mercury, so a report claiming to meet "WHO limits" for those two should say which figure it used.
For dietary supplements, Saper's team noted in 2008 that neither US FDA regulations nor Indian policy then specified maximum metal concentrations or daily limits for domestic sale. For lead in food, the FDA now uses interim reference levels of 2.2 µg a day for children and 8.8 µg a day for females of childbearing age, as benchmarks for judging whether exposure is a potential health concern.
What did published tests of shilajit find?
Results vary from sample to sample. Some analyses found lead and arsenic below detection; others found metals at or above common limits. All are laboratory analyses, mostly of few samples, so none tells you what is in a jar you buy today.
- Saper and colleagues, 2008 (JAMA). The team analysed 193 Ayurvedic medicines bought online and found lead, mercury or arsenic in 20.7 per cent of them. One US-made product sold as shilajit contained 10.5 µg/g of lead, just above the WHO's 10 mg/kg; its mercury and arsenic were below the method's reporting levels. Every metal-containing product would, at the label's suggested use, have exceeded at least one standard for daily metal intake.
- Abdalla and Smith, 2013. A study from the FDA's Total Diet and Pesticide Research Center measured mercury in Ayurvedic supplements that were not rasa shastra. Its one shilajit sample held 0.760 µg/g by one method and 0.686 µg/g by another, below India's one-ppm export figure for mercury.
- Aldakheel and colleagues, 2022. This laboratory study of shilajit from India and Pakistan reported lead, arsenic and mercury above the permissible limits it used (abstract).
- Basavaraja and colleagues, 2025 (ACS Omega). A single traditionally collected sample from Uttarkashi showed lead and arsenic below detection; the authors give the detection limit as 0.01 to 0.05 ppm for most heavy metals. Mercury and cadmium are not in its results table.
- Kamgar and colleagues, 2026. Twelve shilajit samples from different regions, analysed by ICP-MS, had toxic metals "below established toxicity thresholds" (abstract).
Saper's study surveyed Ayurvedic medicines in general, not shilajit. Rasa shastra medicines, which combine herbs with metals, minerals and gems, were more than twice as likely to contain metals (40.6 per cent against 17.1 per cent), and 75 per cent of the metal-containing products claimed Good Manufacturing Practices.
How do you read the heavy-metal section of a shilajit report?
Check that the report belongs to your batch, that all four metals are listed with units, that any "not detected" result states its detection limit, and that each result is compared with a named standard. Then check who did the testing. Work through it in this order.
- Match the batch code. The code on the report should match the jar. A single certificate covering every batch describes one sample, tested once.
- Find all four metals. Lead, arsenic, mercury and cadmium should each have their own line. Anything not listed was not tested.
- Check the units. Results should be in ppm, mg/kg or µg/g, which are the same, or in µg per day for a stated amount. A bare number with no unit cannot be compared with anything.
- Read "ND" or "BDL" with its limit. Not detected means below what that method can measure, not zero. Saper's team could not report lead below 5 µg/g; the 2025 Uttarkashi study measured down to 0.01 to 0.05 ppm. A report should give the figure.
- Find the named standard. "Within limits" means little unless the report says whose limits: WHO, a national pharmacopoeia, or a buyer's own specification.
- Check the method and the laboratory. ICP-MS, atomic absorption or similar instrumental methods should be named. Look for accreditation and check that heavy metals fall within the lab's accredited scope.
Our article on how to read a ghee lab report explains batch codes and NABL accreditation; the point about accredited scope applies to shilajit reports too.
Does passing a limit mean shilajit is safe for you?
Not on its own. A concentration limit says how much metal is in each kilogram; what reaches you depends also on how much you take and for how long. A pass is the minimum to ask for. It is not a medical judgement, which is why anyone with a health concern should follow their doctor's advice.
The arithmetic shows why. At the WHO's 10 mg/kg for lead, each gram of material can hold up to 10 µg of lead, since 10 mg/kg is the same as 10 µg/g. That single gram would be more than the FDA's interim reference level of 8.8 µg a day for females of childbearing age, a benchmark for lead exposure from food. A result well below the ceiling therefore tells you more than a result just under it.
This is why some standards, such as Canada's for finished herbal products, are set per day. Given the WHO's warnings about lead, ask a doctor before giving shilajit to a child or taking it while pregnant or breastfeeding.
The short version
Shilajit comes out of rock, and published analyses have found lead, mercury and arsenic in some samples and none detectable in others, so every batch needs its own test. A useful report lists lead, arsenic, mercury and cadmium with units, detection limits and a named standard. The figures most often quoted are the WHO's 10 mg/kg for lead and 0.3 mg/kg for cadmium, and India's one ppm for mercury in herbal medicines for export. A pass is a minimum, not a safety guarantee, so follow your doctor's advice, especially in pregnancy or for children.
Sources
Further reading behind the figures above. Himdhara's own numbers — yields, batch results — come from our production records and the batch reports on the lab reports page.
- World Health Organization (2007). WHO guidelines for assessing quality of herbal medicines with reference to contaminants and residues. WHO.
- Saper RB, Phillips RS, Sehgal A, et al. (2008). Lead, mercury, and arsenic in US- and Indian-manufactured Ayurvedic medicines sold via the Internet. JAMA.
- Abdalla AA, Smith RE (2013). Determination of mercury in ayurvedic dietary supplements that are not rasa shastra using the hydra-C direct mercury analyzer. International Journal of Analytical Chemistry.
- Basavaraja D, Katkar R, Dhaka P, et al. (2025). Chemical Analysis of Native Himalayan Shilajit: An Evaluation of an Ayurvedic Formulation. ACS Omega.
- US Food and Drug Administration. Lead in Food and Foodwares. FDA.