Validated UHPLC Methods for Melatonin Quantification Reveal Regulatory Violations in EU Online Dietary Supplements Commerce.
Level 5 - mechanism / opinion, no new human data
Level 5 by design analogy (laboratory analytical method development and bench product testing, not clinical CEBM)
PubMed 40572610 · doi:10.3390/molecules30122647
What was done
Researchers developed and validated ISO17025-compliant ultra-high performance liquid chromatography (UHPLC) methods coupled with diode array detection (DAD) or high-resolution accurate mass spectrometry (HRAM MS) to quantify melatonin in complex matrices. The methods were applied to test 50 dietary supplements purchased online: 25 from legal supply chains and 25 from suspicious sources advertising therapeutic melatonin content.
What was found
UHPLC-DAD was effective for simple formulations, while UHPLC-HRAM MS was necessary for products containing complex botanicals (such as passionflower, hop, hemp, lime tree, or lavender extracts) due to DAD selectivity constraints. High melatonin levels were confirmed in products from rogue internet pharmacies. Among products sourced from legal supply chains, 12% violated regulations through unauthorized health claims or by containing at least triple the maximum melatonin dose permitted in Belgium.
Why it matters
This work provides validated analytical methods for regulatory enforcement and shows that excessive melatonin doses and regulatory infractions occur even within regulated retail supply chains in the EU.
Limits
The sample size was limited to 50 products. Regulatory violations were evaluated specifically against Belgian national thresholds, which may not reflect legal limits in other jurisdictions. Specific numerical concentrations for individual products or cohorts were not reported in the abstract.
Cited by
- contradicts Melatonin is available by prescription only in almost all jurisdictions outside the United States, including the UK, Australia, and the European Union.