Potassium Metabisulfite
The question

Is Potassium Metabisulfite safe in fruit juices?

CautionFruit juices

The main sulfite used in winemaking and home brewing ("Campden tablets"), also in cider and juices. It releases SO2 to prevent spoilage. Safe for most people but a trigger for sulfite-sensitive and asthmatic individuals; FDA requires labeling at 10 ppm or more.

What the research flags

  • Potassium metabisulfite acts as a sulfiting agent (releasing sulfur dioxide), so it can provoke reactions in sensitive individuals — especially asthmatics (roughly 3-10% react) — ranging from dermatitis, flushing, hypotension, abdominal pain and diarrhea to rare life-threatening asthmatic and anaphylactic reactions (Vally & Misso; Vally et al.)
  • FDA requires sulfiting agents present at 10 ppm or more in a finished food to be declared on the label (21 CFR 101.100) and prohibits sulfites on fruits and vegetables sold or served raw
  • EFSA's 2016 group re-evaluation set only a temporary ADI of 0.7 mg SO2 equivalents/kg body weight per day; in 2022 EFSA withdrew this temporary ADI, concluding the toxicity database was inadequate to establish a safe intake level

Regulatory
IARC Class: NL

Other fruit juices ingredients on file

Sources & references

  1. [1]
    Peer-reviewedPubMed / NCBI — pubmed.ncbi.nlm.nih.gov · ref 24834193
  2. [2]
    Peer-reviewedPubMed / NCBI — pubmed.ncbi.nlm.nih.gov · ref 19775253
  3. [3]
    RegulatoryInternational regulator — efsa.europa.eu · ref 4438
  4. [4]
    RegulatoryGovernment agency — section-101.100

Research disclaimer: Ratings reflect peer-reviewed research and regulatory assessments available at the time of publication, not the dose or formulation of any specific fruit juices product. This is not medical advice.