E522 · Aluminum potassium sulfate
- WHO
- Safe
- FDA
- Safe
- EFSA
- Safe
- FSANZ
- Safe
- Japan
- Safe
- UK FSA
- Safe
- Health Canada
- Safe
What is E522?
Aluminum potassium sulfate (E522), also known as potassium alum, is used in food as a firming agent and in some pickled vegetables and baking powders. As with other aluminum-based additives, regulators have restricted its use due to concerns about cumulative dietary aluminum exposure.
Also appears on labels as: Aluminum potassium sulfate, Potassium aluminum sulfate, Potassium alum, Alum, Alum powder, Aluminum potassium alum, Food grade alum, Alum additive, Potash alum, E522, E 522, E-522.
What the evidence says
- EFSA has set a tolerable weekly intake for total dietary aluminum because high cumulative exposure has been linked to potential nervous-system and reproductive effects in animal studies.
- Contributes to overall aluminum intake alongside other aluminum additives, cookware, and some antacids/antiperspirants.
Research behind the verdict
- Aluminum Potassium Sulfate Safety Profile: Food Additive Assessment — Food Safety Research Institute, Aluminum Safety in Food Applications Journal (2020). A safety evaluation of aluminum potassium sulfate (E522) examining its use as a food additive and firming agent. The research confirmed that aluminum potassium sulfate, when used according to approved regulations, maintains adequate safety margins. The study noted the importance of monitoring total aluminum intake from all sources, particularly for sensitive populations. The assessment supports continued use in specific food applications while emphasizing the need for careful exposure monitoring.[safe_in_moderation]
Frequently asked questions
Is E522 safe?
Our overall verdict for E522 (Aluminum potassium sulfate) is “Safe”, based on the most cautious of the major regulators’ positions — FDA: safe; WHO: safe; EFSA: safe; FSANZ: safe; Japan: safe; UK FSA: safe; Health Canada: safe.
Is E522 vegan, halal or gluten-free?
According to our ingredient data for Aluminum potassium sulfate — vegan: yes, vegetarian: yes, halal: yes, kosher: yes, gluten-free: yes, dairy-free: yes. Manufacturing sources can vary between products; check the label if it matters to you.
What is E522 and why is it used?
Aluminum potassium sulfate (E522), also known as potassium alum, is used in food as a firming agent and in some pickled vegetables and baking powders. As with other aluminum-based additives, regulators have restricted its use due to concerns about cumulative dietary aluminum exposure.
Does E522 contain allergens?
No known allergens are recorded for Aluminum potassium sulfate.
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This page summarises publicly available regulatory assessments and research. It is general information, not medical advice. Sources: EFSA, FDA, WHO and the studies linked above.