Potassium chloride is the acidity regulator the food industry lists as E508. In our table it is no risk identified: it takes no points off a product's score.
- The key finding, from EFSA: 'The Panel identified a human dose of 40 mg chloride/kg bw per day as a reference value for the assessment. Mean levels of exposure in all age groups were below or at this reference value, which indicates no safety concern. In some age groups (toddlers, children and adolescents), the 95th percentile exposure estimates were slightly above this reference value. The Panel concluded that the exposure to chloride from hydrochloric acid and its potassium, calcium and magnesium salts (E 507, E 508, E 509 and E 511) does not raise a safety concern at the reported use and use levels.' In the non-brand-loyal scenario mean exposure ranged from 2 mg/kg bw/day in the elderly to 42 mg/kg bw/day in toddlers; the 95th percentile from 5 to 71 mg/kg bw/day in toddlers (10.2903/j.efsa.2019.5751 (EFSA Journal 2019;17(7):5751, Re-evaluation of hydrochloric acid (E 507), potassium chloride (E 508), calcium chloride (E 509) and magnesium chloride (E 511) as food additives))
- No child flag. The class, and the points it costs, are the same for a child of any age.
- Where you meet it. It turns up in 20 of the 10,000 packaged foods scanned most on Open Food Facts, most often in chips, crackers and ready meals. Nine in ten of those foods are sold in Europe (counted 26 Sep 2026).
- 4 citations from EFSA, the FDA and EU law, each one below.
What Potassium chloride does to a score
A packaged food's additive subscore starts at 100 and loses points for each additive on the label; that subscore is a third of the final score. Potassium chloride takes no points off a product's score. Scan the pack in Sito and the score you get is the one for your own child's age, with this additive named in the reasons. How we score has the whole method.
See what is in your own cupboard
Scan a packaged food and Sito names the additives in it, then scores the product out of 100 for your child's age.
What the sources found
Every classification in our table comes from the citations below, and nothing else. Each finding is our one-line summary of what the source concluded, with the source and reference beside it.
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EFSA
10.2903/j.efsa.2019.5751 (EFSA Journal 2019;17(7):5751 — Re-evaluation of hydrochloric acid (E 507), potassium chloride (E 508), calcium chloride (E 509) and magnesium chloride (E 511) as food additives)
'The Panel identified a human dose of 40 mg chloride/kg bw per day as a reference value for the assessment. Mean levels of exposure in all age groups were below or at this reference value, which indicates no safety concern. In some age groups (toddlers, children and adolescents), the 95th percentile exposure estimates were slightly above this reference value. The Panel concluded that the exposure to chloride from hydrochloric acid and its potassium, calcium and magnesium salts (E 507, E 508, E 509 and E 511) does not raise a safety concern at the reported use and use levels.' In the non-brand-loyal scenario mean exposure ranged from 2 mg/kg bw/day in the elderly to 42 mg/kg bw/day in toddlers; the 95th percentile from 5 to 71 mg/kg bw/day in toddlers. -
EFSA
10.2903/j.efsa.2019.5751 (EFSA Journal 2019;17(7):5751)
Same opinion: 'Chloride is an essential nutrient and after absorption is distributed to organs and tissues'; the Panel considered chlorides to be of low acute oral toxicity and found no concern with respect to genotoxicity and carcinogenicity. The pre-existing ADI was 'not specified' (SCF 1991; JECFA 1965). -
FDA
21 CFR 184.1622 (Potassium chloride) — Part 184 "Direct Food Substances Affirmed as Generally Recognized as Safe"; verified against the current eCFR text
Potassium chloride is affirmed GRAS as a direct human food substance with no limitation other than current good manufacturing practice, and 'may be used in infant formula' in accordance with the Act — the strongest US signal available that this is not a child-risk additive. -
EU law
Regulation (EC) No 1333/2008 Annex II, consolidated text 02008R1333 — EN — 16.12.2024 — 059.001 (EUR-Lex ELI: reg/2008/1333)
E 508 potassium chloride authorised in the EU at quantum satis.
Why this class
Clean current EFSA and FDA status. These rows exist so that an unfamiliar additive is never treated as a bad one: a missing row costs a product nothing, and a clean row says so with citations.
Our confidence in this row's classification is high. Medium or low does not mean the evidence is weak; it means something about the row is still being pinned down, usually a regulatory status confirmed from one source rather than two.
Questions parents ask
Is Potassium chloride (E508) safe for kids?
No risk identified. No regulator finding we score, so a product keeps its full additive subscore in Sito. The current status is clean: 'The Panel identified a human dose of 40 mg chloride/kg bw per day as a reference value for the assessment. Mean levels of exposure in all age groups were below or at this reference value, which indicates no safety concern. In some age groups (toddlers, children and adolescents), the 95th percentile exposure estimates were slightly above this reference value. The Panel concluded that the exposure to chloride from hydrochloric acid and its potassium, calcium and magnesium salts (E 507, E 508, E 509 and E 511) does not raise a safety concern at the reported use and use levels.' In the non-brand-loyal scenario mean exposure ranged from 2 mg/kg bw/day in the elderly to 42 mg/kg bw/day in toddlers; the 95th percentile from 5 to 71 mg/kg bw/day in toddlers (EFSA, 10.2903/j.efsa.2019.5751 (EFSA Journal 2019;17(7):5751, Re-evaluation of hydrochloric acid (E 507), potassium chloride (E 508), calcium chloride (E 509) and magnesium chloride (E 511) as food additives)).
What is E508?
E508 is the E number for Potassium chloride, an acidity regulator. Open Food Facts tags it en:e508.
Next to it on the label
The E numbers either side of E508 in our table, then the closest acidity regulators by number.
- Potassium carbonates (E501), no risk identified
- Carbonates (E502), no risk identified
- Ammonium carbonates (E503), low risk
- Calcium chloride (E509), no risk identified
- Ammonium chloride (E510), no risk identified
- Sodium sulphates (E514), no risk identified