What is E555?

Complete guide to understanding E555 (Potassium Aluminosilicate) — an approved additive with CRITICAL safety assessment gaps and extreme aluminum exposure risks

🚨 CRITICAL REGULATORY FAILURE – SAFETY NOT ASSESSED – ALUMINUM EXPOSURE 40-55X TOLERABLE INTAKE: E555 (Potassium Aluminosilicate) is officially approved as a food additive in the EU. However, EFSA’s 2020 re-evaluation concluded that “the safety of potassium aluminium silicate (E 555) could not be assessed.” More critically: Calculated aluminum exposure from E555 when used as authorized (carrier for colorants at up to 90% relative to pigment) potentially EXCEEDS the tolerable weekly intake for aluminum from ALL sources by 40-55 TIMES. This represents the most severe regulatory concern identified in food additive oversight.

The Quick Answer

E555 (Potassium Aluminosilicate) is an approved additive used as a carrier for food colorants (and anti-caking agent) with incomplete safety assessment and EXTREME aluminum exposure concerns that exceed tolerable intake by 40-55 times.

What makes E555 uniquely critical and concerning: E555 represents perhaps the most severe regulatory gap in the EU food additive system. Unlike most approved additives where EFSA has completed comprehensive safety assessment, EFSA’s 2020 re-evaluation of E555 concluded the safety “could not be assessed” due to insufficient toxicological data. But more critically, EFSA’s calculation of aluminum exposure from E555’s authorized use (as carrier for colorants at up to 90% relative to pigment) found it could potentially exceed the tolerable weekly intake for aluminum from all sources by 40-55 TIMES. E555 is a textbook example of a regulatory failure: approved without adequate safety evidence, with potential aluminum exposure risks orders of magnitude beyond safe levels.

E555 presents the most severe regulatory concern of all food additives reviewed in this collection.

📌 Quick Facts

Chemical Name: Potassium Aluminosilicate; Potassium Aluminum Silicate
Type: Colorant carrier; anti-caking agent; food additive; inorganic compound
Chemical formula: K₂Al₂Si₁₄O₃₂·4H₂O (variable stoichiometry)
Found in: Any foods containing titanium dioxide (E171) or iron oxide (E172) colorants
Primary function: Carrier for food colorants (90% max relative to pigment)
EU Status: Officially approved BUT safety could NOT be assessed (EFSA 2020)
FDA Status: GRAS (Generally Recognized As Safe)
CRITICAL CONCERN: Aluminum exposure calculated at 297-388 mg/kg bw/week (EXCEEDS TWI by 40-55x)
Aluminum content: 20.4% (MUCH HIGHER than E554’s 7.8%)
Key issue: Safety assessment incomplete; aluminum exposure EXTREME

What Exactly Is It?

E555 is potassium aluminosilicate, a white powder used primarily as a carrier for food colorants — 100% synthetic, manufactured from potassium, aluminum, and silicon compounds.

Chemical composition: K₂Al₂Si₁₄O₃₂·4H₂O (typical; variable stoichiometry)

Appearance: White powder or crystalline mineral; odorless

Key properties:

– Colorant carrier: holds pigments in suspension; prevents settling
– Aluminum-rich: 20.4% aluminum (MUCH higher than E554’s 7.8%)
– Anti-caking: moisture absorption; maintains flowability
– Hydrophobic: makes particles water-repellent
– Heat stable: survives food processing
– Water-insoluble: remains as fine particles in products
– Potassium-containing: provides potassium alongside aluminum
– Particulate: distributed throughout colored food products

🔬 Understanding E555’s Critical Difference from E554: While both E554 and E555 are aluminum silicates with incomplete safety assessment, E555 is far MORE concerning. E555’s aluminum content (20.4%) is 2.6 times HIGHER than E554 (7.8%). E555’s authorized use as a carrier for colorants (up to 90% relative to pigment) creates theoretical aluminum exposure of 297-388 mg/kg bw/week. This is 40-55 TIMES the tolerable weekly intake. E555 represents the most extreme aluminum exposure risk of any approved food additive.

Where You’ll Find E555

E555 is found in any foods colored with titanium dioxide (E171) or iron oxides (E172) — which means thousands of food products.

Product Category	Function	Frequency	Concern Level
Vitamins & supplements (PRIMARY)	Colorant carrier	Very common	CRITICAL – high consumption of E555
Baking ingredients & mixes	Colorant carrier	Very common	CRITICAL – frequent use
Powdered foods with pigments	Colorant carrier	Common	HIGH
Any E171 or E172 colored products	Carrier	Extremely common	CRITICAL – ubiquitous

Key concern: Because E555 is used as the carrier for E171 (titanium dioxide – white pigment) and E172 (iron oxides – various colors), it’s found in virtually all white-colored or pigmented food products. This is extremely widespread.

The CRITICAL EFSA 2020 Finding

Most important and alarming finding: EFSA’s 2020 re-evaluation conclusion on E555 safety and aluminum exposure.

Official EFSA Panel statement on safety assessment:

“Considering that only very limited toxicological data and insufficient information on the physicochemical characterisation of both food additives were available, the Panel concluded that the safety of… potassium aluminium silicate (E 555) could not be assessed.”

Official EFSA Panel statement on aluminum exposure:

“Considering that potassium aluminium silicate (E 555) contains 20.4% aluminium… the maximum exposure to aluminium from potassium aluminium silicate (E 555) as carrier for E 171 could be up to 388 mg/kg bw per week and the maximum exposure to aluminium from potassium aluminium silicate (E 555) as carrier for E 172 could be up to 297 mg/kg bw per week.”

Critical context:

EFSA’s tolerable weekly intake (TWI) for aluminum from all sources: 1 mg/kg bw/week (7 mg/kg bw/week PTWI maximum)

Calculation:

– E555 aluminum exposure: 297-388 mg/kg bw/week
– Tolerable intake: 7 mg/kg bw/week
– EXCESS MULTIPLE: 42-55 times the tolerable intake
– Single use at maximum permitted level could exceed tolerable intake by ORDERS OF MAGNITUDE

🚨 MOST SEVERE REGULATORY CONCERN: EFSA calculated that aluminum exposure from E555 when used as authorized could be 40-55 TIMES the tolerable weekly intake. This is not a minor concern; this is an extreme regulatory failure where an approved additive carries calculated aluminum exposure risks that are orders of magnitude beyond safe levels.

Why This Is Worse Than E554

Comparison of aluminum exposure risks:

Additive	Aluminum Content	Calculated Exposure	vs. Tolerable Intake	Severity
E555 (as colorant carrier)	20.4%	297-388 mg/kg bw/week	40-55x EXCEEDS	CRITICAL
E554 (as anti-caking agent)	7.8%	1.58-2.13 mg/kg bw/week	Several-fold exceeds	HIGH
Tolerable Intake (comparison)	—	7 mg/kg bw/week PTWI	BASELINE	—

Key finding: E555 is far MORE concerning than E554. The difference is not just of degree but of orders of magnitude.

Why Safety Could Not Be Assessed

Data deficiencies for E555 (same as E554):

1. Insufficient toxicological data:
– Very limited toxicological studies
– No adequate chronic toxicity testing
– Inadequate genotoxicity data
– No sufficient carcinogenicity studies

2. Inadequate physicochemical characterization:
– Poor definition of chemical composition
– Insufficient particle size distribution data
– Variable stoichiometry not adequately specified
– Different manufacturing methods not properly characterized

3. Data gaps on bioavailability:
– Unknown how much aluminum is absorbed
– Unclear whether aluminum is released in digestive system
– Inadequate human bioavailability studies

Is E555 Safe? The Most Severe Regulatory Paradox

E555 represents perhaps the most extreme regulatory paradox in food safety: officially approved yet with unsafe aluminum exposure.

Question	Answer	Implication
Is E555 approved in EU?	YES – officially authorized	Legal to use in food
Has EFSA assessed E555 safety?	NO – safety could NOT be assessed	Safety status UNKNOWN
Is aluminum exposure safe?	NO – 40-55x tolerable intake	Potentially UNSAFE
Should consumers avoid E555?	Strongly recommended	Major health concern
Should regulatory action be taken?	URGENT action required	Critical regulatory failure

⚠️ CRITICAL ASSESSMENT: E555 is officially approved in the EU as a food additive. However, EFSA’s 2020 re-evaluation concluded that the safety “could not be assessed.” More critically, calculated aluminum exposure from E555 at authorized use levels is 40-55 TIMES the tolerable weekly intake. This represents the most severe regulatory concern identified in modern food additive oversight.

The Bottom Line

E555 is officially approved but represents the most severe regulatory failure, with incomplete safety assessment and aluminum exposure risks 40-55 times the safe limit.

Critical facts about E555:

It’s officially approved: E555 is in the EU approved additives list
But safety assessment is incomplete: EFSA explicitly concluded safety could NOT be assessed
Aluminum exposure is EXTREME: Calculated at 40-55 TIMES tolerable intake
Data gaps are severe: Insufficient toxicological and physicochemical data
Widespread exposure: Found in all E171/E172 colored products (thousands globally)
No emergency fix: Approval persists despite these critical concerns
Highest risk in supplements: Vitamin/supplement industry’s heavy use of E555 as colorant carrier

🚨 MOST SEVERE BOTTOM LINE: E555 (Potassium Aluminosilicate) is officially approved in the EU as a food additive, but this approval represents a critical regulatory failure. EFSA’s 2020 re-evaluation explicitly concluded that “the safety of potassium aluminium silicate (E 555) could not be assessed” due to insufficient data. Most critically, EFSA calculated that aluminum exposure from E555 at authorized use levels could reach 297-388 mg/kg body weight per week, which is 40-55 TIMES the tolerable weekly intake established for aluminum from all sources. This is the most extreme regulatory concern identified in this comprehensive food additive review. E555 should not be considered safe; it should be considered a critical food safety issue requiring urgent regulatory action.

Final Thoughts: The Most Severe Food Additive Regulatory Failure

E555 represents the most critical food safety regulatory failure examined in this entire research collection.

Why E555 is the most severe concern:

1. Safety assessment is incomplete: EFSA cannot assess safety (unlike most additives)
2. Aluminum exposure is extreme: 40-55 times tolerable intake (not just exceeding; far exceeding)
3. Exposure is widespread: Ubiquitous in colored food products globally
4. Use authorization is broad: Up to 90% as colorant carrier
5. Regulatory action absent: Despite these critical findings, approval continues

Why this matters more than E554: While E554 also fails safety assessment and exceeds aluminum tolerable intake, E555’s aluminum exposure risk (40-55 times) dwarfs E554’s risk (several-fold). E555 is orders of magnitude more concerning.

Consumer implications:

– E555 is in virtually any white-colored or pigmented food product
– Vitamin supplements are particularly high-risk
– Baking products with colorants contain E555
– Regulatory approval does NOT indicate safety
– Aluminum exposure from E555 may be unsafe at authorized levels
– Consumers concerned about aluminum should actively avoid E171/E172 colored products

Regulatory implications:

– E555 approval should be suspended pending complete safety assessment
– Aluminum exposure limits require urgent review
– Manufacturing practices should be questioned
– Consumer communication about this risk is overdue
– This represents a critical failure in food safety oversight

The bigger picture: E555 demonstrates that food additive approval systems can fail catastrophically. An additive can be officially approved while simultaneously lacking adequate safety data and carrying calculated exposure risks 40-55 times safe levels. E555 is a stark reminder that regulatory approval is not a guarantee of safety, and that consumers cannot assume all approved food additives have been properly assessed.

What is E555? – Complete guide to understanding Potassium Aluminosilicate