preservative (surface treatment, fungicide) INS 231

Orthophenyl Phenol E231

phenolic compound — Primarily synthetic.

🇪🇺 EU: Approved
🇺🇸 USA: Approved
🇯🇵 Japan: Approved
🇦🇺 AU/NZ: Approved
🇨🇦 Canada: Approved
Scientific Name

2-Phenylphenol

CAS: 90-43-7

Data verified: 2026-04-04

Factual Regulatory Reference

This database provides factual regulatory information compiled from official government sources. It does not constitute medical, nutritional, or safety advice. Regulatory status varies by country and is subject to change. Always refer to your local regulatory authority for the most current information.

? Did You Know?

Beyond food, Orthophenyl Phenol is also used in medicine, industrial applications, household products. Its versatility makes it one of the most multi-purpose chemical compounds in everyday life.

To reach the Acceptable Daily Intake limit, a 60kg adult would need to consume approximately ~5 (if eating peel) oranges (200g each, consuming peel) in a single day. (This is a mathematical illustration, not a safety recommendation.)

Regulatory Analysis

Orthophenyl phenol sits at the intersection of food additive and pesticide regulation, classified as a food preservative (E231) in the EU but regulated as a pesticide by the EPA in the USA -- a jurisdictional split that subjects the identical substance to different safety assessment methodologies and burden-of-proof standards. The EPA's classification as a possible carcinogen introduces a risk characterization that does not directly translate to the EU food additive framework, where EFSA maintains an ADI of 0.2 mg/kg. The central unresolved question is the extent of penetration from treated citrus rind into edible flesh, as the safety assessment assumes surface residency while food preparation practices (juicing, zesting) systematically breach that assumption.

Detailed Regulatory Assessment

🇪🇺

European Union (EFSA)

approved Max: 12 mg/kg (on peel surface) mg/kg

RESTRICTED to citrus fruit surface treatment ONLY; must be declared on labels

Official EFSA Link
🇺🇸

United States (FDA)

approved Approved as pesticide for citrus fruits

Regulated as a pesticide by EPA; approved for post-harvest treatment of citrus

🇯🇵

Japan (MHLW)

approved Cat: 指定添加物

Approved for surface treatment; also approved as agricultural chemical (農薬としても承認)

Acceptable Daily Intake (ADI)

International Standard (JECFA)

0–0.2 mg/kg bw/day

mg/kg body weight per day

European Standard (EFSA)

0.2 mg/kg bw/day

Everyday Perspective

For a 60kg adult, this limit is roughly equivalent to consuming:

!
~5 (if eating peel) of oranges (200g each, consuming peel)
~2.4mg per serving
!
~20 servings of lemon zest (5g)
~0.6mg per serving

Natural Occurrence

This additive is not known to occur naturally in significant quantities.

Manufacturing

Method: chemical synthesis

Synthesized from phenol and benzene through chemical reactions, typically via oxidative coupling processes.

Applications Beyond Food

Medical

Antiseptic agent

Industrial

Used as disinfectant, antiseptic, and fungicide in non-food applications

Household

Disinfectant in household cleaning products

Frequently Asked Questions

What is Orthophenyl Phenol (E231)?
Orthophenyl Phenol (E231) is a preservative (surface treatment, fungicide) used in food products. It is phenolic compound and synthetic. A synthetic post-harvest fungicide applied to citrus fruit peels to prevent mold growth during transport and storage. Works similarly to E230 but is chemically different (has an -OH group). More effective against certain fungi than biphenyl. Also used as a disinfectant and antiseptic in non-food applications. Should be washed off before using citrus zest in cooking.
What is the ADI for Orthophenyl Phenol?
The Acceptable Daily Intake (ADI) for Orthophenyl Phenol is 0–0.2 mg/kg bw/day as established by JECFA (Joint FAO/WHO Expert Committee on Food Additives). ADI represents the amount that can be consumed daily over a lifetime without appreciable health risk.
What foods contain Orthophenyl Phenol?
Orthophenyl Phenol is used in various food categories including Citrus fruit (surface treatment only). It is used as a preservative (surface treatment, fungicide) in these products.
Is Orthophenyl Phenol the same as OPP?
Yes, Orthophenyl Phenol is also known as OPP, 2-Phenylphenol. These are different names for the same substance.