Maximum Residue Limits (MRLs) Explained

There are no residue limits on this page, and that is deliberate. MRLs are legally binding, they differ by active substance, by crop and by destination, and they change on a rolling basis. Publishing a number here that someone ships against would be irresponsible. What this page does is explain how the systems differ — which is the part nobody explains well — and send you to the official database for every actual figure.

What an MRL is

A Maximum Residue Limit is the highest concentration of a pesticide residue legally permitted in or on a food. It is expressed in mg/kg, which is the same thing as ppm, and it is set per active substance, per crop, per jurisdiction.

The most common misunderstanding is worth clearing up immediately.

An MRL is not a safety threshold. It is derived from Good Agricultural Practice — the residue you would expect when a product is used correctly at the approved rate. It is then checked against toxicological reference values (ADI and ARfD) to confirm there is a wide safety margin. Exceeding an MRL is a legal and compliance failure. It does not automatically mean the food is unsafe, and the two questions should not be conflated in either direction.

The systems are structurally different

Not just different numbers — different logic about what happens when a substance is not listed at all. That is where consignments get caught.

European Union

How it works: Harmonised across all member states.
If a substance is not listed: 0.01 mg/kg
Where no specific MRL is set, a default applies.
Look it up: EU Pesticides Database (European Commission)

United States

How it works: EPA sets tolerances; FDA and USDA enforce them.
If a substance is not listed: No tolerance = not permitted
There is no general default — if no tolerance exists for that substance on that crop, any detectable residue is a violation.
Look it up: eCFR, 40 CFR Part 180

Japan

How it works: Positive List system.
If a substance is not listed: 0.01 ppm
A uniform limit applies to any substance without a listed MRL.
Look it up: Japan Food Chemical Research Foundation

United Kingdom

How it works: Own register since Brexit, initially mirroring retained EU limits and free to diverge.
If a substance is not listed: 0.01 mg/kg
Check separately from the EU — do not assume they still match.
Look it up: HSE pesticide MRL register

Codex (international)

How it works: Reference standards used by many markets that set none of their own.
If a substance is not listed: —
Useful where a destination has no national list, but it does not override one that does.
Look it up: FAO/WHO Codex pesticide residue database

The rule that governs a spray programme

If fruit from a block might go to several markets, the strictest applicable limit across all of them effectively governs how that block is farmed. You cannot decide the destination after the fact and hope the residue profile fits.

This is why growers building for export plan the residue programme around the destination list from the beginning of the season, and why "which markets is this block approved and programmed for?" is a better question than "is it compliant?".

The law is the floor, not the specification

Meeting the legal MRL is necessary and frequently not sufficient. Many European retailers impose their own limits on top of the law, and those are the ones that actually decide whether your fruit is accepted.

Strictest in practiceRetailer specification — often a percentage of the legal MRL, a cap on the number of detectable residues, or a restricted list of active substances

ThenThe legal MRL in the destination market

UnderneathToxicological reference values (ADI, ARfD) — the safety assessment the limit was checked against

A grower can be fully legal and still fail a buyer's specification. When a buyer says "we work to 33% of MRL and a maximum of four residues", that is a commercial standard, not a regulatory one, and it is contractual.

Where to look up an actual number

Always from the authority, never from a summary page like this one:

European Union — EU Pesticides Database (European Commission)

United States — eCFR, 40 CFR Part 180

Japan — Japan Food Chemical Research Foundation

United Kingdom — HSE pesticide MRL register

Codex (international) — FAO/WHO Codex pesticide residue database

If a number matters, take it from one of those, note the date you checked it, and re-check before the next season.

How to use this page. Visit Citrusdal is an independent guide, not an exporter, an agent or the industry body. Everything here is general orientation compiled from public sources — it is not commercial, legal or regulatory advice. Confirm anything you will act on with the producer, your own advisers and the relevant authority.