How should we read the difference between residue, limits and risk?

01

Four terms, four different questions

Residue is a measurement. MRL is a legal compliance limit. ADI and ARfD are health-based guidance values derived from toxicological evidence. The terms can appear in the same assessment, but they do not measure the same thing.

An MRL is generally established using residue levels expected when a pesticide is used according to authorised good agricultural practice. Consumer exposure is also checked against health-based values. The MRL’s main practical function, however, is to test whether a food and its production comply with the applicable rules.

ADI and ARfD are not simply the mg/kg value printed in a food test. They are usually expressed as exposure per kilogram of body weight. A laboratory result therefore needs to be converted into an exposure estimate using food-consumption and body-weight data before comparison.

02

What does an MRL exceedance mean?

If a result is above the current MRL for the relevant food–active-substance combination, the product is not legally compliant. Possible causes include an incorrect dose, failure to observe the pre-harvest interval, unauthorised use, environmental contamination or another application error. A field investigation is needed to establish the cause.

An exceedance may trigger risk-management action such as withdrawal, trace-back and enforcement. A separate acute and chronic dietary-exposure assessment is still required to characterise health risk. Slightly exceeding an MRL does not automatically mean poisoning, just as being below it does not mean absolute zero risk.

Public communication should avoid both extremes. “The limit was exceeded, so everyone was poisoned” skips the scientific assessment. “Below the limit means completely harmless” oversimplifies exposure and uncertainty. Compliance and health risk should be explained separately but together.

03

What goes into a health-risk calculation?

Long-term assessment compares estimated average dietary exposure with the ADI. Short-term assessment compares high-consumption and high-residue scenarios with the ARfD. The Joint FAO/WHO Meeting on Pesticide Residues evaluates toxicological reference values and residue estimates using scientific evidence.

The calculation includes more than a laboratory number. Body weight, the amount eaten in one sitting or over time, the edible portion and the active substance’s toxicological profile can all change the result. The same residue level in two different foods may therefore create different exposure.

Exposure to more than one pesticide also matters. Cumulative approaches are being developed for substances with similar modes of action, but it should not be assumed that every routine report evaluates all mixtures as a single number. The method used must be stated clearly.

04

Seven questions to ask when reading a test report

A screenshot of one number is rarely enough for interpretation. Sampling, laboratory method, measurement uncertainty and the date of the applicable rule are as important as the result itself. If a news or social-media post omits these details, avoid a definitive conclusion.

05

How are pesticide MRLs regulated in Türkiye?

In Türkiye, maximum pesticide-residue levels in food are regulated by the Turkish Food Codex Regulation on Maximum Residue Levels of Pesticides, with values set by food and active substance. The main regulation was published on 27 September 2021 and has since been amended.

Values can change as scientific assessments, authorisations and regulatory alignment evolve. An old table, article or report may therefore not contain the current limit. The Ministry of Agriculture and Forestry’s legislation and guidance pages should be checked for the latest value.

Public reporting should distinguish the laboratory finding, the legal-compliance decision and the health-risk assessment. This prevents both unnecessary alarm and the minimisation of a genuine non-compliance issue.