Pesticide Analysis? Methods, Regulations, and Reporting

Pesticide analysis is the process of detecting pesticide residues that may be present in agricultural products, foods, feed, or processed products; measuring their quantity; and comparing them with the limits set by relevant regulations. This analysis is especially critical for fresh fruits and vegetables, grains, legumes, dried foods, tea, spices, baby food, export products, and imported food controls.

Pesticide residues may originate from plant protection products used during the cultivation, storage, or transportation of the product. The main purpose of the analysis is to evaluate whether the product is safe for human health, whether it complies with legal limits, and whether it is suitable for entry into the target market.

In Turkey, pesticide residue limits are evaluated under the Turkish Food Codex Regulation on Maximum Residue Limits of Pesticides. This regulation sets maximum residue limits for pesticide residues that may be found in food and feed. The regulation was also amended in 2025. In the European Union, the European Commission’s EU Pesticides Database system is used for MRL queries; this database allows searches for active substances, food products, and maximum residue limits. Codex Alimentarius also publishes pesticide MRL data that may be used as a reference in international trade.

What is pesticide analysis?

Pesticide analysis is a laboratory analysis that determines whether certain pesticide active substances or metabolites are present in a sample and, if so, in what quantity.

These analyses generally seek to answer the following questions:

• Is there any pesticide residue in the product?
• If so, which active substances were detected?
• What is the detected amount in mg/kg?
• Is the result below or above the relevant MRL value?
• Does the product comply with Turkish, EU, Codex, or specific customer requirements?

Pesticide analyses are mostly performed using multi-residue screening methods. In other words, hundreds of active substances can be screened simultaneously in a single analysis. However, some substances may require special methods, different extraction procedures, or different instrument conditions.

Why are pesticide residues important?

Pesticides are used in agricultural production to combat harmful organisms. When used at the correct dose, at the correct time, and in an authorized manner, they contribute to production efficiency. However, residues may occur in products due to incorrect application, failure to comply with the pre-harvest interval, use of unauthorized active substances, or environmental contamination.

The importance of pesticide residues can be evaluated under four main headings:

1. Food safety: Residues above legal limits may pose a risk to consumer health.
2. Legal compliance: The product must comply with applicable regulations before being placed on the market.
3. Export risk: The target country’s MRL values may differ from those in Turkey. The EU, United Kingdom, United States, Gulf countries, or private retail chains may apply different limits or stricter requirements.
4. Commercial reputation: Non-compliant results may lead to product rejection, recall, border notification, customer loss, or loss of brand trust.

According to EFSA, strict rules are applied for pesticide residues in the EU, and food on the market is regularly monitored. More than 100,000 food samples are analyzed for pesticide residues in the EU every year.

Which products are tested for pesticides?

Pesticide analysis can be performed on a very wide range of product groups. The most commonly analyzed products are:

• Fresh fruits and vegetables: tomatoes, peppers, cucumbers, grapes, apples, citrus fruits, strawberries, cherries, apricots, figs.
• Dried fruits: dried figs, dried apricots, raisins, dates.
• Grains and legumes: wheat, rice, corn, lentils, chickpeas, beans.
• Oilseeds and nuts: sunflower seeds, sesame, hazelnuts, almonds, walnuts, pistachios.
• Tea, coffee, cocoa, and spices.
• Baby and young child foods.
• Processed foods: fruit juice, tomato paste, canned foods, frozen products.
• Feed and feed raw materials.
• Organic products.
• Export and import batches.

Each product group has a different risk profile. For example, field applications are more decisive for fresh fruits and vegetables, while storage pesticides may be more relevant for grains, and residues in tea and spices may originate from both cultivation and drying/storage processes.

How is pesticide analysis performed?

Pesticide analysis generally consists of the following stages:

1. Sample acceptance: The sample is delivered to the laboratory with appropriate packaging, quantity, and label information.
2. Homogenization: The product is chopped, mixed, and homogenized so that the analysis result represents the sample.
3. Extraction: Pesticide residues are separated from the sample using a solvent. QuEChERS-based extraction approaches are commonly used in multi-residue analyses.
4. Clean-up: Fat, pigments, sugars, organic acids, or other matrix components in the sample are reduced.
5. Instrumental analysis: Active substances are measured using advanced analytical instruments such as GC-MS/MS or LC-MS/MS.
6. Evaluation: Results are reported in mg/kg and compared with the relevant MRL values.
7. Reporting: Detected substances, measurement limits, uncertainty, method information, and conformity assessment are stated in the report.

The scope of analysis may vary from one laboratory to another. Therefore, when requesting “pesticide analysis,” it is necessary to clarify not only the name of the analysis, but also which active substances will be screened, which country or market limits will be used for evaluation, and which product matrix will be analyzed.

Difference between GC-MS/MS and LC-MS/MS

The two most commonly used instrument groups in pesticide analysis are GC-MS/MS and LC-MS/MS systems.

GC-MS/MS is a combination of gas chromatography and tandem mass spectrometry. It is suitable for pesticides that are more volatile, heat-resistant, and analyzable in the gas phase.

LC-MS/MS is a combination of liquid chromatography and tandem mass spectrometry. It is preferred for the analysis of more polar, heat-sensitive, or non-volatile pesticides.

In brief:

GC-MS/MS is generally used for volatile and thermally stable compounds.

LC-MS/MS is used for more polar, thermally sensitive compounds and compounds suitable for separation in the liquid phase.

In many comprehensive pesticide screening programs, the two instruments are used together. This is because a single instrument may not be ideal for analyzing all pesticides. For example, some organochlorine or volatile pesticides may be more appropriately analyzed by GC-MS/MS, while neonicotinoids, carbamates, or many modern active substances may be measured more efficiently by LC-MS/MS.

What is MRL and how is it interpreted?

MRL stands for “Maximum Residue Limit.” In Turkish, it is used as “Maksimum Kalıntı Limiti.” It refers to the highest legally permitted amount of pesticide residue in a food or feed product.

MRL is generally expressed in mg/kg.

For example:

• If the MRL for a pesticide in tomatoes is 0.50 mg/kg and the analysis result is 0.20 mg/kg, the result is below the limit.
• If the result for the same pesticide is 0.80 mg/kg, this indicates that the limit has been exceeded.
• However, MRL interpretation is not always just a “numerical comparison.” The following factors must also be considered:
• Is the product evaluated under the correct category?
• What is the residue definition of the active substance?
• Is the result evaluated together with measurement uncertainty?
• Which MRL system does the target country use?
• Is the product processed or fresh?
• Is the analysis result at LOQ level?
• Is the active substance authorized for that product?

In Turkey, evaluation is carried out according to the Turkish Food Codex, while for exports to the EU, the European Commission’s MRL database is taken into account. The European Commission’s database is an official information source where active substances, food products, and MRL values can be searched. In international trade, Codex MRL values may also be used as a reference for certain countries or trade agreements.

An important point is this: a product’s compliance with Turkish regulations does not always mean that it complies with the target export country’s requirements. Therefore, for export batches, the target country and customer specification must always be checked in advance.

Sampling and analysis process

The reliability of pesticide analysis does not depend only on laboratory equipment. Correct sampling is critical for accurate results. The sample must represent the batch to be analyzed.

The general process is as follows:

1. The batch is defined: The product’s lot/batch number, production site, harvest date, quantity, and shipment information are determined.
2. A representative sample is taken: Subsamples are taken from different points of the batch. A single crate, a single sack, or a single fruit often does not represent the entire batch.
3. The sample is combined: Subsamples are appropriately combined to form the laboratory sample.
4. The sample is packaged: The sample is sent in clean, leak-proof packaging that will not cause contamination.
5. The cold chain is maintained: Especially for fresh products, transport at an appropriate temperature is important to prevent deterioration.
6. The sample is delivered to the laboratory: The sample acceptance form should state the product name, batch information, requested analysis scope, and target regulation.
7. The analysis is performed: The laboratory selects the appropriate method, prepares the sample, and carries out instrumental analysis.
8. The report is issued: Results, analysis method, and evaluation information are reported.

Sampling errors may cause the analysis result to be misinterpreted for the entire batch. Especially for export products, the sampling plan should comply with the requirements of the buyer country or the customer protocol.

How to read the report

A pesticide analysis report generally includes the following information:

Sample information: Product name, sample acceptance date, batch/lot information, producer or sender information.

Analysis scope: Screened pesticide active substances or analysis method.

Result: Detected residue amount, usually given in mg/kg.

LOQ: Limit of Quantification, meaning the lowest level at which a substance can be reliably quantified.

LOD: Limit of Detection, meaning the lowest level at which the presence of a substance can be detected.

MRL: The legal maximum residue limit for the relevant product and active substance.

Evaluation: Comments such as compliant/non-compliant or below limit/above limit.

Method information: The analysis method used, instrument technique, and, where applicable, accreditation scope.

When reading the report, attention should be paid to the following points:

The expression “not detected” may not mean that the substance is absolutely absent. It usually means that it is below the detection or quantification limit of the relevant method.

A “< LOQ” result indicates that the residue is below the quantification limit.

If there is a result for an active substance, this value should be compared with the MRL for the relevant product category.

Correct product classification is very important when making MRL comparisons. For example, “fresh grapes,” “raisins,” and “wine grapes” may not be evaluated in the same way.

If there is no conformity assessment in the report, the result may need to be interpreted separately together with a regulatory expert, quality department, or laboratory.

Export, import, and special market requirements

Pesticide analysis is one of the most critical quality control steps in export and import. Different pesticide limits and control practices may apply especially in the EU, United States, United Kingdom, Russia, Gulf countries, and Far Eastern markets.

The main issues to consider in export are:

The MRL legislation of the target country.

The buyer’s specific specification.

Retail chains’ own limits.

Organic product requirements.

Lower limits for baby food or products intended for sensitive consumer groups.

Whether the active substance is banned in the target country.

Whether the product is fresh, dried, processed, or concentrated.

Some private buyers may apply stricter limits below the legal MRL. For example, special requirements such as “30% of the MRL,” “50% of the MRL,” “must not be detected,” or “certain active substances must not be present at all” may be requested.

In imports, the product’s compliance with Turkish regulations is evaluated. Pesticide residue limits in Turkey are determined under the Turkish Food Codex, and Ministry guidelines and regulatory provisions are taken as the basis.

Therefore, when requesting analysis for export or import, it is not enough to simply tell the laboratory “pesticide analysis.” The following information should also be provided:

• Product name and form.
• Target country.
• Customer specification.
• Organic/conventional product information.
• Requested active substance scope.
• Batch or lot information.
• Report language preference.
• Whether conformity assessment is requested.

Frequently asked questions

How many days does pesticide analysis take?

The duration depends on the laboratory’s workload, analysis scope, product matrix, and requested method. Routine multi-residue analyses can usually be completed within a few business days. For urgent export shipments, whether express analysis service is available should be discussed with the laboratory in advance.

How much sample is required for pesticide analysis?

The sample amount varies depending on the product type. For fresh fruits and vegetables, a representative sample of several kilograms may often be required. Different amounts may be sufficient for spices, tea, dried products, or concentrated products. The most accurate information should be obtained from the laboratory that will perform the analysis.

What does “not detected” mean?

“Not detected” means that the analyzed active substance is below the detection or quantification limit of the method used. Scientifically, this may not mean “zero residue.”

What is LOQ?

LOQ is the lowest level at which a substance can be reliably quantified. For example, if the LOQ is 0.01 mg/kg, residues below this level may not be quantitatively reported reliably.

What happens if the MRL is exceeded?

Exceeding the MRL may indicate that the product does not comply with the relevant regulations. In this case, placing the product on the market, exporting it, or importing it may become risky. Batch rejection, return, destruction, reassessment, or official notification processes may come into question.

Are all pesticides detected in the same analysis?

No. Multi-residue analyses may cover hundreds of active substances; however, some pesticides require special methods. Therefore, the analysis scope must be checked.

Is GC-MS/MS or LC-MS/MS better?

Neither is absolutely better than the other. Which instrument is suitable depends on the chemical structure of the pesticide. In comprehensive analyses, the two techniques may be used together.

Is pesticide analysis required for organic products?

Yes. Pesticide residue control is even more important for organic products. This is because organic certification and buyer specifications may require stricter evaluation than conventional products.

Is the Turkish MRL value sufficient for export?

Not always. In export, the target country’s legislation and the buyer’s special requirements must be taken into account. For the EU, the European Commission’s MRL database can be checked, while the Codex database may be used as an international reference.

Conclusion

Pesticide analysis is a critical control for food safety, legal compliance, and international trade. For an accurate analysis result, not only laboratory equipment but also correct sampling, correct analysis scope, correct regulatory selection, and correct report interpretation are important.

Especially for export, import, organic products, baby food, or products with special customer specifications, the product matrix, target market, active substance scope, and evaluation criteria must be clarified when creating the analysis request. This ensures regulatory compliance and minimizes commercial risks.