CATEGORY

Technical Notes

ALL CATEGORIES

A Comprehensive Guide to Pesticide Residue Analysis  

What is Pesticide Detection Analysis?

Scientists perform pesticide residue analysis to detect and measure residual substances that remain after a process, activity, or reaction. These substances include chemicals, pesticides, contaminants, or other foreign compounds. Experts use residue analysis to identify and quantify these residues so they can evaluate safety, enforce regulatory compliance, and assess environmental or health risks.

Analysts apply residue analysis in various fields:

  • Agriculture: Technicians test crops and food products for pesticide residues.
  • Food Safety: Inspectors check food products to ensure they contain safe levels of chemicals like antibiotics, heavy metals, or preservatives.
  • Pharmaceuticals: Laboratories examine meat, milk, eggs, and other animal products for drug residues to meet safety standards.
  • Forensic Science: Investigators analyze substances left at crime scenes, including drugs or explosives.

Why Do We Need to Analyze Pesticides?

We analyze pesticides because improper regulation or misuse can create serious health risks for humans, such as poisoning, reproductive issues, and neurological effects. Experts must test food, water, and air to verify that pesticide levels remain within the strict limits set by regulatory agencies.

Pesticides also harm environmental ecosystems, affecting soil, water, and biodiversity. They contaminate waterways, injure wildlife, and disrupt pollinator populations. Therefore, scientists continuously monitor these environmental factors to minimize negative impacts.

Since pesticide residues appear in food and crops, analysts collect and examine samples to ensure that these products meet safety standards. Farms also monitor pesticide application because overuse or misuse can cause pests to develop resistance. Regular analysis helps track resistance trends and guides better management practices.

How Do You Analyze Pesticides?

  1. Sample Collection:
    Begin by collecting a representative sample from the environment or product of interest—such as soil, plants, water, food, or air—to ensure accurate results.

  2. Sample Preparation:
    Prepare the sample by homogenizing it, extracting pesticide residues, and sometimes concentrating the extract. This process generally involves:

    • Extraction: Use solvents like acetone or hexane to pull pesticide residues from the sample matrix.
    • Clean-up: Remove interfering substances with techniques such as solid-phase extraction (SPE) or liquid-liquid extraction.
    • Concentration: Reduce the sample volume to boost the pesticide residue concentration, which improves detection.

    For more details on sample preparation, please refer to our technical notes.

Solid Phase Extraction (SPE)

Manual solid phase extraction cleans and concentrates samples before analysis by methods like gas chromatography (GC) or high-performance liquid chromatography (HPLC). Technicians use SPE cartridges with sorbents that capture analytes while letting contaminants pass. Experts select non-polar, polar, or ion exchange sorbents based on the target analyte’s characteristics. This process involves preparing the sample, conditioning the sorbent, loading the sample, washing, and eluting. SPE uses fewer solvents than liquid-liquid extraction and enhances separation and accuracy. [READ FULL TECHNICAL NOTE]

Liquid-Liquid Extraction (LLE)

Liquid-liquid extraction separates compounds by partitioning them between two immiscible solvents—typically one aqueous and one organic. This method relies on the target analyte’s physicochemical properties, such as pKa and LogP values. Industries like pharmaceuticals, food, and environmental analysis widely use LLE. Technicians mix the solvents, let the compounds distribute between the phases, and then separate them. LLE proves essential for analyzing complex samples. [READ FULL TECHNICAL NOTE]

Analytical Techniques for Pesticide Residue Analysis

Analytical techniques play a crucial role in ensuring food safety, protecting the environment, and meeting regulatory compliance. Analysts commonly use:

  • Gas Chromatography (GC) coupled with Mass Spectrometry (GC-MS): This technique excels at analyzing volatile and thermally stable pesticides.
  • Liquid Chromatography (LC) coupled with Mass Spectrometry (LC-MS/MS): This method suits polar, nonvolatile, and thermally unstable compounds.

At SCION, our chromatography instruments demonstrate exceptional performance in pesticide analysis.

Related Application Notes

  • Plant Protection Products Impurity Screening by GC-FID with GC-MS Confirmation:
    This note details a method that identifies and quantifies impurities in plant protection products, including pesticides, to meet EU and UK regulatory standards. Technicians initially screen using gas chromatography with flame ionization detection (GC-FID) and then confirm the results with gas chromatography-mass spectrometry (GC-MS).

  • Residual Solvent Analysis of Cannabinoid Products by Headspace GC-MS:
    This note investigates the need to monitor residual solvents in cannabinoid products due to increasing legalization and quality control demands. It emphasizes that technicians must track solvents used during cannabinoid extraction to ensure product safety and compliance by using headspace GC-MS efficiently.

  • EPA 515: Determination of Chlorinated Acidic Herbicides with a Two-Column System and Dual Electron Capture Detection:
    This method detects chlorinated acidic herbicides in water using gas chromatography with electron capture detection (GC-ECD). Technicians now prefer Methyl-8 over diazomethane for derivatization. A two-column system with dual ECDs allows simultaneous analysis and confirmation. The SCION 8500 GC system delivers effective separation, excellent repeatability, and low detection limits, offering a safer and more efficient approach.

  • Residual Solvent Analysis of Chemical Products by GC-FID with Hydrogen as a Carrier Gas:
    This note validates a method for analyzing residual solvents using gas chromatography with flame ionization detection (GC-FID) and hydrogen as the carrier gas. The study focused on eugenol—a terpene that makes up about 80% of clove leaf oil and exhibits insecticidal properties. Analysts followed the SANCO/3030/99 rev5 guidance document to ensure regulatory compliance.