Phosphonic acid dosage

What is phosphonic acid?

Phosphonic acid (CAS 13598-36-2) is an organophosphorus compound used as an antifungal agent or as a degradation residue of phosphonates. It is notably present in phytosanitary formulations based on fosetyl-aluminium, used to combat fungal diseases such as mildew on vines, fruit trees or market garden crops.

Although its effectiveness is recognized, phosphonic acid persists in plants, soils and the environment after treatment, which requires rigorous monitoring of its residues.

Why measure phosphonic acid?

Phosphonic acid analysis is crucial in several contexts:

• Monitoring of phytosanitary residues in plant foodstuffs
• Verification of compliance with MRLs (maximum residue limits) defined by European regulations (EC regulation no. 396/2005)
• Quality control of plant raw materials intended for human or animal food or for processing
• Assessment of environmental pollution linked to the use of phosphonates (irrigation water, agricultural soils)
• Securing exports to demanding markets such as Japan or the United States

Many retail chains now impose stricter thresholds than European regulations, particularly for grapes, citrus fruits, salads and products intended for children.

Available analytical methods

YesWeLab offers several dosing techniques depending on the matrix and the thresholds to be reached:

• LC-MS/MS (liquid chromatography coupled with mass spectrometry): reference method, sensitive and specific, suitable for fruits, vegetables, extracts, powders, etc.
• Ion chromatography: recommended for the analysis of water, fertilizers and inorganic matrices
• GC-MS (in some cases, after derivatization), less used but complementary for certain complex matrices

The detection limits obtained are compatible with the lowest MRLs, typically in the order of mg/kg (ppm) or µg/kg (ppb) depending on customer requirements.

Affected matrices

The phosphonic acid assay test is applicable to a wide range of agricultural and environmental matrices:

• Fresh fruits and vegetables: grapes, apples, citrus fruits, salads, tomatoes, melons, etc.
• Processed products: juices, purees, plant extracts
• Food supplements of plant or algal origin
• Animal feed: fodder, silage, plant concentrates
• Phosphonate-based fertilizers or foliar formulations
• Drainage water, irrigation water, groundwater
• Contaminated cultivated soils or substrates

Regulatory context

Phosphonic acid is regulated as a residue of plant protection products. It is subject to crop-specific MRLs, published in the annexes to Regulation (EC) No 396/2005. It may also be monitored in the context of:

• Official control plans for phytosanitary residues (DGCCRF, DGAL)
• Certification audits (AB, GlobalG.AP, Demeter, etc.)
• Export requirements for plant-based food consignments

Its dosage is also relevant in soil decontamination or environmental monitoring processes in agricultural areas.

Why go through YesWeLab?

At YesWeLab, we work with ISO 17025-accredited laboratories that specialize in plant protection residue analysis and environmental monitoring. Our services include:

• Selecting the analytical method best suited to your matrix
• Validation of results according to current standards (regulation (EU), Codex, export requirements)
• Comprehensive reports, usable for your quality controls, customer audits or regulatory files
• Personalized scientific support for non-conformities or abnormal results

Our digital platform allows you to efficiently manage your samples, quotes, results and history.

Need to analyze phosphonic acid in your products or soils?

YesWeLab helps you ensure the safety, regulatory compliance, and traceability of your agricultural products or plant ingredients.
Contact us now for a personalized study or a quick quote.