Analysis of Phosphine in food and feed via Headspace-GC-PFPD

Tentamus Agriparadigma, Laboratory based in Ravenna (Italy), has been active for over 30 years in the analysis of pesticide residues in food and feed.

In April 2020 the laboratory started a full revision of its method for the analysis of phosphine (phosphane and phosphide salts) in food and feed through the use of the most advanced instrumentation and the automation of all sensitive steps.

Phosphine is one of the most widely used fumigants. EU legislation sets maximum residue limits for the sum of phosphine and phosphides in foodstuffs within a range of 0.01 to 0.7 mg/kg, depending on the commodity. Several methods have been described for the analysis of phosphine, but currently no ISO or EN standard methods are available.

For this reason, the laboratory of Tentamus Agriparadigma has developed its own method based on the most recent scientific literature.

The method involves the development of phosphine from the sample by acid treatment and the subsequent determination of the gas by gas chromatography of the head space with a pulsed flame photometric detector and phosphorus filter.

To increase the representativeness of the sample, 100 ml bottles were used which required the use of a customized autosampler. The developed phosphine is taken from the autosampler with a gas syringe and analyzed by gas chromatography with a specific column for the analysis of volatile compounds.

The experts at Tentamus Agriparadigma have decided to use the (pulsed) flame photometry detector with phosphorus filter (PFPD). This particular type of detector is extremely specific.

The result is an extreme sensitivity, the absence of interfering signals and a linear response over a wide concentration range. All the steps have therefore been optimized to allow shorter analysis times and to increase productivity.

The method has been validated on numerous matrices of plant origin in accordance with the SANTE / 12682/2019 guidelines.
The limit of quantification was chosen equal to 3µg / kg (lowest validated concentration)

Accreditation according to ISO 17025:2018 is expected within 2020, which will make Tentamus Agriparadigma the first laboratory of the Group in Italy to have this important parameter accredited.

If you would like more information about this topic, please contact our Technical Manager Gian Piero Luciani gianpiero.luciani@agriparadigma.it