Pesticide Authentication by Portable
FTIR Spectroscopy

In this application note, we demonstrate how a portable FTIR spectrometer can be used to rapidly analyze pesticides before distribution, before mixing, and/or before application to crops.

In 2004, thousands of acres of crops in Spain, Italy and France were destroyed by the application of a counterfeit pesticide. The pesticide was offered at 20% discount and the packaging was identical to that of the expected product. In reality, the 20% discounted substance was metsulfuronmethyl and not the correct pesticide, rimsulfuron. The result was extensive destruction of produce and crops.

Portable FTIR aids in ensuring that correct pesticides are applied to fields and produce.

A series of pesticides were analyzed using the Agilent 4500a portable FTIR system outfitted with single refl ection diamond ATR sensor. The pesticides that were analyzed included cis-chlordane, trans-chlordane, aldrin, lindane and campheclor. Approximately 0.5 μL of each pesticide was placed on the diamond ATR sensor. The recorded spectra consisted of 64 co-added interferograms measured at 4 cm-1 resolution. Spectra were searched against the a commercially available pesticides library from ST Japan, and the identity of the sample pesticide was determined in less than one minute.

The pesticides that were selected for this demonstration are banned or severely restricted, as they are classified as persistent organic pollutants. These are all chlorine containing compounds that are toxic to humans and animals, as well as to insects.

FTIR spectroscopy can quickly and easily identify undiluted pesticides with a minimum of sample preparation. The combination of commercially available pesticide data bases combined with the performance and mobility of the Agilent 4500 and 5500 Series FTIR, enable rapid, on-site analysis of suspect product. Adulterated, contaminated or otherwise out-of-specifi cation pesticides can now be analyzed in locations where they are manufactured, shipped, received, stored and sold. Once pesticides are diluted for application to crops, the FTIR analyzers are capable of identification if the active ingredient level is > 5%.
For more dilute solutions, or for determining the level of residual pesticide in crops, other technologies are employed.

This technology offers port and border control officers the capability to spot check containers for content authenticity. This ensures that pesticide identity is verified prior to application in fields and farms and mitigates the risk of detrimental effects on health, produce, crops and the environment.

Excerpt from Agilent Technologies Application Note 5991-2531EN