Validating Analytical Protocols to Determine Selected Pesticides and PCBs Using Routine Samples

Area of Science:

• Environmental Chemistry
• Analytical Chemistry

Background:

• Validation of analytical protocols is essential for reliable environmental monitoring.
• Routine samples are underutilized for assessing the trueness of novel analytical methods.
• Organochlorine compounds in environmental matrices require robust analytical validation.

Purpose of the Study:

• To provide recommendations for validating analytical protocols using routine environmental samples.
• To present a case-study on validating analytical methods for pesticides and polychlorinated biphenyls in water and sediment matrices.
• To assess the analytical uncertainty associated with the developed protocols.

Main Methods:

• Validation of two analytical procedures using Gas Chromatography-Mass Spectrometry (GC-MS).
• Analysis of over 30 routine water and sediment samples collected over nine months.
• Application of conventional uncertainty estimation for water and bias estimation for inhomogeneous sediment matrices.

Main Results:

• The validated analytical methodology for water matrices achieved acceptable recoveries with a combined uncertainty of 20-30%.
• Sediment matrix analysis yielded reliable results, with analytical variability ranging from 25-35% under intermediate conditions.
• The study successfully demonstrated the application of routine samples for method validation.

Conclusions:

• Routine sample analysis is a viable and recommended approach for validating analytical protocols for environmental matrices.
• The developed GC-MS methods are suitable for analyzing pesticides and polychlorinated biphenyls in water and sediment.
• This methodology offers a practical approach to assess the trueness of analytical methods for organochlorine compounds.