Pesticide Testing

Analytical testing dots Pesticide Testing

Isotope Dilution GC/MS/MS Pesticide Testing

ALS Environmental offers the analysis of organochlorine pesticides by isotope dilution Gas Chromatograph/ Mass Spectroscopy/Mass Spectroscopy (GC/MS/MS), using our new Waters Quatro triple quadrapole.

It is well known that the analysis of organochlorine pesticides by traditional EPA methodologies that use Gas
Chromatographs with Electron Capture Detectors (GC/ECD) are often affected by the presence of PCB congeners (polychlorinated biphenyl congeners) and other co-extractable interferences causing false positive identification and/or over estimation. High biased results for organochlorine pesticides can lead to an overall lack of data confidence and unnecessary environmental actions.

Pesticide SprayerTo eliminate co-extractable and PCB congener interference, ALS Environmental has developed a unique method using isotope dilution with Large Volume Injection (LVI) and GC/MS/MS. Using standard extraction procedures combined with this analytical method, ALS Environmental is able to achieve detection levels up to 20 times lower than typically observed by ECD detection.

The triple-quad LVI/GC/MS/MS provides excellent selectivity in complex matrices by generating unique spectral fingerprints. These fingerprints provide unambiguous identification producing increased data defensibility. This enhancement is essential in further reducing co-extractable interferences. Isotopic standards increase the precision and accuracy in measuring the concentration of the pesticides. This method is applicable to water, soil/sediment and tissue matrices.

Triple-quad LVI/GC/MS/M

Diagram of the triple-quad LVI/GC/MS/MS. Image courtesy of Waters Corporation.

Analytical testing dots

Method Detection Limits and Method Reporting Limits

Organochlorine Pesticides
Water Soil Tissue
Compound MDL (ng/L) MRL (ng/L) MDL (μg/Kg) MRL (μg/Kg) MDL (μg/Kg) MRL (μg/Kg)
alpha-BHC 0.27 0.5 0.0069 0.05 0.025 0.1
gamma-BHC 0.15 0.5 0.011 0.05 0.041 0.1
beta-BHC 0.31 0.5 0.012 0.05 0.035 0.1
delta-BHC 0.19 0.5 0.011 0.05 0.047 0.1
Hexachlorobenzene 0.13 0.5 0.015 0.05 0.032 0.1
Heptachlor 0.17 0.5 0.0091 0.1 0.014 0.1
Chlorpyrifos 0.17 0.5 0.0072 0.05 0.023 0.1
Aldrin 0.47 1 0.012 0.1 0.047 0.1
Octachlorostyrene 0.28 1 0.017 0.1 0.094 0.1
Isodrin 1.1 2 0.029 0.2 0.043 0.2
Oxychlordane 0.72 2 0.14 0.2 0.18 0.50
Heptachlor epoxide 0.47 1 0.03 0.1 0.048 0.1
2,4’-DDE 0.19 0.5 0.0069 0.05 0.026 0.1
gamma-Chlordane 0.2 1 0.0081 0.05 0.024 0.1
alpha-Chlordane 0.15 0.5 0.0066 0.05 0.047 0.1
trans-Nonachlor 0.24 0.5 0.014 0.05 0.025 0.1
Endosulfan I 1.2 2.0 0.05 0.2 0.094 0.2
4,4’-DDE 0.13 0.5 0.0055 0.05 0.049 0.1
2,4’-DDD 0.11 0.5 0.0094 0.05 0.035 0.1
Dieldrin 2.3 5.0 0.098 0.5 0.073 0.5
Endrin 0.84 2.0 0.045 0.2 0.12 0.5
2,4’-DDT 0.13 0.5 0.015 0.05 0.048 0.1
cis-Nonachlor 0.31 2.0 0.015 0.2 0.049 0.2
4,4’-DDD 0.2 0.5 0.015 0.05 0.028 0.1
Endosulfan II 0.51 2.0 0.043 0.1 0.14 0.5
Endrin aldehyde 0.67 2.0 0.051 0.1 0.082 0.2
4,4’-DDT 0.23 0.5 0.014 0.05 0.043 0.1
Endosulfan sulfate 0.12 0.5 0.017 0.05 0.039 0.1
Methoxychlor 0.16 0.5 0.018 0.05 0.026 0.1
Endrin Ketone 0.7 2 0.036 0.1 0.13 0.5
Mirex 0.12 1 0.029 0.1 0.025 0.1