Ultra-Trace Pyrethroids in Surface and Waste Waters with a Simplified Benchtop Extraction Step and Sensitive LC-MS/MS Analysis
New Organic Monitoring Techniques
Oral Presentation
Prepared by A. Pierri
Weck Laboratories, 14859 Clark Ave., Industry, CA, 91745, United States
Contact Information: agustin.pierri@wecklabs.com; 626-336-2139
ABSTRACT
As our population continues to grow, and our climate becomes more unstable, there is overwhelming amount of pressure on both our food and water supplies. The increased pressure on agricultural activities typically means more reliance on pesticides, which can then impact local water supplies through agricultural runoff. These impacted water supplies affect not only wildlife, but also human populations due to the small divide between agricultural and residential areas. With this in mind, the California Central Valley Water Board has adopted new, very low concentration goals for six pyrethroid pesticides in wastewater effluent and surface water ranging from 0.2 to 10 ng/L.
This paper presents a modification of EPA method 1660 suitable for the requirements of the low concertation goals established by the Central Valley Water Board. This new method allows for the determination of bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, and permethrin in surface water and wastewater effluents at low to sub part-per-trillion reporting limits. Whereas the original method used a cumbersome extraction procedure and HPLC with UV detection, this modification leverages the extreme sensitivity of modern triple quadrupole LC-MS/MS systems and uses a much simpler benchtop extraction. The analytes are salted out of the water and extracted with solvent in a small volume microextraction. The extraction takes into account the hydrophobicity of the target analytes and ensures that they are extracted from the surface of the sampling container, as well as from any suspended solid material present in the sample. This presents a significant advantage over conventional liquid-liquid or solid-phase extraction techniques.
New Organic Monitoring Techniques
Oral Presentation
Prepared by A. Pierri
Weck Laboratories, 14859 Clark Ave., Industry, CA, 91745, United States
Contact Information: agustin.pierri@wecklabs.com; 626-336-2139
ABSTRACT
As our population continues to grow, and our climate becomes more unstable, there is overwhelming amount of pressure on both our food and water supplies. The increased pressure on agricultural activities typically means more reliance on pesticides, which can then impact local water supplies through agricultural runoff. These impacted water supplies affect not only wildlife, but also human populations due to the small divide between agricultural and residential areas. With this in mind, the California Central Valley Water Board has adopted new, very low concentration goals for six pyrethroid pesticides in wastewater effluent and surface water ranging from 0.2 to 10 ng/L.
This paper presents a modification of EPA method 1660 suitable for the requirements of the low concertation goals established by the Central Valley Water Board. This new method allows for the determination of bifenthrin, cyfluthrin, cypermethrin, esfenvalerate, lambda-cyhalothrin, and permethrin in surface water and wastewater effluents at low to sub part-per-trillion reporting limits. Whereas the original method used a cumbersome extraction procedure and HPLC with UV detection, this modification leverages the extreme sensitivity of modern triple quadrupole LC-MS/MS systems and uses a much simpler benchtop extraction. The analytes are salted out of the water and extracted with solvent in a small volume microextraction. The extraction takes into account the hydrophobicity of the target analytes and ensures that they are extracted from the surface of the sampling container, as well as from any suspended solid material present in the sample. This presents a significant advantage over conventional liquid-liquid or solid-phase extraction techniques.
