2009S&T Water Sampling for Pesticides
2009 S&T Water Sampling for Pesticides
Problem Statement Pesticides analyzed by AXYS and CDFG -Chlorpyrifos and diazinon extracts sent to CDFG -Stopped in 2006 2006 and 2007 extracts on hold ·CDFG Issues with TPP surrogate Unclear whether it was related to spiking or extraction
Problem Statement • Pesticides analyzed by AXYS and CDFG – Chlorpyrifos and diazinon extracts sent to CDFG – Stopped in 2006 • 2006 and 2007 extracts on hold • CDFG – Issues with TPP surrogate • Unclear whether it was related to spiking or extraction
2008 Demonstration Project Conducted analysis of whole water(8 L) using MRES and 100 L samples using MRES at 6 sites Confirmation that MDLs are sufficient to detect compounds Comparison between collection methods to evaluate accuracy of method and potential for using MRES to analyze archived extracts
2008 Demonstration Project • Conducted analysis of whole water (8 L) using MRES and 100 L samples using MRES at 6 sites – Confirmation that MDLs are sufficient to detect compounds – Comparison between collection methods to evaluate accuracy of method and potential for using MRES to analyze archived extracts
Staff Recommendation Have all pesticide analyses conducted by AXYS Analytical using MRES method on 100 liter infiltrix system Slight increase to program cost (~$100/sample)
Staff Recommendation • Have all pesticide analyses conducted by AXYS Analytical using MRES method on 100 liter infiltrix system • Slight increase to program cost (~$100/sample)
Results·MDLs In general whole water have higher MDLs than 100 L;most within a factor of two 80.00 70.00 60.00 50.00 ◆一 Whole water 40.00 -Particulate 30.00 20.00 ◆-Dissolved 10.00 0.00 DDD(p.p) Chlordane,gamma Chlorpyrifos Diazinon Endosulfan I
Results - MDLs • In general whole water have higher MDLs than 100 L; most within a factor of two 0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 DDD(p,p ') Chlordane, gamma- Chlorpyrifos Diazinon Endosulfan I MDL (pg/L) Whole water Particulate Dissolved