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Data analysis considerations for pesticides determined by National Water Quality Laboratory schedule 2437

Scientific Investigations Report 2018-5007

National Water Quality Program
By:
https://doi.org/10.3133/sir20185007

Links

  • Document: Report (7.75 MB pdf)
  • Appendix: Table 4 (75.5 KB xlsx) - Summary statistics for the recovery of schedule 2437 pesticides in lab reagent spikes, and groundwater and surface-water spike samples
  • Data Releases:
    • USGS data release - National Water-Quality Assessment Project replicate surface water and groundwater pesticide data analyzed by the USGS National Water Quality Laboratory schedule 2437, water years 2013–15
    • USGS data release - Recovery data for surface water, groundwater and lab reagent samples analyzed by the USGS National Water Quality Laboratory schedule 2437, water years 2013–15
  • Download citation as: RIS | Dublin Core

Abstract

In 2013, the U.S. Geological Survey National Water Quality Laboratory (NWQL) made a new method available for the analysis of pesticides in filtered water samples: laboratory schedule 2437. Schedule 2437 is an improvement on previous analytical methods because it determines the concentrations of 225 fungicides, herbicides, insecticides, and associated degradates in one method at similar or lower concentrations than previously available methods. Additionally, the pesticides included in schedule 2437 were strategically identified in a prioritization analysis that assessed likelihood of occurrence, prevalence of use, and potential toxicity. When the NWQL reports pesticide concentrations for analytes in schedule 2437, the laboratory also provides supplemental information useful to data users for assessing method performance and understanding data quality. That supplemental information is discussed in this report, along with an initial analysis of analytical recovery of pesticides in water-quality samples analyzed by schedule 2437 during 2013–2015. A total of 523 field matrix spike samples and their paired environmental samples and 277 laboratory reagent spike samples were analyzed for this report (1,323 samples total). These samples were collected in the field as part of the U.S. Geological Survey National Water-Quality Assessment groundwater and surface-water studies and as part of the NWQL quality-control program. This report reviews how pesticide samples are processed by the NWQL, addresses how to obtain all the data necessary to interpret pesticide concentrations, explains the circumstances that result in a reporting level change or the occurrence of a raised reporting level, and describes the calculation and assessment of recovery. This report also discusses reasons why a data user might choose to exclude data in an interpretive analysis and outlines the approach used to identify the potential for decreased data quality in the assessment of method recovery. The information provided in this report is essential to understanding pesticide data determined by schedule 2437 and should be reviewed before interpretation of these data.

Suggested Citation

Shoda, M.E., Nowell, L.H., Stone, W.W., Sandstrom, M.W., and Bexfield, L.M., 2018, Data analysis considerations for pesticides determined by National Water Quality Laboratory schedule 2437: U.S. Geological Survey Scientific Investigations Report 2018-5007, 458 p., https://doi.org/10.3133/sir20185007.

ISSN: 2328-0328 (online)

Table of Contents

  • Foreword
  • Abstract
  • Introduction
  • Data-Analysis Considerations
  • Schedule 2437 Pesticide Data Characterization
  • Further Analysis
  • Summary
  • Acknowledgments
  • References Cited
  • Appendix 1. Supporting Tables and Figures

Additional publication details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Data analysis considerations for pesticides determined by National Water Quality Laboratory schedule 2437
Series title:
Scientific Investigations Report
Series number:
2018-5007
DOI:
10.3133/sir20185007
Year Published:
2018
Language:
English
Publisher:
U.S. Geological Survey
Publisher location:
Reston, VA
Contributing office(s):
National Water Quality Assessment Program
Description:
Report: vi, 458 p.; 2 Data releases; Table
Online Only (Y/N):
Y
Additional Online Files (Y/N):
Y