Pesticides in Surface Water Downstream of and Near Agricultural and Developed Land in Hawai‘i, 2015–19

Scientific Investigations Report 2024-5071
Prepared in cooperation with the State of Hawai‘i Department of Agriculture
By: , and 

Links

  • Document: Report (13 MB pdf)
  • Data Releases:
    • USGS Data Release - Pesticide concentrations in water samples and quality-control samples collected at surface-water sites in Hawai‘i, 2016–19
    • USGS Data Release - Pesticide, organic-contaminant, and wastewater-indicator results for passive samplers deployed in surface water and groundwater in Hawai‘i, 2015–19
    • USGS Data Release - Surface-water sites in Hawai‘i where pesticides were assessed, 2015–19
  • Download citation as: RIS | Dublin Core

Abstract

Pesticides and pesticide degradates (herein referred to as pesticides) in surface water were assessed at 78 sites on 4 Hawaiian Islands (Kauaʻi, Oʻahu, Maui, and Island of Hawaiʻi) during 2015–19. Each site was downstream of or near agricultural land, developed land, or both. Most (58) sites were streams; the remaining sites were canals, ditches, anchialine pools, coastal ponds, and the nearshore ocean. Pesticides in water at each site were assessed by collection of one to four water samples, by a weeks-long deployment of a passive sampler, or both. Passive-sampler extracts and water samples, which consisted of fair-weather samples and storm samples, were analyzed for as many as 253 pesticides that consisted of 129 herbicides, 101 insecticides, and 23 fungicides.

A total of 117 pesticides were detected in water. Of these, 30 pesticides were detected at more than 20 percent of their assessment sites and thus were considered “common” pesticides. The common pesticides included 17 herbicides (ametryn, atrazine, bentazon, bromacil, diuron, hexazinone, metolachlor, propazine, simazine, triclopyr, prometryn, and degradates of atrazine [4], diuron, hexazinone, and prometryn); 8 insecticides (carbaryl, dinotefuran, fipronil, flubendiamide, imidacloprid, methoxyfenozide and 2 degradates of fipronil); and 5 fungicides (azoxystrobin, metalaxyl, propiconazole, a degradate of chlorothalonil, and a degradate of thiophanate-methyl and benomyl). Common pesticides typically were present more frequently in storm samples than in fair-weather samples. A mixture of two or more pesticides was detected in 86 percent of the water samples and in water during every passive-sampler deployment.

About 92 percent of all pesticide detections had concentrations less than 100 nanograms per liter. Pesticide concentrations were less than Federal aquatic-life benchmarks (ALBs) for vertebrates and typically were less than ALBs for invertebrates, nonvascular plants, and vascular plants. Acute ALBs were exceeded by acetochlor, atrazine, carbaryl, chlorpyrifos, cis-permethrin, diazinon, diuron, halosulfuron methyl, and imidacloprid in storm samples at one to four sites. ALBs for invertebrates were exceeded by clothianidin, diazinon, fipronil, and imidacloprid in fair-weather samples, during passive-sampler deployments, or both at 1 to 17 sites. Federal drinking water standards were available for only five pesticides detected in water, and the standard for atrazine was exceeded in one storm sample. Pesticide concentrations did not exceed any Federal human-health benchmarks, but many of the detected pesticides did not have a benchmark.

Suggested Citation

Johnson, A.G., Kennedy, J.J., and Alvarez, D.A., 2024, Pesticides in surface water downstream of and near agricultural and developed land in Hawai‘i, 2015–19: U.S. Geological Survey Scientific Investigations Report 2024–5071, 94 p., https://doi.org/10.3133/sir20245071.

ISSN: 2328-0328 (online)

Table of Contents

  • Acknowledgments
  • Abstract
  • Introduction
  • Methods—Assessment of Pesticides in Surface Water in Hawai‘i, 2015–19
  • Methods—Management and Analysis of Pesticide Results
  • Results—Pesticide Occurrence in Surface Water
  • Limitations of Pesticide Assessment
  • Suggestions for Future Pesticide Monitoring
  • Summary
  • References Cited
  • Appendix 1. Amounts of restricted-use pesticides sold in Hawai‘i, 2014–19
  • Appendix 2. Methods Used to Collect Water Samples, Deploy Passive Samplers, and Prepare Passive-Sampler Extracts
  • Appendix 3. Quality-Control Samples Associated with Water Samples and Passive Samplers
  • Appendix 4. Pesticides Analyzed in Water Samples and Passive Samplers Collected and Deployed in Hawai‘i During 2015–19
Publication type Report
Publication Subtype USGS Numbered Series
Title Pesticides in surface water downstream of and near agricultural and developed land in Hawai‘i, 2015–19
Series title Scientific Investigations Report
Series number 2024-5071
DOI 10.3133/sir20245071
Year Published 2024
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Pacific Islands Water Science Center
Description Report: ix, 94 p., and 3 data releases
Online Only (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details