Agrochemical Impacts on Human and Environmental Health: Mechanisms and Mitigation

W-1045:  The growing demand for food and fiber will place greater strain on agricultural production and increase the need for environmental stewardship. Agrochemicals are one of many tools used to ensure an abundant food supply. Judicious use of agrochemicals will demand practical knowledge of their fate and effects in agricultural and natural ecosystems. The goal of the W-1045 project is to develop and extend knowledge necessary for the advancement of science-based management strategies that prevent or mitigate adverse impacts of agrochemicals on human and environmental health.

Scientist working on samples.

What has the project done so far?

Since its early beginnings, W-1045 has effectively responded to western region stakeholder concerns about understanding the effects of pesticide transport and fate and the toxicological implications of agrochemical uses. This responsiveness includes their leadership in establishing three peer-reviewed scientific journals dealing with pesticide transport, fate, and toxicology, including the Bulletin of Environmental Contamination and Toxicology, the Archives of Environmental Contamination and Toxicology, and Residue Reviews, representing a short, quick-reading publication, a full research publication, and a review publication, respectively.  Today, the work of W-1045 scientists extends well beyond the boundaries of the western region. This growing collaboration among chemists, biologists, toxicologists, and ecologists with expertise in the basic and applied sciences is responding to emerging chemical fate and effect challenges in accordance with the need for realistic human and environmental exposure information. This group of land-grant university scientists/extension specialists, together with USDA-Agricultural Research Service (ARS) scientists, provides a unique amalgamation of research and extension capabilities. This project will continue working toward its goal to advance science-based strategies to prevent or mitigate unacceptable adverse agrochemical impacts on humans and the envi

Checking clothing exposure.

ronment while affording joint research-extension opportunities through multistate collaboration.

Impact Statements:

  • W-1045 members in Florida, California, and Washington State have taken leading roles in developing novel field-based technologies to reduce fumigant atmospheric emissions. These efforts have opened opportunities to develop effective product stewardship programs to reduce human inhalation exposure in agriculturally important regions facing expansive urban development.
  • Many environmental contaminants are strongly hydrophobic (insoluble in water) and therefore more likely to associate with the watershed sediment. Research by W-1045 California scientists is revealing the importance of sediment aging in regulating agrochemical desorption and potential bioavailability to nontarget aquatic organisms.
  • W-1045 scientists and extension specialists in the Pacific Northwest have characterized   non-lethal negative effects from agrochemical exposure that could effect survival of sensitive aquatic macroinvertibrates (animals with no backbone and that are visible without a microscope) and endangered fish species. This work can lead to the formulation of watershed management plans that more adequately protect endangered aquatic species while avoiding unnecessary burdens on agriculture and other pesticide users.
  • Environmental stressors, including pesticides, heavy metals, nutrients, and oxygen depletion, are detrimental to organisms and are a growing global concern with respect to environmental health and quality. W-1045 research in Kansas is generating important information at the cellular level of organisms to evaluate how they respond to a change in environmental stress. This information can be used to more effectively manage ecological systems and allow proactive rather than reactive strategies for restoring ecosystem health.
  • Pesticide exposures represent an important public health problem and present a challenge to identify meaningful opportunities for prevention. Oregon W-1045 scientists are using applied spatial scan statistics and geographic information systems (GIS) to identify geographically where serious medical outcomes occur across Oregon. This information is making it possible to use limited public health resources more wisely.
  • W-1045 scientists in New York have developed effective and economical electrochemical treatment technologies to clean up soil and water contaminated by agrochemicals.
  • Basic research by W-1045 Nevada scientists is showing evidence suggesting that semiconductor surfaces (e.g., titanium dioxide) may be involved in the formation of perchlorate from chloride and nitrate from atmospheric nitrogen. Understanding the source of perchlorate in the environment, whether naturally-occurring or man-made, enables the establishment of natural baseline values so that scientists can measure and develop mitigation strategies to decrease the man-made source of environmental perchlorate.
  • W-1045 scientists and extension specialists in the western and north central states are combining efforts to use biological monitoring to identify routes of occupational exposures to pesticide handlers and harvesters of treated crops. This effort will provide detailed exposure data that will in turn allow for more effective personal protective equipment use and field entry interval designations.
  • W-1045 university researchers, together with USDA-ARS scientists, have identified environmental factors and management practices that influence agrochemical losses from turf via runoff. They are also developing models to estimate the impact, under urban management practices, of new and existing chemistries on aquatic systems.

 

Checking for impacts in a nearby stream.

Drawing from W-1045’s multidisciplinary collaborations and expertise, basic and applied research will be needed to determine the exposure and risk to biota (including humans) from foliar, soil, water, and airborne agrochemical residues, and to develop appropriate measurement and mitigation strategies. This research direction will require (a) more appropriate biomarkers and analytical methods with better sensitivity, accuracy, and precision; (b) investigations to understand the mechanisms by which use practices and environmental factors influence agrochemical loss and bioavailability; (c) better understanding of sublethal biological effects of low-level chronic exposure; and (d) effective translations and delivery of the above results to inform stakeholders and policy makers.  The capacity of this research project has expanded to include state-of-the-art technology of genomics, proteomics, and metabolomics. This has made it possible to identify new and more representative biomarkers of agrochemical exposure and toxicology and to monitor the environmental fate of new genetically-modified plants with insecticidal proteins, such as Bt endotoxin in genetically-modified corn.

CONTACT:

Administrative Advisor, Ronald Pardini, ronp@cabnr.unr.edu