Prioritizing Landfill Contaminants for Environmental Remediation

Research Issue

Dumping site of municipal and industrial waste (background) and retention pond (foreground). USDA Forest Service photo by Ryan Vinhal.

Landfills in the United States represent an important potential source of water pollution, generating millions of liters of leachate or contaminated groundwater every day. Such pollution can negatively impact human health if leached offsite. Therefore, many actions, from preventative measures to reactive remediation activities are implemented to decrease the risks associated with landfill pollution. In recent years, increased interest in sustainability has led to a larger focus on on-site remediation, which can involve activities such as microbial remediation, in situ injection treatments, or the “green liver” approach of phytoremediation of inorganics and organics. However, the composition of landfill leachate is dynamic, changing over time and space due to chemical, physical, and societal factors. Thousands of potentially harmful contaminants can exist within leachate, making it difficult to objectively determine which contaminants at a site to target with remediation activities. Therefore, there is a need for a method that quantitatively prioritizes landfill contaminants for remediation.    

Our Research

Phytoremediation landfill planting (foreground) at a municipal solid waste landfill (background).To address this need, we developed a pollutant prioritization tool that systematically prioritizes contaminants according to reported toxicity values. The tool incorporates publicly available toxicity data to quantitatively rank contaminants. In addition, the tool is easily customizable to address community-specific health concerns, such as cancer or endocrine disruption. We identified 500 landfill leachate contaminants reported in the literature and have utilized this tool to prioritize 322 that had available toxicity data. Over 60% of the top 40 most-toxic contaminants identified in this study are not included in regulatory lists for landfill leachate. Regulatory lists do not consider all possible contaminants, especially newer classes of pollutants that were recognized after the lists were created (e.g., pharmaceuticals, personal care products, contaminants from electronic wastes and plastics). Therefore, remediation activities based on these lists may not address all the most harmful contaminants produced by landfills. We are currently using this tool to prioritize pollutants from two landfill sites where we implemented agroforestry phytoremediation buffer systems to reduce the transport of these pollutants. These phytoremediation systems are included in our regional phytotechnologies network in the Great Lakes Basin

Expected Outcomes

This tool can be utilized by researchers, engineers, site managers, and other industry professionals to systematically prioritize landfill contaminants for remediation activities and other environmental applications. The tool can be easily integrated with global metabolomics profiling to establish a comprehensive understanding of contaminants at the site level. Further, this tool may help to identify newer classes of contaminants at landfills that have yet to be included on regulatory lists.  

Research Results

Rogers, Elizabeth R.; Zalesny, Ronald S.; Lin, Chung-Ho. 2021. A systematic approach for prioritizing landfill pollutants based on toxicity: Applications and opportunities. Journal of Environmental Management. 284(1–4): 112031-.

Rogers, E.R.; Zalesny, R.S. Jr.; Lin, C-H. 2021. Integrating novel methodologies from the benchtop to the plot scale in an environmental cleanup project. In: University of Missouri Center for Agroforestry (UMCA) Annual Research Review; University of Missouri – Columbia; January 27, 2021; online at 3:16 (ORAL)

Rogers, E.R.; Zalesny, R.S. Jr.; Lin, C-H. 2020. Analytical techniques, sap flow methodologies, environmental education: integrating diverse disciplines in phytotechnologies research. Short Rotation Woody Crops Operations Working Group, University of Minnesota – Duluth (Duluth, MN), University of Minnesota – Extension, Short Rotation Woody Crops Webinar Series (from Rhinelander, WI); October 13, 2020. (ORAL)

Research Participants

Principal Investigators

  • Elizabeth R. Rogers, USDA Forest Service, Northern Research Station- Pathways Intern; University of Missouri – Columbia- PhD Student
  • Chung-Ho Lin, University of Missouri – Columbia, Center for Agroforestry, Columbia, MO
  • Ronald S. Zalesny Jr., USDA Forest Service, Northern Research Station- Supervisory Research Plant Geneticist


  • Last modified: April 16, 2021