Grantee Research Project Results
2024 Progress Report: Elucidating the occurrence of known and emerging chemical contaminants in wastewater biosolids and the influence of treatment and management processes on their fate, mobility and bioavailability
EPA Grant Number: R840248Title: Elucidating the occurrence of known and emerging chemical contaminants in wastewater biosolids and the influence of treatment and management processes on their fate, mobility and bioavailability
Investigators: Hale, Robert C. , Song, Bongkeun , Guardia, Mark La , Luellen, Drew
Institution: Virginia Institute of Marine Science , Hampton Roads Sanitation District
EPA Project Officer: Packard, Benjamin H
Project Period: September 1, 2021 through July 31, 2024 (Extended to July 31, 2026)
Project Period Covered by this Report: September 1, 2023 through August 31,2024
Project Amount: $1,486,562
RFA: National Priorities: Evaluation of Pollutants in Biosolids (2020) RFA Text | Recipients Lists
Research Category: Water Quality , Water , Water Treatment
Objective:
1) Advance understanding of the composition, bioaccessibility, persistence, toxicity and mobility of chemical pollutants in wastewater sludges, biosolids and receiving soils; 2) Evaluate the influence of wastewater source and treatment choice on these; and 3) Assess sludge pollutant effects on critical wastewater treatment and soil microbial processes.
Progress Summary:
Preparations and relocation of the VIMS chemistry labs and offices to a newly constructed on-campus building commenced in August 2024. This was required due to periodic HVAC outages resulting in disruptive temperature and humidity fluctuations in the previous building. Instrument moves and recalibrations were performed by qualified vendor technicians following reinstallation.
Malfunctions of two project-critical instruments detailed in the previous report were rectified, specifically the laser direct infrared (LDIR) imaging system and the UPLC associated with the time-of-flight mass spectrometer. The repaired LDIR was reinstalled and is operational in the new research facility. Issues with the old UPLC were solved by replacement with a new UPLC using non-EPA funds. Its installation followed relocation of the QTOF MS to the new facility.
The utility of HLB SPE columns for extraction of biosolids-related contaminants was investigated. These were effective for retaining the more polar analytes but recoveries of non-polar analytes were poor. In response, we are investigating the use of C18 columns either in tandem with the HLB columns or in parallel on separate aliquots.
Discussions began with EPA regarding hiring a post-doc to replace the loss of an integral project team member. Funding for this was finalized in late Aug 2024. A search was initiated and over 120 individuals applied.
In summer 2024, VIMS hosted an NSF-funded REU (Research Experience for Undergraduates) student from U. Miami. She participated in investigations of sample preparation techniques for the analysis of microplastics in biosolids. The latter were obtained from a wastewater treatment facility partner. The LDIR was used to identify and enumerate microplastics present. Most MPs observed were in the 20-100 um size range. While polyethylene is the polymer used in largest volumes, it was not the dominant type identified. The biosolid used for method evaluation studies had been subjected to thermal hydrolysis by the treatment facility, i.e., exposed to temperatures (170oC). This exceeded the melting point of polyethylene (100-140oC).
Future Activities:
After post-doc arrival (anticipated May 2025) we will complete investigations of solid phase extraction and mass spectrometric methods for detecting targeted and non-targeted chemical contaminants in wastewater/sludge matrices. Much effort in recent years has pursued polar emerging contaminants of concern. However nonpolar contaminants are more likely to associate with sludge but be disproportionately mobilized from solids by high organic carbon concentrations present.
Two students have applied to the Hale lab/VIMS graduate program (Fall 2025). One has specifically indicated interest in participating in aspects of the biosolids project.
References:
Presentations
Hale, R.C. “Elucidating the occurrence of known and emerging chemical contaminants in wastewater biosolids and the influence of treatment and management processes on their fate, mobility, and bioavailability.” National Priorities: Evaluation of Pollutants in Biosolids. Grantee Meeting. Purdue University, W. Lafayette, IN. March 2024.
Hale, R.C. Microplastic pollution, not just an issue for marine organisms. Invited ACS Pittsburgh (PA) Section Environmental Lecture. Online. Feb 2024.
Jarratt, J., Hale, R.C., Mainor, M. Purification and characterization of microplastics in complex wastewater biosolids. VIMS REU Program. Aug 2024.
Jarratt, J., Hale, R.C., Mainor, M. Purification and characterization of microplastics in complex wastewater biosolids. Invited presentation for Hampton Roads Sanitation District (HRSD) staff. Online Sept. 2024.
Journal Articles:
No journal articles submitted with this report: View all 10 publications for this projectSupplemental Keywords:
wastewater residuals, environmental chemistry, toxicsProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.