Grantee Research Project Results

2024 Progress Report: Unregulated Organic Chemicals in Biosolids: Prioritization, Fate and Risk Evaluation for Land Applications

EPA Grant Number: R840245
Title: Unregulated Organic Chemicals in Biosolids: Prioritization, Fate and Risk Evaluation for Land Applications
Investigators: Olabode, Lola , Lee, Linda S. , Gan, Jay , McAvoy, Drew , Lono-Batura, Maile
Institution: Water Research Foundation , Water Environment Federation , University of Cincinnati , Purdue University , University of California Riverside
EPA Project Officer: Packard, Benjamin H
Project Period: October 1, 2021 through September 30, 2024 (Extended to September 30, 2026)
Project Period Covered by this Report: October 1, 2023 through September 30,2024
Project Amount: $1,497,907
RFA: National Priorities: Evaluation of Pollutants in Biosolids (2020) RFA Text | Recipients Lists
Research Category: Water Quality , Water , Water Treatment

Objective:

This research addresses “Better understanding of the occurrence, fate, and transport of chemical pollutants in land-applied biosolids, particularly those that may persist and/or accumulate in soils and biota.” There are five main objectives, each supported by a series of tasks with task leads:

Objective 1: Conduct data mining and modeling to prioritize UOCs by identifying chemicals with a higher propensity to be mobile and bioavailable following biosolids land applications.
Objective 2: Develop rapid standard methods for measuring mobile and bioavailable fractions of UOCs in biosolids.
Objective 3: Conduct field studies under different application scenarios to determine plant uptake, earthworm accumulation, leaching and runoff of the high-priority UOCs at sites in California, Virginia, Illinois, and Indiana to support a national approach.
Objective 4: Evaluate risk assessment fate and transport models for their prediction accuracy using literature, laboratory, and field derived data; and
Objective 5: Work closely with industry partners and community stakeholders to solicit input and develop risk-based optimal management practices to ensure safe land applications of biosolids nationwide.

Progress Summary:

Currently, 125 priority UOCs have been compared with existing reports and databases to identify potential carcinogens and endocrine disruptors. Thirteen UOCs were matched with IARC database (IARC 2021). Class 1A (potential carcinogen) - 1,2-Dichloropropane and Trichloroethylene, Class 2A (possible carcinogen) – N-Nitrosodimethylamine, and N-Nitrosodiethylamine, and Class 2B (probable carcinogen) – Digoxin, N-Nitrosopiperidine, 1,4-Dioxane, N-Nitrosopyrrolidine, N-Nitrosobutylamine, 4-Methyl 2-pentanone, 2,6 Dinitrotoluene, Di(2-ethylhexyl)-pthalate. Eight endocrine disrupting chemicals were identified. Thirteen UOCs were classified as Class 1 or 2 carcinogens, and 23 UOCs were identified as endocrine disruptors. A total of 47 UOCs were classified as high priority, and the remaining 78 UOCs were classified as low priority. Eight UOCs from this study were present in two of the three priority lists. These compounds included BDE-47, BDE-207, BDE-99, Tonalide, Sulfanilamide, Ofloxacin, Triclocarban, and Triclosan. The UCR team targeted a suite of 44 UOCs for analysis using LC-MS/MS. These results will be assessed throughout the project period.

Preliminary validation of biosolids and soil extraction methods for UOCs were completed in targeted sites in California, Indiana, Illinois, and Virginia. Field studies of the high-priority UOCs at these sites are ongoing. Though many UOCs were found in biosolids and fewer in the recycled water, only some UOCs were above the detection limits in the edible tissues of radish, broccoli, and spinach. The UCR team used Class A biosolids to substitute synthetic fertilizers at different rates and tertiary treated wastewater as the sole irrigation water source to cultivate three vegetables. Two cannabinoids, synthetic fragrances, and phthalates were occasionally detected in the vegetables at maturity. PFAS compounds were present in biosolids and recycled water, however they were not detected in any of the vegetable species. For those chemicals detected in vegetables, both recycled water and biosolids contributed to their occurrence, but the relative contributions depended on the specific UOC compounds. Human dietary intakes were estimated using the field derived concentrations. For individual UOCs, the estimated average yearly intake ranged from 0.122 to 154 mg per person. When all of the detected UOCs were considered, the annual dietary intake per person was estimated to be 307 mg. The potential human health risk due to the dietary consumption of vegetables grown with recycled water and biosolids are small. Given that both biosolids and recycled water were used simultaneously, the research findings highlight the potential safety of such beneficial reuse under standard agronomic practices. For the second vegetable study, the UOC concentrations in the vegetable roots showed that the three biosolids treatment levels did not result in significant differences in accumulation of chemical residues in vegetable roots, suggesting that uptake of UOCs from biosolids was limited due to low bioavailability of the target UOCs.

The Purdue investigative team will continue with the extraction and analysis of field samples, including snapshot of UOCs/PFAS concentration at a couple of sites for a second year. The team will continuously sample after biosolids application to assess mobility of PFAS through the soil column to establish background concentration of UOCs/PFAS in the fields. Results from the dry farmed area has never been applied with biosolids or treated water. Low background contamination was detected, but not expected to impact the assessment of PFAS mobility after the biosolids application of the area. Results of UOCs analysis at the DLD, showed predominance of pharmaceuticals, PCPs, and phthalates in the area. While cannabinoids, hormones, sweeteners, and the rubber derivative 6PPD-Q were not detected. The concentration of UOCs is related to the OC in soil, therefore suggesting UOCs sorption to OC in the top layers of the soil. A few technical problems were encountered with the instrumentation from the previous reporting period, and maintenance of the LC-MS/MS. The instrumentation problems impact the sample injection, processing, and the validation of methods. The delay in the method validation also delayed the rapid assay methods. Signals were lower than expected leading to re-extraction and analysis of some samples. The number and variety of compounds targeted poses a challenge for the non-PFAS UOC method validation, hence the data analysis requires more time than anticipated. Added sampling areas have increased workload. Due to a limited number of project personnel compared to that planned, the laboratory and data analysis portion of the second field study is taking longer than expected.

On March 25, 2024, the Water Research Foundation hosted a 5-hour facilitated workshop at Purdue University, designed to foster engagement among over forty stakeholders representing diverse groups, including academics, utilities, biosolids associations, consultants, regulators, and researchers. Input was gathered from stakeholders via an on-site workshop, which included presentations, a question-and-answer period, an open house session, and the use of a facilitator. Through this project, WRF, WEF, investigative team researchers, biosolids and utility stakeholders gained insights into how stakeholders view the three areas of inquiry: compound prioritization, effective communication and engagement approaches with wastewater treatment plants, and gaps/needs for informing systems-based solutions. Overall, the workshop provided a platform for stakeholders to exchange insights, address challenges, and explore collaborative opportunities in advancing research on UOCs in biosolids. Moving forward, the project aims to incorporate stakeholder feedback to accomplish the goals for each focus area and the project’s Objective 5: Work closely with industry partners and community stakeholders to solicit input and develop risk-based optimal management practices to ensure safe land applications of biosolids nationwide. The team continues to work with other grantees, industry, and biosolids community experts /stakeholders, and expanded outreach by participating at the W4170 annual meeting, the inaugural biosolids meeting of the MidWest Biosolids Association, and WEF’s Residual and Biosolids Specialty Conference in 2024, amongst several regional, local, and national meetings.

Overall, the project is approximately 60% complete with significant work anticipated to be completed in 2025. There were delays due to various levels of complexities in the field studies (Objective 3: Conduct field studies under different application scenarios to determine plant uptake, earthworm accumulation, leaching and runoff of the high-priority UOCs at sites in California, Virginia, Illinois, and Indiana to support a national approach). A site, where biosolids will be applied to new acreage for the first-time, did not start until Fall 2023. Approval to work at another site was not approved until the first quarter of 2024. All of the Purdue team field work (5 sites) includes both PFAS and UOCs, which requires different sample processing and analysis schemes. The team will be tracking compounds in soils, plants, run-off, and in a subset of the quarterly monitoring, well samples for up to 2 years.

Dr Jay Gan’s team at University of California at Riverside will need additional time to complete the following tasks.

Sample extraction and instrument analysis for soil, passive sampler, earthworm, and plant samples from the second vegetable study.
Sample collection and analysis for the fruit tree study.
Data analysis, including QA/QC, and write up results for review and publication.

Dr McAvoy at the University of Cincinnati would need time for Objectives 2 and Objectives 3 to be completed by Drs Linda Lee and Jay Gan before doing a final evaluation of risk assessment of fate and transport models for their prediction accuracy using literature, laboratory, and the field derived data.

Future Activities:

Prepare publication on vegetable study and harvest apples and mandarins from fruit tree study.
Manuscript submission for the extraction and analysis procedures for non-PFAS UOCs in biosolids and soil in final stages for an October 2024 submission.
Manuscript focused on evaluating methods for PFAS in biosolids including QuEChERS in final co-author review stage for an October 2024 submission to Talenta.
Complete the UOCs analysis in all the matrices sampled.
Complete the PFAS analysis for the irrigated farmed area in all matrices sampled.
Complete the 5- year snapshot for both the 1st and 2nd year sampling for also both PFAS and other UOCs.
Start the second year of surface soil monthly sampling.
Continue with the extraction and analysis for PFAS and non-PFAS UOCs as samples arrived from CA and VA sites.
Additional sampling of crops, groundwater, and surface soil.
Evaluation of a methodology for the extraction and analysis of the targeted non-PFAs UOCs in plants.
Re-initiate 2^nd tile-drained site identified since the first one did not work out due to low PFAS presence in the solids being applied to the site
Begin project on the new site in IL.
Begin the evaluation of fate and transport risk model formulations. Objective 4 Evaluate risk assessment fate and transport models for their prediction accuracy using literature, laboratory, and field derived data.
Plan a second/capstone stakeholder meeting(s) location (TBD).

References:

Warke, M. and McAvoy, D. Prioritization and Risk Assessment of Biosolids-Borne UOCs, Oral Presentation, Biosolids Stakeholders’ Mtg, March 25, 2024, West Lafayette, IN.
Lee, L.S. Unregulated Organic Chemicals (UOCs) in Biosolids: Prioritization, Fate, and Risk Evaluation for Land Applications. Midwest Biosolids Association First Conference Meeting, Beck Center, March 26, 2024, West Lafayette, IN
Warke, M. and McAvoy, D. Prioritization and Risk Assessment of Biosolids-Borne UOCs, Oral Presentation, EPA Biosolids Grantee Mtg, March 27, 2024, West Lafayette, IN.
Lee, L.S., PFAS Fate, Transport and Challenges in Waste Management. Virginia Biosolids Council hosted Lunch and Learn, June 13, 2024. Virtual.
Lee, L.S. Direct In Situ Measurement of PFAS Transformation & Leaching from Land-Applied Biosolids, WEFTEC Residuals and Biosolids Conference, June 19, 2024 OK City, OK
McAvoy, D. and Warke, M. Prioritization and Risk Assessment of Biosolids-Borne UOCs, Oral Presentation, W4170 Annual Meeting, June 25, 2024, Seattle, WA.
Lee, L.S., PFAS Transformation & Leaching from Land-Applied Biosolids, CSWEA Webinar Series, Virtual, July 31, 2024
Lee, L.S., PFAS Fate After Land-Application of Biosolids, Synagro Technical Advisors Meeting, August. 6, 2024. Nashville, TN
Lee, L.S. Per- & Polyfluoroalkyl Substances (PFAS) Fate & Transport. Indiana Water Summit, August 21-22, 2024. Indianapolis, IN
Lee, L.S., PFAS (& UOCs) Fate After Land-Application of Biosolids, Aug 23, 2024. SWANA-hosted virtual webinar
Lee, L.S., PFAS Fate & Transport, USDA PFAS Workshop, September 10, 2024. SWANA-hosted webinar, Arlington, VA
Lee, L.S., PFAS Fate After Land-Application of Biosolids, NACWA PFAS Workshop, September 17, 2024. Virtual
Audrey J. Braun, Nicole M. Dennis, and Jay Gan. Land Application of Biosolids: Accumulation of Unregulated Organic Chemicals (UOCs) in Vegetable Roots, Soil, and Passive Samplers. Environmental Sciences Department Symposium at the University of California- Riverside, September 25, 2024, Riverside, California.
Warke, M. and McAvoy, D. Prioritization of Biosolids-Borne UOCs, Science of the Total Environment 955 (2024) 177207
Alvarez-Ruiz R, Linda S. Lee, Youn J. Choi. Fate of Per- and Polyfluoroalkyl Substances at a 40-year Dedicated Municipal Biosolids Land Disposal Site Manuscript accepted 9/24/2024 for publication at Science of the Total Environment Fate of per- and polyfluoroalkyl substances at a 40-year dedicated municipal biosolids land disposal site
Audrey J. Braun, Nicole M. Dennis, and Jay Gan. Land Application of Biosolids: Bioaccumulation of Unregulated Organic Chemicals (UOCs) in Vegetables. The Society of Toxicology and Chemistry (SETAC) North America 45^th Annual Meeting, October 2024, Fort Worth, Texas.

Journal Articles on this Report : 2 Displayed | Download in RIS Format

Publications Views
Other project views:	All 20 publications	2 publications in selected types	All 2 journal articles

Publications
Type	Citation	Project	Document Sources
Journal Article	Warke M, McAvoy D. Prioritization of Biosolids-Borne UOCs. Science of the Total Environment. 2024;Dec (955):177207	R840245 (2024)	Abstract from PubMed Full-text: ScienceDirect - Full Text HTML Exit
Journal Article	Alvarez-Ruiz R, Lee LS, Choi Y. Fate of per-and polyfluoroalkyl substances at a 40-year dedicated municipal biosolids land disposal site. Science of the Total Environment, 2024;954, p.176540.	R840245 (2024)	Abstract from PubMed Full-text: Elsevier - Full Text HTML Exit

Supplemental Keywords:

sludge, transport models, field derived data

Relevant Websites:

Unregulated Organic Chemicals in Biosolids: Prioritization, Fate and Risk Evaluation for Land Applications Exit

Water Reserch Foundation 5125 Exit

Progress and Final Reports:

Original Abstract

The 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.