Grantee Research Project Results
High-throughput method development to acquire chemical data needed to inform environmental molecular lifecycles that guide sustainable chemical assessment
EPA Grant Number: R841118Title: High-throughput method development to acquire chemical data needed to inform environmental molecular lifecycles that guide sustainable chemical assessment
Investigators: Sullivan, Ryan , McDonough, Carrie , Isayev, Olexandr , Torres, Ana
Institution: Carnegie Mellon University
EPA Project Officer: Spatz, Kyle
Project Period: March 1, 2025 through May 1, 2025
Project Amount: $1,500,000
RFA: Advancing Sustainable Chemistry (2024) RFA Text
Research Category: Endocrine Disruptors , Green Chemistry , Chemical Safety for Sustainability
Objective:
Advancing sustainable chemistry requires the capability to predict persistent environmental and biological transformation products (TPs) formed from any chemical, and the environmental fate and persistence of these TPs. This informs the complete environmental molecular lifecycle from precursors to stable intermediates to final chemical end points that can focus further studies of the environmental and health impacts of synthetic chemicals, and inform comprehensive chemical alternatives assessment. The ability to assess environmental fate earlier in the chemical product design cycle is needed to avoid producing unsustainable chemicals at scale and making regrettable substitutions. We hypothesize that the automated science "Cloud Lab" at Carnegie Mellon along with recent advanced machine-learning informed computational chemistry methods we have developed can create faster methodologies to obtain this needed chemical data that enables prediction of environmental reaction networks.
Approach:
High-throughput methods using an automated laboratory will be developed and evaluated to determine physical-chemical properties that inform environmental phase partitioning, mobility, bioconcentration, and human exposure, including the use of new biomimetic columns. Reaction rate constants that describe persistence and the major transformation products will be assessed using protocols that subject each chemical to typical environmental reaction conditions. We will develop experiments for gas and aqueous-phase direct and indirect photolysis, and aqueous hydrolysis. Biological transformation will be assessed using liver S9 enzymes to produce typical metabolites, and in later stages using active wastewater sludge. Physical properties of major TPs will also be evaluated, along with their reactivity. The automated Cloud Lab will greatly reduce chemical analysis time and costs needed for these experiments.
Our recently developed machine learning-based computational chemistry models will be expanded to include halogenated organics and environmental reaction pathways such as gas and aqueous-phase oxidation, hydrolysis, and in later stages direct photolysis. These models produce accurate chemical predictions similar to high-level quantum chemical models but with far greater speed. The new experimental data will improve the computational predictions, especially of challenging-to-model molecular architectures such as pharmaceuticals and pesticides, polar or ionizable compounds, and for photochemical processes involving excited energy states
Expected Results:
The experimental and computational data combined will produce a predicted reaction network that describes the environmental molecular lifecycle of the persistent TPs produced from a given chemical with an assessment of the persistence, mobility, and bioconcentration factor of each major TP. Such understanding is a key data gap inhibiting the creation of comprehensive life cycle analysis frameworks that include TPs and their costs that our project addresses, enabling more accurate representation of the total costs incurred in later life stages that are usually externalized. This can reduce disproportionate impacts from emerging contaminants on underrepresented communities by enabling earlier alternatives assessment. These new data streams will be openly shared through a web interface and for use in chemical databases.
Supplemental Keywords:
Environmental organic chemistry, chemical alternatives assessmentProgress and Final Reports:
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.