{"accessLevel": "public", "bureauCode": ["020:00"], "contactPoint": {"fn": "William Yelverton", "hasEmail": "mailto:yelverton.will@epa.gov"}, "description": "Spatiotemporal trends in PM2.5 chemical composition in the conterminous U.S. This dataset is not publicly accessible because: Non-EPA data owned by University of North Carolina at Chapel, Institute for the Environment. It can be accessed through the following means: Contact Saravanan Arunachalam at UNC Chapel Hill:  sarav@email.unc.edu. Format: N/A. \n\nThis dataset is associated with the following publication:\nCheng, B., K. Alapaty, and S. Arunachalam. Spatiotemporal Trends in PM2.5 Chemical Composition in the Conterminous U.S. during 2006-2020.   ATMOSPHERIC ENVIRONMENT. Elsevier B.V., Amsterdam,  NETHERLANDS, 316: 120188, (2024).", "distribution": [], "identifier": "https://doi.org/10.23719/1532458", "keyword": ["n/a"], "license": "https://pasteur.epa.gov/license/sciencehub-license-non-epa-generated.html", "modified": "2025-08-14", "programCode": ["020:000"], "publisher": {"name": "U.S. EPA Office of Research and Development (ORD)", "subOrganizationOf": {"name": "U.S. Environmental Protection Agency", "subOrganizationOf": {"name": "U.S. Government"}}}, "references": ["https://doi.org/10.1016/j.atmosenv.2023.120188", "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12212415"], "rights": null, "spatial": "-127.2509,23.3982,-65.8512,49.9291", "title": "PM2.5 Chemical Composition in the Conterminous U.S. during 2006-2020"}