{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,6]],"date-time":"2026-11-06T21:17:24Z","timestamp":1793999844992,"version":"4.8.0"},"reference-count":43,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,3,20]],"date-time":"2024-03-20T00:00:00Z","timestamp":1710892800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000780","name":"AIRCOV project \u201cDetection of SARS-CoV-2 in the indoor air of Health and Educational Centers\u201d","doi-asserted-by":"publisher","award":["UGP-21-423"],"award-info":[{"award-number":["UGP-21-423"]}],"id":[{"id":"10.13039\/501100000780","id-type":"DOI","asserted-by":"publisher"}]},{"name":"European Regional Development Funds (ERDF) Operational Programme","award":["UGP-21-423"],"award-info":[{"award-number":["UGP-21-423"]}]},{"name":"European Commission under the European Regional Development Fund (ERDF) Operational Programme of the Valencia Region","award":["UGP-21-423"],"award-info":[{"award-number":["UGP-21-423"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxics"],"abstract":"<jats:p>A comprehensive study assessed indoor air quality parameters, focusing on relevant air pollutants such as particulate matter (PM10 and PM2.5), gaseous compounds (CO, CO2, formaldehyde, NO2) and volatile\/semi-volatile organic chemicals, as well as respiratory viruses (including SARS-CoV-2), fungi and bacteria in Spanish university classrooms. Non-target screening strategies evaluated the presence of organic pollutants inside and outside the classrooms. Saliva samples from teachers and students were collected to explore correlations between respiratory viruses in the air and biological samples. Indoor results revealed the punctual exceedance of recommended guidelines for CO2, formaldehyde (HCHO), volatile organic compounds (TVOCs) and PM in the least naturally ventilated classrooms. Significant differences occurred between the classes, with the least ventilated one showing higher average concentrations of CO2, HCHO, NO2, PM10 and PM2.5. A respiratory virus (rhinovirus\/enterovirus) was detected in the medium naturally ventilated classroom, although saliva samples tested negative. Suspect screening tentatively identified 65 substances indoors and over 200 outdoors, with approximately half reporting a high toxicological risk based on the Cramer rules. The study provides a comprehensive overview of indoor air quality, respiratory viruses and organic pollutants in university classrooms, highlighting the variations and potential health risks associated with ventilation differences.<\/jats:p>","DOI":"10.3390\/toxics12030227","type":"journal-article","created":{"date-parts":[[2024,3,21]],"date-time":"2024-03-21T04:34:46Z","timestamp":1710995686000},"page":"227","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Indoor Air Quality and Bioaerosols in Spanish University Classrooms"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6482-3159","authenticated-orcid":false,"given":"Esther","family":"Fuentes-Ferragud","sequence":"first","affiliation":[{"name":"Foundation for the Promotion of Health and Biomedical Research in the Valencia Region, FISABIO-Public Health, 21, Avenida Catalunya, 46020 Valencia, Spain"},{"name":"Environmental and Public Health Analytical Chemistry, Research Institute for Pesticides and Water, University Jaume I, S\/N, Avenida Sos Baynat, 12071 Castell\u00f3 de la Plana, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"L\u00f3pez","sequence":"additional","affiliation":[{"name":"Foundation for the Promotion of Health and Biomedical Research in the Valencia Region, FISABIO-Public Health, 21, Avenida Catalunya, 46020 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Miguel","family":"Piera","sequence":"additional","affiliation":[{"name":"Foundation for the Promotion of Health and Biomedical Research in the Valencia Region, FISABIO-Public Health, 21, Avenida Catalunya, 46020 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vicent","family":"Yus\u00e0","sequence":"additional","affiliation":[{"name":"Foundation for the Promotion of Health and Biomedical Research in the Valencia Region, FISABIO-Public Health, 21, Avenida Catalunya, 46020 Valencia, Spain"},{"name":"Public Health Laboratory of Valencia, 21, Avenida Catalunya, 46020 Valencia, Spain"},{"name":"Analytical Chemistry Department, University of Valencia, Edifici Jeroni Mu\u00f1oz, Dr. Moliner 50, 46100 Burjassot, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salvador","family":"Garrigues","sequence":"additional","affiliation":[{"name":"Analytical Chemistry Department, University of Valencia, Edifici Jeroni Mu\u00f1oz, Dr. Moliner 50, 46100 Burjassot, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miguel","family":"de la Guardia","sequence":"additional","affiliation":[{"name":"Analytical Chemistry Department, University of Valencia, Edifici Jeroni Mu\u00f1oz, Dr. Moliner 50, 46100 Burjassot, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9403-8258","authenticated-orcid":false,"given":"F. Xavier","family":"L\u00f3pez Labrador","sequence":"additional","affiliation":[{"name":"Foundation for the Promotion of Health and Biomedical Research in the Valencia Region, FISABIO-Public Health, 21, Avenida Catalunya, 46020 Valencia, Spain"},{"name":"Microbiology Department, University of Valencia Medical School, Av. de Blasco Ib\u00e1\u00f1ez, 13, 46010 Valencia, Spain"},{"name":"CIBERESP, Institute of Health Carlos III, Sinsesio Delgado Street, 4, 28029 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marisa","family":"Camar\u00f3","sequence":"additional","affiliation":[{"name":"Public Health Laboratory of Valencia, 21, Avenida Catalunya, 46020 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4930-8933","authenticated-orcid":false,"given":"Mar\u00eda","family":"Ib\u00e1\u00f1ez","sequence":"additional","affiliation":[{"name":"Environmental and Public Health Analytical Chemistry, Research Institute for Pesticides and Water, University Jaume I, S\/N, Avenida Sos Baynat, 12071 Castell\u00f3 de la Plana, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clara","family":"Coscoll\u00e0","sequence":"additional","affiliation":[{"name":"Foundation for the Promotion of Health and Biomedical Research in the Valencia Region, FISABIO-Public Health, 21, Avenida Catalunya, 46020 Valencia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"s35","DOI":"10.1186\/s12940-016-0101-8","article-title":"Reducing burden of disease from residential indoor air exposures in Europe (HEALTHVENT project)","volume":"15","author":"Asikainen","year":"2016","journal-title":"Environ. 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