{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T23:23:05Z","timestamp":1788045785106,"version":"build-2784847793"},"reference-count":59,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T00:00:00Z","timestamp":1770163200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Life"],"abstract":"<jats:p>Environmental exposures are increasingly recognized as important drivers of ocular surface inflammation, yet their combined contribution to the onset, exacerbation, and clinical burden of allergic conjunctivitis (AC) has not been comprehensively synthesized. This systematic review evaluated the evidence linking air pollutants, aeroallergens, and indoor or occupational exposures with allergic conjunctivitis. The review was conducted according to PRISMA 2020 and AMSTAR-2 guidelines and registered in PROSPERO (CRD420251162399). PubMed, Web of Science, and Scopus were searched from inception to 18 September 2025. Two independent reviewers screened studies, extracted data, and assessed methodological quality using the MINORS tool. Owing to substantial heterogeneity, findings were synthesized narratively. Twenty-nine studies were included, encompassing more than three million outpatient visits. Consistent associations were observed between particulate matter, nitrogen oxides, sulfur dioxide, carbon monoxide, and ozone with increased AC incidence and symptom severity, with variations by age, sex, and season. Pollen and air pollutants frequently acted synergistically. Indoor exposures were associated with increased risk in children, while occupational settings demonstrated exposure\u2013response relationships. Experimental studies identified mechanisms involving epithelial barrier disruption, NF-\u03baB activation, and thymic stromal lymphopoietin signaling. Overall, environmental exposures substantially contribute to allergic conjunctivitis and may inform improved prevention and personalized clinical management.<\/jats:p>","DOI":"10.3390\/life16020271","type":"journal-article","created":{"date-parts":[[2026,2,4]],"date-time":"2026-02-04T12:51:56Z","timestamp":1770209516000},"page":"271","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Air Pollution, Pollen, and Indoor Exposures in Allergic Conjunctivitis: A Systematic Review"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0996-5007","authenticated-orcid":false,"given":"Clara","family":"Martinez-Perez","sequence":"first","affiliation":[{"name":"Department of Physics of Condensed Matter, Optics Area, University of Seville, Reina Mercedes S\/N, 41012 Seville, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0152-8141","authenticated-orcid":false,"given":"Ana Paula","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Instituto Superior de Educa\u00e7\u00e3o e Ci\u00eancias de Lisboa (ISEC Lisboa), Alameda das Linhas de Torres, 179, 1750-142 Lisboa, Portugal"},{"name":"Centro de Investiga\u00e7\u00e3o, Desenvolvimento e Inova\u00e7\u00e3o em Turismo (CiTUR)\u2014Polo Estoril, Avenida Condes de Barcelona, n.\u00ba 808, 2769-510 Estoril, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1080\/09603123.2022.2030465","article-title":"Short-term effects of ambient ozone on the risk of conjunctivitis outpatient visits: A time-series analysis in Pudong New Area, Shanghai","volume":"33","author":"Cheng","year":"2023","journal-title":"Int. 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