{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T05:52:39Z","timestamp":1775713959561,"version":"3.50.1"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T00:00:00Z","timestamp":1775692800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pediatr."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Mercury is a persistent environmental contaminant that can cross the placenta and accumulate in fetal tissues. While its neurotoxic effects are well established, its potential association with allergic diseases in children remains unclear. Understanding how early-life mercury exposure relates to the burden of allergic conditions is important for child health and environmental risk assessment.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a systematic review and meta-analysis of observational studies reporting allergic outcomes in children with measured mercury exposure. PubMed and Embase were searched from inception to October 2025. Studies were eligible if they assessed prenatal or postnatal mercury exposure and reported at least one allergic outcome. Random-effects meta-analysis was used to estimate pooled prevalence of allergic outcomes reported in studies.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Sixteen studies were included. The pooled prevalence among mercury-exposed children was 6.2% (95% CI, 1.8\u201318.8%) for asthma, 18.6% (95% CI, 9.0\u201334.5%) for atopic dermatitis, 14.4% (95% CI, 3.2\u201346.2%) for eczema, 15.8% (95% CI, 3.3\u201350.9%) for allergic rhinitis, and 22.3% (95% CI, 13.2\u201335.2%) for wheezing. Heterogeneity was high (\n                      <jats:italic>I<\/jats:italic>\n                      \u00b2\u2009&amp;gt;\u200990%). Studies from East Asia, which reported higher mercury exposure and fish intake, showed greater allergic disease proportions than European cohorts.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Allergic diseases were frequent among populations in which mercury exposure was assessed, with regional and exposure-timing differences contributing to heterogeneity. The findings highlight the need for harmonised, prospective studies to clarify the role of mercury exposure in childhood allergic disease development.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fped.2026.1776559","type":"journal-article","created":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T05:20:30Z","timestamp":1775712030000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Early-life mercury exposure and allergic diseases in childhood: systematic review and meta-analysis"],"prefix":"10.3389","volume":"14","author":[{"given":"Qiming","family":"Liang","sequence":"first","affiliation":[{"name":"Department of Pediatrics, Baoshan Branch of Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maosong","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Baoshan Branch of Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hongliu","family":"Mao","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Baoshan Branch of Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,9]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"878","DOI":"10.3390\/life15060878","article-title":"Global burden of allergies: mechanisms of development, challenges in diagnosis, and treatment","volume":"15","author":"Alska","year":"2025","journal-title":"Life (Basel)"},{"key":"B2","doi-asserted-by":"publisher","first-page":"23","DOI":"10.1016\/j.jaci.2012.11.019","article-title":"Early-life environmental determinants of allergic diseases and the wider pandemic of inflammatory noncommunicable diseases","volume":"131","author":"Prescott","year":"2013","journal-title":"J Allergy Clin Immunol"},{"key":"B3","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.jaci.2017.05.010","article-title":"Environmental determinants of allergy and asthma in early life","volume":"140","author":"Burbank","year":"2017","journal-title":"J Allergy Clin Immunol"},{"key":"B4","doi-asserted-by":"publisher","first-page":"104","DOI":"10.1006\/enrs.1998.3834","article-title":"Blood levels of total and organic mercury in residents of the upper St. Lawrence river basin, Quebec: association with age, gender, and fish consumption","volume":"77","author":"Mahaffey","year":"1998","journal-title":"Environ Res"},{"key":"B5","doi-asserted-by":"publisher","first-page":"341","DOI":"10.1016\/j.envres.2005.01.006","article-title":"In vitro HgCl2 exposure of immune cells at different stages of maturation: effects on phenotype and function","volume":"98","author":"Silva","year":"2005","journal-title":"Environ Res"},{"key":"B6","doi-asserted-by":"publisher","first-page":"163","DOI":"10.1016\/S0300-483X(96)03486-5","article-title":"Immunomodulating effects after perinatal exposure to methylmercury in mice","volume":"114","author":"Thuvander","year":"1996","journal-title":"Toxicology"},{"key":"B7","doi-asserted-by":"publisher","first-page":"1932","DOI":"10.1289\/ehp.0900855","article-title":"Mercury induces an unopposed inflammatory response in human peripheral blood mononuclear cells in vitro","volume":"117","author":"Gardner","year":"2009","journal-title":"Environ Health Perspect"},{"key":"B8","doi-asserted-by":"publisher","first-page":"20","DOI":"10.1186\/1742-2094-7-20","article-title":"Mercury induces inflammatory mediator release from human mast cells","volume":"7","author":"Kempuraj","year":"2010","journal-title":"J Neuroinflammation"},{"key":"B9","doi-asserted-by":"publisher","first-page":"750","DOI":"10.4049\/jimmunol.140.3.750","article-title":"Autoreactive T cells in mercury-induced autoimmunity. 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