title: Impact of air pollution on vitamin D deficiency and bone health in adolescents.
abstract: The association between air pollution and bone health was evaluated in adolescents in the city of Tehran. This study is essentially ecological. Vitamin D deficiency among adolescents has been reported at higher rates in polluted areas than in non-polluted areas. Additionally, residence in polluted areas is associated with lower levels of bone alkaline phosphatase.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the association between ambient air pollution and bone turnover in adolescents and to compare the prevalence of vitamin D deficiency between polluted and non-polluted areas of Tehran.
  
  
  METHODS
  This cross-sectional population-based study was conducted on 325 middle- and high-school students (both girls and boys) in Tehran in the winter. During the study period, detailed daily data on air pollution were obtained from archived data collected by Tehran Air Quality Control Company (AQCC). Serum levels of calcium, phosphorus, parathyroid hormone (PTH), bone-specific alkaline phosphatase, 25(OH) vitamin D, osteocalcin, cross-linked C-telopeptide (CTX), total protein, albumin, and creatinine were obtained from the study group.
  
  
  RESULTS
  Vitamin D deficiency was more prevalent in polluted areas than in non-polluted areas. After adjustment for age and sex, residence in the polluted area showed a statistically significant positive association with vitamin D deficiency and a statistically significant negative association with bone turnover. Interestingly, high calcium intake (>5000 mg/week) protects against the effects of air pollution on bone turnover.
  
  
  CONCLUSIONS
  Air pollution is a chief factor determining the amount of solar UVB that reaches the earth's surface. Thus, atmospheric pollution may play a significant independent role in the development of vitamin D deficiency.
authors.affiliation: Department of Community Medicine, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Elham
authors.initials: E
authors.lastname: Feizabad
authors.affiliation: Department of Medicine, Section of Endocrinology, Nutrition and Diabetes, Boston University School of Medicine, 85 E Newton St, Boston, MA, 02118, USA. arash_hsi@yahoo.com.|Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, 5th floor, Shariati Hospital, North Kargar, Tehran, 141142386, Iran. arash_hsi@yahoo.com.
authors.forename: Arash
authors.initials: A
authors.lastname: Hossein-Nezhad
authors.affiliation: Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, 5th floor, Shariati Hospital, North Kargar, Tehran, 141142386, Iran.
authors.forename: Zhila
authors.initials: Z
authors.lastname: Maghbooli
authors.affiliation: Endocrinology and Metabolism Clinical Sciences Institute, Tehran University of Medical Sciences, 5th floor, Shariati Hospital, North Kargar, Tehran, 141142386, Iran.
authors.forename: Majid
authors.initials: M
authors.lastname: Ramezani
authors.affiliation: Boston University School of Dental Medicine, 100 E Newton St, Boston, MA, 02118, USA.
authors.forename: Roxana
authors.initials: R
authors.lastname: Hashemian
authors.affiliation: Health Science Department, Worcester State University, Worcester, MA, 01602, USA.
authors.forename: Syamak
authors.initials: S
authors.lastname: Moattari
mesh_terms: D000293:Adolescent; D000397:Air Pollution / Q000009:adverse effects*; D000469:Alkaline Phosphatase / Q000097:blood; D001798:Blood Proteins / Q000032:analysis; D016723:Bone Remodeling; D002118:Calcium / Q000097:blood; D002136:Calcium, Dietary / Q000032:analysis; D024042:Collagen Type I / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D015675:Osteocalcin / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood; D010455:Peptides / Q000097:blood; D010758:Phosphorus / Q000097:blood; D015995:Prevalence; D013472:Sunlight; D014807:Vitamin D / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology / Q000209:etiology*
chemical_list: D001798:Blood Proteins; D002136:Calcium, Dietary; D024042:Collagen Type I; D010281:Parathyroid Hormone; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D014807:Vitamin D; D010758:Phosphorus; D000469:Alkaline Phosphatase; D002118:Calcium
keywords: AQI; Adolescents; Air pollution; Airborne particles; Bone health; Bone turnover; Calcium intake; NO2; PM2.5; Supplementation; UVB; Vitamin D