Air pollution exposure and mammographic breast density in Tehran, Iran: a cross-sectional study.

"Declaration Ethics approval and consent to participateThe study was approved by the ethics committee of Tehran University of Medical Sciences (IR.TUMS.VCR.REC.1398.897), and all participants have signed an informed consent. Consent for publicationNot applicable. Availability of data and materialThe datasets used and analyzed during the current study are available on reasonable request from the corresponding author. Competing interestsThe authors declare that they have no competing interests. FundingThis study was funded by Institute for Environmental Research (IER) and by an academic research grant from the Deputy of Research of Tehran University of Medical Sciences (grant number: 98-3-259-45184). Authors’ contributionsBE contributed to the conception, design of the work, interpretation of data, and drafting of the manuscript. SA, RO, MSH contributed to the design of the work and substantively revised the manuscript. MMN contributed to the analysis and interpretation of data. KN, AA, MA, and LB contributed to the conception and acquisition of the data. MSH as a corresponding author contributed in all steps. All authors read and approved the final manuscript. They accepted their own contribution to this manuscript and accepted all responsibilities. AcknowledgementThe authors are grateful to Tehran Air Quality Control Company (TAQCC) for providing ambient air pollutants concentrations data. Also, the authors would like to thank Zohre Samadi, Mina Mahmoodi, and Afsaneh Teimoori, for their assistance in collecting data, which made this project possible. We would like to express our special thanks to Faezeh Izadpanah who helped us in extracting environmental data. Competing interests The authors declare that they have no competing interests."

"Funding This study was funded by Institute for Environmental Research (IER) and by an academic research grant from the Deputy of Research of Tehran University of Medical Sciences (grant number: 98-3-259-45184)."