title: Medications as a potential source of exposure to phthalates in the U.S. population.
abstract: BACKGROUND
  Widespread human exposure to phthalates, some of which are developmental and reproductive toxicants in experimental animals, raises concerns about potential human health risks. Underappreciated sources of exposure include phthalates in the polymers coating some oral medications.
  
  
  OBJECTIVE
  The objective of this study was to evaluate whether users of phthalate-containing medications have higher urinary concentrations of phthalate metabolites than do nonusers.
  
  
  METHODS
  We used publically available files from the National Health and Nutrition Examination Survey for the years 1999-2004. For certain survey periods, participants were asked to recall use of prescription medication during the past 30 days, and for a subsample of individuals, the urinary concentrations of phthalate metabolites were measured. We a priori identified medications potentially containing phthalates as inactive ingredients and then compared the mean urinary concentration of phthalate metabolites between users and nonusers of those medications.
  
  
  RESULTS
  Of the 7,999 persons with information on urinary phthalate concentrations, 6 reported using mesalamine formulations, some of which may include dibutyl phthalate (DBP); the mean urinary concentration of monobutyl phthalate, the main DBP metabolite, among these mesalamine users was 50 times higher than the mean for nonusers (2,257 microg/L vs. 46 microg/L; p < 0.0001). Users of didanosine, omeprazole, and theophylline products, some of which may contain diethyl phthalate (DEP), had mean urinary concentrations of monoethyl phthalate, the main DEP metabolite, significantly higher than the mean for nonusers.
  
  
  CONCLUSIONS
  Select medications might be a source of high exposure to some phthalates, one of which, DBP, shows adverse developmental and reproductive effects in laboratory animals. These results raise concern about potential human health risks, specifically among vulnerable segments of the general population and particularly pregnant women and children.
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts 02115, USA. shernan@hsph.harvard.edu
authors.forename: Sonia
authors.initials: S
authors.lastname: Hernández-Díaz
authors.forename: Allen A
authors.initials: AA
authors.lastname: Mitchell
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Kelley
authors.forename: Antonia M
authors.initials: AM
authors.lastname: Calafat
authors.forename: Russ
authors.initials: R
authors.lastname: Hauser
mesh_terms: D000293:Adolescent; D000328:Adult; D003625:Data Collection; D016049:Didanosine / Q000008:administration & dosage / Q000032:analysis / Q000652:urine; D004781:Environmental Exposure / Q000032:analysis* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D019804:Mesalamine / Q000008:administration & dosage / Q000032:analysis / Q000652:urine; D008875:Middle Aged; D009853:Omeprazole / Q000008:administration & dosage / Q000032:analysis / Q000652:urine; D004364:Pharmaceutical Preparations / Q000008:administration & dosage* / Q000032:analysis*; D010795:Phthalic Acids / Q000008:administration & dosage / Q000032:analysis* / Q000652:urine; D011247:Pregnancy; D013806:Theophylline / Q000008:administration & dosage / Q000032:analysis / Q000652:urine; D055815:Young Adult
chemical_list: D004364:Pharmaceutical Preparations; D010795:Phthalic Acids; D019804:Mesalamine; C032279:phthalic acid; D013806:Theophylline; D016049:Didanosine; D009853:Omeprazole; C028577:monobutyl phthalate