title: Environmental and personal determinants of the uptake of disinfection by-products during swimming.
abstract: Trihalomethanes (THMs) in exhaled breath and trichloroacetic acid (TCAA) in urine are internal dose biomarkers of exposure to disinfection by-products (DBPs) in swimming pools.
  
  
  
  We assessed how these biomarkers reflect the levels of a battery of DBPs in pool water and trichloramine in air, and evaluated personal determinants.
  
  
  
  A total of 116 adults swam during 40min in a chlorinated indoor pool. We measured chloroform, bromodichloromethane, dibromochloromethane and bromoform in exhaled breath and TCAA in urine before and after swimming, trichloramine in air and several DBPs in water. Personal determinants included sex, age, body mass index (BMI), distance swum, energy expenditure, heart rate and 12 polymorphisms in GSTT1, GSTZ1 and CYP2E1 genes.
  
  
  
  Median level of exhaled total THMs and creatinine adjusted urine TCAA increased from 0.5 to 14.4µg/m(3) and from 2.5 to 5.8µmol/mol after swimming, respectively. The increase in exhaled brominated THMs was correlated with brominated THMs, haloacetic acids, haloacetonitriles, haloketones, chloramines, total organic carbon and total organic halogen in water and trichloramine in air. Such correlations were not detected for exhaled chloroform, total THMs or urine TCAA. Exhaled THM increased more in men, urine TCAA increased more in women, and both were affected by exercise intensity. Genetic variants were associated with differential increases in exposure biomarkers.
  
  
  
  Our findings suggest that, although affected by sex, physical activity and polymorphisms in key metabolizing enzymes, brominated THMs in exhaled breath could be used as a non-invasive DBP exposure biomarker in swimming pools with bromide-containing source waters. This warrants confirmation with new studies.
authors.affiliation: ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública, Barcelona, Spain.
authors.forename: Laia
authors.initials: L
authors.lastname: Font-Ribera
authors.affiliation: ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública, Barcelona, Spain.
authors.forename: Manolis
authors.initials: M
authors.lastname: Kogevinas
authors.affiliation: University Tübingen, Tübingen, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Schmalz
authors.affiliation: University Tübingen, Tübingen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Zwiener
authors.affiliation: Institute of Environmental Assessment and Water Research (IDÆA-CSIC), Barcelona, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Marco
authors.affiliation: Institute of Environmental Assessment and Water Research (IDÆA-CSIC), Barcelona, Spain.
authors.forename: Joan O
authors.initials: JO
authors.lastname: Grimalt
authors.affiliation: Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong, China.
authors.forename: Jiaqi
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong, China.
authors.forename: Xiangru
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Civil and Environmental Engineering, Stanford University, Palo Alto, CA, USA.
authors.forename: William
authors.initials: W
authors.lastname: Mitch
authors.affiliation: Human Genetics Fundation (HuGEF), Torino, Italy.
authors.forename: Rossana
authors.initials: R
authors.lastname: Critelli
authors.affiliation: Human Genetics Fundation (HuGEF), Torino, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Naccarati
authors.affiliation: Institute for Risk Assessment Sciences (IRAS), Utrecht, The Netherlands.
authors.forename: Dick
authors.initials: D
authors.lastname: Heederik
authors.affiliation: Institute for Risk Assessment Sciences (IRAS), Utrecht, The Netherlands.
authors.forename: Jack
authors.initials: J
authors.lastname: Spithoven
authors.affiliation: ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública, Barcelona, Spain.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Arjona
authors.affiliation: ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública, Barcelona, Spain.
authors.forename: Jeroen
authors.initials: J
authors.lastname: de Bont
authors.affiliation: ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública, Barcelona, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Gracia-Lavedan
authors.affiliation: ISGlobal, Center for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; IMIM (Hospital del Mar Medical Research Institute), Barcelona, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain; CIBER Epidemiología y Salud Pública, Barcelona, Spain. Electronic address: cvillanueva@creal.cat.
authors.forename: Cristina M
authors.initials: CM
authors.lastname: Villanueva
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism / Q000652:urine; D004202:Disinfectants / Q000378:metabolism* / Q000652:urine; D004203:Disinfection; D005260:Female; D006801:Humans; D008297:Male; D013030:Spain; D013550:Swimming; D013551:Swimming Pools; D014238:Trichloroacetic Acid / Q000652:urine*; D022882:Trihalomethanes / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism* / Q000652:urine; D055815:Young Adult
chemical_list: D015415:Biomarkers; D004202:Disinfectants; D022882:Trihalomethanes; D014874:Water Pollutants, Chemical; D014238:Trichloroacetic Acid
keywords: Biomarkers; DBPs; Disinfection by-products; Haloacetic acids; Internal dose; Swimming pools; THMs; Trihalomethanes