TY - JOUR
T1 - Temporal variability in urinary excretion of bisphenol A and seven other phenols in spot, morning, and 24-h urine samples
AU - Lassen, Tina Harmer
AU - Frederiksen, Hanne
AU - Jensen, Tina Kold
AU - Petersen, Jørgen Holm
AU - Main, Katharina M.
AU - Skakkebæk, Niels E.
AU - Jørgensen, Niels
AU - Kranich, Selma Kløve
AU - Andersson, Anna Maria
PY - 2013
Y1 - 2013
N2 - Human exposure to modern non-persistent chemicals is difficult to ascertain in epidemiological studies as exposure patterns and excretion rates may show temporal and diurnal variations. The aim of this study was to assess the temporal variability in repeated measurements of urinary excretion of bisphenol A (BPA) and seven other phenols. All analytes were determined using TurboFlow-LC-MS/MS. Two spot, three first morning and three 24-h urine samples were collected from 33 young Danish men over a three months period. Temporal variability was estimated by means of intraclass correlation coefficients (ICCs). More than 70% of the urine samples had detectable levels of BPA, triclosan (TCS), benzophenone-3 (BP-3) and sum of 2,4-dichlorophenol and 2,5-dichlorophenol (σDCP). We found low to moderate ICCs for BPA (0.10-0.42) and σDCP (0.39-0.72), whereas the ICCs for BP-3 (0.69-0.80) and TCS (0.55-0.90) were higher. The ICCs were highest for the two spot urine samples, which were collected approximately 4 days apart, compared with the 24-h urine samples and the first morning urine samples, which were collected approximately 40 days apart. A consequence of the considerable variability in urinary excretion of BPA may be misclassification of individual BPA exposure level in epidemiological studies, which may lead to attenuation of the association between BPA and outcomes. Our data do not support that collection of 24-h samples will improve individual exposure assessment for any of the analysed phenols.
AB - Human exposure to modern non-persistent chemicals is difficult to ascertain in epidemiological studies as exposure patterns and excretion rates may show temporal and diurnal variations. The aim of this study was to assess the temporal variability in repeated measurements of urinary excretion of bisphenol A (BPA) and seven other phenols. All analytes were determined using TurboFlow-LC-MS/MS. Two spot, three first morning and three 24-h urine samples were collected from 33 young Danish men over a three months period. Temporal variability was estimated by means of intraclass correlation coefficients (ICCs). More than 70% of the urine samples had detectable levels of BPA, triclosan (TCS), benzophenone-3 (BP-3) and sum of 2,4-dichlorophenol and 2,5-dichlorophenol (σDCP). We found low to moderate ICCs for BPA (0.10-0.42) and σDCP (0.39-0.72), whereas the ICCs for BP-3 (0.69-0.80) and TCS (0.55-0.90) were higher. The ICCs were highest for the two spot urine samples, which were collected approximately 4 days apart, compared with the 24-h urine samples and the first morning urine samples, which were collected approximately 40 days apart. A consequence of the considerable variability in urinary excretion of BPA may be misclassification of individual BPA exposure level in epidemiological studies, which may lead to attenuation of the association between BPA and outcomes. Our data do not support that collection of 24-h samples will improve individual exposure assessment for any of the analysed phenols.
KW - Benzophenone-3
KW - Bisphenol A
KW - Epidemiology
KW - Temporal variability
KW - Triclosan
UR - http://www.scopus.com/inward/record.url?scp=84885851502&partnerID=8YFLogxK
U2 - 10.1016/j.envres.2013.07.001
DO - 10.1016/j.envres.2013.07.001
M3 - Journal article
C2 - 23932849
AN - SCOPUS:84885851502
SN - 0013-9351
VL - 126
SP - 164
EP - 170
JO - Environmental Research
JF - Environmental Research
ER -