Variability of urinary pesticide metabolite concentrations during pregnancy in the MARBLES Study

• Type of Material: Article
• Authors: Jacqueline Barkoski, University of California Davis; Deborah Bennett, University of California Davis; Daniel Tancredi, University of California Davis; Dana Boyd Barr, Emory University; William Elms, University of California Davis; Irva Hertz-Picciotto, University of California Davis
• Language: English
• Date: 2018-08-01
• Publisher: Elsevier
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2018 Elsevier Inc.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.envres.2018.05.002
• Title of Journal or Parent Work: Environmental Research
• ISSN: 0013-9351
• Volume: 165
• Start Page: 400
• End Page: 409
• Grant/Funding Information: The project described was supported by NIEHS grants R01ES020392, R24ES028533, P30ES023513, and P01ES11269, U.S EPA STAR grant 83543201, NICHD grant U54HD079125, Autism Science Foundation Pre-doctoral Training Fellowship, and the UC Davis MIND Institute.
• Keywords: TEMPORAL VARIABILITY; Exposure; Pesticides; Environmental Sciences; PYRETHROID INSECTICIDES; Longitudinal; Life Sciences & Biomedicine; Environmental Sciences & Ecology; NEURODEVELOPMENT; NORTH-CAROLINA; INNER-CITY CHILDREN; PRENATAL EXPOSURE; Variability; ORGANOPHOSPHORUS PESTICIDES; COHORT; Pregnancy; Public, Environmental & Occupational Health; Science & Technology; MEXICAN-AMERICAN CHILDREN; AUTISM SPECTRUM DISORDERS
• Research Categories: Health Sciences, Public Health; Health Sciences, Obstetrics and Gynecology

Abstract

Background: Variability of short-lived urinary pesticide metabolites during pregnancy raises challenges for exposure assessment. Objectives: For urinary metabolite concentrations 3-phenoxybenzoic acid (3-PBA) and 3,5,6-trichloro-2-pyridinol (TCPy), we assessed: (1) temporal variability; (2) variation of two urine specimens within a trimester; (3) reliability for pesticide concentrations from a single urine specimen to classify participants into exposure tertiles; and (4) seasonal or year variations. Methods: Pregnant mothers (N = 166) in the MARBLES (Markers of Autism Risk in Babies-Learning Early Signs) Study provided urine specimens (n = 528). First morning void (FMV), pooled, and 24-h specimens were analyzed for 3-PBA and TCPy. For 9 mothers (n = 88 specimens), each urine specimen was analyzed separately (not pooled) to estimate within- and between-person variance components expressed as intraclass correlation coefficients (ICC). Pesticide concentrations from two specimens within a trimester were also assessed using ICC's. Agreement for exposure classifications was assessed with weighted Cohen's kappa statistics. Longitudinal mixed effect models were used to assess seasonal or year variations. Results: Urinary pesticide metabolites were detected in ≥ 93% of specimens analyzed. The highest ICC from repeated individual specimens was from specific gravity-corrected FMV specimens for 3-PBA (ICC=0.13). Despite high within-person variability, the median concentrations did not differ across trimesters. Concentrations from pooled specimens had substantial agreement predicting exposure categories for TCPy (K = 0.67, 95% CI (0.59, 0.76)) and moderate agreement for 3-PBA (K = 0.59, 95% CI (0.49, 0.69)). TCPy concentrations significantly decreased from 2007 to 2014. Conclusions: Pooled specimens may improve exposure classification and reduce laboratory costs for compounds with short biological half-lives in epidemiological studies.