TY - JOUR
T1 - Maternal prenatal and child organophosphate pesticide exposures and children's autonomic function
AU - Quirós-Alcalá, Lesliam
AU - Alkon, Abbey D.
AU - Boyce, W. Thomas
AU - Lippert, Suzanne
AU - Davis, Nicole V.
AU - Bradman, Asa
AU - Barr, Dana Boyd
AU - Eskenazi, Brenda
N1 - Funding Information:
This work was supported by grants from EPA ( RD 83171001 , Science to Achieve Results-STAR- Graduate Fellowship Program F5D30812) and NIEHS ( PO1ES009605 ). Contents do not necessarily represent the official views of funders. We thank our staff and community partners for helping with recruitment efforts, our study participants, our field staff for data collection, the CDC Pesticide Toxicology Laboratory staff for urine sample analysis, Dr. Kim Harley for overseeing ANS and OP pesticide data collection, Katherine Kogut for overseeing ANS data collection and conducting QA/QC of the ANS data, Drs. Jonathan Chevrier and Alan Hubbard for statistical assistance, and Drs. Katharine Hammond and Mark Nicas for editorial comments.
PY - 2011/10
Y1 - 2011/10
N2 - Background: Organophosphate pesticides (OP), because of their effects on cholinergic fibers, may interfere with the functions of the autonomic nervous system (ANS). We conducted a study to assess the relation of in utero and child OP pesticide exposures and children's autonomic nervous system (ANS) dysregulation under resting and challenge conditions. We hypothesized that children with high OP levels would show parasympathetic activation and no sympathetic activation during rest and concomitant parasympathetic and sympathetic activation during challenging conditions. Methods: OP exposures were assessed by measuring urinary dialkylphosphate metabolites (DAPs, total diethyls-DEs, and total dimethyls-DMs) in maternal and children's spot urine samples. ANS regulation was examined in relation to maternal and child DAPs in 149 children at 6 months and 1 year, 97 at 3 1/2 years and 274 at 5 years. We assessed resting and reactivity (i.e., challenge minus rest) measures using heart rate (HR), respiratory sinus arrhythmia (RSA), and preejection period (PEP) during the administration of a standardized protocol. Cross-sectional (at each age) and longitudinal regression models were conducted to assess OP and ANS associations. To estimate cumulative exposure at 5 years, we used an area-under-the-concentration-time-curve (AUC) methodology. We also evaluated whether children with consistently high versus low DAP concentrations had significantly different mean ANS scores at 5 years. Results: Child DMs and DAPs were significantly negatively associated with resting RSA at 6 months and maternal DMs and child DEs were significantly positively associated with resting PEP at 1 year. No associations with resting were observed in 3 1/2- or 5-year-old children nor with reactivity at any age. There was no significant relationship between the reactivity profiles and maternal or child DAPs. Cumulative maternal total DEs were associated with low HR (-3.19. bpm decrease; 95% CI: -6.29 to -0.09, p= 0.04) only at 5 years. In addition, there were no significant differences in ANS measures for 5-year-olds with consistently high versus low DAPs. Conclusion: Although we observe some evidence of ANS dysregulation in infancy, we report no consistent associations of maternal and child OP pesticide exposure, as measured by urinary DAPs, on children's ANS (HR, RSA, and PEP) regulation during resting and challenging conditions up to age 5 years.
AB - Background: Organophosphate pesticides (OP), because of their effects on cholinergic fibers, may interfere with the functions of the autonomic nervous system (ANS). We conducted a study to assess the relation of in utero and child OP pesticide exposures and children's autonomic nervous system (ANS) dysregulation under resting and challenge conditions. We hypothesized that children with high OP levels would show parasympathetic activation and no sympathetic activation during rest and concomitant parasympathetic and sympathetic activation during challenging conditions. Methods: OP exposures were assessed by measuring urinary dialkylphosphate metabolites (DAPs, total diethyls-DEs, and total dimethyls-DMs) in maternal and children's spot urine samples. ANS regulation was examined in relation to maternal and child DAPs in 149 children at 6 months and 1 year, 97 at 3 1/2 years and 274 at 5 years. We assessed resting and reactivity (i.e., challenge minus rest) measures using heart rate (HR), respiratory sinus arrhythmia (RSA), and preejection period (PEP) during the administration of a standardized protocol. Cross-sectional (at each age) and longitudinal regression models were conducted to assess OP and ANS associations. To estimate cumulative exposure at 5 years, we used an area-under-the-concentration-time-curve (AUC) methodology. We also evaluated whether children with consistently high versus low DAP concentrations had significantly different mean ANS scores at 5 years. Results: Child DMs and DAPs were significantly negatively associated with resting RSA at 6 months and maternal DMs and child DEs were significantly positively associated with resting PEP at 1 year. No associations with resting were observed in 3 1/2- or 5-year-old children nor with reactivity at any age. There was no significant relationship between the reactivity profiles and maternal or child DAPs. Cumulative maternal total DEs were associated with low HR (-3.19. bpm decrease; 95% CI: -6.29 to -0.09, p= 0.04) only at 5 years. In addition, there were no significant differences in ANS measures for 5-year-olds with consistently high versus low DAPs. Conclusion: Although we observe some evidence of ANS dysregulation in infancy, we report no consistent associations of maternal and child OP pesticide exposure, as measured by urinary DAPs, on children's ANS (HR, RSA, and PEP) regulation during resting and challenging conditions up to age 5 years.
KW - Autonomic nervous system (ANS)
KW - Children
KW - Heart rate
KW - In utero
KW - Neurodevelopment
KW - Organophosphates
KW - Pesticides
KW - Preejection period (PEP)
KW - Respiratory sinus arrhythmia (RSA)
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U2 - 10.1016/j.neuro.2011.05.017
DO - 10.1016/j.neuro.2011.05.017
M3 - Article
C2 - 21741403
AN - SCOPUS:80955157070
SN - 0161-813X
VL - 32
SP - 646
EP - 655
JO - NeuroToxicology
JF - NeuroToxicology
IS - 5
ER -