Suarez-Lopez_2019_Environ.Res_175_335

INTRODUCTION: Agricultural pesticide spray periods increase the pesticide exposure potential of children living nearby and growing evidence indicates that they may affect children's health. We examined the association of time following a heightened agricultural production period, the Mother's Day flower harvest (May), with children's blood pressure (BP). METHODS: We included cross-sectional information of 313 children ages 4-9 years in Ecuadorian agricultural communities (the ESPINA study). Examinations occurred during a period of low flower production, but within 63-100 days (mean=81.5, SD=10.9) following the Mother's Day harvest. BP was measured twice using a pediatric sphygmomanometer and BP percentiles appropriate for age, gender and height were calculated. RESULTS: Participants were 51% male, 1.6% hypertensive and 7.7% had elevated BP. The mean (SD) BP percentiles were: systolic: 51.7 (23.9); diastolic: 33.3 (20.3). There was an inverse relationship between of time after the spray season with percentiles of systolic (difference [beta] per 10.9 days after the harvest: -4.3 [95%CI: -6.9, -1.7]) and diastolic BP (beta: -7.5 [-9.6, -5.4]) after adjusting for race, heart rate and BMI-for-age z-score. A curvilinear association with diastolic BP was observed. For every 10.9 days that a child was examined sooner after the harvest, the OR of elevated BP/hypertension doubled (OR: 2.0, 95% CI: 1.3, 3.1). Time after the harvest was positively associated with acetylcholinesterase. CONCLUSIONS: Children examined sooner after a heightened pesticide spray period had higher blood pressure and pesticide exposure markers than children examined later. Further studies with multiple exposure-outcome measures across pesticide spray periods are needed.