Childhood Neurodevelopment Improves Over Time after a Period of Heightened Pesticide Usage in Agricultural Communities

Abstract

Childhood Neurodevelopment Improves Over Time after a Period of Heightened Pesticide Usage in Agricultural CommunitiesAbstract Number:2812 Jose Ricardo Suarez*, Harvey Checkoway, Wael Al-Delaimy, and Sheila Gahagan Jose Ricardo Suarez* University of California San Diego, United States, E-mail Address: [email protected] Search for more papers by this author , Harvey Checkoway University of California San Diego, United States, E-mail Address: [email protected] Search for more papers by this author , Wael Al-Delaimy University of California San Diego, United States, E-mail Address: [email protected] Search for more papers by this author , and Sheila Gahagan University of California San Diego, United States, E-mail Address: [email protected] Search for more papers by this author AbstractINTRODUCTION: There is growing evidence that cholinesterase inhibitor pesticide exposures (i.e. organophosphates) affect neurodevelopment in children, primarily in areas affecting attention, inhibitory control and memory. However, it is unknown whether acute exposures to these pesticides can result in transient neurodevelopmental delays. We tested the hypothesis that a longer time after the end of a heightened period of pesticide usage (Mother’s day flower production) is associated with neurodevelopmental improvements in Ecuadorian children living in floricultural communities. Mother’s day is the second holiday with most flower sales.METHODS: The ESPINA study quantified AChE activity (EQM Testmate) of 307 children (age: 4-9 years, 52% male), and conducted neurodevelopment assessments in 5 domains (11 subtests) in children: attention/executive functioning, language, memory/learning, visuospatial processing, and sensorimotor (NEPSY-II). Examinations took place 52-88 days (mean: 73 days, standard deviation [SD]: 10.1) after Mother’s day: 7/13/2008 (exam dates: 7/10-8/15). Statistical models were adjusted for age, gender, race, height-for-age, floricultural worker cohabitation, home distance to flower plantations, maternal education and income.RESULTS: The range of standardized neurodevelopment scores was 5.9-10.7 units (SDs: 2.6-4.9); the mean AChE activity was 3.14 U/ml (SD: 0.49). We observed that children examined in the earlier period (7/10-7/30) had lower AChE activity (reflecting greater exposure, ß=-0.2 U/mL, p=0.01) than those examined later (8/10-8/15), after further adjustment for hemoglobin. Date of examination was also positively associated with Total Neurodevelopment (ß=0.02, p=0.01) and Attention/Executive Functioning domain (ß=0.03, p=0.01).CONCLUSIONS: Our findings suggest that neurodevelopmental alterations, particularly in Attention/Executive Functioning, improve as exposure to cholinesterase inhibitor pesticides decreases over time.