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Your Environment. Your Health.


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Principal Investigator: Suarez, Jose Ricardo
Institute Receiving Award University Of California, San Diego
Location La Jolla, CA
Grant Number R01ES025792
Funding Organization National Institute of Environmental Health Sciences
Award Funding Period 01 Apr 2016 to 28 Feb 2027
DESCRIPTION (provided by applicant): Today, 20% of adolescents and 26% of young adults have a diagnosable internalizing (e.g. anxiety, depression) or externalizing problem (e.g. impulsivity, aggression, conduct disorders). Neurodevelopmental disabilities and mental health disorders in adolescents and young adults have increased over the last two decades worldwide, and environmental contaminants may explain a part of this increase. The most used insecticides worldwide include organophosphates (OPs: inhibitors of acetylcholinesterase (AChE)), pyrethroids and neonicotinoids. Toxicological and epidemiological evidence links OP exposure with altered neurocognitive performance. Additionally, a small number of studies have described associations with internalizing symptoms and some externalizing behaviors (i.e. low inhibitory control). It is plausible neonicotinoids may also affect brain processes as they share some toxicological mechanisms like OPs and emerging findings indicate pyrethroids may affect brain processes and neurobehavior. Further, emerging studies suggest that pesticides may transiently affect cognitive performance and mood. Assessing transient health outcomes is complex, which has led to limited knowledge on this field. We propose a renewal of our 2016 study of adolescents and young adults (ages 18-23 years in 2022, n≈554) and builds on the planned 2022 follow-up exam of the NIH-funded Study of Secondary Pesticide Exposures among Children and Adolescents (ESPINA). The proposed study incorporates a novel mobile health assessment tool to evaluate the real-world neurotoxic effects of pesticides. ESPINA is a study established in 2008 of participants residing in Pedro Moncayo, Ecuador, a county with one of the highest concentrations of flower plantations in the Americas. Leveraging our smartphone-based ecological momentary cognitive testing (EMCT) platform, we will assess whether recurring and seasonal pesticide exposures in adolescence and young adulthood affect cognition and mental health. Using a burst sampling design 5 times/year for 2 years during high- and low-pesticide spray seasons, we will test the hypotheses: 1) pesticide spray seasons are associated with cyclical alterations in internalizing symptoms, externalizing behaviors, and cognitive performance assessed using EMCT; 2) pesticide exposures (AChE inhibition and OP and pyrethroid urinary pesticide metabolites) assessed during 5 agricultural periods are related to elevated depressive and externalizing symptoms, and decreased cognitive performance assessed using EMCT; 3) Urinary pesticide metabolites (OP, neonicotinoids, pyrethroids) are associated with increased mental health symptoms from 2016 to 2022 when all participants were adolescents, and whether age, sex and COVID-19-related factors (e.g., exposure; psychosocial stressors) modify the associations between environmental exposures and mental health. Identifying cognitive and mental health sequelae related to agricultural pesticide spray seasons on people living in agricultural settings will advance this understudied field of research and has significant implications for public health.
Science Code(s)/Area of Science(s) Primary: 61 - Neurodevelopmental
Secondary: -
Publications See publications associated with this Grant.
Program Officer Lindsey Martin
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