Understanding the potential health effects of pesticides is difficult due to the episodic nature of exposure and the lack of individual’s knowledge regarding their personal exposure. The ISA Cohort study in Costa Rica is a community-based cohort of 350 mothers and their now 5-7 year old children living in Matina County, Costa Rica, a banana growing region for the country. These individuals are exposed to a variety of different chemicals as used in agriculture, mainly banana production, vector control, and pasture, including mancozeb, chlorpyrifos, pyrimethanil, thiabendazole, cypermethrin, and 2,4-D. Exposure to these and other pesticides, as well as manganese (a component of mancozeb), has been measured through biological and environmental monitoring of the cohort for the past six years. To date, investigators have been funded to assess growth and neurobehavioral outcomes associated with pre- and post-natal exposure to these pesticides, oxidative stress, and respiratory and allergic outcomes in mothers and children. The ISA cohort provides critical information to assess the potential human health effects of pesticides as these same pesticides are used in the US as well as Costa Rica. This proposal will strengthen the ISA cohort for the long-term by: 1) creating a more consistent outreach program to inform the cohort members as well as their communities, civil society organizations, governmental organizations and private sector about study findings on a regular basis; 2) updating participant medical history including neurobehavioral and respiratory outcomes and collecting biological samples every two years; 3) establishing more complete data documentation to allow for easier collaboration and data sharing; 4) providing long term specimen storage in Costa Rica; and 5) enhancing understanding of pesticide exposure in the cohort and community through aggregation of available exposure data for cohort participants, validation of urinary biomarkers with environmental sampling, air monitoring of pesticides at primary schools situated in the study area, and statistical approaches to manage the complex exposure data. This proposal focuses on a community-engaged model to enhance long term follow-up by collecting and report data relevant to the community on a routine basis.