Remoción de plaguicidas de agua potable en comunidades rurales y periurbanas mediante el uso de bioaumentación en filtros lentos con retrolavado: aplicación en Costa Rica y Brasil

Water scarcity and pollution, including diffuse pesticide contamination, pose threats to human health, food security, and social development. Decentralized treatment strategies ensure safe access to water in hard-to-reach areas, especially in rural or peri-urban communities. However, these types of treatment systems must be low-cost, easy to operate, and maintain. In this context, conventional slow sand filters are a recognized option, but their cleaning and application in pesticide-contaminated water is limited. In this regard, the use of backwashable slow sand filters, developed by the Brazilian counterpart, is proposed, with simpler and more cost-effective cleaning operations. Bioaugmentation of the filters is also planned by adding specific inoculants for a pesticide of interest to both countries. Specifically, in Costa Rica, in cooperation with CICA-UCR, inoculants for three pesticides of interest with potential biodegradation will be developed using locally sourced soils. Diazinon, 2,4D, and atrazine have been identified. Laboratory-level flask tests will determine the inoculum with the greatest potential for use in pilot systems using slow backwashing filters and slow filters without backwashing (conventional) filters. A similar procedure will be followed in Brazil. In each country, the system will consist of two backwashing filters and two conventional filters, one of each type with the respective inoculum added. The filters will be
used to treat natural water enriched with the pesticide of interest. The filters will be in operation for at least nine months, cleaning by backwashing or scraping, as appropriate. During this process, in addition to general parameters of the raw and treated water (turbidity, coliforms, pH, etc.), the removal capacity of the pesticide of interest will be determined. Therefore, the effectiveness of each type of filter and the bioaugmentation process can be determined and compared. Furthermore, microbiological tests will be used to compare the different filters in terms of the development of the biological layer responsible for filtration (Schmutzdecke) and the type of microbial community present.

Determinar la capacidad de remoción de plaguicidas por medio de filtros lentos con retrolavado bioaugmentados.

Soluciones de ingeniería ambiental para el desarrollo.