Remoción de clorotalonil y sus metabolitos en agua para consumo humano en zonas rurales utilizando carbón activado

Several drinking water sources in the Santa Rosa and Cipreses de Oreamuno
districts of Cartago reported contamination with chlorothalonil and its metabolites
since 2022, affecting nearly 10,000 people with concentrations up to 200 times the
value allowed in the legislation. Chlorothalonil is a potential carcinogen. The
mentioned sources are in charge of the Associations managing the Aqueduct and
Sewer Systems (ASADAS) of both districts, whose personnel lack the experience
and technical capacity to solve this problem. Therefore, the Institute of Aqueducts
and Sewers (AyA), as the governing body, must provide a solution to the problem.
To date, AyA has had to supply the affected communities with drinking water
through tanker trucks; however, this option represents a high expense for the
institution. Alternatively, treatment systems such as membrane filtration or the use of
activated carbon can be found on the market. In either case, it is necessary to have
specialized knowledge to choose the best option and its subsequent design and
implementation. At the country level, the use of activated carbon by AyA for the
removal of odor, color and in some cases hydrocarbons has been demonstrated.
However, there is not enough experience on the part of the AyA and the ASADAS
with the design of filters to treat micropollutants (e.g., pesticides). Therefore, it is
necessary to generate a protocol on the steps to follow, from laboratory-scale
studies, which involve batch and column adsorption tests, to the subsequent scaling
and environmental design of a treatment system. In addition, these previous tests
will allow us to determine which type of activated carbon on the market (bituminous
or coconut) is the most appropriate for the removal of chlorothalonil and its
metabolites. Currently, the proposing group uses this type of protocol for the
adsorption of contaminants (e.g. arsenic), but it is necessary to adjust it to the
pesticide in question and activated carbon. For these tests, water from one of the
affected springs will be used, thus being able to generate as a product a pre-design
of the system to be applied in said community. Thus, two specific products would be
generated: a protocol for the environmental design of activated carbon filters to be
transferred to AyA as the governing body and the pre-design for the source of a
selected community. At the same time, it is intended to train the personnel of the
ASADAS in the area and the nearby municipalities (Oreamuno and Paraíso) in terms
of the possible ways to remove this type of substances from drinking water,
instructing them in terms of the origin of the contaminant, behavior in the
environment, danger and the different treatment options available, emphasizing the
use of activated carbon as the most promising alternative. In addition, the
aforementioned protocol and the results of the experimental part of this project will
be included, so that the staff knows that this type of systems involve a laborious,
expensive experimental part that must be carried out by specialized personnel, in
other words that There is no miracle solution. Finally, this research will be an
important tool in the elimination of pesticides from drinking water, consolidating TEC
as an expert in this field, to, either through paid employment or through future
extension projects, generate a possible solution to contamination of water with
pesticides.

1. Escuela de Química: Soluciones de ingeniería ambiental para el desarrollo: Soluciones científicas, tecnológicas
e innovadoras en el campo de la prevención, mitigación, adaptación, control y corrección de problemas
ambientales y procesos productivos.