Uso de modelos predictivos y conceptuales para la evaluación ambiental y el análisis de la percepción de riesgo por uso de plaguicidas: Una opción para el manejo de riesgos en Chiapas

In the last decades the use of pesticides has increased, and with this, the risk that these substances represent for the environment and the human health. With several international agreements, Mexico has committed itself to reduce the risk that results from the use of pesticides; however, so far progress on the subject has not been satisfactory. On the one hand, the programs to evaluate and monitor environmental risk of pesticides have not been fully implemented, among other things, due to financial and technological limitations as well as lack of modeling approaches appropriate to the environmental conditions of tropical areas. On the other hand, risk communication programs have had limited impact. One of the reasons is that, like in other countries, there are great differences between the risk perception of those who communicate the risk and the population. The main objective of this doctoral thesis is to propose methods for risk assessment and the analysis of the risk perceptions on pesticides which facilitate the design of policies related to risk assessment and risk communication. To do so, two studies are presented. The fist one consists in an environmental risk assessment of pesticides. In this study, a modeling approach has been developed and used to calculate Predicted Environmental Concentrations (PEC) and risk probabilities for freshwater ecosystems in the humid tropics, appropriate in a context of scarce economic and technological resources. The second study is an analysis of the risk perception of different actors involved in the use and management of pesticides. In this second study similarities and differences between experts and lay people are explained from a social science perspective. In the conclusions of this thesis we present, on the one hand, a first advance in the performing of a modeling approach to predict environmental risks of pesticides, and, on the other hand, a conceptual model is proposed that explains the factors that influence the risk perception of experts and lay people about pesticides. Both modeling tools, which may be used independently, form the basis for the design of public policies and for new research on the topic of pesticide risk.