In the broadest sense, the application of pesticides involves the transfer of a toxicant from the manufacturer to the target organism. This is the dose transfer process, which can be broken down into several major events. However, difficulties at any step can result in a loss of biological activity, excessive environmental contamination or both. The dose transfer process is a roadmap for the ev...

The expansion of dryeration may impose a further problem for insect control with protectants – the high grain temperatures during insecticide spraying. To assess the impact of this procedure on insecticide activity, maize grains at different temperatures (25, 30, 35, 40 and 45 °C) were sprayed with pirimiphos-methyl. Residue analyses were carried out every 30 days and insecticide biological act...

Indoor residual spraying—spraying insecticide inside houses to kill mosquitoes—is an important method for controlling malaria vectors in sub-Saharan Africa. We propose a mathematical model for both regular and non-fixed spraying, using impulsive differential equations. First, we determine the stability properties of the nonimpulsive system. Next, we derive minimal effective spraying intervals a...

This paper exploits variations in aerial spraying across time and space in Colombia and employs a panel of individual health records in order to study the causal effects of the aerial spraying of herbicides (glyphosate) on short-term health-related outcomes. Our results show that exposure to the herbicide used in aerial spraying campaigns increases the number of medical consultations related to...

The ability to predict the effects of toxicants in organisms with reasonable accuracy depends to a great extent on the toxico-kinetic models used to describe such effects. Toxic effects of organic chemicals and heavy metals have been described adequately using a hyperbolic model that considers the concentration of the toxicant and the time of exposure only. Such a model relies on the median tim...