Nano fraction of pesticide induces genotoxicity and oxidative stress-dependent reticulum stress.

The implementation of nanotechnology in different sectors has generated expectations as a new source of use due to the novel characteristics that it will bring. Particularly, nano pesticides promise to be more sustainable and less harmful to the ecosystem and human health; however, most studies continue to focus on their efficacy in the field, leaving aside the effect on humans. This project aimed to evaluate the genotoxic effect of a nano-encapsulated pesticide on bronchial epithelial cells (NL-20) in vitro and elucidate the mechanism through which they induce damage. The nano fraction (NF) of the pesticide Karate Zeon® 5 CS was characterized and isolated, and the uptake into the cell and the changes induced in the cellular ultrastructure were evaluated. In addition, the primary markers of oxidative stress, reticulum stress, and genotoxicity were assessed using the micronucleus test. A 700 nm fraction with a Z potential of -40 mV was obtained, whose main component is polyurea formaldehyde; this allows the capsules to enter the cell through macropinocytosis and clathrin-mediated endocytosis. Inside, they induce oxidative stress activating a reticulum stress response via the BIP protein and the IRE-1 sensor, triggering an inflammatory response. Likewise, stress reduces cell proliferation, increasing genotoxic damage through micronuclei; however, this damage is mainly induced by direct contact of the capsules with the nucleus. This pioneering study uses a nanometric encapsulated commercial pesticide to evaluate the molecular mechanism of induced damage. It makes it the first step in analyzing whether these substances represent a contaminant or an emerging solution.

Genotoxic evaluation of common commercial pesticides in human peripheral blood lymphocytes.

This study aims to evaluate the genotoxic potential of four commercial pesticides with diverse health categorizations by different world associations currently in use. We tested the fungicide mancozeb and the insecticides pirimicarb, monocrotophos and permethrin. The research was done with in vitro human peripheral blood lymphocytes using the DNA single gel electrophoresis assay and the cytokinesis-block micronucleus (MN) test, where we analysed common parameters such as the tail moment and the frequency of MN formation. We also measured other parameters like frequency of nucleoplasmic bridges, nuclear buds, apoptosis and necrosis with the MN test. Each pesticide induced significant differences in all of these parameters when compared with the negative control and showed different behaviours in the concentration-dependent response. This could be attributed to their genotoxic potential where mancozeb and monocrotophos induced the highest genetic damage, permethrin caused mainly cell death and pirimicarb had the least impact upon cells. This research provides valuable data about the harmful effects of these pesticides on human cells and may be an important contribution in the construction of a unique international classification of health and to reinforce the use of genotoxic analyses to regulate the use of pesticides.