Toxicological Aspects of Pesticides

Abstract

Over 3 million tons of pesticide active ingredients were used worldwide in 2016, about 60% in China. Pesticides are primarily used in agriculture, but also to control disease insect vectors, domestic pests, and home gardening, among other uses. The general population is exposed to pesticides mainly through the consumption of treated food. Dietary intake assessment can be performed for specific population groups, such as toddlers, teenagers, and seniors, considering chronic and/or acute exposure, and may be combined with residential and water exposure. Most dietary exposure assessments conducted worldwide indicate low health risks to consumers. The main exposure route of pesticides for the occupational population is through skin contact, which occurs mainly from spilling pesticides and drift while mixing or applying pesticides. Epidemiological studies have shown association between pesticide exposure and various diseases, mainly cancer, although there is a lack of consensus among scientists on the link between pesticide exposure and cancer. The environment can also be affected by pesticide use, as the products may move off-site via spray drift, leaching, and runoff and affect non-target aquatic and terrestrial organisms. Pesticides with high water solubility and mobility have the potential to reach groundwater, and those with low mobility have a tendency to remain in soil/sediments, but they can reach water systems through superficial runoff. Exposure of the biota to pesticides at sublethal levels during the embryonic period may interfere with the development and survival of embryos and hatchling, with a potential impact on population survival, biodiversity, and ecological equilibrium.