Pesticide Chemistry in the Environment

Abstract

The use of pesticides has resulted in increased crop production but also raised concerns about potential adverse effects on the environment. The knowledge of pesticide environmental behavior, like soil adsorption, leaching, and volatility, is necessary to asses the risk to the environment and humans. The properties of pesticides, such as herbicides, insecticides, and fungicides, combined with the amount applied, determine how many pesticides can be transported along each route into the environment. Among insecticides, the monitoring of organochlorine pesticides (OCP) with low water solubility and high environmental persistence is highly recommended. Field studies determined that soil characteristics, topographic position, and land uses influence in OCP accumulation. The accumulation pattern represent a dynamic balance between deposition and erosion in association with wind‐induced circulation, tillage management practices, and effects by natural processes, such as rainfall and flooding periods, according to different soils. Moreover, the use of pesticides on agricultural land may have a negative effect on nearby aquatic ecosystems. This effect is determined by the specific chemicals used, the place and methods of application of the chemicals, and the various mechanisms available for transporting compounds to the waterbodies, with soil erosion being a major pathway. Hydrophobicity and persistence are the main properties of pesticides that control their accumulation in sediment and aquatic biota. Thus, this fact confirms the current necessity of OCP monitoring in natural areas.

Control capacity of the LPSc 1067 strain of Beauveria bassiana (Ascomycota: Hypocreales) on different species of grasshoppers (Orthoptera: Acrididae: Melanoplinae), agricultural pests in Argentina

“…Since the mid-nineteenth century, these insects have been reported in several regions of Argentina, following the progressive agricultural development of the country. So far, synthetic insecticides are still the only alternative against grasshoppers, regardless of negative environmental consequences (5).…”

Lindane removal induction by Streptomyces sp. M7

“…Indeed, lindane is a persistent pesticide, with a half-life reported to be from 4 to 6 weeks to 120 days (BINTEIN and DEVILLERS 1996), or 260 days to 2 years (JOHRI et al 1996), depending on the method of application and the environmental conditions. Although it has banned in many countries because of its toxicity and recalcitrant nature, numerous sites still remain contaminated throughout the world and newer polluted sites are being generated because of its continued use in other countries even today (NAWAB et al 2003, MIGLIORANZA et al 2005. Thus, it is of considerable interest to develop methods for the detoxification of lindane at sites of purposeful application and accumulation and/or accidental spillage.…”