A Stochastic Simulation Procedure for Selecting Herbicides with Minimum Environmental Impact

Abstract

A mathematical environmental transport model of roadside applied herbicides at the site scale (∼100 m) was stochastically applied using a Monte-Carlo technique to simulate the concentrations of 33 herbicides in stormwater runoff. Field surveys, laboratory sorption data, and literature data were used to generate probability distribution functions for model input parameters to allow extrapolation of the model to the regional scale. Predicted concentrations were compared to EPA acute toxicity end points for aquatic organisms to determine the frequency of potentially toxic outcomes. Results are presented for three geographical regions in California and two highway geometries. For a given herbicide, frequencies of potential toxicity (FPTs) varied by as much as 36% between region and highway type. Of 33 herbicides modeled, 16 exhibit average FPTs greater than 50% at the maximum herbicide application rate, while 20 exhibit average FPTs less than 50% at the minimum herbicide application rate. Based on these FPTs and current usage statistics, selected herbicides were determined to be more environmentally acceptable than others in terms of acute toxicity and other documented environmental effects. This analysis creates a decision support system that can be used to evaluate the relative water quality impacts of varied herbicide application practices.

Investigations on the Degradation of Triazine Herbicides in Water by Photo-Fenton Process

“…Pesticides are xenobiotic, toxic and non-biodegradable and can cause serious problems to human health and environment [4]- [6]. Herbicides constitute the principal class of pesticides especially used in agriculture to protect the crops plant against weeds.…”

The Effect of Crop Rotation on Pesticide Leaching in a Regional Pesticide Risk Assessment

“…Distribution Function. Several model input parameters, characterized by different distribution functions (26), are combined during the simulation to produce a large amount of data (annual solute and percolation values). In a probabilistic approach, data distribution functions can be fitted to simulation output depending on the aim of the study and following different hierarchical levels (polygon, rotation, year, simulation).…”

Kinetic and mechanistic investigations of mesotrione degradation in aqueous medium by Fenton process

“…However, concerns about the potential impacts of pesticides on human health have arisen because the extensive use of these substances leads to their presence, together with their metabolites, in surface wastewaters from agricultural activities and in drinking waters. Herbicides may pose an environmental threat because they are designed to have a specific physiological effect on humans or animals since some of them are known to be xenobiotic, mutagenic, carcinogenic or teratogenic [7][8][9][10]. Their elimination from wastewater effluents is now the subject of considerable concern of environmental remediation and has attracted many researchers in recent years [9,10].…”