2,4‐D dissipation in field soils after applications of 2,4‐D dimethylamine salt and 2,4‐D 2‐ethylhexyl ester

Abstract

Abstract-2,4-Dichlorophenoxyacetic acid (2,4-D) was first registered in 1947 as an agricultural herbicide, and it is still the most widely used herbicide worldwide. End-use products, however, are generally formulated as inorganic or amine salts, or as esters. Because of the various forms available, there was concern that by testing only one form, the environmental profile generated might be insufficient to represent all forms. Therefore, as part of the 2,4-D reregistration process in the U.S., 30 soil dissipation studies were conducted with 2,4-D dimethylamine salt and 2,4-D 2-ethylhexyl ester over a 2-year period. Trials were located in seven states and included four cropping practices and bare soil. The results, averaged over all conditions, showed equivalent rates of 2,4-D dissipation in soil when applied as either the amine salt or ester forms. These results also confirm data from earlier field studies in Canada and Washington state showing equivalent 2,4-D dissipation in soil from applications of isooctyl ester, dimethylamine salt, and mixed amine salt forms. The data from the current and former studies show that ester and amine forms have little effect on the rate of dissipation of 2,4-D per se because they are converted rapidly to the same anionic form.

A wind-powered BDD electrochemical oxidation process for the removal of herbicides

“…Pesticides exhibit bio-recalcitrant properties and high toxicity and persist in the environment (Wilson et al, 1997). This fact has attracted the interest of the scientific community to develop effective processes to eliminate them from the environment (Fenner et al, 2013;Huang et al, 2011).…”

Degradation of 2,4-Dichlorophenoxyacetic Acid (2,4-D) by Novel Photocatalytic Material of Tourmaline-Coated TiO2 Nanoparticles: Kinetic Study and Model

“…2,4-D and its salts as well as esters, are efficient, highly selective herbicides [8] and plant growth regulators [9]. It was initially registered in 1947 and, is still one of the most used herbicides in the world [10]. However, it may enter water bodies after usage in farmland [11], or for improper disposal [12], resulting in its broad residues in environment [13,14].…”

Dissipation and residue of 2,4-D isooctyl ester in wheat and soil

“…Fu and colleagues' (2009) research showed that the halflife of 2,4-D in natural agriculture soils of Fuzhou was 4.6 days and He et al (2010) indicated that the half-lives of 2,4-D-dimethylammonium in soil were 2-3 days. Another paper also studied the 2,4-D dissipation in field soils after application of 2,4-D dimethylamine salt and 2,4-D ethylhexyl ester, the results showed that the half-lives were 4-5 days, and either the amine salt or ester forms had the equivalent dissipation rates (Wilson et al 1997). That is to say, amine and ester forms have little effect on the dissipation of 2,4-D in soil for they are converted rapidly to the same anionic form.…”