Article

Chromatographic separation of chlorophenoxy acid herbicides and their radiolytic degradation products in water samples.

Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.
Water Research (Impact Factor: 4.66). 06/2004; 38(14-15):3259-64. DOI: 10.1016/j.watres.2004.03.032
Source: PubMed

ABSTRACT HPLC procedure for simultaneous determination of chlorophenoxy acid herbicides and their radiolytic degradation products in waters is described with the use of octadecylsilica column and spectrophotometric detection at 280 nm. The satisfactory separation was achieved with a mobile phase of pH 2.5 consisting of 43.7 mM acetic acid with 40% (v/v) acetonitrile. Limit of detection values for herbicides and phenol derivatives were in the range of 19-41 microg/l and 10-60 microg/l, respectively. The developed method was applied for monitoring the effectiveness of radiolytic degradation of herbicides. Studies of products of gamma-radiolysis of 2,4-dichlorophenol have shown that the efficiency of this process is affected by the presence of naturally occurring scavengers of gamma-radiation such as carbonates or nitrates.

0 Bookmarks
 · 
109 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Application of radiation processing for drinking water, wastewater, and groundwater treatment is a cost effective process which may insure adequate availability of that resource worldwide. This paper summarizes the results of a Coordinated Research Project (organized by the IAEA) with participants from 10 countries with the purpose of describing the degradation mechanism of organic impurities, and establishing optimal treatment conditions. Decoloration, disinfection, microbiological and toxicological experiments are also mentioned. These experiments led to pilot plants and also to a large scale industrial realization of radiation technology. and Italy participated as an observer) intended to focus on those areas where there appeared to be highest probability for the successful application of the process.
    NUKLEONIKA. 01/2007; 52:137-144.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Persistent pesticide transformation products (TPs) are increasingly being detected among different environmental compartments, including groundwater and surface water. However, there is no sufficient experimental data on their toxicological potential to assess the risk associated with TPs, even if their occurrence is known. In this study, the interaction of chlorophenoxy herbicides (MCPA, mecoprop, 2,4-D and dichlorprop) and their main transformation products with calf thymus DNA by UV-visible absorption spectroscopy has been assessed. Additionally, the toxicity of the chlorophenoxy herbicides and TPs was also assessed evaluating the inhibition of acetylcholinesterase activity. On the basis of the results found, it seems that AChE is not the main target of chlorophenoxy herbicides and their TPs. However, the results found showed that the transformation products displayed a higher inhibitory activity when compared with the parent herbicides. The results obtained in the DNA interaction studies showed, in general, a slight effect on the stability of the double helix. However, the data found for 4-chloro-2-methyl-6-nitrophenol suggest that this transformation product can interact with DNA through a noncovalent mode.
    BioMed research international. 01/2014; 2014:709036.
  • [Show abstract] [Hide abstract]
    ABSTRACT: An electrochemical sensor for the determination of the chlorophenoxy herbicide MCPA has been developed, based on a combination of multi-walled carbon nanotubes with incorporated β-cyclodextrin and a polyaniline film modified glassy carbon electrode. The proposed molecular host-guest recognition based sensor has a high electrochemical sensitivity for the determination of MCPA. The electrochemical behaviour of MCPA at the chemically modified electrode was investigated in detail by cyclic voltammetry. The results indicate that the β-CD/MWCNT modified glassy carbon electrode exhibits efficient electrocatalytic oxidation of MCPA with high sensitivity, stability and lifetime. The analytical characteristics of this film were used for the quantitative determination of MCPA in natural waters. Cyclic voltammetry in phosphate buffer solution at pH 6.0, allowed the development of a method to determine MCPA, without any previous steps of extraction, clean-up, or derivatization, in the range of 10-100μmolL(-1), with a detection limit of 0.99μmolL(-1) in water. The results were statistically compared with those obtained through an established high-performance liquid chromatography technique, no significant differences having been found between the two methods.
    Talanta 09/2012; 99:288-93. · 3.50 Impact Factor

Full-text (3 Sources)

View
145 Downloads
Available from
May 22, 2014