Abstract
The residual fate of 14C-ethion labeled at the ethyl group in chamomile flowers and oil was studied. 14C-ethion and some of its degradation products have been prepared for the present investigation. 14C-residues in its flowers and oil were determined at different time intervals. Chromatographic analysis of chamomile oil extracts revealed the presence of the parent compound together with four metabolites, which were identified as ethion monooxon, ethion dioxon, O,O-diethyl phosphorothioate, and O-ethyl phosphorothioate. Effect of drying on ethion residues in chamomile flowers was investigated. Ethion residues were decreased by sun drying of chamomile flowers. The percentage of removal was 18%–47%. Effect of using low cost adsorbents for removal of ethion residues from chamomile oil was investigated. The removal percentage due to adsorption was 100% for CaO and saw dust adsorbers and for watermelon peels, bagass, and rice bran adsorbers were 36%, 41%, and 90%, respectively. Our results proved that the addition of CaO saw dust and rice bran reduced the pesticide residues, so we recommend the addition of these adsorbents during the extraction process to reduce the risk of pesticide residues on chamomile oil.
[Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Figure S1: 1H NMR of Compound (IV)]
GRAPHICAL ABSTRACT