Linked Life Data

1439732

Source:http://linkedlifedata.com/resource/pubmed/id/1439732

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1992-12-11
pubmed:abstractText
There is little doubt that organic matter plays a major role in the binding of pesticides in soil, and that this phenomenon is usually the most important cause for interaction of pesticides in the soil environment. Fulvic or humic acids are the chemicals most commonly involved in the binding interactions. Binding can occur with the original pesticide or a transformation product, the reaction being caused by abiotic agents or biotic agents (microbial or plant enzymes). The reactions or processes involved appear to be the same as those responsible for the formation of humic substances, i.e. for the humification process. Binding of pesticides to organic matter can occur by sorption (Van der Waal's forces, hydrogen bonding, hydrophobic bonding), electrostatic interactions (charge transfer, ion exchange or ligand exchange), covalent bonding or combinations of these reactions. Our investigation focused primarily on the binding of substituted phenols and aromatic amines to humus monomers and humic substances. In model reactions, we demonstrated the formation of covalent linkages between pesticides and humus constituents and fulvic or humic acids in the presence of phenol oxidases or clay minerals. With chlorinated phenols and carboxylic acids, it was possible to isolate and identify cross-coupling products and to elucidate the site and type of binding. The binding of chlorinated phenols to humic substances was determined by using 14C-labelled chemicals and by measuring the uptake of radioactivity by the humic material. These experiments provide a base for explaining the formation of bound residues in certain cases and for assuming the toxic potential of the immobilized pollutants.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0048-9697
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
123-124
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
205-17
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Biological and chemical interactions of pesticides with soil organic matter.
pubmed:affiliation
Laboratory of Soil Biochemistry, Pennsylvania State University, University Park 16802.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Review