Title of article :
Organochlorine and organophosphorus pesticide residues in the Atoya river Tbasin, Chinandega, Nicaragua
Author/Authors :
J.A.A، Castilho, نويسنده , , N.، Fenzl, نويسنده , , S.M.، Guillen, نويسنده , , F.S.، Nascimento, نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2000
Pages :
-522
From page :
523
To page :
0
Abstract :
The hydrographic basin of the Atoya river, located in the Department of Chinandega, one of the main cotton producing regions in Nicaragua, is intensively contaminated by pesticides. Samples of river waters and sediments, as well as strategically selected wells have been analyzed to study variations in the concentrations of organochlorine and organophosphorus pesticide residues between the dry season (November-April) and the rainy season (May-June). Generally, higher concentrations of pesticides have been detected in the river waters and sediments in the dry season. DDT, DDD, DDE compounds and toxaphene are the most frequent organochlorine residues found in the water and sediment samples, while endrin, aldrin, dieldrin and lindane are mainly found in the waters of rivers and wells. Organophosphorus compounds were rarely detected. However, residues of ethion, methyl-parathion and ethyl-parathion were found in high concentrations in some river and well water samples. Generally, organochlorine compounds tend to accumulate in the fine grain-size fractions, rich in organic matter, A except DDE, which concentrates basically in the coarse grain-size fractions.
Keywords :
Organochlorine and organophosphorus pesticides , seasonal variation , Nicaragua , Basin of the Atoya river
Journal title :
ENVIRONMENTAL POLLUTION
Serial Year :
2000
Journal title :
ENVIRONMENTAL POLLUTION
Record number :
38852
Link To Document :
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