Document Detail


Using a freshwater amphipod in situ bioassay as a sensitive tool to detect pesticide effects in the field.
MedLine Citation:
PMID:  12729231     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
In situ testing represents an alternative to conventional laboratory toxicity testing of field samples. Juvenile Paramelita nigroculus (Crustacea: Amphipoda) were exposed in situ in two rivers downstream of fruit orchard areas in the Western Cape, South Africa. Exposure took place during six time intervals (3-7 d), of which three represented the first rainfall-induced edge-of-field runoff events of the wet season, which was about two months after the last pesticide application. Survival rates were significantly reduced (35-70%) during runoff events 1 and 2 at both sites. No difference was observed from the respective no-runoff survival rate (>90%) during event 3. Peak levels of total insecticides (azinphosmethyl, chlorpyrifos, endosulfan, and prothiofos) in samples taken with water level-triggered samplers during the runoff events were between 0.03 and 0.26 microg/L in filtered water and between 305 and 870 microg/kg in suspended particles during runoff events 1 and 2 and only up to 0.01 microg/L and 101 microg/kg during event 3. Total suspended solids (TSS) varied between 400 and 700 mg/L during all three runoff events but never exceeded 65 mg/L during no-runoff time intervals. A laboratory experiment revealed that uncontaminated TSS levels of 1,500 mg/L during a 7-d exposure caused insignificant mortality (<2.5%) in P. nigroculus. No acute toxicity was observed in standard 48-h toxicity tests with juvenile Daphnia pulex using the filtered water samples taken during runoff and no-runoff conditions. It is concluded that the observed mortalities were caused by particle-associated pesticides and that the present amphipod in situ bioassay represents a sound and sensitive tool to detect runoff-related insecticide effects under field conditions.
Authors:
Ralf Schulz
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Environmental toxicology and chemistry / SETAC     Volume:  22     ISSN:  0730-7268     ISO Abbreviation:  Environ. Toxicol. Chem.     Publication Date:  2003 May 
Date Detail:
Created Date:  2003-05-05     Completed Date:  2003-07-08     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8308958     Medline TA:  Environ Toxicol Chem     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1172-6     Citation Subset:  IM    
Affiliation:
Department of Zoology, University of Stellenbosch, Private Bag XI, Matieland 7602, South Africa. Ralf.Schulz@syngenta.com
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MeSH Terms
Descriptor/Qualifier:
Agriculture
Amphipoda / drug effects*
Animals
Azinphosmethyl / analysis
Biological Assay / methods*
Biological Markers
Chlorpyrifos / analysis
Endosulfan / analysis
Fresh Water / analysis*
Fruit
Geologic Sediments / analysis
Pesticides / analysis*,  toxicity
Rain
Time Factors
Water Pollutants, Chemical / analysis*,  toxicity
Chemical
Reg. No./Substance:
0/Biological Markers; 0/Pesticides; 0/Water Pollutants, Chemical; 115-29-7/Endosulfan; 2921-88-2/Chlorpyrifos; 86-50-0/Azinphosmethyl

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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