Cargando…

Screening of pesticide residues in soil and water samples from agricultural settings

BACKGROUND: The role of agricultural practices in the selection of insecticide resistance in malaria vectors has so far been hypothesized without clear evidence. Many mosquito species, Anopheles gambiae in particular, lay their eggs in breeding sites located around agricultural settings. There is a...

Descripción completa

Detalles Bibliográficos
Autores principales: Akogbéto, Martin C, Djouaka, Rousseau F, Kindé-Gazard, Dorothée A
Formato: Texto
Lenguaje:English
Publicado: BioMed Central 2006
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1513586/
https://www.ncbi.nlm.nih.gov/pubmed/16563153
http://dx.doi.org/10.1186/1475-2875-5-22
_version_ 1782128509237329920
author Akogbéto, Martin C
Djouaka, Rousseau F
Kindé-Gazard, Dorothée A
author_facet Akogbéto, Martin C
Djouaka, Rousseau F
Kindé-Gazard, Dorothée A
author_sort Akogbéto, Martin C
collection PubMed
description BACKGROUND: The role of agricultural practices in the selection of insecticide resistance in malaria vectors has so far been hypothesized without clear evidence. Many mosquito species, Anopheles gambiae in particular, lay their eggs in breeding sites located around agricultural settings. There is a probability that, as a result of farming activities, insecticide residues may be found in soil and water, where they exercise a selection pressure on the larval stage of various populations of mosquitoes. To confirm this hypothesis, a study was conducted in the Republic of Benin to assess the environmental hazards which can be generated from massive use of pesticides in agricultural settings. METHODS: Lacking an HPLC machine for direct quantification of insecticide residues in samples, this investigation was performed using indirect bioassays focussed on the study of factors inhibiting the normal growth of mosquito larvae in breeding sites. The speed of development was monitored as well as the yield of rearing An. gambiae larvae in breeding sites reconstituted with water and soil samples collected in agricultural areas known to be under pesticide pressure. Two strains of An. gambiae were used in this indirect bioassay: the pyrethroid-susceptible Kisumu strain and the resistant Ladji strain. The key approach in this methodology is based on comparison of the growth of larvae in test and in control breeding sites, the test samples having been collected from two vegetable farms. RESULTS: Results obtained clearly show the presence of inhibiting factors on test samples. A normal growth of larvae was observed in control samples. In breeding sites simulated by using a few grams of soil samples from the two vegetable farms under constant insecticide treatments (test samples), a poor hatching rate of Anopheles eggs coupled with a retarded growth of larvae and a low yield of adult mosquitoes from hatched eggs, was noticed. CONCLUSION: Toxic factors inhibiting the hatching of anopheles eggs and the growth of larvae are probably pesticide residues from agricultural practices. Samples used during this indirect assay have been stored in the laboratory and will be analysed with HPLC techniques to confirm hypothesis of this study and to identify the various end products found in soil and water samples from agricultural settings under pesticide pressure.
format Text
id pubmed-1513586
institution National Center for Biotechnology Information
language English
publishDate 2006
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-15135862006-07-22 Screening of pesticide residues in soil and water samples from agricultural settings Akogbéto, Martin C Djouaka, Rousseau F Kindé-Gazard, Dorothée A Malar J Research BACKGROUND: The role of agricultural practices in the selection of insecticide resistance in malaria vectors has so far been hypothesized without clear evidence. Many mosquito species, Anopheles gambiae in particular, lay their eggs in breeding sites located around agricultural settings. There is a probability that, as a result of farming activities, insecticide residues may be found in soil and water, where they exercise a selection pressure on the larval stage of various populations of mosquitoes. To confirm this hypothesis, a study was conducted in the Republic of Benin to assess the environmental hazards which can be generated from massive use of pesticides in agricultural settings. METHODS: Lacking an HPLC machine for direct quantification of insecticide residues in samples, this investigation was performed using indirect bioassays focussed on the study of factors inhibiting the normal growth of mosquito larvae in breeding sites. The speed of development was monitored as well as the yield of rearing An. gambiae larvae in breeding sites reconstituted with water and soil samples collected in agricultural areas known to be under pesticide pressure. Two strains of An. gambiae were used in this indirect bioassay: the pyrethroid-susceptible Kisumu strain and the resistant Ladji strain. The key approach in this methodology is based on comparison of the growth of larvae in test and in control breeding sites, the test samples having been collected from two vegetable farms. RESULTS: Results obtained clearly show the presence of inhibiting factors on test samples. A normal growth of larvae was observed in control samples. In breeding sites simulated by using a few grams of soil samples from the two vegetable farms under constant insecticide treatments (test samples), a poor hatching rate of Anopheles eggs coupled with a retarded growth of larvae and a low yield of adult mosquitoes from hatched eggs, was noticed. CONCLUSION: Toxic factors inhibiting the hatching of anopheles eggs and the growth of larvae are probably pesticide residues from agricultural practices. Samples used during this indirect assay have been stored in the laboratory and will be analysed with HPLC techniques to confirm hypothesis of this study and to identify the various end products found in soil and water samples from agricultural settings under pesticide pressure. BioMed Central 2006-03-24 /pmc/articles/PMC1513586/ /pubmed/16563153 http://dx.doi.org/10.1186/1475-2875-5-22 Text en Copyright © 2006 Akogbéto et al; licensee BioMed Central Ltd. http://creativecommons.org/licenses/by/2.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( (http://creativecommons.org/licenses/by/2.0) ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research
Akogbéto, Martin C
Djouaka, Rousseau F
Kindé-Gazard, Dorothée A
Screening of pesticide residues in soil and water samples from agricultural settings
title Screening of pesticide residues in soil and water samples from agricultural settings
title_full Screening of pesticide residues in soil and water samples from agricultural settings
title_fullStr Screening of pesticide residues in soil and water samples from agricultural settings
title_full_unstemmed Screening of pesticide residues in soil and water samples from agricultural settings
title_short Screening of pesticide residues in soil and water samples from agricultural settings
title_sort screening of pesticide residues in soil and water samples from agricultural settings
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1513586/
https://www.ncbi.nlm.nih.gov/pubmed/16563153
http://dx.doi.org/10.1186/1475-2875-5-22
work_keys_str_mv AT akogbetomartinc screeningofpesticideresiduesinsoilandwatersamplesfromagriculturalsettings
AT djouakarousseauf screeningofpesticideresiduesinsoilandwatersamplesfromagriculturalsettings
AT kindegazarddorotheea screeningofpesticideresiduesinsoilandwatersamplesfromagriculturalsettings