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Acute Toxicity and Biological Responses of Clarias gariepinus to Environmentally Realistic Chlorpyrifos Concentrations
2019
Kanu, K.C. | Ogbonna, O.A. | Mpamah, I.C.
In this study, the lethal toxicity, behavioral responses and hematotoxicity of formulated chlorpyrifos on Clarias gariepinus was evaluated. C. gariepinus fingerlings were exposed to 0.2 mg/L, 0.25 mg/L, 0.3 mg/L, 0.35 mg/L and 0.4 mg/L of the active ingredient chlorpyrifos to determine the lethal concentrations and behavioral effects. C. gariepinus juveniles (38.84±7.67g) were then exposed to 0.0256 mg/L and 0.0128 mg/L for 14 days to study somatic indices and haematological effects. The 24h, 48h, 72h and 96h LC50 were estimated as 0.292 (0.210 – 0.376) mg/L, 0.275 (0.252 – 0.297) mg/L, 0.263 (0.242 – 0.282) mg/L, and 0.256 (0.235 – 0.275) mg/L respectively. Hyper activity, loss of equilibrium, erratic swimming, trembling, respiratory distress and poor startle response were observed in fingerlings in response to acute toxic stress of chlorpyrifos. Liver somatic index (LSI) of exposed juveniles increased significantly (p<0.05) compared with control, while there was no statistically significant difference in all the haematological parameters of the exposed fishes compared with the control (p<0.05). The results indicate that the chlorpyrifos formulation was highly toxic and induced behavioral changes in C gariepinus fingerlings, while sub-lethal concentrations induced inflammation in the liver but had no effect on haematological parameters of Clarias gariepinus juveniles. LSI was sensitive to the sub-lethal concentrations and could serve as indicators or exposure to organophosphate insecticides.
Show more [+] Less [-]Organochlorine and heavy metal contamination in non-viable eggs and its relation to breeding success in a Spanish population of lesser kestrels (Falco naumanni).
1993
Negro J.J. | Donazar J.A. | Hiraldo F. | Hernandez L.M. | Fernandez M.A.
Pesticides in rainfall and air in Italy.
1993
Trevisan M. | Montepiani C. | Ragozza L. | Bartoletti C. | Ioannilli E. | Re A.A.M. del
Levels of polychlorinated biphenyls, organochlorine pesticides, mercury, cadmium, copper, selenium, arsenic, and zinc in the harbour seal, Phoca vitulina, in Norwegian waters.
1990
Skaare J.U. | Markussen N.H. | Norheim G. | Haugen S. | Holt G.
Organic contaminants in sediments from San Quintin Bay, Baja California, Mexico.
1996
Galindo E.A.G. | Celaya J.A.V. | Munoz G.F. | Sericano J.L.
Organochlorine pesticide residues in marine sediment and biota from the Northern Florida reef tract.
1995
Glynn P.W. | Rumbold D.G. | Snedaker S.C.
Persistent organochlorine residues in harbour porpoise (Phocoena phocoena) from the Black Sea.
1997
Tanabe S. | Madhusree B. | Ozturk A.A. | Tatsukawa R. | Miyazaki N. | Ozdamar E. | Aral O. | Samsun O. | Ozturk B.
Trace metals and organochlorines [DDT, DDE and HCH] in the coastal waters of Hong Kong.
1989
Phillips D.J.H.
Persistent organochlorines [DDT and HCH] in Japanese coastal waters: an introspective summary from a Far East developed nation.
1989
Tanabe S. | Kannan N. | Fukushima M. | Okamoto T. | Wakimoto T. | Tatsukawa R.
Spatio-temporal variability of water pollution by chlordecone at the watershed scale: what insights for the management of polluted territories?
2020
Mottes, Charles | Deffontaines, Landry | Charlier, Jean-Baptiste | Comte, Irina | Della Rossa, Pauline | Lesueur Jannoyer, Magalie | Woignier, Thierry | Adele, Georges | Tailame, Anne-Lise | Arnaud, Luc | Plet, Joanne | Rangon, Luc | Bricquet, Jean-Pierre | Cattan, Philippe
Chlordecone, applied on soils until 1993 to control banana weevil, has polluted water resources in the French West Indies for more than 40 years. At the watershed scale, chlordecone applications were not homogenous, generating a spatial heterogeneity of the pollution. The roles of climate, hydrology, soil, agronomy, and geology on watershed functioning generate a temporal heterogeneity of the pollution. This study questions the interactions between practices and the environment that induce such variability. We analyzed hydrological and water pollution datasets from a 2-year monitoring program on the Galion watershed in Martinique (French West Indies). We conjointly analyzed (i) weekly chlordecone (CLD) concentration monitored on 3 river sampling sites, (ii) aquifer piezometric dynamics and pollutions, and (iii) agricultural practices on polluted soils. Our results showed that chlordecone pollution in surface waters are characterized by annual trends and infra-annual variations. Aquifers showed CLD concentration 10 times higher than surface water, with CLD concentration peaks during recharge events. We showed strong interactions between rainfall events and practices on CLD pollution requiring a systemic management approach, in particular during post-cyclonic periods. Small sub-watershed with high CLD pollution appeared to be a substantial contributor to CLD mass transfers to the marine environment via rivers and should therefore receive priority management. We suggest increasing stable organic matter return to soil as well as external input of organic matter to reduce CLD transfers to water. We identified hydrological conditions—notably drying periods—and tillage as the most influential factors on CLD leaching. In particular, tillage acts on 3 processes that increases CLD leaching: organic matter degradation, modification of water paths in soil, and allophane clay degradation.
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