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Chlorpyrifos pesticide toxicity on erythrocyte sedimentation rate in fish, Channa punctatus (Bloch)  [PDF]
FA Malla,G Sharma,S Singh
Biology and Medicine , 2009,
Abstract: Almost all the pesticides and more particularly the synthetic pesticides used, find there way into water bodies alter themetabolism of aquatic organisms is known long back. In the present investigation, the effect of sub lethalconcentration of chlorpyrifos toxicity on fish Channa punctatus were studied after 24hrs, 48hrs, 72hrs and 96hrsexposure respectively. Chlorpyrifos is an organophosphate insecticide that kills insects by disrupting there nervoussystem and is effective against a wide range of plant eating insects. Suspected effects of chlorpyrifos exposureinclude birth defects, increased rate of leukemia and immune system abnormalities. The results indicated a significantincrease in ESR (mm/hr) 2.57mm/hr, 2.60mm/hr, 2.71mm/hr and 2.83mm/hr when compared to control group2.56mm/hr fallowing both acute and sub acute exposure of chlorpyrifos.
A review of Dichlorvos toxicity in fish  [cached]
Current World Environment , 2013, DOI: 10.12944/cwe.8.1.08
Abstract: Among the wide majority of pesticides, dichlorvos (2, 2-dichlorovinyl dimethyl phosphate), a organophosphate compound, is commonly used as agricultural insecticide. It is extremely toxic to non target organisms like fish and hampers fish health through impairment of metabolism, sometimes leading to death. As one of the few organophosphates still registered for use, dichlorvos has elicited worldwide concern for many reasons. This study is a review of potential adverse effects of dichlorvos in fish
Ammonia Production, Excretion, Toxicity, and Defense in Fish: A Review  [PDF]
Yuen K. Ip,Shit F. Chew
Frontiers in Physiology , 2010, DOI: 10.3389/fphys.2010.00134
Abstract: Many fishes are ammonotelic but some species can detoxify ammonia to glutamine or urea. Certain fish species can accumulate high levels of ammonia in the brain or defense against ammonia toxicity by enhancing the effectiveness of ammonia excretion through active transport, manipulation of ambient pH, or reduction in ammonia permeability through the branchial and cutaneous epithelia. Recent reports on ammonia toxicity in mammalian brain reveal the importance of permeation of ammonia through the blood–brain barrier and passages of ammonia and water through transporters in the plasmalemma of brain cells. Additionally, brain ammonia toxicity could be related to the passage of glutamine through the mitochondrial membranes into the mitochondrial matrix. On the other hand, recent reports on ammonia excretion in fish confirm the involvement of Rhesus glycoproteins in the branchial and cutaneous epithelia. Therefore, this review focuses on both the earlier literature and the up-to-date information on the problems and mechanisms concerning the permeation of ammonia, as NH3, or proton-neutral nitrogenous compounds, across mitochondrial membranes, the blood–brain barrier, the plasmalemma of neurons, and the branchial and cutaneous epithelia of fish. It also addresses how certain fishes with high ammonia tolerance defend against ammonia toxicity through the regulation of the permeation of ammonia and related nitrogenous compounds through various types of membranes. It is hoped that this review would revive the interests in investigations on the passage of ammonia through the mitochondrial membranes and the blood–brain barrier of ammonotelic fishes and fishes with high brain ammonia tolerance, respectively.
Chlorpyrifos chronic toxicity in broilers and effect of vitamin C  [PDF]
A.M. Kammon,R.S. Brar,S. Sodhi,H.S. Banga
Open Veterinary Journal , 2011,
Abstract: An experiment was conducted to study chlorpyrifos chronic toxicity in broilers and the protective effect of vitamin C. Oral administration of 0.8 mg/kg body weight (bw) (1/50 LD50) chlorpyrifos (Radar ), produced mild diarrhea and gross lesions comprised of paleness, flaccid consistency and slightly enlargement of liver. Histopathologically, chlorpyrifos produced degenerative changes in various organs. Oral administration of 100 mg/kg bw vitamin C partially ameliorated the degenerative changes in kidney and heart. There was insignificant alteration in biochemical and haematological profiles. It is concluded that supplementation of vitamin C reduced the severity of lesions induced by chronic chlorpyrifos toxicity in broilers.
Acute Toxicity and Neurotoxicity of Chlorpyrifos in Black Tiger Shrimp, Penaeus monodon  [PDF]
Tassanee Eamkamon,Sirawut Klinbunga,Kumthorn Thirakhupt,Piamsak Menasveta
EnvironmentAsia , 2012,
Abstract: Acute toxicity and neurotoxicity of chlorpyrifos were determined in black tiger shrimp, P. monodon. LC50 values after 24 to 96 h of exposure were between 149.55 and 59.16 nmol/L. To determine the neurotoxicity of chlorpyrifos, the inhibition of acetylcholinesterase was monitored in the gill of the shrimps exposed to lethal (0.019, 0.194, and 1.942 μmol/L) and sub-lethal (0.019, 0.194, and 1.942 nmol/L) concentrations of chlorpyrifos. In lethal dose exposure, the AChE activities observed in shrimp exposed to 0.194, and 1.942 μmol/L of chlorpyrifos were significantly lower (1.7 and 3.3 times) than that of control shrimp after 30 min of exposure (p<0.05). In sub-lethal exposure tests, the AChE activity of shrimp was significantly lower (1.9 times) than that of control shrimp after exposure to 1.942 nmol/L of chlorpyrifos for 72 h (p<0.05). The sensitive reduction of AChE activity at the sub-lethal concentration, which was 30 times lower than 96 h LC50 value found in this study, indicates the potential use as a biomarker of chlorpyrifos exposure.
Toxicity assessment for chlorpyrifos-contaminated soil with three di erent earthworm test methods
Toxicity assessment for chlorpyrifos-contaminated soil with three different earthworm test methods

ZHOU Shi-ping,DUAN Chang-qun,FU Hui,CHEN Yu-hui,WANG Xue-hua,YU Ze-fen,
ZHOU Shi-ping
,DUAN Chang-qun,FU Hui,CHEN Yu-hui,WANG Xue-hu,YU Ze-fen

环境科学学报(英文版) , 2007,
Abstract: Earthworm toxicity tests are useful tools for terrestrial risk assessment but require a hierarchy of test designs that differ in effect levels (behavior, sublethal, lethal). In this study, the toxicity of chlorpyrifos contaminated soil on earthworms was assessed. In addition to the acute and chronic tests, an avoidance response test was applied. Earthworms were exposed to sublethal and lethal concentration of chlorpyrifos, and evaluated for acute toxicity, growth, fecundity and avoidance response after a certain exposure period. The test methods covered all important ecological relevant endpoints (acute, chronic, behavioral). Concentration of 78.91 mgkg, chlorpyrifos caused significant toxic effects in all test methods, but at lower test concentrations, only significant chronic toxic effects could be observed. In present study, chlorpyrifos had adverse effect on growth and fecundity in earthworm exposed to 5 mgkg chlorpyrifos after eight weeks. The avoidance response test, however, showed significant repellent effects at concentration of 40 mgkg chlorpyrifos. For chlorpyrifos, concentration affecting avoidance response was far greater than growth and fecundity, it seemed likely that earthworms were not able to escape from pesticide-contaminated soil into the clean soil in field and hence were exposed continuously to elevated concentrations of pesticides.
Toxicity of Chlorpyrifos and Dimethoate to the Ciliate Urostyla grandis, with Notes on Their Effects on Cell Ultrastructure Toxicity of Chlorpyrifos and Dimethoate to the Ciliate Urostyla grandis, with Notes on Their Effects on Cell Ultrastructure  [PDF]
MU Weijie,WARREN Alan,PAN Xuming,YING Chen
- , 2018,
Abstract: Chlorpyrifos and dimethoate are overused agricultural pesticides that can trigger trophic cascades, resulting in toxicity to both terrestrial and aquatic organisms as well as altered ecosystems. In previous studies, substantial attention has been given to the effects of pesticides on vertebrate species and, to a lesser extent, species of zooplankton. The present study was designed to show that the fission time effective concentration in ciliates is a potential aquatic detection index for environmental monitoring. The ciliate Urostyla grandis was treated with doses of chlorpyrifos and dimethoate. After exposed to the pesticides, the LC_(50)(i.e., concentration that killed 50% of the ciliate cells within 24 h) values were 0.029 mg L~(-1) for chlorpyrifos and 0.0685 mg L~(-1) for dimethoate. The fission time effective concentrations after 168 h of exposure were 0.0075–0.0093 mg L~(-1) for chlorpyrifos and 0.2640–0.2750 mg L~(-1) for dimethoate. These results show that the fission time effective concentration is lower than the LC_(50) value in ciliates, indicating that fission time effective concentration is more suitable than the LC_(50) value for environmental monitoring using ciliates. The effects of chlorpyrifos and dimethoate on ciliate cell ultrastructures included agglutination of chromatin in the macronucleus, protruded and discontinuous macronuclear and micronuclear membranes, loss of integrity of mitochondrial membranes and contents, and abscission and deformation of the adoral zone of membranelles
Evaluation of the Reproductive Toxicity of Chlorpyrifos Methyl, Diazinon and Profenofos Pesticides in Male Rats  [PDF]
Nour El-Hoda A. Zidan
International Journal of Pharmacology , 2009,
Abstract: The toxic effects of organophosphorus pesticides (i.e., chlorpyrifos methyl, diazinon and profenofos) on male reproductive system of rats were evaluated. Rats received pesticides mixed with powdered feed at concentrations of 5 and 50 ppm of each pesticide for 65 successive days. Sex organs weight, semen picture, concentrations of the hormones [i.e., testosterone, Luteinizing Hormone (LH) and Follicle Stimulating Hormone (FSH)], activities of acetylcholinesterase (AChE) and histopathological changes in testes were the criteria used to evaluate the reproductive toxicity of the treated rats. Results showed that the effect of all tested pesticides on testes and seminal vesicles weights was dose-dependent since all tested pesticides at 50 ppm significantly decreased their weights. Serum AChE activity was inhibited with all tested pesticides. Both the concentrations of the tested pesticides decreased sperm count associated with increase in the number of morphologically abnormal spermatozoa of treated rats; however sperm motility was significantly decreased with the highest concentration of the tested pesticides. A decrease in the serum testosterone was observed in all treated groups; however LH and FSH levels were decreased with the highest concentration of the tested pesticides. Tissues of treated rat’s testes showed slight alterations when histopathologically examined especially with the higher concentrations.
Studies on Acute Toxicity of Metals to the Fish, Catla catla  [PDF]
Sajid Abdullah,Muhammad Javed
Pakistan Journal of Biological Sciences , 2006,
Abstract: Acute toxicity of metals viz., iron, zinc, lead, nickel and manganese to the fish, Catla catla has been studied. These tests included the determination of 96 h LC50 and lethal toxicity of heavy metals to the fish. These tests were performed, separately, at constant temperature, pH and hardness of 30°C, and 100 mg L-1 respectively. Three fish age groups viz. 30, 0 and 90 day were tested for their sensitivity to metals toxicity. The impacts of physico-chemical variables were also studied towards sensitivity of fish to metals toxicity. The 96 h LC50 and lethal concentrations of all metals varied significantly in fish. This fish showed significantly highest tolerance (determined as LC50) against iron, followed by that of manganese, lead, zinc and nickel. However, non-significant differences for 96 h LC50 tolerance limits towards zinc and lead were found. Among the three fish age groups, 0 day fish were more sensitive to metals toxicity, followed by that of 60 and 90 day respectively. The responses of three fish age groups and five metals were statistically significant. Among the three age groups, 0 day fish showed significantly higher tolerance against all metals than that of 60 and 30 day fish. The ammonia excretion by the fish increased, significantly, with concomitant increase in metal concentrations of the mediums while dissolved oxygen content of the test medium decreased at higher metal concentrations. Sodium had slight protective effect against metals toxicity.
Changes in Behavior and Brain Acetylcholinesterase Activity in Mosquito Fish, Gambusia affinis in Response to the Sub-Lethal Exposure to Chlorpyrifos  [PDF]
J. Venkateswara Rao,Ghousia Begum,R. Pallela,P. K. Usman,R. Nageswara Rao
International Journal of Environmental Research and Public Health , 2005, DOI: 10.3390/ijerph2005030013
Abstract: Sub-lethal studies of chlorpyrifos, O,O-diethyl-O-(3,5,6-trichloro-2-pyridyl) phosphorothioate on mosquito fish, Gambusia affinis were carried out in vivo, for 20 days to assess the locomotor behavior in relation to bioaccumulation and interaction with a targeted enzyme, acetylcholinesterase (AChE, EC: Fish exposed to sub-lethal concentration of 60 Ag/L (1/5 of LC50) were under stress, and reduced their locomotor behavior like distance travelled per unit time (m/min) and swimming speed (cm/sec) with respect to the length of exposure. The alteration in locomotor behavior of fish may be due to an accumulation of acetylcholine (ACh), a neurotransmitter at synaptic junctions, due to the inhibition of AChE enzyme activity (40 to 55%) in brain and also bioaccumulation of the toxicant in different parts of fish. The bioaccumulation values indicated that the accumulation of chlorpyrifos was maximum in viscera followed by head and body. The average bioconcentration values are 0.109, 0.009 and 0.004 Ag/g for viscera, head and body with depuration rates of 2.24, 1.69 and 0.39 ng/h respectively. It is evident from the results that the sub-lethal concentration [1/5 of LC50; equivalent to Lowest Observed Effect Concentration (LOEC)] of chlorpyrifos can able to alter the locomotor behavior of G. affinis in relation to the length of exposure. The findings revealed that the locomotor activity of test organism could be considered as a suitable marker to evaluate the affect of toxicant even at LOEC levels.
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