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1.
Environ Sci Pollut Res Int ; 25(7): 6209-6217, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29243148

ABSTRACT

The effect of the pesticide etofenprox (0.76, 0.95, 1.18, 1.48, and 1.85 µg L-1) on survival, reproduction, and growth of Daphnia magna organisms was monitored using 21-day exposure tests. In order to test pesticide effects on D. magna, survival, length, mean total neonates per female, mean brood size, time to first reproduction, mean number broods per female, cumulative molting, and the population parameter intrinsic rate of natural increase (r) were used. Reproduction was seriously affected by etofenprox. Concentrations of etofenprox higher than 1.18 µg L-1affected all the reproductive parameters analyzed as well as individual length. However, daphnids' survival after 21 days of pesticide exposure did not exhibited differences among experimental and control groups. The no observed effect concentration (NOEC), the lowest observed effect concentration (LOEC), and the maximum acceptable toxicant concentration (MATC) were calculated for the different parameters. A MATC estimation of 1.32 µg L-1 was calculated for mean brood size, mean number of broods per female, mean number of neonates per female, and the intrinsic rate of growth population. Etofenprox effect on the algae Nannochloris oculata was also evaluated. The selected etofenprox concentrations did not affect algal growth rate (µ) after 24 h; however, N. oculata exposed during 48 and 72 h to the highest etofenprox concentration showed a decreased in its population rate.


Subject(s)
Daphnia/drug effects , Daphnia/growth & development , Insecticides/toxicity , Pyrethrins/toxicity , Water Pollutants, Chemical/toxicity , Animals , Dose-Response Relationship, Drug , Female , No-Observed-Adverse-Effect Level , Reproduction/drug effects , Survival Analysis
2.
J Pestic Sci ; 42(1): 7-15, 2017 Feb 20.
Article in English | MEDLINE | ID: mdl-30363130

ABSTRACT

Propanil stress response in the eel (Anguilla anguilla) was examined. Eels were exposed to 3.16 mg/L for 72 hr and allowed to recover for 96 hr. Plasma levels of cortisol, lactate dehydrogenase (LDH), alkaline phosphatase (AP), aspartate aminotransferase (AST), cholesterol, triglycerides, glucose, ammonium, lactate, albumin, and total proteins as well as electrolytes (chloride, sodium, potassium, calcium and phosphorus) were determined. As a consequence of exposure, cortisol, AP, AST, and LDH increased. A hyperglycemic condition, together with hyperlactemia, hypoalbuminemia, hypoproteinemia, hypercholesterolemia and hypertriglycemia was registered. Ammonium increased during exposure concomitantly to hyponatremia, hypochloremia, hypocalcemia, hypophosphatemia, and hypokatremia. During recovery, chloride, sodium, potassium, ammonium, albumin and LDH normalized. At the end of the experiment, fish still exhibited hyperglycemia and hyperlactemia. Hypercalcemia was observed. Cholesterol, triglycerides, AP, and AST did not recuperate. These findings are important for assessing potential risks for areas where fish are grown near intensive herbicide use (i.e., paddy fields).

3.
Article in English | MEDLINE | ID: mdl-27835067

ABSTRACT

In the present study, an ecotoxicological approach to the evaluation of Gemfibrozil (GEM) as an emerging organic pollutant was done. In order to assess its toxicity, tests were conducted using the cladocera Daphnia magna. Experiments were carried out at 22°C and 28°C. EC50, feeding behavior, and chronic toxicity tests (21 days) were evaluated in D. magna exposed to GEM as well as cholesterol levels at 21-day chronic exposure. D. magna GEM EC50 values (24 h) in our experimental conditions were 148.75 and 116.24 mg L-1 at 22°C and 28°C, respectively. Test concentrations of 0.1, 0.5, 1.0, 5.0 and 7.5 mg L-1 were selected for subacute and chronic experiments. Subacute short-term test (feeding study) was assessed after exposure to the toxicant. Filtration and ingestion rates of D. magna exposed animals did not show any significant difference (P > 0.05) with respect to control daphniids neither at 22°C nor at 28°C. Therefore, GEM test concentrations used in the present study did not reduce feeding behavior in D. magna. Temperature increased from 22°C to 28°C, which resulted in a decrease of the daphniids reproductive parameters such as brood size and number of young per female. Other parameters as longevity were not affected. The GEM concentrations used in the chronic test with D. magna did not affect daphniids longevity but some reproductive parameters as number of young per female or brood size were affected. Finally, a significant decreased in cholesterol levels was found in those animals exposed to the highest toxicant concentrations. More studies must be done to determine the possible implications of GEM in aquatic fauna and to derive its possible effects on the environment.


Subject(s)
Daphnia/drug effects , Gemfibrozil/toxicity , Hypolipidemic Agents/toxicity , Water Pollutants, Chemical/toxicity , Animals , Feeding Behavior/drug effects , Female , Lethal Dose 50 , Reproduction/drug effects , Temperature , Toxicity Tests, Chronic
4.
Environ Toxicol Pharmacol ; 35(3): 465-72, 2013 May.
Article in English | MEDLINE | ID: mdl-23501607

ABSTRACT

The present study investigates energy stores changes in the aquatic invertebrate Daphnia magna following a 5-d exposure to propanil. Juveniles of D. magna were exposed to sublethal propanil concentrations (0.07, 0.10, 0.21 and 0.55 mgl(-1)) which were used previously to test their effect on reproduction, growth and survival (21 days test) of D. magna. Glycogen, total lipids, proteins, and dry weight were determined in control and exposed daphnids at 24, 48, 72, 96 and 120 h. Data were used to calculate caloric content as biomarker of propanil exposure. Results showed a depletion of energy reserves in D. magna exposed to the herbicide. At 120 h of exposure to the highest propanil concentration (0.5 mgl(-1)), the reduction in daphnid reserves were glycogen (28%), proteins (28%) and lipids (31%), and caloric content was reduced in 27%. On the other hand, we found a positive correlation between caloric content and the chronic parameters intrinsic rate of natural increase and offspring per female when daphnids were exposed for 120 h to the herbicide.


Subject(s)
Daphnia/drug effects , Herbicides/toxicity , Propanil/toxicity , Water Pollutants, Chemical/toxicity , Animals , Arthropod Proteins/metabolism , Daphnia/metabolism , Glycogen/metabolism , Herbicides/administration & dosage , Lipid Metabolism , Propanil/administration & dosage , Toxicity Tests/methods
5.
Article in English | MEDLINE | ID: mdl-19217945

ABSTRACT

Short-term effects of tricyclazole on male zebrafish (Danio rerio) physiology were examined joint to the degree of recovery after exposure. Fish were exposed to 142 microg/L (1/100 LC(50)-96 h) of tricyclazole for 7 (Exp.1) and 14 days (Exp.2) and then allowed to recover for 7 or 14 more days, respectively. Whole-body triglycerides, cholesterol, glucose, lactate and total proteins were measured as well as the aspartate aminotransferase (AAT), alanine aminotransferase (AlAT), alkaline phosphatase (AP) and lactate dehydrogenase (LDH) activities as biomarkers of intermediary metabolism; gamma-glutamyl transpeptidase (gammaGT) as biomarker of oxidative detoxification processes and vitellogenin (Vtg) concentration as endpoint for endocrine disruptor effect were also determined. Corpulence factor (k) was calculated. Fungicide exposure in zebrafish resulted in an increased of triglycerides, cholesterol, glucose and lactate levels, however the total protein content did not change. LDH, AlAT and AAT enhanced while AP activity decreased. Corpulence factor (k) also decreased. At the end of the recovery periods cholesterol and glucose levels recovered whereas triglycerides and lactate continued to elevate. Induced disorders on the selected enzymes remained and did not recover at the end of experiments. Fish exhibited significant increases of Vtg during the overall experimental times as a consequence of the fungicide exposure. These findings are of importance in the assessment of the potential risk of new fungicides as tricyclazole on aquatic ecosystems.


Subject(s)
Environmental Exposure/adverse effects , Recovery of Function/drug effects , Recovery of Function/physiology , Thiazoles/toxicity , Zebrafish/physiology , Animals , Male , Thiazoles/administration & dosage , Zebrafish/metabolism
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