Effects of long-term chlorpyrifos exposure on mortality and reproductive tissues of Banded Gourami (Trichogaster fasciata)

Abstract

This study assessed the long-term toxicity of chlorpyrifos on survival and reproduction of Banded Gourami by using mortality, gonado-somatic index (GSI) and histopathological observations as endpoints. Adult fish were exposed to five different concentrations of chlorpyrifos (0, 15, 50, 150, 500?µg/L) in 15 PVC tanks for 15, 30, 45, 60 and 75?days. Results showed that all male and female fish died after 15?days of 500?µg/L chlorpyrifos exposure. No consistent significant effect was observed for both male and female GSI. Furthermore, results showed dose- and time-dependent histopathological alterations for both ovary and testes. The 60-d No Observed Effect Concentration (NOEC) for most histopathological alterations of Banded Gourami ovary and testes was 50?μg/L, while 60-d NOEC for mortality of both male and female fish was < 15?μg/L. The results show that the long-term exposure to chlorpyrifos not only affect the reproductive tissues of Banded Gourami at exposure concentrations but also cause their mortality. Future studies should evaluate effects at lower concentrations.     

Comparative acute toxicity of two phytosanitary molecules,lambda-cyhalothrin and acetamiprid,on Nile Tilapia (Oreochromis Niloticus) juveniles

Abstract

This study aimed to compare the toxicity for fish of two active ingredients (lambda-cyhalothrin-20?g L^?1, a pyrethroid, and acetamiprid-15?g L^?1, a neonicotinoid) which are components of a commercial insecticide (Acer 35 EC) used in cotton crop in many West African countries. The juveniles of Oreochromis niloticus (4.01?±?0.34?g, mean body weight) were exposed for 96?h to increasing concentrations of active ingredients (lambda-cyhalothrin and acetamiprid) or a mixture similar to Acer 35 EC (composed by 20?g of chemical compound lambda-cyhalothrin and 15?g of acetamiprid dissolved in 1?L of acetone). The experiments were carried out under controlled conditions in aquaria according to OECD Guidelines. During the experiments, the behavioral responses (loss of balance, color change, hyperactivity, etc.) that usually precede death were observed in exposed fish. Mortalities were recorded in each aquarium and the LC₅₀-96h of each chemical was determined. The LC₅₀-96h obtained were respectively 0.1268, 0.0029, 182.9 and 0.5685?ppm for Acer 35 EC, lambda-cyhalothrin, acetamiprid and mixture. All insecticides used in this study had profound impact on Nile tilapia behavior which may confirm the neurotoxicity of each single active compound as well as of their mixture.     

发光细菌法在水质综合毒性在线检测中的应用

以海洋发光细菌费氏弧菌（Vibriofischeri）作为检测生物,采用冻干菌粉快速复苏技术,研究费氏弧菌在水质检测中的最佳测试温度和有效性测试条件,并对硫酸锌等多种毒物和几种实际水样进行发光抑制作用分析。研究表明,费氏弧菌冻干粉复苏菌液保存在2～5℃条件下能有效测试7d,最佳测试温度为15℃,最佳测试时间为15min。氯化汞、硫酸锌、硫酸镉等重金属和苯胺、多菌灵、甲醛等有机毒物对费氏弧菌均具有较强的光抑制作用,也即费氏弧菌对以上毒物较为敏感,并能够连续7d保持对同一浓度硫酸锌的敏感性较为一致。对几种实际水样的测试和分析表明,以费氏弧菌为指示生物的发光细菌法能够应用于水质环境安全的综合毒性在线监测预警中。     

Evaluation on the toxicity of ionic liquid mixture with antagonism and synergism to Vibrio qinghaiensis sp.-Q67

Ionic liquids (ILs) are a fascinating group of new chemicals with the potential to replace the classical volatile organic solvents, stimulating many applications in chemical industry. In case ILs are released to the environment, possible combined toxicity should be taken into account and it is, however, often neglected up to now. In this paper, therefore, the concentration-response curves (CRCs) of four groups of IL mixtures with various mixture ratios to Vibrio qinghaiensis sp.-Q67 were determined using the microplate toxicity analysis and were compared to the CRCs predicted by an additive reference model, the concentration addition (CA) or independent action (IA), to identify the toxicity interaction. It is showed that most of the IL mixture rays displayed the classical addition while the remaining rays exhibited antagonism or synergism. Moreover, it is found that the pEC₅₀ values of the mixture rays exhibiting antagonism or synergism are well correlated with the mixture ratio of a certain IL therein.     

Estrogen receptor mediated activity in bankside groundwater, with flood suspended particulate matter and floodplain soil - an approach combining tracer substance, bioassay and target analysis

Bankside groundwater is widely used as drinking water resource and, therefore, contamination has to be avoided. In the European Union groundwater protection is explicit subject to Water Framework Directive. While groundwater pollution may originate from different sources, this study investigated on impacts via flood events.Groundwater was sampled with increasing distance to the river Rhine near Karlsruhe, Germany. Samples were HPLC-MS-MS analyzed for the river contaminant carbamazepine to indicate river water infiltration, giving permanent presence in 250 m distance to the river (14-47 μg L⁻¹). Following a flood event, concentrations of about 16-20 μg L⁻¹ could also be detected in a distance of 750 m to the river. Furthermore, estrogenic activity as determined with the Yeast Estrogen Screen assay was determined to increase up to a 17β-ethinylestradiol equivalent concentration (E-EQ) = 2.9 ng L⁻¹ near the river, while activity was initially measured following the flood with up to E-EQ = 2.6 ng L⁻¹ in 750 m distance. Detections were delayed with increasing distance to the river indicating river water expansion into the aquifer.Flood suspended matter and floodplain soil were fractionated and analyzed for estrogenic activity in parallel giving up to 1.4 ng g⁻¹ and up to 0.7 ng g⁻¹, respectively. Target analysis focusing on known estrogenic active substances only explained <1% of measured activities.Nevertheless, river water infiltration was shown deep into bankside groundwater, thus, impacting groundwater quality. Therefore, flood events have to be in the focus when aiming for groundwater and drinking water protection as well as for implementation of Water Framework Directive.     

A biology-based dynamic approach for the reconciliation of acute and chronic toxicity tests: application to Daphnia magna

There is the need to integrate existing toxicity data in a coherent framework for extending their domain of applicability as well as their extrapolation potential. This integration would also reduce time and cost-consuming aspects of these tests and reduce animal usage. In this work, based on data extracted from literature, we have assessed the advantages that a dynamic biology-toxicant fate coupled model for Daphnia magna could provide when assessing toxicity data, in particular, the possibility to obtain from short-term (acute) toxicity test long-term (chronic) toxicity values taking into account the inherent variability of D. magna populations and the multiple sources of data. The results show that this approach overcomes some of the limitations of existing toxicity tests and that the prediction errors are considerably reduced when compared with the factor from 2 to 5 obtained using acute-to-chronic ratios.     

Determination of lipid peroxidation and cytotoxicity in calcium, magnesium, titanium and hectorite (SHCa-1) suspensions

This paper reports data on the relative ability of CaO, CaCl₂, MgO, MgCl₂, TiO₂, and hectorite (SHCa-1) to induce oxidative stress (as determined by lipid peroxidation, LP) in biological matrices. The effectiveness of structural (oxide form) versus soluble Ca and Mg to induce LP is compared. An assessment on cytotoxicity as affected by soluble and structural Ca, Mg, TiO₂ and SHCa-1 is also addressed. LP was screened and monitored using the Thiobarbituric Acid Reactive Substances (TBARS). The extent of TBARS production was found to vary with the type and initial concentration of the soluble or structural cation, Ca or Mg respectively. Obtained results showed higher magnitude values for the latter set of experiments. In the presence of TiO₂ no significant TBARS production was detected pointing out a negligible effect of TiO₂ on LP. At solid concentrations ca. 100 ppm, CaO appears to be more effective than SHCa-1 to induce LP. By contrast at ca. 25 ppm, MgO appears to be more effective than the clay mineral. The SHCa-1 LP-inducing activity has been proven to closely relate to structural Ca. The prevalence of mechanisms that may induce LP but not cytotoxicity (as determined by cell growth inhibition) was also addressed. Results on cell growth inhibition as affected by soluble and structural Ca, Mg, TiO₂ and hectorite provide evidence to support that structural Ca or Mg brings about significantly higher variations than soluble Ca.     

Histopathological effects of copper and lithium in the ramshorn snail, Marisa cornuarietis (Gastropoda, Prosobranchia)

The aim of this study was to determine and quantify effects of copper and lithium in tissues of early juveniles of the ramshorn snail, Marisa cornuarietis. For this purpose, hatchlings of M. cornuarietis were exposed for 7 days to a range of five different sublethal concentrations of copper (5, 10, 25, 50, and 75 μg Cu²⁺ L⁻¹) and lithium (50, 100, 200, 1000, and 5000 μg Li⁺ L⁻¹). Both metals changed the tissue structure of epidermis, hepatopancreas, and gills, varying between slight and strong reactions, depending on the copper and lithium concentration. The histopathological changes included alterations in epithelial and mucous cells of the epidermis, swelling of hepatopancreatic digestive cells, alterations in the number of basophilic cells, abnormal apices of digestive cells, irregularly shaped cilia and changes in the amount of mucus in the gills. The most sensible organ in M. cornuarietis indicating Cu or Li pollution is the hepatopancreas (LOECs were 10 μg Cu²⁺ L⁻¹, or 200 μg Li⁺ L⁻¹). In epidermis, mantle and gills relevant effects occurred with higher LOECs (50 μg Cu²⁺ L⁻¹, or 1000 μg Li⁺ L⁻¹). Base on LOECs, our results indicated that histopathological endpoints are high sensitivity to copper and lithium compared to endpoints for embryonic developmental toxicity.     

Quantification of nitrate leaching from German forest ecosystems by use of a process oriented biogeochemical model

Simulations with the process oriented Forest-DNDC model showed reasonable to good agreement with observations of soil water contents of different soil layers, annual amounts of seepage water and approximated rates of nitrate leaching at 79 sites across Germany. Following site evaluation, Forest-DNDC was coupled to a GIS to assess nitrate leaching from German forest ecosystems for the year 2000. At national scale leaching rates varied in a range of 0–>80 kg NO₃–N ha⁻¹ yr⁻¹ (mean 5.5 kg NO₃–N ha⁻¹ yr⁻¹). A comparison of regional simulations with the results of a nitrate inventory study for Bavaria showed that measured and simulated percentages for different nitrate leaching classes (0–5 kg N ha⁻¹ yr⁻¹:66% vs. 74%, 5–15 kg N ha⁻¹ yr⁻¹:20% vs. 20%, >15 kg N ha⁻¹ yr⁻¹:14% vs. 6%) were in good agreement. Mean nitrate concentrations in seepage water ranged between 0 and 23 mg NO₃–N l⁻¹.     

Integrated analysis of the effects of agricultural management on nitrogen fluxes at landscape scale

The integrated modelling system INITIATOR was applied to a landscape in the northern part of the Netherlands to assess current nitrogen fluxes to air and water and the impact of various agricultural measures on these fluxes, using spatially explicit input data on animal numbers, land use, agricultural management, meteorology and soil. Average model results on NH₃ deposition and N concentrations in surface water appear to be comparable to observations, but the deviation can be large at local scale, despite the use of high resolution data. Evaluated measures include: air scrubbers reducing NH₃ emissions from poultry and pig housing systems, low protein feeding, reduced fertilizer amounts and low-emission stables for cattle. Low protein feeding and restrictive fertilizer application had the largest effect on both N inputs and N losses, resulting in N deposition reductions on Natura 2000 sites of 10% and 12%, respectively.