Toxicity of Selected Pharmaceuticals to the Anostracan Crustacean Thamnocephalus platyurus - Comparison of Sublethal and Lethal Effect Levels with the 1h Rapidtoxkit and the 24h Thamnotoxkit Microbiotests

- DOI: http://dx.doi.org/10.1065/espr2006.01.005 Background, Aims and Scope In view of the limited amount of information on the potential hazard of the ever increasing amounts of drugs in surface waters to aquatic biota, a study was undertaken to determine the effect levels of 28 selected pharmaceuticals to the crustacean test species Thamnocephalus platyurus. The drugs belong to 5 different groups: non steroidal anti-inflammatory agents, biocides, cardiovascular compounds, nervous system drugs and purine alkaloids. Methods Toxicity tests were carried out with the 1h Rapidtoxkit and the 24h Thamnotoxkit microbiotests in order to make a comparison of sublethal effects (visible as stress through absence of feeding) measured after a very short time of exposure (1h) and lethal effects after prolonged exposure (24h). Dilution series starting at 200 mg l–1 were prepared and applied, and median effects levels were calculated and transformed into Toxic Units (TU) for easy data comparison. Results and Discussion The toxic effects found have been ranked into 4 arbitrary toxicity classes: not toxic (TU<0.2), low toxicity (0.2<TU<1.0), toxic (1.0<TU<10) and very toxic (TU>10). The toxicity levels noted ranged from virtually no effects for a few of the pharmaceuticals, at the highest concentration tested out, to LC50's below 1 mg l–1 (>100 TU) for 3 nervous system drugs (Amitryptiline, Thioridazine and Chlorpromazine). According to the toxicity classification, 17 of the 28 compounds (i.e. 67%), belong to the same class for the lethal and the sublethal tests. More pronounced differences in effect levels between the two assays were observed mainly for the pharmaceuticals which were either not toxic or only slightly toxic at the 200 mg l–1 level. For 90% of the toxic drugs the ratio between the toxicity values for both tests is below 5. Conclusion An overall correlation coefficient of 0.96 was found between the 2 microbiotests, confirming the good predictive potential of the 1h stress-based Rapidtoxkit in revealing important biological effects (mortality) after more prolonged exposure of the crustacean test species to chemical compounds. Recommendation and Outlook The present study clearly shows that new microbiotests such as the 1h Rapidtoxkit and the 24h Thamnotoxkit are attractive tools for rapid cost-effective screening of 'new' pollutants such as drugs which may threaten the biological communities of the aquatic environment.     

Contamination levels and state assessment in the lakes of the Oliveri-Tindari Lagoon (North-Eastern Sicily,Italy)

The Oliveri-Tindari Lagoon, located in North-Eastern Sicily (Italy) and composed of six lakes, is subject to continuous environmental changes. An integrated study focusing on sediment features and levels of contamination was carried out for three of the six lakes, which are of ancient origin: Verde, Mergolo della Tonnara and Marinello. A high primary production (26.89 μg l^?1) was detected at Lake Verde; texture classification showed a typical grain size in the sediments of all lakes; the study of macronutrients highlighted 17.08 of total carbon in sediments from Lake Mergolo della Tonnara; toxic elements were detected at higher concentrations in the sediments of Lake Marinello in comparison to the others, while arsenic was found in high concentrations in all the samples tested, especially in Lake Verde, with a mean value of 17.25 mg kg^?1 dry weight (d.w.). All the organic contaminants, except 4, 4′-dichlorodiphenyldichloroethylene, were below the detection limits in the sediments. Minimal microbiological contamination was found in both water and sediment samples. In the latter, we isolated several bacterial strains thriving in the presence of arsenic, which play a role in the biogeochemical cycle of arsenic. These preliminary results, obtained for the first time using a multidisciplinary approach, provide general information about the Oliveri-Tindari Lagoon area.     

Framework for the uncertainty assessment in the impact pathway analysis with an application on a local scale in Spain

The estimation of damage estimates due to air emissions gives important basic knowledge for decision-making on the level of environmental politics and business strategies. Nowadays, a frequently applied method to estimate environmental damages is the Impact Pathway Analysis (IPA), which can be easily carried out using models such as EcoSense or PathWays. These models produce results in a relatively short term. However, there is a lack of reliability in the results. As in many other environmental software tools, the uncertainty is the key problem that makes it difficult to convince decision-makers by the outcomes of a study. Therefore, a framework that allows assessing the uncertainties within studies in which the IPA is applied on a local scale has been developed. In this assessment framework, the uncertainties of the used parameters, including their spatial and temporal variability, are taken into account. As the model is processing a huge quantity of data, one step of the assessment consists of a screening procedure to determine the parameters that are supposed to be fixed. For the other data, probability distributions have to be selected and classified into two groups: extensively available data for which average and standard deviation can be calculated and data based on little information. A quantification of the uncertainty can be completed by a stochastic model in the form of Monte Carlo (MC) simulation on the basis of the framework. As an illustration of the framework, we have applied it to a study on the installation of an advanced gas treatment in the municipal waste incinerator of Tarragona. It can be shown that the presented stochastic approach gives a lower geometric deviation than the analytical one and that the new gas treatment reduces the environmental damages without any doubt.     

Environmental impact assessment in flanders,belgium: An evaluation of the administrative procedure

Two years of experience with EIA in Flanders (northern Belgium) was evaluated in order to gain perspective on the effectiveness of the administrative procedure. The four essential characteristics of the EIA procedure that were evaluated are: completeness, open and public character, objectivity, and verifiability. Representatives of all parties involved in the EIA procedure were interviewed. The result of the evaluation is a list of major problems with EIA. Recommendations for a more efficient procedure are suggested at a time when a proposal for a new, comprehensive, and permanent EIA decree is being discussed. The evaluation of the administrative procedure for EIA in Flanders shows that several vital characteristics of the EIA procedure are lacking. This reduces the obligatory and open nature of the process, resulting in insufficient guarantees that the environment receives the altention it deserves during the decision-making process.     

Direct calorimetry of free-moving eels with manipulated thyroid status

In birds and mammals, the thyroid gland secretes the iodothyronine hormones of which tetraiodothyronine (T4) is less active than triiodothyronine (T3). The action of T3 and T4 is calorigenic and is involved in the control of metabolic rate. Across all vertebrates, thyroid hormones also play a major role in differentiation, development and growth. Although the fish thyroidal system has been researched extensively, its role in thermogenesis is unclear. In this study, we measured overall heat production to an accuracy of 0.1 mW by direct calorimetry in a free-moving European eel (Anguilla anguilla L.) with different thyroid status. Hyperthyroidism was induced by injection of T3 and T4, and hypothyroidism was induced with phenylthiourea. The results show for the first time at the organismal level, using direct calorimetry, that neither overall heat production nor overall oxygen consumption in eels is affected by hyperthyroidism. Therefore, we conclude that the thermogenic metabolism-stimulating effect of thyroid hormones (TH) is not present with a cold-blooded fish species like the European eel. This supports the concept that TH does not stimulate thermogenesis in poikilothermic species.     

Removal of chloride from ethylene glycol solution using alumina/zeolite membrane as a physical boundary between the organic and aqueous phases

The permeation of Cl^? ions from a NaCl/ethylene glycol (EG) solution during electrodialysis was investigated using alumina and alumina/zeolite membranes. Voltage changes had very little effect on Cl^? permeation through the alumina membrane, suggesting that the driving force for the permeation was concentration-gradient-induced diffusion, and not the electric field. Solvation of the Na⁺ ions by EG resulted in EG migration through the membrane. Replacement of the deionized water (electrolyte) in the anodic cell with NaOH resulted in increased Cl^? permeation, although a greater amount of EG migrated into the NaOH solution as well. No notable difference was observed in Cl^? permeation through the alumina and alumina/zeolite membranes, but EG migration decreased when using the latter membrane, suggesting that EG migration was prevented by the zeolite layer. The proposed alumina/zeolite membrane is, hence, useful for solvent recovery by electrodialysis, but its mechanical stability must be improved for industrial applications.     

Electrodialysis for NaCl/EG solution using ion-exchange membranes

A new concept for the recycling of poly(vinyl chloride) (PVC) has been introduced, including the dehydrochlorination of PVC in ethylene glycol (EG) with NaOH as a reactant, the subsequent separation of NaCl from EG by electrodialysis, and the recovery of chlorine for the synthesis of new PVC. In this work, the separation of NaCl by electrodialysis was investigated. About 98 % of the salt were recovered from EG, with less than 10 % of the EG permeating the membranes after 5 h.     

Über krystallisierte Acetylcellulose

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