Artemia salina acute immobilization test: a possible tool for aquatic ecotoxicity assessment.

Despite the fact that the marine crustacean Artemia salina is extensively used in ecotoxicology, there is still a lack of information about its sensitivity to commonly used chemicals. In the presented study, acute toxicity of 18 commonly used chemicals - including organic solvents, industrial chemicals, metals and inorganic compounds - to A. salina was evaluated.

Comparison of Fenton's oxidation and ozonation for removal of estrogens.

This study compares efficiency of Fenton's oxidation and ozonation of 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) as two possible processes for removal of estrogens from aqueous solutions. The effectiveness of Fenton's oxidative removal was studied at different ratios of reagents Fe2+:H2O2 (1:0.5; 1:10; 1:20; 1:33), where with some molar ratios up to 100% removal of E2 and EE2 was achieved in the first few minutes of reaction.

Feasibility of Fenton's Oxidation for Removal of Estrogens from Aqueous Solutions.

Presented research has been focused on the effectiveness of degradation of natural (17-estradiol - E2) and synthetic (17α-ethinylestradiol - EE2) hormones with Fenton's oxidation. Numerous studies have demonstrated, that the impact of hormones on organisms was shown already at environmental concentrations close to 1 pg L-1, so their effective removal from wastewaters is important. Fenton's oxidation is very efficient in terms of oxidation of organics, while its main withdrawal is the formation of waste sludge, leading to adsorption of organics, which sometimes makes it impossible to reliably value the extent of actual degradation.

Toxicity potential of disinfection agent in tannery wastewater.

Wastewater from a tannery was investigated using chemical-specific analyses and assessment of the acute toxicity of the whole effluent over a 2-year period. The wastewater samples were overloaded with organic and inorganic compounds, and measured concentrations of the chemical parameters as well as dilution factors estimating acute toxicity, frequently exceeded the permissible limits for the discharge of wastewater from a tannery into the receiving stream. In the later part of the monitoring programme, the toxicity of the samples was significantly increased in comparison to the previous samples.

Aquatic toxicity of selected chemicals as a basic criterion for environmental classification.

In order to protect public health and the environment, the EU legislation has proposed a classification of dangerous substances. Chemicals are classified according to physico-chemical as well as toxicological and ecotoxicological properties. Environmental classification is based on inherent harmful potential of a substance to organisms and on its environmental fate, that is, degradation and bioaccumulation potential.

Comparison of diethylene glycol and phenol biodegradability by different test methods.

Biodegradation is generally recognised as an important removal mechanism for pollutants in natural ecosystems. It determines the concentration of substances in the environment. According to the legislation of the European Union, there are three levels for biodegradability testing protocols for chemicals which cover different test conditions.

Hazard identification for 3,5-dichlorophenol in the aquatic environment.

The risk assessment of substances in various environmental compartments is essential for their proper, safe and environmentally friendly production, handling, use and final deposition or destruction. Hazard identification is an important part of risk assessment. The aim of our research was to present a methodology for the hazard identification of substances dangerous to the aquatic environment according to the 93/21/EEC Directive relating to the classification, packaging and labelling of dangerous substances, from the adverse effect assessment of chemicals in European Union.