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Owing to its proven toxicity and mutagenicity, arsenic is regarded a principal pollutant in water used for drinking. The objective of this study was the toxicological and chemical evaluation of groundwater samples obtained from arsenic enriched drinking water wells before and after electrochemical and ozone-UV-H2O2- based advanced oxidation processes (EAOP). For this purpose, acute toxicity test with Daphnia magna and chronic toxicity test with Lemna minor L. were employed as well as in vitro bioassays using human peripheral blood lymphocytes (HPBLs). Several oxidative stress parameters were estimated in L.minor. Physicochemical analysis showed that EAOP treatment was highly efficient in arsenic but also in ammonia and organic compound removal from contaminated groundwater. Untreated groundwater caused only slight toxicity to HPBLs and D. magna in acute experiments. However, 7-day exposure of L. minor to raw groundwater elicited genotoxicity, a significant growth inhibition and oxidative stress injury. The observed genotoxicity and toxicity of raw groundwater samples was almost completely eliminated by EAOP treatment. Generally, the results obtained with L. minor were in agreement with those obtained in the chemical analysis suggesting the sensitivity of the model organism in monitoring of arsenic- contaminated groundwater. In parallel to chemical analysis, the implementation of chronic toxicity bioassays in a battery is recommended in the assessment of the toxic and genotoxic potential of such complex mixtures.

Acrylamide is a monomer widely used as an intermediate in the production of organic chemicals, e.g. polyacrylamides (PAMs). Since PAMs are low cost chemicals with applications in various industries and waste- and drinking water treatment, a certain amount of non-polymerised acrylamide is expected to end up in waterways. PAMs are non-toxic but acrylamide induces neurotoxic effects in humans and genotoxic, reproductive, and carcinogenic effects in laboratory animals. In order to evaluate the effect of acrylamide on freshwater organisms, bioassays were conducted on four species: algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata, duckweed Lemna minor and water flea Daphnia magna according to ISO (International Organization for Standardisation) standardised methods. This approach ensures the evaluation of acrylamide toxicity on organisms with different levels of organisation and the comparability of results, and it examines the value of using a battery of low-cost standardised bioassays in the monitoring of pollution and contamination of aquatic ecosystems. These results showed that EC50 values were lower for Desmodesmus subspicatus and Pseudokirchneriella subcapitata than for Daphnia magna and Lemna minor, which suggests an increased sensitivity of algae to acrylamide. According to the toxic unit approach, the values estimated by the Lemna minor and Daphnia magna bioassays, classify acrylamide as slightly toxic (TU=0-1; Class 1). The results obtained from algal bioassays (Desmodesmus subspicatus and Pseudokirchneriella subcapitata) revealed the toxic effect of acrylamide (TU=1-10; Class 2) on these organisms.

Environmental context Various UV-filtering chemicals are added to sunscreens in order to protect humans from the harmful effects of the sun. As a consequence of disinfection processes in swimming pools, sunscreen components may be chlorinated and change their structure and properties, leading to derivatives with higher toxicity. The safety of sunscreen components as well as that of their transformation products during their use requires further study. Abstract In this work is presented a synthesis pathway for the UV filter hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate (DHHB) and its chlorinated by-products in order to investigate the transformation behaviour and toxicity changes of DHHB during chlorination disinfection treatment. Acute toxicity was measured using standardised tests with aquatic model organisms. The potency of DHHB was compared with other benzophenone-like UV filters tested in the same experimental set-up. The toxicity of chlorinated compounds tested with photobacteria was found to be in a similar range to that of the starting compound. Microalgae were more sensitive to DHHB than to its chlorinated by-products, whereas daphnids were affected more by DHHB's chlorinated products. The comparative toxicity data showed DHHB and even more its chlorinated by-products as more highly biologically potent to daphnids than other tested UV filters. The toxic potential of benzophenone-like UV filters should be interpreted together with data on their chemical properties, chlorination effects and affected organisms. Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3632]

There is a growing interest for the application of biomakers to field-collected earthworms. Therefore we have evaluated the usability of native populations of endogeic, widely distributed earthworm Aporrectodea caliginosa in the assessment of soil genotoxicity using the Comet assay. Validation of the Comet assay on earthworm coelomocytes has been established using commercially available Eisenia fetida exposed to copper, cadmium, and pentachlorophenol, along with A. caliginosa exposed to copper in a filter paper contact test. Neutral red retention time (NRRT) assay was conducted on copper exposed and field-collected earthworms. Significant DNA and lysosomal damage was measured using Comet and NRRT assays in native populations of A. caliginosa sampled from the polluted soils in the urban area in comparison to the earthworms from the reference site. The results of this study confirm the employment of A. caliginosa as a suitable species for the in situ soil toxicity and genotoxicity field surveys.

Acrylamide is a monomer widely used as an intermediate in the production of organic chemicals, e.g. polyacrylamides (PAMs). Since PAMs are low cost chemicals with applications in various industries and waste- and drinking water treatment, a certain amount of non-polymerised acrylamide is expected to end up in waterways. PAMs are non-toxic but acrylamide induces neurotoxic effects in humans and genotoxic, reproductive, and carcinogenic effects in laboratory animals. In order to evaluate the effect of acrylamide on freshwater organisms, bioassays were conducted on four species: algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata, duckweed Lemna minor and water flea Daphnia magna according to ISO (International Organization for Standardisation) standardised methods. This approach ensures the evaluation of acrylamide toxicity on organisms with different levels of organisation and the comparability of results, and it examines the value of using a battery of low-cost standardised bioassays in the monitoring of pollution and contamination of aquatic ecosystems. These results showed that EC50 values were lower for Desmodesmus subspicatus and Pseudokirchneriella subcapitata than for Daphnia magna and Lemna minor, which suggests an increased sensitivity of algae to acrylamide. According to the toxic unit approach, the values estimated by the Lemna minor and Daphnia magna bioassays, classify acrylamide as slightly toxic (TU=0-1; Class 1). The results obtained from algal bioassays (Desmodesmus subspicatus and Pseudokirchneriella subcapitata) revealed the toxic effect of acrylamide (TU=1-10; Class 2) on these organisms.

Acrylamide is a monomer widely used as an intermediate in the production of organic chemicals, e.g. polyacrylamides (PAMs). Since PAMs are low cost chemicals with applications in various industries and waste- and drinking water treatment, a certain amount of non-polymerised acrylamide is expected to end up in waterways. PAMs are non-toxic but acrylamide induces neurotoxic effects in humans and genotoxic, reproductive, and carcinogenic effects in laboratory animals. In order to evaluate the effect of acrylamide on freshwater organisms, bioassays were conducted on four species: algae Desmodesmus subspicatus and Pseudokirchneriella subcapitata, duckweed Lemna minor and water flea Daphnia magna according to ISO (International Organization for Standardisation) standardised methods. This approach ensures the evaluation of acrylamide toxicity on organisms with different levels of organisation and the comparability of results, and it examines the value of using a battery of low-cost standardised bioassays in the monitoring of pollution and contamination of aquatic ecosystems. These results showed that EC50 values were lower for Desmodesmus subspicatus and Pseudokirchneriella subcapitata than for Daphnia magna and Lemna minor, which suggests an increased sensitivity of algae to acrylamide. According to the toxic unit approach, the values estimated by the Lemna minor and Daphnia magna bioassays, classify acrylamide as slightly toxic (TU=0-1; Class 1). The results obtained from algal bioassays (Desmodesmus subspicatus and Pseudokirchneriella subcapitata) revealed the toxic effect of acrylamide (TU=1-10; Class 2) on these organisms., Akrilamid je monomer koji se koristi kao intermedijer u proizvodnji organskih kemikalija, npr. poliakrilamida (PAM-a). PAM se primjenjuje u različitim industrijama te u obradi otpadnih voda i tretmanu vode za piće, a prihvatljiv je i zbog niske cijene. Široka upotreba PAM-a u spomenute svrhe predstavlja rizik od toga da određena količina nepolimeriziranog akrilamida dospije u vodene ekosustave. PAM je netoksičan, ali akrilamid ima neurotoksične učinke u ljudi te je također dokazana njegova genotoksičnost, kancerogenost i štetan utjecaj na reprodukcijski sustav u laboratorijskih životinja. U cilju procjene toksičnosti akrilamida provedeni su biotestovi na četirima vrstama slatkovodnih organizama: na zelenim algama Desmodesmus subspicatus i Pseudokirchneriella subcapitata, vodenoj leći Lemna minor i vodenbuhi Daphnia magna. Biotestovi su provedeni prema standardiziranim ISO metodama, što osigurava procjenu toksičnosti akrilamida na organizme različitog stupnja organizacije, usporedivost rezultata i procjenu pogodnosti korištenja niza standardiziranih biotestova prihvatljive cijene za praćenje zagađenja i onečišćenja vodnih ekosustava. Rezultati su pokazali da su EC50 vrijednosti niže nakon izlaganja zelenih algi Desmodesmus subspicatus i Pseudokirchneriella subcapitata akrilamidu u odnosu na vrijednosti dobivene za vodenu leću Lemna minor i vodenbuhu Daphnia magna, što pokazuje veću osjetljivost algi. S obzirom na klasifikacijski sustav za izražavanje stupnja toksičnosti, a na temelju vrijednosti utvrđenih za vodenu leću Lemna minor i vodenbuhu Daphnia magna, akrilamid se može klasificirati kao slabo toksičan (TU=0-1; razred 1). Rezultati dobiveni testovima na algama (Desmodesmus subspicatus i Pseudokirchneriella subspicata) dokazuju toksičan učinak akrilamida na tim organizmima (TU=1-10; razred 2).

Acid mine drainage (AMD) is a by-product of the mining industry that has a detrimental effect on aquatic plant and animal life due to high load of heavy metals and sulfates. In the present study, the toxic and genotoxic potential of AMD prior to and following combination of neutralization/electrocoagulation processes was evaluated using several bioassays and selected parameters. Regardless of pH correction of AMD prior to Daphnia bioassay, high acute toxicity was observed in Daphnia magna. The mine leachate also induced strong phyto-, cyto- and genotoxicity to Allium cepa roots. Short term exposure to AMD inhibited duckweed growth and chlorophyll a content and simultaneously promoted lipid peroxidation and DNA damage despite duckweed capability to upregulate antioxidative defense mechanisms. The results show that observed (geno)toxicity could be related to oxidative stress most probably induced by toxic metal action. However, influence of low pH as a contributing factor in the phytotoxicity of AMD cannot be excluded. The application of combined treatment eliminated genotoxicity and was highly efficient in reducing toxicity of AMD. Thus, the method seems to be suitable for treatment of AMD waters enabling their safe discharge to an aquatic environment.

Aim was to determine whether uncontrolled disposal of food supplements into the environment, which in its composition contain magnesium (Mg), chromium (Cr), iron (Fe) and zinc (Zn) can cause unwanted effects on selected species of aquatic organisms as indicators of potential toxic effects of such preparations on the environment. Aquatic organisms: the freshwater algae Scenedesmus subspicatus and Raphidocelis subcapitata, great water flea Daphnia maga and duckweed Lemna minor, were exposed to Mg, Cr, Fe and Zn from food supplements by standardized methods. A total of 30 samples were analyzed for each individual micronutrient. The results are expressed as effective concentration 50 (EC50), i.e. the concentration of Mg, Cr, Fe and Zn (mg / L), which inhibits growth or immobilizes 50% of the treated organisms. EC50 metals significantly differ (p