ABSTRACT
Produced, consumed and globally released into the environment in considerable quantities, artificial sweeteners have been identified as emerging pollutants. Studies of environmental concentrations have confirmed the widespread distribution of acesulfame (ACE), cyclamate (CYC), saccharin (SAC) and sucralose (SUC) in the water cycle at levels that are among the highest known for anthropogenic trace pollutants. Their ecotoxicity, however, has yet to be investigated at a larger scale. The present study aimed to fill this knowledge gap by systematically assessing the influence of ACE, CYC and SAC and complementing the data on SUC. Therefore we examined their toxicity towards an activated sewage sludge community (30min) and applying tests with green algae Scenedesmus vacuolatus (24h), water fleas Daphnia magna (48h) and duckweed Lemna minor (7d). We also examined the effects caused by the natural sweetener stevioside. The high No Observed Effect Concentrations (NOECs) yielded by this initial evaluation indicated a low hazard and risk potential towards these aquatic organisms. For a complete risk assessment, however, several kinds of data are still lacking. In this context, obligatory ecotoxicity testing and stricter environmental regulations regarding food additives appear to be necessary.
Subject(s)
Daphnia/drug effects , Magnoliopsida/drug effects , Scenedesmus/drug effects , Sweetening Agents/toxicity , Water Pollutants, Chemical/toxicity , Animals , Aquatic Organisms/drug effects , Chlorophyta/drug effects , Diterpenes, Kaurane/toxicity , Ecotoxicology/methods , Glucosides/toxicity , Sewage/chemistry , Sweetening Agents/chemistry , Sweetening Agents/classificationABSTRACT
Doramectin (DOR), metronidazole (MET), florfenicol (FLO), and oxytetracycline (OXT) are among the most widely used veterinary drugs in animal husbandry or in aquaculture. Contamination of the environment by these pharmaceuticals has given cause for concern in recent years. Even though their toxicity has been thoroughly analyzed, knowledge of their ecotoxicity is still limited. We investigated their aquatic toxicity using tests with marine bacteria (Vibrio fischeri), green algae (Scenedesmus vacuolatus), duckweed (Lemna minor) and crustaceans (Daphnia magna). All the ecotoxicological tests were supported by chemical analyses to confirm the exposure concentrations of the pharmaceuticals used in the toxicity experiments, since deviations from the nominal concentration can result in underestimation of biological effects. It was found that OXT and FLO have a stronger adverse effect on duckweed (EC50=3.26 and 2.96mgL(-1) respectively) and green algae (EC50=40.4 and 18.0mgL(-1)) than on bacteria (EC50=108 and 29.4mgL(-1)) and crustaceans (EC50=114 and 337mgL(-1)), whereas MET did not exhibit any adverse effect in the tested concentration range. For DOR a very low EC50 of 6.37×10(-5)mgL(-1) towards D. magna was determined, which is five orders of magnitude lower than values known for the toxic reference compound K2Cr2O7. Our data show the strong influence of certain veterinary drugs on aquatic organisms and contribute to a sound assessment of the environmental hazards posed by commonly used pharmaceuticals.
Subject(s)
Aliivibrio fischeri/drug effects , Araceae/drug effects , Chlorophyta/drug effects , Daphnia/drug effects , Environmental Pollutants/toxicity , Veterinary Drugs/toxicity , Animal Husbandry , Animals , Araceae/growth & development , Chlorophyta/physiology , Daphnia/physiology , Environmental Pollutants/chemistry , Ivermectin/analogs & derivatives , Ivermectin/chemistry , Ivermectin/toxicity , Metronidazole/chemistry , Metronidazole/toxicity , Oxytetracycline/chemistry , Oxytetracycline/toxicity , Reproduction/drug effects , Thiamphenicol/analogs & derivatives , Thiamphenicol/chemistry , Thiamphenicol/toxicity , Veterinary Drugs/chemistryABSTRACT
The (eco)toxicity of the most common ionic liquid anions like [N(CN)(2)](-), [C(CN)(3)](-), [B(CN)(4)](-), [(CF(3)SO(2))(2)N](-), [(C(2)F(5))(3)PF(3)](-) was investigated in test systems of different trophic level. In the same order, and thus with increasing hydrophobicity, a trend of higher toxicity was found. Especially the [(C(2)F(5))(3)PF(3)](-) moiety poses a significant hazard towards aquatic organisms.
ABSTRACT
This paper reports on the (eco)toxicity and biodegradability of ionic liquids considered for application as lubricants or lubrication additives. Ammonium- and pyrrolidinium-based cations combined with methylsulphate, methylsulphonate and/or (CF(3)SO(2))(2)N(-) anions were investigated in tests to determine their aquatic toxicity using water fleas Daphnia magna, green algae Selenastrum capricornutum and marine bacteria (Vibrio fischeri). Additional test systems with an isolated enzyme (acetylcholinesterase) and isolated leukaemia cells from rats (IPC-81) were used to assess the biological activity of the ionic liquids. These compounds generally exhibit low acute toxicity and biological activity. Their biodegradability was screened according to OECD test procedures 301 B and 301 F. For choline and methoxy-choline ionic liquids ready biodegradability was observed within 5 or 10 d, respectively. Some of the compounds selected have a considerable potential to contribute to the development of more sustainable products and processes.
