The toxic effect of oxytetracycline and trimethoprim in the aquatic environment.
The objective of our study was the investigation of the toxic properties of two antimicrobial drugs: oxytetracycline (OTC) and trimethoprim (TMP) in the aquatic environment. The toxic effects were tested according to the OECD guidelines for the testing of chemicals, on the cyanobacteria Anabaena flos-aque, on the alga Pseudokirchneriella subcapitata, on the daphnid Daphnia magna as well as on the activated sludge. We discussed the short term and long term results of tests on cyanobacteria and microalgae. Both experiments were concluded in 72h allowing direct comparison of sensitivity of the two tested species. The results of our study showed toxic effect in the same range for both groups. In the test on the toxicity of OTC to P. subcapitata we obtained the 72hErC50 of 1.04mgL(-1) (72hErC10 0.47mgL(-1)) which are lower in comparison to the results on the toxicity to A. flos-aque of ErC50 of 2.7mgL(-1) (72hErC101.5mgL(-1)). TMP is less toxic to both photosynthetic plankton species. Similar to the test results on OTC, the P. subcapitata is more sensitive to TMP (ErC50129mgL(-1); ErC1065mgL(-1)) than A. flos-aque (72hErC50253mgL(-1); 72hErC1026mgL(-1)). OTC is toxic to the activated sludge (3hEC50 17.9mgL(-1)), while the calculated 3hEC50 value for TMP exceeded solubility for the compound. In comparison to other species, both tested antimicrobials showed low toxicity to daphnids.
National Laboratory of Health, Environment and Foodstuffs, Prvomajska 1, 2000 Maribor, Slovenia. Electronic address: boris.kolar@nlzoh.si.
Boris
B
Kolar
National Laboratory of Health, Environment and Foodstuffs, Prvomajska 1, 2000 Maribor, Slovenia.
Lovro
L
Arnuš
National Laboratory of Health, Environment and Foodstuffs, Prvomajska 1, 2000 Maribor, Slovenia.
Bogdana
B
Jeretin
National Laboratory of Health, Environment and Foodstuffs, Prvomajska 1, 2000 Maribor, Slovenia.
Aleš
A
Gutmaher
University of Ljubljana, Biotechnical Faculty, Department of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
Damjana
D
Drobne
National Laboratory of Health, Environment and Foodstuffs, Prvomajska 1, 2000 Maribor, Slovenia.
Mojca Kos
MK
Durjava
D000818:Animals; D000900:Anti-Bacterial Agents / Q000633:toxicity*; D000460:Chlorophyta / Q000187:drug effects* / Q000502:physiology; D003621:Daphnia / Q000187:drug effects* / Q000502:physiology; D046869:Dolichospermum flos-aquae / Q000187:drug effects* / Q000502:physiology; D010118:Oxytetracycline / Q000633:toxicity*; D014295:Trimethoprim / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D000900:Anti-Bacterial Agents; D014874:Water Pollutants, Chemical; D014295:Trimethoprim; D010118:Oxytetracycline
Activated sludge; Algae; Cyanobacteria; Oxytetracycline; Trimethoprim