Occurence of beta-blockers and calcium channel blockers in aquatic environment and their influence on fish

The aim of this bachelor thesis was to make an overview of distribution of beta-blockers and calcium channel blockers, their occurrence in aquatic environment and their impact on fish. Analysis of data obtained from the website of the State Instiute for Drug Control, which was carried out in Excel revealed, that 53 643 kilograms of beta-blockers and 24 472 kilograms of calcium channel blockers was distributed in the Czech Republic in 2011. Metoprolol, acebutlol and atenolol reached the largem volume of distribution among aktive ingredients in the group of beta-blockers. Verapamil, amlodipin and diltiazem were TOP 3 calcium channel blockers. These drugs are generally the most sold in the world and they can be found in surface waters in the Czech Republic and worldwide at concentrations rating from tens to hundreds ng.l-1 . The reason for this is the low removal rate of beta-blockers and calcium channel blockers in wastewater treatment plants, which ranges from 11 to 76%. Toxicity tests on fish with metoprolol, propranolol, atenolol, verapamil and diltiazem have shown the effect of this pharmaceuticals on e.g., reduction of fecundity, hatchability or heart rate. Various histopatological changes on the liver and heart or malformations of early developmental stages of fis have been also reported. The lowest concentrations of the tested substances at which these effects were observed, ranged mostly from values g.l-1 to mg.l-1, i.e. these concentrations were higher than those commonly found in surface waters. However, some effects were observed also at environmentally relevant concentrations. Due to prolong-term exposure on the organisms beta-blockers and calcium channel blockers may represent a threat to aquatic ecosystems. A solution could be to improve the mechanism for removal of pharmaceuticals in the sewage treatment plants