Pharmaceuticals as Pollutants in the Aquatic Ecosystem – Cardiovascular, Anti-diabetic, Steroids and Related Drugs

Drugs like -blockers (atenolol, propranolol, metoprolol), ACE inhibitors (captopril, enalapril, lisinopril, ramipril, fosinopril, quinapril), angiotensin (AT1) receptor blockers (losartan, candesartan, valsartan, telmisartan), -blockers (prazosin, terazosin, doxazosin, phentolamine, phenoxybenzamine), central sympatholytics (clonidine, methyldopa), cardiac glycosides (digoxin, digitoxin), sympathetic drugs (adrenaline, dopamine, isoprenaline), anticholinergic drugs (atropine, scopolamine), xanthines (theophylline, theobromine), nitrates (glyceryl trinitrate, isosorbide dinitrate), calcium antagonists (verapamil, diltiazem) and K-channel openers (nicorandil) are used for the treatment of the cardiovascular disorder [1]. Recently a study was conducted on the occurrence of cardiovascular drugs in surface waters at a global scale. The study had 82 cardiovascular drugs out of which 58 (~71%) were detected at least once in the water bodies. The study also revealed that only 10% of the aquatic pollution was caused by the commonly prescribed antihypertensives (6% by angiotensin receptor-II antagonist and 4% by ACE inhibitors). The maximum contribution as a source of pollutants were from -blockers (atenolol, metoprolol, and propranolol) at 38% and 36% to lipid regulating agents (gemfibrozil, bezafibrate and clofibric acid). The ecotoxicity caused by these cardiovascular drugs was further limited to about 24%. The drugs that are a major risk to the aquatic organisms include propranolol, metoprolol, lipid regulating agents, bezafibrate, and atorvastatin. The partition coefficient (Log P) value of cardiovascular drugs ranges from 0.6 for atenolol to 7.7 for telmisartan that results in bioaccumulation in the environmental matrices. Based on the presence of cardiovascular drugs in the aquatic ecosystem, the water pollutants are divided into three major contaminants, municipal water, surface water, and drinking water.