2012 about 1,200 pharmaceutical substances were identified to be potentially relevant for an environmental monitoring. effects of pharmaceuticals in the environment further information: environmental impact of pharmaceuticals and personal care products estradiol (estrogen, synthetic hormone) concentrations in surface water alone are not sufficient to assess the risk of negative environmental effects in the aquatic environment. synthetic hormones are endocrine disruptors. thus, estrogenic compounds like ethinylestradiol (estrogen hormone) at concentrations < 1 ng per litre may cause both vitellogenin production (a frequently used index for feminization of male fish), and structural change in their sex organs. it has also been demonstrated that fish exposed to sewage treatment plant (stp) effluent can take up and concentrate estrogenic compounds, including ethinylestradiol, to very high internal levels. these observations on feminization of fish by estrogenic compounds in stp effluents have been observed in many countries, and have also been observed in other species, like frogs, alligators and molluscs. cardiovascular medicines other examples of environmental impact in the aquatic environment of human medication concern both cardiovascular and neuro-psychiatric medicines. the non-selective beta-blocking agent propanolol was found to cause a significant decrease in egg production in medaka fish, at a concentration close to that demonstrated in the sewage treatment plants (stp) effluents. gemfibrozil (cholesterol and triglycerides lowering drug) often appears in the effluent from stps. at concentrations close to those reported in stp effluent, gemfibrozil lowers the blood levels of testosterone in fish. citalopram / fluoxetine (serotonin reuptake inhibitor anti depressants, ssris) some ssris have been shown to accumulate in exposed fish. citalopram has been detected in liver from wild perch in low µg per kg levels, and fluoxetine affects the serotonin system in the same way that it does in humans. fluoxetine has also been shown to affect swimming activity in shellfish; whether this is linked to a disturbance of serotonin function in the brain is still unknown. antibiotics high levels of antibiotics in the water are a cause for alarm as there is an increased risk of selecting resistant bacteria, an issue of global concern. this can lead to some highly effective antibiotics becoming ineffective. there are several examples: in india, bacteria resistant to ciprofloxacin have been found downstream pharmaceutical plants, genes for multi resistance were found in drinking water, and multi resistant salmonella in water sprayed on vegetables. from europe we know about the epidemic with multi resistant ehec in summer 2011, originating from water sprayed vegetables. the term "eco-shadow" has been introduced to describe the ecological impact of antibiotics. antibiotics with a wide spectrum that are also stable will have a greater impact on the bacterial flora (a long eco-shadow) than those with a narrow antibacterial spectrum which disintegrates more rapidly (a short eco-shadow). the ecological effects of tetracyclines and quinolones have been observed. they are not metabolized in the human body and are therefore excreted unmodified. when entered into the environment they are poorly degraded. they can be toxic to other animals, affecting particularly microorganism and fish. in the effluent from a sewage treatment plant in india, several broad spectrum antibiotics were found in concentrations toxic to bacteria and plants. in the sewage treatment plant itself, there were enterococcae resistant to all known antibiotics. the development of resistant bacteria in sewage treatment plants is stimulated by high concentration of antibiotics (e.g. in plant sewage), large amounts of bacteria (e.g. from human sewage water that is added in plant sewage), and selection of information that can be used to assess the nominated issue have been observed. gaps in knowledge effective environmental detection methods have to be developed and global detection strategy applied to map the current global situation. there are currently no test methods to assess whether negative effects may occur after long-term environmental diffuse exposure in humans, during the vulnerable periods of development, on aquatic micro-organism or how it may affect other animals. therefore, the precautionary principle must be guiding. concentrations in surface water alone are not sufficient to assess the risk of negative environmental effects of these synthetic chemicals. consideration must be taken to bio-accumulation in fish and other aquatic food used by humans, as well as to additive and synergetic effects between pharmaceutical and other chemicals in the contaminated water. in a small study, several pharmaceuticals were found in milk of goat, cow and human. more research is needed to find out how common this is, the concentrations and the sources.