Efficiency of Nitrifying and Denitrifying Bacteria in Removing Micropollutants in Water Samples Jaqueline Souza & Terencio Rebello de Aguiar Junior Received: 12 January 2020 /Accepted: 12 March 2020 # Springer Nature Switzerland AG 2020 Abstract Several regions of the world have been suf- fering from problems of water quality degradation caused mainly by the input of nutrients such as nitrogen and phosphorus, resulting from anthropic activities. In excess, these nutrients can be considered micropollutants that could be responsible for the blooms of aquatic plant species, algae, and potentially toxic cyanobacteria, resulting in the interference of water quality in the socio-economic and environmental sector. Biological mitigation measures using specific microor- ganisms have been applied for the removal of micro pollutants due to their high efficiency of nitrogen and phosphorus. The present study analyzed the efficiency of nitrifying bacteria such as N. europaea and N. winodradskyi and P. denitrificans denitrifying bacte- ria, individually and as a bacterial pool (formed by N. europaea, N. winodradskyi, and P. denitrificans), in removing NH 3 , NO 2 - , NO 3 - , N, P, and PO 4 3- , in pure water samples at times 0 to 1440 min and 0 to 7200 min. N. europaea and N. winodradskyi presented 100% removal efficiency for compounds NH 3 and NO 2 - re- spectively, and bacterial pool removed 100% of com- pounds NO 2 - and P at time 1440 min (24 h). At time 7200 min (120 h), P. denitrificans obtained 100% re- moval of NO 2 - and NO 3 - . Over time, the bacterial pool obtained 100% removal for all compounds analyzed in the present study. This paper demonstrated the excellent performance of microorganisms in the removal of nitro- gen and phosphorus compounds in pure water samples. Keywords Micropollutant removal . Nitrogen . Phosphorus . Nitrifying bacteria 1 Introduction One of the main aggravating factors related to water resources worldwide is the degradation of water quality, as it causes several problems to human health, the aquatic ecosystem, the commitment of human supply water sources, and the intensification of the water scar- city scenario (Ribeiro and Rolim 2017; Vryzas 2018). Several countries of the world like Australia, China, and the USA have been suffering from problems of water quality degradation caused mainly by anthropo- genic activities due to the discharge of domestic sewage, industrial effluents and agricultural activities (Burford et al. 2007; Te and Gin 2011; Ndlela et al. 2016; Wang and Yang 2016; Wang et al. 2019; Yuan et al. 2019; Dou et al. 2019). These activities cause the input of nutrients such as nitrogen and phosphorus into the aquatic envi- ronment, that in excess can be considered as Water Air Soil Pollut (2020) 231:180 https://doi.org/10.1007/s11270-020-04523-z Highlights • Biological treatment is an effective way to remove micropollutants. • Bacteria efficiency is related to contact time with nitrogen and phosphorus. • Bacterial pool removes 100% of nitrogen and phosphorus. • The bacteria can be applied as water micro pollutant remediators. J. Souza (*) : T. R. de Aguiar Junior Department of Environmental Engineering, Federal University of Bahia (UFBA), Polytechnic School, Rua Professor Aristídes Novis, 2, Salvador, Bahia, Brazil e-mail: engambientaljaqueline@gmail.com