Continuous monitoring of chemicals in the environment is important to control their fate and to protect human health, flora, and fauna. Perfluoroalkyl acids (PFAAs) have been detected frequently in different environmental compartments during the last 15 years and have drawn much attention because of their environmental persistence, omnipresence, and bioaccumulation potential. Water is an important source of their transport. In the present study, distributions of PFAAs in river water, wastewater treatment plant (WWTP) effluent, and tap water from eastern part of Germany and western part of Kenya were investigated. Eleven perfluorocarboxylic acids (PFCAs) and five perfluorosulfonic acids (PFSAs) were analyzed using liquid chromatography/tandem mass spectrometry. Sum of mean concentrations of eight PFAAs detected in drinking tap water from Leipzig was 11.5 ng L-1, dominated by perfluorooctanoic acid (PFOA, 6.2 ng L-1). Sums of mean riverine concentrations of PFAAs detected in Plei beta e/White Elster, Saale, and Elbe (Germany) were 24.8, 54.3, and 26.8 ng L-1, respectively. Annual flux of PFAAs from River Saale was estimated to be 164 +/- 23 kg a(-1). The effluent of WWTP in Halle was found to contain four times higher levels of PFAAs than river water and was dominated by perfluorobutane sulfonate (PFBS) with 32 times higher concentration than the riverine level. It advocates that WWTPs are the point source of contaminating water bodies with PFAAs, and short-chain PFAAs are substituting long-chain homologues. Sums of mean riverine concentrations of PFAAs in Sosiani (Kenya) in samples from sparsely populated and densely populated areas were 58.8 and 109.4 ng L-1, respectively, indicating that population directly affected the emissions of PFAAs to surface waters. The discussion includes thorough review and comparison of recently published literature reporting occurrence of PFAAs in aqueous matrices.