Bayrak, KübraYümün, Zeki ÜnalÇakar, Merve Melodi2022-05-112022-05-1120202148-26832148-2683https://doi.org/10.31590/ejosat.686668https://app.trdizin.gov.tr/makale/TXpZek1EYzVPUT09https://hdl.handle.net/20.500.11776/6187Radioactivity measurements were performed, at the Yalova (Turkey), part of the Marmara Sea, for natural radiation using ascintillation detector SP6 (via using portable counter ESP2, Eberline). Based on the measurement results, the lowest outdoor gammaconcentration was calculated to 27.70 nGy/h while the highest one calculated to 66.00 nGy/h. And, the average of the measuredgamma dose rates calculated to 48.13 nGy/h while the annual effective dose equivalent was calculated to 59.02 ?Sv/y. Mean value ofexcess lifetime cancer risk also obtained 2.07 $10^{-4}$from using measurement area. The results checked against the world averagedetermined by UNSCEAR. It was concluded that the calculated gamma dose values in Yalova are below the world average.en10.31590/ejosat.686668info:eu-repo/semantics/openAccessArticle018568573TXpZek1EYzVPUT09