title: Estimation of external dose by car-borne survey in Kerala, India.
abstract: A car-borne survey was carried out in Kerala, India to estimate external dose. Measurements were made with a 3-in × 3-in NaI(Tl) scintillation spectrometer from September 23 to 27, 2013. The routes were selected from 12 Panchayats in Karunagappally Taluk which were classified into high level, mid-level and low level high background radiation (HBR) areas. A heterogeneous distribution of air kerma rates was seen in the dose rate distribution map. The maximum air kerma rate, 2.1 μGy/h, was observed on a beach sand surface. 232Th activity concentration for the beach sand was higher than that for soil and grass surfaces, and the range of activity concentration was estimated to be 0.7-2.3 kBq/kg. The contribution of 232Th to air kerma rate was over 70% at the measurement points with values larger than 0.34 μGy/h. The maximum value of the annual effective dose in Karunagappally Taluk was observed around coastal areas, and it was estimated to be 13 mSv/y. More than 30% of all the annual effective doses obtained in this survey exceeded 1 mSv/y.
authors.affiliation: Hirosaki University Graduate School of Health Sciences, Aomori, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hosoda
authors.affiliation: Institute of Radiation Emergency Medicine, Hirosaki University, Aomori, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Tokonami
authors.affiliation: Fukushima Medical University, Fukushima, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Omori
authors.affiliation: National Institute of Radiological Sciences, Chiba, Japan.
authors.forename: Sarata Kumar
authors.initials: SK
authors.lastname: Sahoo
authors.affiliation: Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
authors.forename: Suminori
authors.initials: S
authors.lastname: Akiba
authors.affiliation: Fukushima Medical University, Fukushima, Japan.
authors.forename: Atsuyuki
authors.initials: A
authors.lastname: Sorimachi
authors.affiliation: Fukushima Medical University, Fukushima, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Ishikawa
authors.affiliation: Regional Cancer Center, Kerala, India.
authors.forename: Raghu Ram
authors.initials: RR
authors.lastname: Nair
authors.affiliation: Natural Background Radiation Cancer Registry, Kerala, India.
authors.forename: Padmavathy Amma
authors.initials: PA
authors.lastname: Jayalekshmi
authors.affiliation: Regional Cancer Center, Kerala, India.
authors.forename: Paul
authors.initials: P
authors.lastname: Sebastian
authors.affiliation: Institute of Radiation Emergency Medicine, Hirosaki University, Aomori, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Iwaoka
authors.affiliation: National Institute for Fusion Science, Gifu, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Akata
authors.affiliation: Hirosaki University Graduate School of Health Sciences, Aomori, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Kudo
mesh_terms: D001336:Automobiles; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods*; D006801:Humans; D007194:India; D011829:Radiation Dosage; D011868:Radioisotopes / Q000032:analysis*; D011795:Surveys and Questionnaires
chemical_list: D011868:Radioisotopes