The activity concentration of natural radionuclides 226 Ra, 232 Th and 40 K in vegetables and fruits in central zone of Malaysia were measured using gamma spectrometry. This is for the purpose of assessing the radiological risk in term of ingestion dose and cancer risk. The total ingestion dose from the consumption of vegetables were found to be 0.469 ± 0.003, 0.326 ± 0.005 and 0.232 ± 0.003 mSv/y for infants, children and adults respectively. Whereas the total ingestion dose from the consumption of fruits for infants, children and adults were 0.349 ± 0.005, 0.283 ± 0.007 and 0.195 ± 0.004 mSv/y respectively. The estimated cancer risk from the consumption of vegetables and fruits were 8.13 × 10 -4 and 6.83 × 10 -4 respectively for adults. The results obtained for activity concentration, dose and risk were found to be below the internationally recommended level. This indicates that the vegetables and fruits consumed in Malaysia would not pose any significant radiological impact to the population.Keywords: activity concentration, gamma spectrometry, ingestion dose, natural radionuclides, risk assesment Abstrak Kepekatan aktiviti radionuklid semulajadi 226 Ra, 232 Th and 40 K dalam sayur-sayuran dan buah-buahan di Malaysia bahagian tengah telah diukur menggunakan spektrometer gama. Ini bertujuan untuk menilai risiko radiologi dalam istilah dos dimakan dan risiko kanser. Didapati jumlah dos dimakan dari pengambilan sayur-sayuran adalah 0.469 ± 0.003, 0.326 ± 0.005 and 0.232 ± 0.003 mSv/tahun masing-masing bagi bayi, kanak-kanak dan dewasa. Manakala jumlah dos dimakan dari pengambilan buahbuahan bagi bayi, kanak-kanak dan dewasa adalah masing-masing 0.349 ± 0.005, 0.283 ± 0.007 and 0.195 ± 0.004mSv/tahun. Risiko kanser dari pengambilan sayur-sayuran dan buah-buahan bagi orang dewasa masing-masing dijangkakan sebanyak 8.13 × 10 -4 dan 6.83 × 10 -4 . Kesemua hasil yang diperolehi dalam kajian ini bagi kepekatan aktiviti, dos dan risiko didapati berada di bawah aras yang dibenarkan oleh badan antarabangsa. Ini menunjukkan bahawa sayur-sayuran dan buah-buahan yang diambil di Malaysia tidak menimbulkan bahaya radiologi yang ketara terhadap manusia.Kata kunci: kepekatan aktiviti, spektrometer gama, dos dimakan, radionuklid semula jadi, penilaian risiko
IntroductionThe total annual radiation dose received by a member of the population each year is 3.01 mSv. About 79.73% of this number is contributed by natural radiation sources (2.4 mSv/y) and the rest 20.27% by man-made radiation sources (0.61 mSv/y) [1]. It is clear that the natural radiation sources is the main contributor to the total annual radiation dose. One component of this natural radiation sources is the ingestion dose (0.29 mSv/y) that are mainly contributed by