[en] Radioecology or the study of the relationship between living things and radioactive environments becomes important in order to understand and predict environmental impact and to safeguard populations from any hazard arising from radioactive discharge. Assessment of transfer coefficients, soil plant transfer factors, field experiments, transfer factors in the aquatic and marine ecosystem and modeling of environmental transfer are fully discussed. The future trends and needs of radioecology are given. (ELC)

[en] This review was conducted to determine the minimum dose of radioactive iodine necessary to show signs and symptoms of thyrotoxicosis among Filipinos, to determine the incidence of hypothyroidism secondary to radioactive treatment and to determine if some cases of hypothyroidism following radioactive iodine treatment are only transient and replacement therapy could be withheld or not. A total of 212 patients who had I-131 therapy was evaluated (177 female and 35 male). Of this number 19 or 8.9% developed hypothyroidism. After three years, 14 or 74% of the hypothyroids were noted. Easy fatigability ranked first of the patients complaints, followed by dry skin, sleepiness, numbness of extremities, and joint pains. Results of this study indicate that there is a definite, although low incidence of hypothyroidism following I-131 therapy (8.9%). (ELC). 6 refs.; 6 tabs

[en] Content analysis of media coverage of nuclear news provides an estimate of public awareness of nuclear power necessary for decision making. Issues raised suggest the extent of public perception and concern that may influence formation of attitudes towards the use of nuclear energy for power generation. A standard procedure for media content analysis developed by the International Atomic Energy Agency (IAEA) is utilized in this study. Releases on nuclear power from major Philippine newspapers were analyzed. The article prominence, amount of reported dissent and consent relative to nuclear power, the tendency of each news item to influence positive or negative public attitudes towards nuclear power and the nuclear issues mentioned in the articles were determined and statistically analyzed. Results provide insights into the importance of the role of mass media in disseminating technical and scientific information primarily towards generating general impressions, and ultimately leading to attitude formation. (author)

[en] A greenhouse experiment was conducted using two sulfur (S) deficient soils to evaluate the effect of pre-planting moisture regime and two S sources on the growth, yield and uptake of rice. The two S deficient soils used were a Tropic Vertic Flusoquent from San Juan, Batangas and a Seric Tropaquent from Sta Maria, Pangasinan. Pre submergence and non-presubmergence of soil two weeks before transplanting were the pre-planting moisture regimes employed. (NH₄)₂³⁵SO₄(AS) and urea ³⁵S(US) were the S sources applied at the rate of 20ppm S. ³⁵S-tagged fertilizers were used to determine the utilization of each fertilizer source by rice plant and fate of added S in flooded soil. The application of S significantly enhanced all plant parameters in both soils. However, the response to S was quite marked in San Juan soil than in Sta Maria despite the fact that both soils have the same amount of available S initially and the San Juan soil has more total S content than Sta Maria. The pre-planting moisture regimes did not have significant influence on plant height, tiller number and yield (grain and straw) of rice in soils added with S either as AS or US. Added S significantly increase S uptake by rice in both soils. No significant differences in S uptake was obtained between the pre-planting moisture regimes and between the S sources in Sta Maria. However, lower S uptakes in grain and straw were obtained from AS than US in San Juan. Moreover, a significant reduction in S uptake in grain was observed when the San Juan soil was pre-submerged and applied with AS but not with US. Percent utilization of S from AS by the rice plant was significantly higher than that from US at maturity. Percent utilization of applied S was generally higher in San Juan than in Sta Maria. (Auth.). 13 refs., 9 tabs., 2 figs

[en] The study attempts to determine the total population and population growth rates of four (4) age groups per municipality/city within twenty (20), fifty (50) and eighty (80) kilometers from the Philippine Nuclear Power Plant (PNPP-1). The population estimates were done at five (5) year intervals covering the next fifty years. The latest National Census and Statistics Office (NCSO) population projections at the provincial level under the assumption of moderate fertility and moderate mentality decline (series no. 2) were used to derive the estimates of the total population and population growth rates at the minicipality/city levels. The Bureau of Coastal and Geodetic Survey (BCGS) and the NCSO maps served as the bases for delineating the geographic and political boundaries covered by the study. The results will complement the findings of the PAEC project on agricultural parameters for radiation dose calculations and useful for related environmental studies. (author)

[en] This paper is a result of the greenhouse experiments conducted on micronutrient studies in corn. Low yields of corn in some localities despite the application of major elements points out the need for examining the micro-nutrient requirements of corn. Hence, this study aims to determine the fate of added micronutrients on major soil groups with the application of varying levels of nitrogen, phosphorus, and potassium to provide the better understanding of soil micronutrients especially in problem soil. Three soil types, four N-P-K treatments and two micronutrients (Zn and Fe) were used. The test crop was a Tinigib corn variety and sampled at tasseling and silking stages. It was found that NPK combinations of 120-60-30 kg/ha and 60-30-30 kg/ha gave better Fe and Zn fertilizer use efficiency, respectively for a given soil type. Further investigation in major soil types is recommended. (Auth.) 12 refs.; 9 tabs

[en] The paper outlines the procedure for the calculation of protection factors and gives values for some typical hollow block structures in local rural communities. Some discussions are given on the effect of the position of the receptor in these structures. (Auth.) 7 refs.; 4 tabs

[en] Decomposition patterns of ¹⁴C-labelled rice straw were studied, both in the field and in the laboratory. While anaerobic decomposition of straw in laboratory experiment was highly retarded, decomposition rates in submerged field were as high as under aerobic conditions. It is suggested that enhanced decomposition in submerged fields is caused by a very high activity and diversity of soil edaphon. Especially, nitrogen availability seems to be mainly dependent on soil biomass production and its turnover. Following the decomposition pattern in the field. A decay-accumulation series was used to relate soil carbon contents and seasonal carbon amendments. Based on long term yield experiments, a relationship between soil nitrogen, N-fertilizer and rice yields was established. (Author). 22 refs., 10 figs., 2 tabs

[en] Thermoluminescent dosimeters were used as detectors to measure natural background radiation levels in 10 provinces throughout the Philippines. These dosimeters were deployed in densely populated areas. The average dose rate for outdoor and indoor exposures were 4.41 μR h^-1 and 4.52 μR h^-1 respectively. External radiation measurements (outdoors) were also conducted in these 10 provinces using a Studsvik gammameter which gave an average outdoor exposure dose rate of 4.40 μR h^-1. (Auth.). 7 refs.; 3 figs.; 3 tabs

[en] This study was undertaken to determine the radioactivity levels around the vicinities of NPC's geothermal power plants. Qualitative and quantitative determination of significant radionuclides of geothermal origin was made and the releases were found to be within acceptably safe levels. It was also established that no radiological health hazard exists for the power plant personnel and the residents within 30-km radius from the plant. (Auth.). 5 tabs., 4 figs., 7 refs