The micronucleus frequency in cytokinesis-blocked lymphocytes of cattle in the vicinity of a nuclear power plant

Cytogenetic and hematological analyses were performed on the peripheral blood lymphocytes (PBLs) obtained from Korean native cattle bred in the vicinity of three nuclear power plants (Wolsong, Uljin and Yeonggwang) and in a control area. The micronucleus (MN) rates for the cattle from the Wolsong, Uljin and Yeonggwang nuclear power plants and for the control area were 9.87 +/- 2.64, 8.90 +/- 3.84, 9.20 +/- 3.68 and 9.60 +/- 3.91 per 1,000 cytokinesis-blocked lymphocytes, respectively. The apparent difference is not statistically significant. The MN frequencies of PBLs from cattle bred in the four areas are within the background variation for this study. The MN frequencies and hematological values were similar regardless of whether the cattle were bred near a nuclear power plant or in the control area.

Annual background radiation in Chaharmahal and Bakhtiari province

Measurement of background radiation is very important from different points of view especially for human health. The aim of this survey was focused on determining the current background radiation in one of the highest altitude regions [Zagros Mountains], Chaharmahal and Bakhtiari province, in the south west of Iran. Materials and The outdoors-environmental monitoring exposure rate of radiation was measured in 200 randomly chosen regions using portable Geiger-Muller and Scintillation detectors. Eight measurements were made for each region and an average value was used to calculate the exposure rate from natural background radiation. The exposure dose rate was found to be 28.4 m Rh-1 and the annual average effective equivalent dose was found to be 0.49 mSv. An overall population weighted average outdoor dose rate was calculated to be 49 nGyh-1, which is higher than the world-wide mean value of 44 nGyh-1 and is comparable to the annual effective equivalent dose of 0.38 mSv. A good correlation between the altitude and the exposure rate was observed, as the higher altitude regions have higher natural background radiation levels

90Sr-90Y biokinetics at incorporation determine the radiation burden to bone marrow.

The decay characteristics of 90Sr-90Y ensure that the mother and daughter nuclides exist in radioactive equilibrium, unless they get discriminated on the basis of their chemical properties, as it happens during metabolism. Although bone is the ultimate organ of deposition, the two nuclides arrive at this target organ over different biokinetic pathways. As 90Y is not excreted, it goes through transient deposition in the liver before being secondarily deposited in bone. This leads to a temporary radioactive excess of 90Y in bone. Since the decay energy of 90Y is by a factor of about 4 higher than that of 90Sr, the initial radiation burden to the bone marrow is primarily due to 90Y. This was estimated in rats by implanting LiF thermoluminescence dosimeters (TLD) in the marrow cavity of the femur. By calibrating the TLD against a known source of 90Sr-90Y, the absorbed dose rates and cumulative doses were determined as a function of time after incorporation. Two routes of administration were employed and their influence on the radiation burden is also shown.

Agenda XXI: Cumbre de la tierra - v.2 / Notebook XXI: Earth summit - v.2

El documento Agenda XXI, tomo II, de la Cumbre de la Tierra; contiene los siguientes capítulos: 15)Conservación de la diversidad biológica, 16)Gestión ecológicamente racional de la biotecnología, 17)Protección de los océanos y de los mares de todo tipo, incluídos los mares cerrados y semicerrados, y de las zonas costeras, y protección, utilización racional y desarrollo de sus recusos vivos, 18)Protección de la calidad y el suministro de los recursos de agua dulce. Aplicación de criterios integrados para el aprovechamiento, ordenación y uso de los recursos de agua dulce, 19)Gestión ecológicamente racional de los productos químicos tóxicos incluída la prevención del tráfico internacional ilícito de productos tóxicos y peligrosos, 20)Gestión ecológicamente racional de los desechos sólidos y cuestiones relacionadas con las aguas cloacales, 22)Gestión inocua y ecológicamente racional de los desechos radiactivos