Radionuclide transfer to fruits: A critical review. Foreword

After completion of the (Validation of Environmental Model Predictions) (VAMP) and (BIOspheric Model Validation Study) (BIOMOVS II) Programmes, the Division of Radiation and Waste Safety of the IAEA decided to promote a new co-ordinated research programme to continue activities in the area of biosphere modelling. As a result, the BIOMASS Programme on BIOsphere Modelling and ASSessment was launched in Vienna in October 1996. The Programme is scheduled to finish in October 2000. The overall objective of BIOMASS is to provide an international focal point in the area of biosphere assessment modelling. There are 3 Themes and 11 working groups in BIOMASS. The objective of the Theme 3 Fruits Working Group is to improve understanding of the uptake and transfer of radionuclides from different sources to fruit. As part of the work programme, a review was undertaken of the experimental, field and modelling information on the transfer of radionuclides to fruit.     

Exploring decentralized forest management in Ethiopia using actor-power-accountability framework: case study in West Shoa zone

Decentralized forest management is a pivotal approach in Ethiopia for balancing biodiversity conservation with demand for economic development, and for improving forest-dependent local peoples’ livelihoods. With the aim of filling the literature gap on Ethiopia, this paper explores the dynamics of decentralization in the forestry sector using the actor-power-accountability framework. Generally, three forms of decentralization are practiced: deconcentration to government administrative branches, devolution of selected decision-making power to local people, and delegation to enterprises. Although transfer of meaningful discretionary power to local people or to downwardly accountable lower-tier governments is a precondition for achieving positive outcomes from decentralization, this prerequisite has been realized in none of the three forms decentralization. Overall, three important trends emerged from the latest decentralization reform, which was a switch from the conservation-oriented deconcentration form of decentralization to the income generation-oriented delegation form of decentralization. Those trends are as follows: monetary income generation for local people through enterprise, albeit with possible risk of being deprived of income and subsistence opportunities on which local people depend for their livelihoods; moving decision-making power away from the grassroots; and lack of incentive to manage natural forests, a major source of biodiversity.     

Effect of dietary protein on the distribution of cadmium,zinc and copper in rats following the oral administration of cadmium

Cadmium, 100 μg/rat/day, was administered orally 100 times (total amount of Cd administered, 10 mg), under conditions of low protein intake. The total amount of Cd in the liver and kidneys was as follows: females fed 20% protein diets > females fed 5% protein diets > males fed 20% protein diets ≒ males fed 5% protein diets. A decreased Zn concentration was found in the liver of males and the pancreas of males and females fed with the 5% protein diet. The Cu concentration in the kidneys was markedly influenced by low protein intake.     

Dynamics of the nitrogen cycle in a lake and its stability

Recent eutrophication of lakes or sea water has caused serious damage to the ecological balance in aquatic systems and to the quality of water for human use. The purpose of this study is to construct a dynamic model of the nitrogen cycle in a lake and to study the dynamic behavior of the various nitrogen forms such as organic, inorganic and plankton in connection with the mechanism of algal blooms in lakes. The dynamics of the system are represented by a system of non-linear differential equations which include the predator-prey relation between plankton types, and are discussed with the stability analysis of the critical points of differential equations. The effects of seasonal changes of environmental parameters are studied with computer simulations.     

Mutagenicity of anaerobic fenitrothion metabolites after aerobic biodegradation

Previous studies have revealed that the mutagenicity of fenitrothion increases during anaerobic biodegradation, suggesting that this insecticide's mutagenicity could effectively increase after it pollutes anaerobic environments such as lake sediments. To investigate possible changes to the mutagenicity of fenitrothion under aerobic conditions after it had already been increased by anaerobic biodegradation, batch incubation cultures were maintained under aerobic conditions. The mutagenicity, which had increased during anaerobic biodegradation, decreased under aerobic conditions with aerobic or facultative bacteria, but did not disappear completely in 22 days. In contrast, it did not change under aerobic conditions without bacteria or under continued anaerobic conditions. These observations suggest that the mutagenicity of anaerobically metabolized fenitrothion would not necessarily decrease after it arrives in an aerobic environment: this would depend on the presence of suitable bacteria. Therefore, fenitrothion-derived mutagenic compounds may pollute the water environment, including our drinking water sources, after accidental pollution of aerobic waters. Although amino-fenitrothion generated during anaerobic biodegradation of fenitrothion was the principal mutagen, non-trivial contributions of other, unidentified metabolites to the mutagenicity were also observed.     

Seasonal variations in 228Ra/226Ra ratio within coastal waters of the Sea of Japan: implications for water circulation patterns in coastal areas

In this study, low-background gamma-spectrometry was used to determine the (228)Ra/(226)Ra ratio of 131 coastal water samples from various environments around Honshu Island, Japan (mainly around Noto Peninsula) at 1-3 month intervals from April 2003 until September 2005. Spatial variation in (228)Ra/(226)Ra ratios was also assessed by analyzing 34 coastal water samples from five areas within the Sea of Japan during May and June 2004. The (228)Ra/(226)Ra ratio of coastal water from all sites around Noto Peninsula shows seasonal variation, with minimum values during summer ((228)Ra/(226)Ra=0.7) and maximum values during autumn-winter ((228)Ra/(226)Ra=1.7-2). This seasonal variation is similar to that recorded for coastal water between Tsushima Strait and Noto Peninsula. The measured lateral variation in (228)Ra/(226)Ra ratios within coastal water between Tsushima Strait and Noto Peninsula is only minor (0.5-0.7; May-June 2004). Coastal waters from two other sites (Pacific shore and Tsugaru Strait, north Honshu) show no clear seasonal variation in (228)Ra/(226)Ra ratio. These measured variations in (228)Ra/(226)Ra ratio, especially the temporal variations, have important implications for seasonal changes in patterns of coastal water circulation within the Sea of Japan.     

Determination of chlorine in air with the pyridine-pyrazolone reagent

An improved method for the determination of chlorine in air is described. The principle of this method is based on the absorption of chlorine in p-toluenesulfonamide aqueous solution, followed by color development with a pyridine-pyrazolone reagent. Both the chlorine absorbed in the solution and the color developed with the reagent were stable. Positive interference by nitrogen dioxide was not observed.     

Specific accumulation of polychlorinated biphenyls and organochlorine pesticides in Japanese common squid as a bioindicator

Organochlorines (OCs) representing Persistent Organic Pollutants (POPs) such as PCBs (polychlorinated biphenyls), DDTs (DDT and its metabolites), CHLs (chlordane compounds), HCHs (hexachlorocyclohexane isomers) and HCB (hexachlorobenzene) were determined in the liver of Japanese common squid (Todarodes pacificus) collected from the waters around Japan (Japan Sea and western North Pacific Ocean). Among OCs concentrations, PCBs (upto 5600 ng/g lipid wt.) were the highest, and those of other OCs were in the order of DDT> CHLs > HCHs > HCB. Studies on growth trend and seasonal variation of OCs in this species suggest a rapid reflection of the pollution levels in seawater where and when they were collected, regardless of body-length and time of collection. These results indicate that Japanese common squid is a suitable bioindicator for monitoring OCs pollution in waters around Japan. With regard to the geographical distribution of OCs in this species collected from waters around Japan, OCs concentrations in specimens from Japan Sea were higher than those from the Pacific Ocean. This result might reflect some existing of local pollution sources of OCs around Japan Sea, and slower water exchange between Japan Sea and open ocean.