Traceability,quality assurance,and standards

The development of traceability in low-level radioactivity measurements is discussed. The role that the development of large quantities of natural matrix standards can play is also discussed.     

Aerobiological,ecological, and health linkages

Aerobiology is an interdisciplinary science representing the presence and movement of biological particles in the earth's atmosphere. As an important component of air quality, the impact of these particles on human populations and agriculture were discussed in terms of the ecology of the landscape targets involved. The role of aerobiology in air quality studies was considered.     

Aquatic arsenic: Toxicity,speciation, transformations,and remediation

This paper reviews the current knowledge on the toxicity, speciation and biogeochemistry of arsenic in aquatic environmental systems. The toxicity of arsenic is highly dependent on the chemical speciation. The effects of pH, E_h, adsorbing surfaces, biological mediation, organic matter, and key inorganic substances such as sulfide and phosphate combine in a complex and interwoven dynamic fashion to produce unique assemblages of arsenic species. The number of different arsenic species found in environmental samples and an understanding of the transformations between arsenic species has increased over the past few decades as a result of new and refined analytical methods. Changes in arsenic speciation and in total arsenic content of foods upon processing have suggested possible risks associated with processed and unprocessed food. Arsenic removal from water using adsorbents, chemical oxidation, photolysis and photocatalytic oxidation techniques is also reviewed.     

Revision and meta-analysis of selected biosphere parameter values for chlorine, iodine, neptunium, radium, radon and uranium

There is a continual supply of new experimental data that are relevant to the assessment of the potential impacts of nuclear fuel waste disposal. In the biosphere, the traditional assessment models are data intensive, and values are needed for several thousand parameters. This is augmented further when measures of central tendency, statistical dispersion, correlations and truncations are required for each parameter to allow probabilistic risk assessment. Recent reviews proposed values for 10-15 key element-specific parameters relevant to (36)Cl, (129)I, (222)Rn, (226)Ra, (237)Np and (238)U, and some highlights from this data update are summarized here. Several parameters for Np are revised downward by more than 10-fold, as is the fish/water concentration ratio for U. Soil solid/liquid partition coefficients, Kd, are revised downward by 10-770-fold for Ra. Specific parameters are discussed in detail, including degassing of I from soil; sorption of Cl in soil; categorization of plant/soil concentration ratios for U, Ra and Np; Rn transfer from soil to indoor air; Rn degassing from surface water; and the Ca dependence of Ra transfers.     

Population,development,and environment in India

High population growth and continued economic development have caused serious environmental damage in the Asia Pacific region.However,the recent experience is that the pace of environmental degradation is faster in developing countries than in developed countries.To this end,the study seeks to assess the impact of population pressure on India’s environment,with particular reference to the degradation of natural endowments like land and water resources and the resultant environmental pollution in the six regions of India.The rapid economic growth and expansion of infrastructure development in recent decades have not come without serious environmental consequences particularly in the southern,northern,and western regions.But in the eastern,north-eastern,and central regions of the country,environmental damage has been mainly due to rapid population growth.     

Blood cadmium,mercury, and lead in children: An international comparison of cities in six European countries,and China,Ecuador, and Morocco

Children's blood-lead concentration (B-Pb) is well studied, but little is known about cadmium (B-Cd) and mercury (B-Hg), in particular for central Europe. Such information is necessary for risk assessment and management. Therefore, we here describe and compare B-Pb, B-Cd and B-Hg in children in six European, and three non-European cities, and identify determinants of these exposures. About 50 school children (7–14 years) from each city were recruited (totally 433) in 2007–2008. Interview and questionnaire data were obtained. A blood sample was analyzed: only two laboratories with strict quality control were used. The European cities showed only minor differences for B-Cd (geometric means 0.11–0.17 μg/L) and B-Pb (14–20 μg/L), but larger for B-Hg (0.12–0.94 μg/L). Corresponding means for the non-European countries were 0.21–0.26, 32–71, and 0.3–3.2 μg/L, respectively. For B-Cd in European samples, traffic intensity close to home was a statistically significant determinant, for B-Hg fish consumption and amalgam fillings, and for B-Pb sex (boys higher). This study shows that European city children's B-Cd and B-Pb vary only little between countries; B-Hg differs considerably, due to varying tooth restoration practices and fish intake. Traffic intensity seemed to be a determinant for B-Cd. The metal concentrations were low from a risk perspective but the chosen non-European cities showed higher concentrations than the cities in Europe.     

Risks, risk taking, and societal decisions

Risk assessment is an important tool to help evaluate the appropriate course for social decisions. But this methodology does not appear to have played a significant role in such decisions. Moreover, public decisions often appear to be at wide variance with what course risk assessment would counsel. In this paper risk is defined, the nature of risk taking is examined, and risk assessment issues in terms of societal decisions are identified. Eight such issues are listed as technical challenges for risk assessors to take into consideration if their analyses are to be more successful in influencing public policy. Finally, the paper suggests two operative guidelines to improve the effectiveness of risk assessment influence on social decisions. One is to recognize that risk assessment is only one input, albeit an important one, to such decisions. The other is to strive for simplicity without loss of completeness or exactness.     

Science, Research, Knowledge and Capacity Building

A small part of the scientific community is seeking hard to enhance the contribution of science, knowledge and capacity building to environmentally sustainable and socially fair human development around the world. Many researchers over the globe share the same commitment – anchored in concerns for the human condition. They believe that science and research can and have influenced sustainability. Therefore their main goals are to seek and build up knowledge, know-how and capacity that might help to feed, nurture, house, educate and employ the world's growing human population while conserving its basic life support systems and biodiversity. They undertake projects, that are essentially integrative, and they try to connect the natural, social and engineering sciences, environment and development of communities, multiple stakeholders, geographic and temporal scales. More generally, scientists engaged in sustainable development are bridging the worlds of knowledge and action. This pro-active, heavily ethics- and wisdom-based "science for sustainability" can be seen as the conclusion of all dialogues and discussions amongst scientists at the World Summit on Sustainable Development (WSSD) 2002 in Johannesburg. The "Plan of Implementation" after WSSD will be based on political will, practical steps and partnerships with time-bound actions. Several "means of implementation" are going to be proofed and initiated: finance, trade, transfer of environmentally sound technology, and, last but not least, science and capacity building.Some characteristics of working scientific sustainability initiatives are that they are regional, place-based and solution-oriented. They are focusing at intermediate scales where multiple stresses intersect, where complexity is manageable, where integration is possible, where innovation happens, and where significant transitions toward sustainability can start bottom-up. And they have a fundamental character, addressing the unity of the nature – society system, asking how that interactive system is evolving and how it can be consciously, if imperfectly, steered through the reflective mobilization and application of appropriate knowledge and know-how. The aims of such sustainability-building initiatives conducted by researchers are: first to make significant progress toward expanding and deepening the research agenda of science and knowledge-building for sustainability; secondly to strengthen the infrastructure and capacity for conducting and applying science, research and technology for sustainability – everywhere in the world where it is needed; and thirdly, to connect science, policy and decision-making more effectively in pursuit of a faster transition towards real sustainable development. The overall characteristic is, that sustainability initiatives are mainly open-ended networks and dialogues for the better future. A world society that tries to turn towards sustainable development has to work hard to refine their clumsy technologies, in "earthing" their responsibility to all creatures and resources, in establishing democratic systems in peace and by heeding human rights, in building up global solidarity through all mankind and in commit themselves to a better life for the next generations.     

Radioecology, radiobiology, and radiological protection: frameworks and fractures

A framework for the protection of the general public has been in existence for a very long time, although steps have recently been made by the ICRP to ensure that it is more fully comprehensive with regard to all actual and potential exposure situations. Protection of the environment, however, has only recently begun to be addressed in a structured manner, and is still an evolving subject. Nevertheless, it needs to be centred around some form of parallel framework to that which has evolved for the protection of human beings, although clearly on a different scale. It also needs to be embedded within the basic science of radiobiology, and form a central part of radioecology.     

Separation and measurement of thorium, plutonium, americium, uranium and strontium in environmental matrices

A technique for the isolation of thorium (Th), plutonium (Pu), americium (Am), uranium (U) and strontium (Sr) isotopes from various environmental matrices has been adapted from a previously published method specific to water samples (Maxwell, 2006). Separation and isolation of the various elemental fractions from a single sub-sample is possible, thereby eliminating the need for multiple analyses.The technique involves sample dissolution, concentration via calcium phosphate co-precipitation, rapid column extraction using TEVA™, TRU™ and Sr-Spec™ resin cartridges, alpha spectrometry for Th, Pu, U and Am and Cerenkov counting for Sr.Various standard reference materials were analysed and chemical yields are in the range of 70-80% for Th, Am, U and Sr and 50-60% for Pu. Sample sizes of up to 10 L for water, 5 g for dry soil and sediment and 10 g for dry vegetation and seaweed can be processed using this technique.     

Attributable risk, probability of causation, assigned shares, and uncertainty

Calculations of attributable risks, probabilities of causation, and assigned shares attracted increasing interest recently, particularly since the enactment of the Orphan Drug Act. Although efforts have been limited mostly to radiation as the toxic agent, the concept is general to all toxicants. In this paper, the systematic and random uncertainties in calculations of assigned shares are reviewed globally, and possibilities for their reduction are discussed. In addition, an algebraic study is made of the influence of random uncertainties in the input parameters on the random error of the assigned shares. Three dose-effect functions, appropriate for the low-dose, low-effects regions that are of interest here, are chosen for this investigation, and the algebraic properties of the random errors of the assigned shares are discussed. For shares near 0 and 1, the errors are shown to be small and to depend linearly on the value of the shares; the errors are largest for values of the shares near 50%, that is, in the region of almost equal or equal shares.     

Trace metal occurrence and distribution in sediments and mangroves,Pumicestone region,southeast Queensland,Australia

The Pumicestone region is a unique catchment in northern Moreton Bay, southeast Queensland. The region supports a wide range of land-use activities as well as attractions such as nature conservation areas. One environmental aspect that has not previously been addressed in this area is the occurrence of minor and trace metals in estuarine sediments associated with the main estuaries of the region. The trace metals included in this investigation are: vanadium, chromium, molybdenum, cobalt, nickel, copper, zinc, cadmium, lead and arsenic. To determine and evaluate the occurrence and distribution of metals in the area, several components have been analysed: bedrock material, pre-industrial settings, recent estuarine sediments, soils of estuarine origin and mangrove pneumatophores. The 40 sites chosen for sediment and soil samples cover a variety of estuarine settings and represent a range of natural conditions in terms of channel and bank morphology, tidal energy, vegetation cover, relationship to bedrock, water salinity and land disturbance. The chemical, mineralogical and statistical analyses employed in this study enabled (a) establishment of background values for the area, (b) determination of relationships between metals and (c) identification of sites with anomalous metal concentrations. All the metals found in the sediments of the area are sourced from the geological bedrock. The dominant trace elements identified in sediments are Zn, V and Cr. The remaining metals are highly variable spatially. All trace metals are controlled by the presence of Fe and Mn oxides, and by the grainsize of the sediment. Typically, fine-grained Fe-rich materials tend to adsorb more trace metals than sandy sediments. In soils that have developed from estuarine muds, some metals such as Cr, Mo, Pb and As tend to be in larger quantities than in the estuarine counterparts. Some of the elements, which occur in significant amounts in the sediment, have been detected in mangrove tissue (Avicenniamarina) such as V, Cr, Zn, Fe and Mn. Of particular note is Cu, which is present in mangrove tissue in quantities many times exceeding the sediment concentration. The comparative analysis of pre-industrial settings and recent sediments and soils highlighted some areas of metal enrichment such as acid-affected sites where oxidation of pyrite has mobilised metals from sediments; these metals are then redistributed in Fe-rich surficial layers. Disturbed banks within the estuaries are also likely to have low levels of metal enrichment due to boating activities.     

Chemical dusts, vapours, and fumes causing asthma

Allergic respiratory disease due to common allergens of organic origin is wwell known. Less familiar, but of increasing importance, are chemicals of organic and inorganic nature, met as dusts, vapours, and fumes. Their relevance is shown in occupational respiratory allergic disorders. Confirmation is given by “real life,” simulated, occupational-type provocation tests. Controlled exposure with minute amounts for brief periods, thus closely simulating allergic sensitivity, can precisely identify etiological causes in often complex exposures. The capacity of these widely different agents in different forms to elicit the different patterns of asthmatic reactions, is a pointed example of their potential role, as well as the role of chemical agents in general. The introduction into indoor environments of such materials demands consideration of their possible allergenic ffects and of the need to recognise the various forms of allergic respiratory reaction they may cause.     

Branching processes, Markov chains, and competing risks

This paper re-proves and generalizes results by Hardin and Sweet on the time to absorption in certain Markov chains by using a theorem on the time to extinction in multitype branching processes. Renaming “absorption” as “death” and “state immediately before absorption” as “cause of death” makes possible an interpretation in terms of competing risks. This is of very limited value, however, due to the rather severe mathematical restrictions on the Markov chains at hand.     

Parxit,the United States,and the world

<正>1.Introduction And now we have Parxit.On 1 June 2017,President Trump issued the highly unpopular announcement that the United States will withdraw from the 2015 Paris Agreement on Climate Change.In this brief piece,I will try to explain the reasons for this nearly unprecedented act of foreign policy folly(Ronald Reagan did pull out of the Law of the Sea     

劳动力转移、性别差异与农地流转及合约选择

通过构建“劳动力转移-性别差异-农地流转及合约选择”分析框架,分析劳动力转移性别差异背后的行为经济学含义,进而探讨不同性别的劳动力转移对农户农地流转供给决策与合约选择的差异化影响机制。理论研究表明,女性在家庭中起粘结家庭成员的作用,女性劳动力非农就业更能体现家庭的“离农”,因而女性劳动力的非农就业行为对农户农地流转供给决策具有更明显的促进作用;男性是农户家庭在村庄中排他能力的标志,具有不可忽视的农地流转风险规避功能,因而男性劳动力的外出就业距离对农户农地流转的合约选择起决定性作用。利用全国9省(区)4772个农户样本数据进行实证分析,计量结果表明:①女性劳动力非农就业比例每增加10%,农户转出农地面积占承包地面积比例增加1.06%;②男性劳动力县外就业比例每增加10%,农户转出农地时签订关系型合约的可能性增加1.11%;③男性劳动力县外就业比例每增加10%,意愿合约形式为无合同的可能性增加0.63%,意愿合约形式为口头合同的可能性增加0.29%,意愿合约形式为书面合同的可能性减少0.91%。这意味着,为了劳动力流转市场与农地流转市场更流畅地互动,应为农村女性劳动力营造一个更加合适、有利和公平的非农就业环境,这可成为未来农村劳动力就业扶持政策的重要方向。另一方面,促进正式契约与关系型合约的有机衔接,有利于农地流转合约的正式化与规范化,从而为农地流转市场的健康发育提供有力保障。     

Ozone and natural systems: understanding exposure,response, and risk

Research aimed at understanding the response of plants to ozone has been conducted for over four decades but little of it has addressed intact natural systems. Even so, there is sufficient scientific information at this time to support air quality standards that will protect natural terrestrial ecosystems from ozone. What is unknown is the risk associated with continued exposure of natural systems, including both above- and below-ground components, in combination with other stresses including changing temperature and precipitation, elevated carbon dioxide, pests and pathogens, invasive species, and other activities that may fragment the landscape. Research to support an assessment of the ecological risk associated with ozone as it exists, in a milieu of stresses, must include endpoints beyond those addressed in the past, primarily productivity and species composition. To estimate the risk to society of ozone impacts on natural systems, endpoints such as the integrity of soil food webs, the quantity and quality of water supplied from terrestrial ecosystems, wildlife and recreational values, and the transfer and fate of carbon, nutrients, and water within the systems must be quantified. Not only will this research provide the basis for a sound estimate of risk, but also it will improve our understanding of fundamental ecosystem processes.