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.     

Threshold and dose response estimation using the “filter model”

The “filter model” has been developed to explain the biologic effects of radiation and chemicals. We have examined nearly 300 sets of dose response data, of which 50 are presented here. Responses (induced by radiation and chemicals) which have been examined include in vitro survival studies on animal and plant tissues, induction of cellular aberrations and time to tumor or death. Similar data from in vivo studies has also been examined. All of the data appear to fit the model R = a lnD + b(lnD)² + c, where R is the response, a and b are parameters fitted by regression to a particular set of data, and c is the response at zero (or lowest) dose. By writing this model in exponential form, it can be seen that the response R results from multistage filtering (by net amounts a and b) of the initial dose, D. The threshold is obtained from this model as the point, $\text{D}\text{?}{}_{\mathrm{T}}$, at which the second derivative becomes zero. This is given by $\text{D}\text{?}{}_{\mathrm{T}}\text{=}\text{exp}\text{(1 ?}\text{a}\text{2b}\text{)}$ when a and b are oppositelt signed.     

An examination of health data following two major earthquakes in Russia

Thus the hazards to health observed from these two earthquakes can be summarised as follows: (a) massive immediate damage, the main victims being women and children; (b) the seriously injured suffer mainly from fractures (17%), head injuries (15-30%) and soft tissue conusions with haemhorrage; (c) a change in the physical features of a country which unfavourably affect the environment; (d) some time after the earthquake the appearance of communicable disease; (e) increases in cases of cardiovascular disease neuroses and psychoses.     

International competitive displacement from environmental control The quantitative gains from methodological refinement

This paper demonstrates empirically the gain from adopting more general equilibrium approaches in projecting the effects on domestic output and international trade of environmental controls. The suggested models include a partial equilibrium case where all industries are treated independently, an intermediate case incorporating effects in supplying industries, and general equilibrium formulations based on alternative macroeconomic conditions. U. S. data is used to evaluate these models. Under both pollutor pays and subsidy financing schemes, moving from the simplest case to the intermediate model results in quite different industry projections. Including macroeconomic factors appears particularly important in the classical setting.     

FRONTIER AREAS, RESOURCES, AND DEVELOPING NATIONS: THE CASE OF GUATEMALA

The conscientious and planned integration of frontier areas into the national economy can at least partially alleviate both environmental and economic problems that are common to many developing countries. Full development of the agricultural potential of frontier areas can lessen the environmental deterioration often found in traditionally settled regions. Exploitation of mineral resources, in particular energy resources, can lessen economic burdens associated with increased costs of imported energy. The authors examine how recent international developments have spurred the government of Guatemala to undertake measures designed to develop a previously underutilized region. The short term negative consequences of increased costs for imported grains and petroleum may well have a positive result in the long term insofar as they lead to more balanced and rational use of land and resources.