Interlocking Biological and Political Uncertainties in Public Decision Making : A Case Study at Mellery (Belgium)

Conference (1998, October 13)

A central question in health hazard associated with environmental pollution is the evaluation of level of exposure to a mixture of carcinogens and the estimation of the global health impact on the ... [more ▼]

A central question in health hazard associated with environmental pollution is the evaluation of level of exposure to a mixture of carcinogens and the estimation of the global health impact on the residents. The point is important to found a public health decision for site intervention or residents relocalisation. Belgium had to face such a problem at Mellery, a village which became internationally famous some years ago, when local residents denonced a local pollution originating from an industrial waste depository facility situated only 500 m from the centre of their village, in a former sand quarry. A central piece of the actions of the authorities was the original campaign organised to measure directly the level of exposure to carcinogens of a large group of voluntary local residents, children included, by measuring biomarkers of exposure in blood lymphocytes : for its high sensitivity, the frequency of sister chromatid exchanges (SCES) had been chosen. This biomonitoring method, quite commonly used to monitor occupational environment, had never before been applied to evaluate the potential health impact of the environment on a general population. Such data, although sophisticate and integrative, are only indicators of exposure and cannot be used, so far, as individual quantitative predictors of the possible evolution of the health of the individual persons. First designed as an epidemiological study, the campaign at Mellery revealed so high exposure levels that the experts did not keep with the original experimental line and decided to release individual information to the concerned persons, without much preparation nor risk communication policy. Several groups (experts, local doctors, local and regional authorities, public agencies and residents associations) were active integrating the information in their respective discourses, giving them specific interpretative and competing meanings. Any scenario for intervention had to be embedded in some meaningful and legitimating discourse : a quite difficult task for the authorities. The evolution of the expertise system used for public decision-making were marked by several such uncertainties (geological, biological, medical) but also by the difficult integration of health related aspects within environment interventions in the regulatory structures in Belgium : health responsibilities are scattered between federal and "communautaire" bodies, while most of the environmental actions are funded at the regional level. In this first heavy case, the young regional institutions reacted in a disorganized manner: they choose to not put at risk their frail power equilibrium and to not reconsider the attribution of the responsibilities. The authors propose to analyse how peculiar interlocking of the biological and political uncertainties were at the core of the general failure in public risk management around this landfill site: Mellery, after 10 years and a huge budget for site treatment, is still a nightmare for environmental authorities in Southern Belgium. [less ▲]

Construction d'une table de production pour le Douglas (Pseudotsuga menziesii (Mirb.) Franco) en Belgique

in Bulletin des Recherches Agronomiques de Gembloux (1992), 27(3), 327-347

A yield table was compiled for even-aged pure stands of Douglas fir (Pseudotsuga menziesii (MIRBK) FRANCO) in Belgium. It reflects the probable development of normal fully stocked stands under the ... [more ▼]

A yield table was compiled for even-aged pure stands of Douglas fir (Pseudotsuga menziesii (MIRBK) FRANCO) in Belgium. It reflects the probable development of normal fully stocked stands under the silviculture at the time of the data collection. The data were collected from 256 temporary sample plots, 87 of which were remeasured 2 or 3 times. A family of functions (the JOHNSON-SCHUMACHER model) was used to develop a site classification system based on the top height at age 50). The standing crop characteristics (number of trees, volume, basal area, mean stem basal area), calculated as a function of age and site index, are derived from stem girth distribution fitted by means of the WEIBULL function. Concerning the increments and the thinnings, the corresponding values were calculated from individual tree girth increments (from borings) and from comparison between stem distributions at the beginning and at the end of a period corresponding to a thinning cycle. The table is the basis on which a set of variable density yield tables will be prepared. The yield of Douglas fir trees in Belgium is also compared with the yield observed in neighbouring European countries. [less ▲]

High temperature crossover in paraconductivity of granular Y1Ba2Cu3O7-y

in Zeitschrift für Physik. B, Condensed Matter (1991), 84(1), 13-16

We have examined the deviation from linearity of the temperature dependence of the electrical resistivity of a YBaCuO ceramics. We have observed at high temperature a crossover behavior toward a ... [more ▼]

We have examined the deviation from linearity of the temperature dependence of the electrical resistivity of a YBaCuO ceramics. We have observed at high temperature a crossover behavior toward a logarithmic temperature dependence at lower temperature. It seems relevant to attribute the origin of such a term to a pair breaking mechanism contribution, thus to give a lower bound to the existence of superconductivity fluctuations onset temperature. Our findings also implies that carriers are bosons above T(c). [less ▲]

Probing conductivity fluctuations in high critical temperature superconductors

in Solid State Communications (1990), 73(2), 137-141

We comment and discuss published data on the electrical resistivity of high temperature superconductors in order to extract the dimensionality of superconductivity "critical" fluctuations. We present ... [more ▼]

We comment and discuss published data on the electrical resistivity of high temperature superconductors in order to extract the dimensionality of superconductivity "critical" fluctuations. We present arguments which indicate that observation of three temperature regimes is indeed possible: a scaling regime close to Tc and two regimes in the mean field region. In each regime, dominant scattering mechanisms can be different. [less ▲]

Superconductivity fluctuations in electrical and thermoelectrical properties of granular ceramic superconductors: Homogeneous versus fractal behavior

in Physical Review B (1990), 42(13), 8611-8614

Both the electrical-resistivity and the thermoelectric-power temperature-derivative diver- gences are examined in typical granular ceramic superconductors (YBa2Cu3O7-y and Bi1.75Pb0.25Ca2Sr2Cu3O10-z ... [more ▼]

Both the electrical-resistivity and the thermoelectric-power temperature-derivative diver- gences are examined in typical granular ceramic superconductors (YBa2Cu3O7-y and Bi1.75Pb0.25Ca2Sr2Cu3O10-z). Critical exponents are extracted in the region above the critical temperature. The dimensionality of anomalous superconductivity fluctuations is deduced. The same universal behavior is found for the excess resistivity and the excess thermoelectric power in a given system. It is shown that a homogeneous regime and a self-similar (fractal) behavior can be distinguished depending on the samples. The results are discussed in terms of superconductivity paths occurring through surface connections and of different values of the superconductivity S and percolation P coherence-length ratio. [less ▲]