Re-framing risk: the changing context of disaster mitigation and preparedness

This issue of Disasters explores the roles of NGOs and other actors in disaster mitigation and preparedness and also reviews broad international trends in risk management and disaster prevention. The need to address risk, and with that the motivation to improve disaster mitigation and preparedness, has tended to fall between the cracks of grander frameworks of development co-operation and humanitarian assistance. Despite the seemingly glaring need to reduce the horrific impact of floods, droughts and wars, disaster mitigation and preparedness have neither the allure of directly 'saving lives', nor of providing an 'escape from poverty'. There are, however, signs that risk management is becoming a mainstream concern. Factors such as the need to address factors that do not fit into traditional slots on the relief-development continuum, the rising economic costs of disasters and a growing acknowledgement that aid will never cover more than a small fraction of the costs of disasters are all leading to new approaches, priorities and institutional configurations. A realisation that dealing with risk and insecurity is a central part of how poor people develop their livelihood strategies has begun to position disaster mitigation and preparedness within many poverty alleviation agendas. A number of long-standing challenges remain; most of all, the complexities of maintaining the political will that is needed to ensure that risk management becomes more than a passing fad.     

Chloride persistence in a deiced access road drainage system

Three years of field data, classical linear reservoir theory, and a new dissolution model confirm the hypothesis that residual chloride from highway deicing applications dissolves into precipitation throughout the year. The measured input includes 52 storm hyetographs and logs of salt and premix applications on an access road with a closed drainage system subject to runoff, interflow, and baseflow. The output data feature discharge and conductivity in an outlet weir measured continuously from February 1998 to May 2000. Individual storm hydrographs and pollutographs yield calibrated first flush dissolved chloride concentrations and residual solid chloride loads that persist at appreciable levels over the entire period of record. The storm calibrations imply a source strength w of 2.01 x 10(-6) s(-1) that accurately models chloride dissolution kinetics through three salt seasons on the access road. This w rests on physically plausible values for the depression storage depth zeta (3 mm) and porosity n (0.40) that store the residual chloride.     

Industrial pollution and social deprivation: Evidence and complexity in evaluating and responding to environmental inequality

The local impacts of industrial pollution can take many forms and—whilst uncertain in their scale, severity and distribution—are widely recognised. The question of who in society potentially experiences these impacts through living near to emission sources has been little explored, at least in the UK. This paper reports on a study carried out for the Environment Agency, which examined the distribution of sites coming within the Industrial Pollution Control (IPC) regime against patterns of deprivation. Our analysis provides evidence of a socially unequal distribution of IPC sites in England, with sites disproportionately located and clustered together in deprived areas and near to deprived populations. In discussing these results we emphasise the methodological limitations of this form of environmental justice analysis and the crucial differences between proximity, risk and impact. We also consider the distinction between inequality and injustice and the difficult policy questions which arise when evaluating evidence of environmental inequality, including potential grounds for policy intervention.     

Fire and grazing effects on wind erosion, soil water content, and soil temperature

Selective grazing of burned patches can be intense if animal distribution is not controlled and may compound the independent effects of fire and grazing on soil characteristics. Our objectives were to quantify the effects of patch burning and grazing on wind erosion, soil water content, and soil temperature in sand sagebrush (Artemisia filifolia Torr.) mixed prairie. We selected 24, 4-ha plots near Woodward, OK. Four plots were burned during autumn (mid-November) and four during spring (mid-April), and four served as nonburned controls for each of two years. Cattle were given unrestricted access (April-September) to burned patches (<2% of pastures) and utilization was about 78%. Wind erosion, soil water content, and soil temperature were measured monthly. Wind erosion varied by burn, year, and sampling height. Wind erosion was about 2 to 48 times greater on autumn-burned plots than nonburned plots during the dormant period (December-April). Growing-season (April-August) erosion was greatest during spring. Erosion of spring-burned sites was double that of nonburned sites both years. Growing-season erosion from autumn-burned sites was similar to nonburned sites except for one year with a dry April-May. Soil water content was unaffected by patch burn treatments. Soils of burned plots were 1 to 3 degrees C warmer than those of nonburned plots, based on mid-day measurements. Lower water holding and deep percolation capacity of sandy soils probably moderated effects on soil water content and soil temperature. Despite poor growing conditions following fire and heavy selective grazing of burned patches, no blowouts or drifts were observed.     

Cesium-134 and strontium-85 in strawberry plants following wet aerial deposition

The understanding of the processes that control the behavior of radionuclides in crops can support policymakers to take actions to protect the environment and safeguard human health. Data concerning the behavior of radionuclides in fruits are limited. Strawberry (Fragaria x ananassa Duchesne) plants were contaminated on the aboveground part by sprinkling an aqueous solution of 134Cs and 85Sr at three growing stages: predormancy, anthesis, and beginning of ripening. Intercepted activity was more affected by the posture and physical orientation of leaves rather than by leaf area or biomass. Fruit interception ranges from 0.2 to 1.2% of the sprinkled activity. Translocation coefficients from leaf to fruit are on the order of 10(-4) for 134Cs and 10(-5) for 85Sr. Translocation reaches its highest intensity between anthesis and ripening. If deposition occurs when plants are bearing fruits, the fruit activity will be affected by the activity initially deposited on the fruit surfaces. This is important for 85Sr as it is not translocated in the phloem. The loss of the dead leaves at the resumption of growth causes high plant decontamination, but a fraction of both radionuclides remains in the storage organs, roots, and shoots, which is retranslocated to fruits in the following spring. The values of the environmental half-time, t(w), after deposition at predormancy are 114 d for 134Cs and 109 d for 85Sr. Cesium-134 tends to be allocated to fruits, while 85Sr remains in leaves and crowns. Translocation of radionuclides to roots results in soil contamination.     

Molecular prenatal diagnosis of 3-hydroxy−3-methylglutaryl coa lyase deficiency

We report the first molecular prenatal diagnosis of 3-hydroxy-3-methylglutaryl CoA lyase (HL) deficiency. The proband had a classic but severe presentation with hypoketotic hypoglycaemia and acidosis, secondary mental retardation, and epilepsy, and HL deficiency was documented in cultured fibroblasts. We found him to be homozygous for the frameshift mutation N46fs (+1), which yields a distinct pattern on single-strand conformation polymorphism (SSCP) analysis. In two subsequent pregnancies, molecular prenatal diagnosis was performed using SSCP. In the first, chorionic villus biopsy was normal. In the second pregnancy, amniocentesis revealed an affected fetus. In both pregnancies, the diagnosis was confirmed enzymatically. HL activity was less than 7 per cent of control values in amniocytes and fetal liver of the affected pregnancy. In the second pregnancy, amniotic fluid metabolite measurements by stable isotope dilution-selected ion monitoring mass spectrometry showed greater than 100-fold increases of 3-hydroxy-3-methylglutaric acid and of 3-methylglutaconic acid levels compared with controls.     

First-trimester aneuploidy screening using serum human chorionic gonadotropin (hCG), free ahCG,and progesterone

Immunochemical serum assays for human chorionic gonadotropin (hCG), the free ohCG subunit, and progesterone (P) were considered separately and in combination for their ability to screen for chromosomally abnormal pregnancies in the first trimester. Maternal serum was collected from 141 women undergoing chorionic villus sampling at 9–12 menstrual weeks. Trisomy 21 pregnancies had significantly higher hCG levels, while trisomy 18 and 13 pregnancies had markedly lower hCG and progesterone levels than those of chromosomally normal pregnancies. However, the discrimination of normal from aneuploid pregnancies was poor with either hCG alone, progesterone alone, or free ahCG alone. Much improved discrimination was obtained by combining hCG, free ahCG, and P into an aneuploidy index [(P/hCG)(free ahCG/hCG)]. This index distinguished 9 out of 17 (53 per cent) of the trisomy 21 pregnancies, while only misidentifying 5 out of 112 (4.5 per cent) of the normal pregnancies. The aneuploidy index thus appears promising as a first-trimester biochemical screen for aneuploid pregnancies.     

Human chorionic gonadotropin levels in pregnancies with aneuploid fetuses

Maternal serum human chorionic gonadotropin (hCG) and the free alpha-hCG subunit were evaluated in 249 women from 9 to 11 weeks gestation who subsequently underwent chorionic villus sampling for determination of fetal karyotype and in 20 women of 18 or more weeks gestation who were ascertained to have an aneuploid fetus by genetic amniocentesis. Seven of the first-trimester pregnancies were determined to be aneuploid and six had hCG levels in the normal range (one triploid pregnancy had elevated hCG levels) whereas 12 of the 20 secondtrimester cases had abnormal hCG levels and an additional three had elevated levels of alpha-hCG. This study confirms the previous report of abnormal maternal serum hCG levels in women with an aneuploid fetus at ≥ 18 weeks gestation and demonstrates that hCG evaluation is not useful at 9–11 weeks gestation for selecting pregnancies at risk for fetal aneuploidy.     

Prenatal diagnosis of smith–lemli–opitz syndrome is possible by measurement of 7-dehydrocholesterol in amniotic fluid

Amniocentesis was performed at 17.3 weeks in a pregnancy with severe intrauterine growth retardation. Cytogenetic studies on amniocytes were normal, 46,XX, and the pregnancy was continued. The diagnosis of Smith–Lemli–Opitz syndrome was suspected in the neonatal period and confirmed by the presence of 7-dehydrocholesterol (7-DHC) in the plasma (0.4 mmol/l, normal = not detectable) associated with a low total cholesterol concentration (0.4 mmol/l, normal = 2.56 ± 0.23). Retrospective analysis of the amniotic fluid sample revealed an elevated level of 7-DHC (0.022 mmol/l; normal = undetectable). Therefore measurement of 7-DHC levels in amniotic fluid during the second trimester of pregnancy is useful for the prenatal diagnosis of Smith–Lemli–Opitz syndrome in families at risk and should be considered in cases of severe growth retardation of unknown aetiology for which amniotic fluid is available and in which a normal chromosomal pattern in amniocytes is present.