What Exactly Is an Endangered Species? An Analysis of the U.S. Endangered Species List: 1985–1991

Critics of the Endangered Species Act have asserted that is protects an inordinate number of subspecies and populations, in addition to full species, and that the scientific rationale for listing decisions is absent or weak. We reviewed all U.S. plants and animals proposed for listing or added to the endangered species list from 1985 through 1991 to determine the relative proportion of species, subspecies, and populations, and their rarity at time of listing. Approximately 80% of the taxa added to the list were full species, 18% were subspecies, and 2% were distinct populations segments of more widespread vertebrate species. The proportion of subspecies and populations was considerably higher among birds and mammals than among other groups. The median populations size at time of listing for vertebrate animals was 1075 individuals; for invertebrate animals it was 999. The median population size of a plant at time of listing was less than 120 individuals. Earlier listing of declining species could significantly improve the likelihood of successful recovery, and it would provide land managers and private citizens with more options for protecting vanishing plants and animals at less social or economic cost.     

Can health feasibly be considered as part of the planning process in Scotland?

The planning system is significant because of its capacity to determine the quality of the built environment as well as the health, well-being and quality of life of the individuals and communities therein. Development planning is especially important because of the long-term impact of the decisions. This paper was developed in response to increasing recognition amongst HIA practitioners in Scotland of the importance of planning for health. It focuses on the relationship between the planning system in Scotland, specifically the Development Planning element of it, and population health and considers how the health impact assessment (HIA) approach can facilitate and support joint working with planners. In particular, consideration is given to the potential impact of the introduction of Strategic Environmental Assessment (SEA) on the linkages between health, HIA and planning.     

Chromium speciation and fractionation in ground and surface waters in the vicinity of chromite ore processing residue disposal sites

Chromium concentrations of up to 91 mg l(-1) were found by ICP-OES for ground water from nine boreholes at four landfill sites in an area of S.E. Glasgow/S. Lanarkshire where high-lime chromite ore processing residue (COPR) from a local chemical works had been deposited from 1830 to 1968. Surface water concentrations of up to 6.7 mg l(-1) in a local tributary stream fell to 0.11 mg l(-1) in the River Clyde. Two independent techniques of complexation/colorimetry and speciated isotope dilution mass spectrometry (SIDMS) showed that Cr was predominantly (>90%) in hexavalent form (CrVI) as CrO4(2-), as anticipated at the high pH (7.5-12.5) of the sites. Some differences between the implied and directly determined concentrations of dissolved CrIII, however, appeared related to the total organic carbon (TOC) content. This was most significant for the ground water from one borehole that had the highest TOC concentration of 300 mg l(-1) and at which < 3% of Cr was in the form of CrVI. Subsequent ultrafiltration produced significant decreases in Cr concentration with decreasing size fractions, e.g. <0.45 microm, < 100 kDa, <30 kDa and < 1 kDa by the tangential-flow method. As this appeared related more to concentrations of humic substances than of TOC per se, horizontal bed gel electrophoresis of freeze-dried ultrafilter retentates was carried out to further characterise the CrIII-organic complex. This showed for the main Cr-containing fraction, 100 kDa-0.45 microm, that the Cr was associated with a dark brown band characteristic of organic (humic) matter. Comparison of gel electrophoresis and FTIR results for ultrafilter retentates of ground water from this borehole with those for a borehole at another site where CrVI predominated suggested the influence of carboxylate groups, both in reducing CrVI and in forming soluble CrIII-humic complexes. The implications of this for remediation strategies (especially those based on the addition of organic matter) designed to reduce highly mobile and carcinogenic Cr(VI)O4(2-) to the much less harmful CrIII as insoluble Cr(OH)3 are discussed.     

Patients' attitudes following chorionic villus sampling

The attitudes of 190 patients who had undergone chorionic villus sampling (CVS) were assessed by means of a questionnaire. One hundred and fifty-two patients replied of whom 68 (45 per cent) were referred because of increased maternal age and in the other 84 cases the indications included previous chromosomal abnormalities, fetal sexing, DNA analysis, and biochemical analysis. One hundred and twenty-two patients had a transcervical procedure, 24 had a transabdominal, and six patients required both procedures. One hundred and forty-one patients (93 per cent) reported CVS to be a satisfactory procedure, and the same percentage thought earlier diagnosis was beneficial. Thirty-nine patients (81 per cent) reported a better experience with CVS than with a previous amniocentesis. A majority of patients (93 per cent) wished a CVS in a future pregnancy and 137 patients (97 per cent) would accept a risk of miscarriage from the procedure of twice that quoted for amniocentesis (1 per cent).     

Prenatal diagnosis using deletion studies in Duchenne muscular dystrophy

Accurate carrier testing and prenatal diagnosis in Duchenne muscular dystrophy (DMD) families is facilitated when an Xp21 deletion is found to be segregating within a family. We discuss the results of the DNA testing in two families, one in which DNA from affected males was available for study and the other in which no DNA from an affected male was available. Factors complicating the counselling of DMD deletion families are outlined.     

Modulation of steroidogenesis by coastal waters and sewage effluents of Hong Kong, China, using the H295R assay

BACKGROUND, AIM, AND SCOPE: The presence of a variety of pollutants in the aquatic environment that can potentially interfere with the production of sex steroid hormones in wildlife and humans has been of increasing concern. The aim of the present study was to investigate the effects of extracts from Hong Kong marine waters, and influents and effluents from wastewater treatment plants on steroidogenesis using the H295R cell bioassay. After exposing H295R cells to extracts of water, the expression of four steroidogenic genes and the production of three steroid hormones were measured. MATERIALS AND METHODS: Water samples were collected during the summer of 2005 from 24 coastal marine areas and from the influents and effluents of two major waste water treatment plants (WWTPs) in Hong Kong, China. Samples were extracted by solid phase extraction (SPE). H295R cells were exposed for 48 h to dilutions of these extracts. Modulations of the expression of the steroidogenic genes CYP19, CYP17, 3betaHSD2, and CYP11beta2 were determined by measuring mRNA concentrations by real-time polymerase chain reaction (Q-RT-PCR). Production of the hormones progesterone (P), estradiol (E2), and testosterone (T) was quantified using enzyme linked immunosorbent assays (ELISA). RESULTS: Extracts from samples collected in two fish culture areas inhibited growth and proliferation of H295R cells at concentrations greater or equal to 10(5) L equivalents. The cells were exposed to the equivalent concentration of active substances in 10,000 L of water. Thus, to observe the same level of effect as observed in vitro on aquatic organisms would require a bioaccumulation factor of this same magnitude. None of the other 22 marine samples affected growth of the cells at any dilution tested. Twelve of the marine water samples completely inhibited the expression of CYP19 without affecting E2 production; inhibition of CYP17 expression was observed only in one of the samples while expression of CYP11beta2 was induced as much as five- and ninefold after exposure of cells to extracts from two locations. The expression of the progesterone gene 3betaHSD2 was not affected by any of the samples; only one sample induced approximately fourfold the production of E2. Although more than twofold inductions were observed for P and T production, none of these values were statistically significant to conclude effects on the production of these two hormones. While influents from WWTPs did not affect gene expression, an approximately 30% inhibition in the production of E2 and a 40% increase in P occurred for the exposure with influents from the Sha Tin and Stonecutters WWTPs, respectively. Effluents from WWTPs did not affect the production of any of the studied hormones, but a decrement in the expression of the aldosterone gene CYP11beta2 was observed for the Sha Tin WWTP exposure. No direct correlation could be established between gene expression and hormone production. DISCUSSION: Observed cytotoxicity in the two samples from fish culture areas suggest the presence of toxic compounds; chemical analysis is required for their full identification. Although effluents from WWTPs did not affect hormone production, other types of endocrine activity such as receptor-mediated effects cannot be ruled out. Interactions due to the complexity of the samples and alternative steroidogenic pathways might explain the lack of correlation between gene expression and hormone production results. CONCLUSIONS: Changes observed in gene expression and hormone production suggest the presence in Hong Kong coastal waters of pollutants with endocrine disruption potential and others of significant toxic effects. The aromatase and aldosterone genes seem to be the most affected by the exposures, while E2 and P are the hormones with more significant changes observed. Results also suggest effectiveness in the removing of compounds with endocrine activity by the WWTPs studied, as effluent samples did not significantly affect hormone production. The H295R cell showed to be a valuable toll in the battery required for the analysis of endocrine disrupting activities of complex environmental samples. RECOMMENDATIONS AND PERSPECTIVES: Due to the intrinsic complexity of environmental samples, a combination of analytical tools is required to realistically assess environmental conditions, especially in aquatic systems. In the evaluation of endocrine disrupting activities, the H295R cell bioassay should be used in combination with other genomic, biological, chemical, and hydrological tests to establish viable modes for endocrine disruption and identify compounds responsible for the observed effects.     

Bioavailability and mass balance studies of a commercial pentabromodiphenyl ether mixture in male Sprague-Dawley rats

Cyanogenic glycosides are common plant toxins. Toxic hydrogen cyanide originating from cyanogenic glycosides may affect soil processes and water quality. In this study, hydrolysis, degradation and sorption of dhurrin (4-hydroxymandelonitrile-beta-d-glucoside) produced by sorghum has been studied in order to assess its fate in soil. The log K(ow) of dhurrin was -1.18+/-0.08 (22 degrees C). Hydrolysis was a first-order reaction with respect to dhurrin and hydroxyl ion concentrations. Half lives ranged from 1.2h (pH 8.6; 25 degrees C) to 530d (pH 4; 25 degrees C). The activation energy of hydrolysis was 112+9kJ. At pH 5.8 and room temperature, addition of humic acids (50gl(-1)) increased the rate of hydrolysis tenfold, while addition of kaolinite or goethite (100-250gl(-1)) both decreased the rate considerably. No significant sorption to soil components could be observed. The degradation rates of dhurrin in top and subsoils of Oxisols, Ultisols, Alfisols and Mollisols were studied at 22 degrees C (25mgl(-1), soil:liquid 1:1 (w:V), pH 3.8-8.1). Half-lives were 0.25-2h for topsoils, and 5-288h in subsoils. Hydrolysis in solution explained up to 45% of the degradation in subsoils whereas the contribution in topsoils was less than 14%, indicating the importance of enzymatic degradation processes. The highest risk of dhurrin leaching will take place when the soil is a low activity acid shallow soil with low content of clay minerals, iron oxides and humic acids.