Mercury speciation in highly contaminated soils from chlor-alkali plants using chemical extractions

A four-step novel sequential extraction procedure (SEP) was developed to assess Hg fractionation and mobility in three highly contaminated soils from chlor-alkali plants (CAPs). The SEP was validated using a certified reference material (CRM) and pure Hg compounds. Total, volatile, and methyl Hg concentrations were also determined using single extractions. Mercury was separated into four fractions defined as water-soluble (F1), exchangeable (F2) (0.5 M NH4Ac-EDTA and 1 M CaCl2 were tested), organic (F3) (successive extractions with 0.2 M NaOH and CH3COOH 4% [v/v]), and residual (F4) (HNO3 + H2SO4 + HClO4). The soil characterization revealed extremely contaminated (295 +/- 18 to 11 500 +/- 500 mg Hg kg(-1)) coarse-grained sandy soils having an alkaline pH (7.9-9.1), high chloride concentrations (5-35 mg kg(-1)), and very low organic carbon content (0.00-18.2 g kg(-1)). Methyl Hg concentrations were low (0.2-19.3 microg kg(-1)) in all soils. Sequential extractions indicated that the majority of the Hg was associated with the residual fraction (F4). In Soils 1 and 3, however, high percentages (88-98%) of the total Hg were present as volatile Hg. Therefore, in these two soils, a high proportion of volatile Hg was present in the residual fraction. The nonresidual fraction (F1 + F2 + F3) was most abundant in Soil 1 (14-42%), suggesting a higher availability of Hg in this soil. The developed and validated SEP was reproducible and efficient for highly contaminated samples. Recovery ranged between 93 and 98% for the CRM and 70 and 130% for the CAP-contaminated soils.     

Spatio-temporal Analysis of Acute Admissions for Ischemic Heart Disease in NSW,Australia

The recently funded Spatial Environmental Epidemiology in New South Wales (SEE NSW) project aims to use routinely collected data in NSW Australia to investigate risk factors for various chronic diseases. In this paper, we present a case study focused on the relationship between social disadvantage and ischemic heart disease to highlight some of the methodological challenges that are likely to arise.     

The bicultural life experience of career-oriented black women

This study explores the bicultural life experience of black career-oriented women. Seventy-one women participated in a larger study on the life experiences of black women. Of this sample, 21 (29 per cent) of the women were identified as being career-oriented. Findings reveal that the women perceive themselves as living in two distinct cultural contexts, one black the other one white. The women compartmentalize the various components of their lives in order to manage the bicultural dimensions. In addition, they tend to have highly complex life structures to embrace both cultural contexts.     

Factors to consider before production and commercialization of aquatic genetically modified organisms: the case of transgenic salmon

Many genetically modified plants have been developed, and four of them (soya, maize, cotton, and colza) representing more than 99% of commercial crops, are widely distributed, mainly in the United States and in America [ISAAA, 2006. Report on global status on biotech/GM crops, Brief 35. International Service for the Acquisition of Agri-biotech Applications organization, US]. Yet all over the world policy is still in development in regard to authorization of modified plants and modified and/or cloned animals for food or feed and for their environmental release. The most advanced animal commercial projects concern various fish species, more easy to genetically transform, notably because conception and development take place in water and easy access to numerous eggs. A request for authorization to introduce genetically modified (GM) salmon onto the market has been presented to the Food and Drug Administration (FDA) of the US. In the interim, questions have been raised concerning the impacts of transgenic salmon, modified for productivity, on aquaculture, wildlife, ecosystems and on human health. Herein we review these scientific studies and sanitary, environmental, social and economic arguments. This paper analyses current gaps in the knowledge of the impacts of transgenic fish and proposes legislation orientations necessary for environmental and sanitary protection, should the marketing of animal genetically modified organisms (GMOs) be authorized.     

Bird pollination of Canary Island endemic plants

The Canary Islands are home to a guild of endemic, threatened bird-pollinated plants. Previous work has suggested that these plants evolved floral traits as adaptations to pollination by flower specialist sunbirds, but subsequently, they appear to have co-opted generalist passerine birds as sub-optimal pollinators. To test this idea, we carried out a quantitative study of the pollination biology of three of the bird-pollinated plants, Canarina canariensis (Campanulaceae), Isoplexis canariensis (Veronicaceae) and Lotus berthelotii (Fabaceae), on the island of Tenerife. Using colour vision models, we predicted the detectability of flowers to bird and bee pollinators. We measured pollinator visitation rates, nectar standing crops as well as seed-set and pollen removal and deposition. These data showed that the plants are effectively pollinated by non-flower specialist passerine birds that only occasionally visit flowers. The large nectar standing crops and extended flower longevities (>10 days) of Canarina and Isoplexis suggests that they have evolved a bird pollination system that effectively exploits these low frequency non-specialist pollen vectors and is in no way sub-optimal. Seed set in two of the three species was high and was significantly reduced or zero in flowers where pollinator access was restricted. In L. berthelotii, however, no fruit set was observed, probably because the plants were self-incompatible horticultural clones of a single genet. We also show that, while all three species are easily detectable for birds, the orange Canarina and the red Lotus (but less so the yellow-orange Isoplexis) should be difficult to detect for insect pollinators without specialised red receptors, such as bumblebees. Contrary to expectations if we accept that the flowers are primarily adapted to sunbird pollination, the chiffchaff (Phylloscopus canariensis) was an effective pollinator of these species.     

Unruly pathogens: eliciting values for environmental risk in the context of heterogeneous expert knowledge

This paper examines some of the theoretical and methodological issues arising from the process of conceptualising and eliciting values for environmental risk in the context of heterogeneous expert knowledge. Drawing on the experience of a recent research project examining the relationship between livestock farming systems and microbial watercourse pollution the paper reflects critically upon efforts to develop an interdisciplinary assessment of the factors that may affect the loss of potential pathogens from agricultural land to water courses as the basis for targeting high risk fields and farms. The paper describes the procedures for designing the natural and cultural parameters that surround microbial risks and the issues that are raised for making whole system assessments workable based on contrasting and unstable systems of disciplinary insight. Situated within claims about the need for generating reliable and widely applicable assessments of environmental risk the paper suggests that interdisciplinary working raises important issues about the role of ‘uncertain’ knowledge in the management of ‘known’ risks.     

Sea ice cover and its influence on Adélie Penguin reproductive performance

The relationship between Adélie Penguins (Pygoscelis adeliae) and ice is well established, with sea ice influencing penguin populations through a variety of processes operating at different spatial and temporal scales. To further explain the relationship between sea ice and Adélie Penguin reproductive performance, we investigated the relative importance of various measures of sea ice cover on breeding success at Béchervaise Island, East Antarctica. Our results show a clear distinction in the response of penguins to different types of ice, as well as to the timing of the presence of sea ice. Nearshore sea ice, which is composed primarily of fast ice during the guard stage of the breeding season, had an overwhelmingly strong and negative impact on penguin reproductive performance. The influence of winter and offshore guard-stage ice was only evident in conjunction with nearshore ice. Predicting Adélie Penguin population growth in relation to changes in the sea ice environment may be complicated because penguin-ice interactions vary according to the type of sea ice present, the season in which it is present, and the processes contributing to population growth that are influenced by sea ice.     

Recognizing animal personhood in compassionate conservation

Compassionate conservation is based on the ethical position that actions taken to protect biodiversity should be guided by compassion for all sentient beings. Critics argue that there are 3 core reasons harming animals is acceptable in conservation programs: the primary purpose of conservation is biodiversity protection; conservation is already compassionate to animals; and conservation should prioritize compassion to humans. We used argument analysis to clarify the values and logics underlying the debate around compassionate conservation. We found that objections to compassionate conservation are expressions of human exceptionalism, the view that humans are of a categorically separate and higher moral status than all other species. In contrast, compassionate conservationists believe that conservation should expand its moral community by recognizing all sentient beings as persons. Personhood, in an ethical sense, implies the individual is owed respect and should not be treated merely as a means to other ends. On scientific and ethical grounds, there are good reasons to extend personhood to sentient animals, particularly in conservation. The moral exclusion or subordination of members of other species legitimates the ongoing manipulation and exploitation of the living worlds, the very reason conservation was needed in the first place. Embracing compassion can help dismantle human exceptionalism, recognize nonhuman personhood, and navigate a more expansive moral space.