Contamination status and potential release of trace metals in a mangrove forest sediment in Ho Chi Minh City,Vietnam

Can Gio district is located in the coastal area of Ho Chi Minh City, southern Vietnam. Discharge of wastewater from Ho Chi Minh City and neighboring provinces to the rivers of Can Gio has led to concerns about the accumulation of trace metals (As, Cu, Cr, Ni, Pb, and Zn) in the coastal sediments. The main objective of this study was to assess the distribution of As, Cu, Cr, Ni, Pb, and Zn in surface and core sediments and to evaluate the contamination status in relation to local background values, as well as the potential release of these selected trace metals from sediments to the water environment. Sediment characteristization, including determination of fine fraction, pH, organic matter, and major elements (Al, Fe, Ca, K, Mg, and S), was carried out to investigate which parameters affect the trace metal enrichment. Fine fraction and Al contents were found to be the controlling proxies affecting the distribution of trace metals while other sediment characteristics did not show any clear influence on trace metals’ distribution. Although As concentrations in the sediments were much higher compared to its reference value in other areas, the enrichment factor based on local background values suggests minor contamination of this element as well as for Cr, Cu, and Pb. Risk assessment suggested a medium to very high risk of Mn, Zn, and Ni under acidification. Of importance is also that trace metals in sediments were not easily mobilized by organic complexation based on their low extractabilities by ammonium-EDTA extraction.

     

Power matters in closing the phenotyping gap

Much of our understanding of physiology and metabolism is derived from investigating mouse mutants and transgenic mice, and open-access platforms for standardized mouse phenotyping such as the German Mouse Clinic (GMC) are currently viewed as one powerful tool for identifying novel gene-function relationships. Phenotyping or phenotypic screening involves the comparison of wild-type control mice with their mutant or transgenic littermates. In our study, we explored the extent to which standardized phenotyping will succeed in detecting biologically relevant phenotypic differences in mice generated and provided by different collaborators. We analyzed quantitative metabolic data (body mass, energy intake, and energy metabolized) collected at the GMC under the current workflow, and used them for statistical power considerations. Our results demonstrate that there is substantial variability in these parameters among lines of wild-type C57BL/6 (B6) mice from different sources. Given this variable background noise in mice that serve as controls, subtle phenotypes in mutant or transgenic littermates may be overlooked. Furthermore, a phenotype observed in one cohort of a mutant line may not be reproducible (to the same extent) in mice coming from a different environment or supplier. In the light of these constraints, we encourage researchers to incorporate information on intrastrain variability into future study planning, or to perform advanced hierarchical analyses. Both will ultimately improve the detectability of novel phenotypes by phenotypic screening. Carola W. Meyer and Ralf Elvert contributed equally to this work.     

Weighing the pig never made it heavier: Auditing OHS,social auditing as verification of process in Australia

South Australian organizations assess their OHSMS through audits as evidence of risk control and to help make workplaces healthy and safe. Auditing is an evaluative process regarded as an important step in the cycle of continuous improvement in OHS. Auditing began with financial audits conducted for reasons of corporate governance: for accountability, to inform management decisions and to provide market confidence. Society expects audits to be a tool of regulation, governance and accountability, but celebrated failures of audits to warn of impending financial collapse in organizations in recent years appears to have led to an increased fervour for auditing, rather than a decline. Social audits, including auditing of OHSMS, are intended to determine that an organization is meeting its corporate social responsibilities; but what is audited is often contested and requires subjective analysis. Financial and social audits are subject to failure: unintentional errors, deliberate fraud, financial interests causing undue influence, and undue influence from personal relationships between the auditor and client. We identify five further categories of failure: lack of worker participation; paperwork for the sake of the audit; goal displacement of audit scoring; confusion of audit criteria; and lack of auditor independence and skill. There has been a shift in focus: the current demand and preparation for auditing distracts organizations from the primary goal of making the workplace healthy and safe. We argue that auditing OHSMS has become a ritual rather than a means of improving workplace health and safety and should at least be treated with caution.     

Field trial of a new aeration system for enhancing biodegradation in a biopile

The influence of a new aeration system on the biopile performance was investigated. The purpose was to increase biodegradation efficiency by optimising airflow through the pile. During a 1-month field trial, the performance of a new system using two perforated vertical pipes with wind-driven turbines was compared with that of a standard pile configuration with two horizontal perforated pipes. Both piles were composed of a similar mix of diesel-contaminated soils, woodchips, compost and NPK fertiliser. Hydrocarbons were recovered using solvent extraction, and determined both gravimetrically and by gas chromatography. Total heterotrophs, pH and moisture content were also assessed. Air pressure measurements were made to compare the efficiency of suction in the pipes. Results at the end of the experiment showed that there was no significant difference between the two piles in the total amount of hydrocarbon biodegradation. The normalised degradation rate was, however, considerably higher in the new system than in the standard one, suggesting that the vertical venting method may have improved the efficiency of the biological reactions in the pile. The pressure measurements showed a significant improvement in the suction produced by the new aeration system. However, many factors other than the airflow (oxygen supply) may influence and limit the biodegradation rates, including moisture content, age of contaminants and the climatic conditions. Additional experiments and modelling need to be carried out to explore further the new aeration method and to develop criteria and guidelines for engineering design of optimal aeration schemes in order to achieve maximum biodegradation in biopiles.     

Cyclone mitigation, resource allocation and post-disaster reconstruction in south India: lessons from two decades of research

This paper opens with a history of development and disaster-prevention strategies in a cyclone-prone area of the east coast of India and traces the evolution in the area of British and Indian governments' programmes and policy over a century. Research over the last 20 years has shown, however, that the programmes and policies have failed to balance economic growth with safety. Resources intended for the benefit of all have been diverted by alliances of powerful people to a small minority, and recent developments have reduced the physical protection of the area. The result is that increasing numbers of people are vulnerable to the effects of cyclones and floods. The findings suggest that the best way to reduce vulnerability is to improve the socio-economic standing of the most vulnerable and for this to happen these people must have an assured income based on assets that will enable them to acquire social and economic credit-worthiness within the local economy. This paper presents evidence that suggests that non-governmental organisation (NGO)-supported co-operatives are the best way to achieve this through self-help and self-employment schemes. It also suggests that NGOs should be encouraged to take up environmentally and ecologically beneficial activities involving the poorest groups in the communities, in this way combining sustained self-employment with environmental protection.     

Inventory of Ocean Monitoring in the Southern California Bight

Monitoring of the ocean environment in southern California, USA, has been conducted by a diverse array of public and private organizations with different motivations, working on a variety of spatial and temporal scales. To create a basis from which to integrate information from these diverse programs, we conducted an inventory of ocean monitoring activities in the Southern California Bight to address the following questions: (1) How much money is being expended annually on marine monitoring programs? (2) Which organizations are conducting the most monitoring? (3) How are resources allocated among the different types of monitoring programs? This inventory focused on programs existing, or those expected to be in existence, for at least 10 years and that were active at any time between 1994 and 1997. For each program identified for inclusion in this study, information was collected on the number of sites, sampling intensity, parameters measured, and methods used. Levels of effort were translated into cost estimates based upon a market survey of local consulting firms. One hundred fourteen marine monitoring programs, conducted by 65 organizations and costing US $31 million annually, were identified. Most of the effort (81 programs, 65% of samples, 70% of costs) was expended by ocean dischargers as part of their compliance with National Pollutant Discharge Elimination System (NPDES) permit requirements. Federal programs (11 programs, 25% of samples, 10% of total expenditures) expended more than state or local government programs. More than one quarter of monitoring expenditures were conducted to measure concentrations and mass of effluent inputs to the ocean. The largest effort expended on receiving water monitoring was for measuring bacteria, followed by sediments, fish/shellfish, water quality, and intertidal habitats. The large level of expenditures by individual agencies has presented opportunities for integrating small, site-specific ocean monitoring programs into regional- and national-scale monitoring and assessment programs.