Methodologies for determination of antimony in terrestrial environmental samples

Methodologies for the environmental analysis of total antimony and aqueous chemical speciation are critically reviewed, including preparation techniques for aqueous and solid matrices and the determination of solid state partitioning and recommendations are given for future research directions. Concentrations of total antimony commonly present in aqueous and solid environmental samples are readily determined using present day analytical techniques. This has resulted primarily from technological advances in microwave digestion for solid matrices and the development of plasma based analyte detection systems. ICP-AES and ICP-MS techniques are both utilised for the environmental analysis of total antimony concentrations. However, ICP-MS is increasingly favoured as a result of reduced spectral interferences and the potential for analyte detection in the pg mL(-1) range. Determination of aqueous antimony speciation presents a number of complex analytical challenges and highly selective separation and identification techniques are required prior to detection. The majority of published techniques including common applications of hydride generation are insufficiently selective for the determination of intrinsic chemical speciation and often only oxidation state data are obtained. The recent in-line applications of HPLC-ICP-MS offer the potential for highly selective separations of aqueous antimony species and determination of detailed chemical speciation data. However, considerable development work is required to optimise chromatographic separations and identify uncharacterised species resident in environmental systems. Analytical techniques to aid the determination of antimony's associations with solid environmental matrices include the application of chemical extraction procedures and leaching experiments. To date, this area of analytical research has received little attention and further studies are required to elucidate this aspect of antimony's environmental chemistry.     

Use of significance thresholds to integrate cumulative effects into project-level socio-economic impact assessment in Canada

A longstanding critique of project-level environmental assessment is that it is weak at addressing cumulative effects, and because of this many argue that cumulative effects are best managed at a regional scale. However, in the absence of regional management it is important that project-level assessment supports cumulative effects management as best as possible. In this paper we present case study socio-economic impact assessments of liquefied natural gas development on Aboriginal groups on Canada's west coast. The case studies use an analytical structure modified from typical Canadian practice including unambiguous and non-arbitrary significance thresholds grounded in stakeholder values to focus baselines, impact assessment, and significance determination on cumulative effects. This approach is found to be more capable of informing decision-makers on cumulative effects as well as more rigorous and transparent than typical assessments. Much of this approach is not conceptually new, but at least in western Canada such an approach is not typically used or meaningfully implemented by practitioners. As such, the case studies serve to illustrate how practice can bolster project-level assessment.     

Establishing the Canadian Community Monitoring Network

Community-based ecosystem monitoring activities in Canada are increasing in response to a number of factors including: (i) the needs of decision-makers for timely information on local environmental changes; (ii) limited use of government monitoring data and information by decision makers; (iii) government cuts to monitoring programs; (iv) the increasingly recognized need to include stakeholders in planning and management processes; and (v) the desire of citizens to contribute to environmental protection. To date there has been no network coordination of community based monitoring in Canada. This paper reports on the establishment of the Canadian Community Monitoring Network by Environment Canada's Ecological Monitoring and Assessment Network Coordinating Office and the Canadian Nature Federation. Information on research prepared in support of network establishment is presented along with a discussion of the potential of the network.     

Environmental Specimen Bank in Ehime University (es-BANK), Japan for global monitoring

During the last 40 years, The Center for Marine Environmental Studies (CMES), Ehime University collected a variety of environmental and biological material comprising about 1000 species and 100,000 samples from many developing and developed countries and also open seas and oceans all over the world. They were categorically archived, catalogued and stocked in our Environment Specimen Bank (es-BANK) facility equipped with a -25 degrees C cold room. We have already exchanged specimens with many scientific institutions and are also eager to widen our collaboration with other specimen banks. In our survey using the air, water, wildlife and human samples, we found that the major emission sources for the industrial chemicals like polychlorinated biphenyls (PCBs) are in the developed nations while those of organochlorine (OC) pesticides like dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), etc. are located in developing countries. However, significant emission of modern environmental contaminants such as polybrominated diphenyl ethers (PBDEs) also seems to occur predominantly in countries with high economic growth rates. Apart from the modern incinerators and other industrial installations in developed nations, the compounds, like dioxins and related compounds (DRCs), were also found to be released in significant levels from the municipal solid waste dumping sites of developing countries. By evaluating the distribution patterns of various persistent toxic substances (PTSs) in our studies, we could conclude that DRCs and DDTs are regional contaminants, while PCBs, PBDEs, HCHs and hexachlorobenzene (HCB) are global contaminants. We also found that the pollution by PBDEs has been increasing in the last two decades while that of the legacy OCs has been decreasing.     

Brominated flame retardants in the environment of Asia-Pacific: an overview of spatial and temporal trends

In this paper, we summarize spatial and temporal trends of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in coastal and marine biota, and further assess human exposure to these brominated flame retardants (BFRs) in Asia-Pacific. The review is based mainly on the studies that were conducted in our laboratory and utilized samples archived in the environmental specimen bank (es-BANK) of Ehime University, Japan. The studies suggest that the target BFRs are ubiquitous in the environment of Asia-Pacific. Examination of spatial trends reveals that concentrations of these contaminants are relatively high in samples from Korea, South China and Japan. In general, the magnitude of environmental contamination by PBDEs in Asia-Pacific, as well as human exposure to these contaminants, seem to be comparable to or slightly higher than in Europe, but lower than in North America. Evaluation of temporal trends in concentrations of BFRs in marine mammals from the coastal waters of Japan and China showed drastic increase during the last 30 years. These changes in BFR levels in samples from Japan were in line with trends in production/use of the commercial formulations. Since the withdrawal of some PBDE products from the Japanese market in the 1990s, concentrations of HBCDs appear to exceed those of PBDEs, reflecting increasing usage of HBCDs over PBDEs. The increasing environmental contamination by BFRs in Chinese coastal waters indicates that contamination by BFRs has already become evident, even in developing countries. In view of the rising environmental levels and the high consumption volume of BFRs in Asia, further efforts should be made to monitor environmental contamination by these chemicals in order to identify sources and reduce emissions.     

An assessment of persistent organic pollutants in Scottish coastal and offshore marine environments

Concentrations of persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were determined in sediment and biota (fish liver) from around Scotland. The concentrations were investigated using assessment criteria developed by OSPAR and ICES. Organic contaminant concentrations, PAHs, PCBs and PBDEs in sediment, and PCBs and PBDEs in fish liver, were significantly higher in the Clyde compared to all other sea areas. This is mainly due to historic industrial inputs. Highest PCB and PAH concentrations were found in the strata furthest up the Clyde estuary, with concentrations of POPs in these strata being at levels such that there is an unacceptable risk of chronic effects occurring in marine species. Furthermore, for PAHs in Clyde sediment there was a significant negative gradient going from north to south towards the open sea. PAH and PCB concentrations in sediment and biota in all other Scottish sea areas (except for PCBs in sediment from East Scotland) were unlikely to give rise to pollution effects, being below relevant assessment criteria. Although no assessment criteria are available for PBDEs, the concentrations observed in Scottish sediments were low with all congeners below the limit of detection (LoD; 0.03 μg kg(-1) dry weight) in 140 out of a total of 307 samples analysed. Where PBDEs were detected, the dominant congeners were BDE47 and BDE99. PBDEs were detected in fish livers, although concentrations were less than 150 μg kg(-1) lipid weight in all sea areas except the Clyde where concentrations ranged between 8.9 and 2202 μg kg(-1) lipid weight. Few trends were detected in contaminant concentrations in biota or sediment at any Scottish site with more than five years data. Downward trends were detected in PAHs in sediment from the Clyde, Irish Sea and Minches and Malin Sea and PCBs in fish liver from the Moray Firth. Rules were developed for the aggregation of the contaminant data across a sea area. An overall assessment for each sea area was then assigned, looking at the frequency of sites or strata within each sea area that were above or below the relevant assessment criteria. Overall the status of the various sea areas, with respect to the assessed POPs, can be considered to be acceptable in that they were below concentrations likely to result in chronic effects for all sea areas except the Clyde.     

Development of a New Approach to Cumulative Effects Assessment: A Northern River Ecosystem Example

If sustainable development of Canadian waters is to be achieved, a realistic and manageable framework is required for assessing cumulative effects. The objective of this paper is to describe an approach for aquatic cumulative effects assessment that was developed under the Northern Rivers Ecosystem Initiative. The approach is based on a review of existing monitoring practices in Canada and the presence of existing thresholds for aquatic ecosystem health assessments. It suggests that a sustainable framework is possible for cumulative effects assessment of Canadian waters that would result in integration of national indicators of aquatic health, integration of national initiatives (e.g., water quality index, environmental effects monitoring), and provide an avenue where long-term monitoring programs could be integrated with baseline and follow-up monitoring conducted under the environmental assessment process.     

凝胶渗透色谱-硅胶柱-气相色谱-负化学离子源质谱测定生物介质中49种BFRs类化合物

建立了生物介质内22种多溴联苯(PBBs)和27种多溴联苯醚(PBDEs)的净化和分析方法。通过分析不同时间段凝胶渗透色谱(GPC)洗脱液中49种化合物含量,得出不同化合物凝胶色谱洗脱曲线。样品经过凝胶渗透色谱-混合硅胶柱净化后,再使用GC-(NCI)/MS对样品进行检测。实验结果表明,PBBs和PBDEs检出限分别为0.02~0.88 pg/g和0.01~74.00 pg/g。对实验过程进行验证发现,样品不同浓度加标回收率为80%~120%,相对标准偏差小于20%。该方法具有良好的净化效果、准确度和精密度,拥有良好的线性范围及检出限,满足生物介质中溴代阻燃剂的检测分析实际要求。     

PBDE,HBCD, and novel brominated flame retardant contamination in sediments from Lake Maggiore (Northern Italy)

The reduction in the use of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) has opened the way for the introduction of novel brominated flame retardants (NBFRs) in place of the banned formulations. Important representatives of this group are decabromodiphenyl ethane (DBDPE), 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE), hexabromobenzene (HBB), and pentabromoethylbenzene (PBEB). In this study, the contamination due to NBRFs was investigated for the first time in Italy in the sediments of Lake Maggiore. The aim of the research was to characterize in detail the possible presence of temporal trends and/or to identify potential sources of contamination. The study also considered the PBDE and HBCD lake sediment’s current contamination. The analytical results showed that sediments in Lake Maggiore and its tributary rivers had weak concentrations of PBEB, HBB, and BTBPE, but they did not have a negligible/insignificant contamination of HBCD (up to 23.7 ng/g dry weight (d.w.)). The determination of PBDEs in sediments showed that BDE-209 was the predominant congener (up to 217 and 28 ng/g d.w. in river and lake sediments, respectively). DBDPE was detected in the sediments with relevant concentrations (up to 280 ng/g d.w in the River Boesio sediments). The positive correlation of DBDPE with BDE-209 confirmed the wide and important use of this compound in the Lake Maggiore basin and the hypothesis that this compound will soon become one of the most important NBFRs used in Northern Italy. The contamination of Lake Maggiore sediments due to PBDEs, HBCD, and NBFRs were comparable to other worldwide situations.     

Meat,Dairy and Climate Change: Assessing the Long-Term Mitigation Potential of Alternative Agri-Food Consumption Patterns in Canada

We use a newly developed model of the entire Canadian energy system (TIMES-Canada) to assess the climate change mitigation potential of different agri-food consumption patterns in Canada. For this, our model has been extended by disaggregating the agricultural demand sector into individual agri-food demands to allow for a more in-depth analysis. Besides a business-as-usual (baseline) scenario, we have constructed four different agri-food scenarios to assess the viability of reducing Canadian meat and dairy consumption in order to diminish Canada’s agricultural sector energy consumption and greenhouse gas (GHG) emissions. Our policy scenarios progressively restrict the consumption of different meat and dairy agricultural products until the year 2030. Our results suggest that the implementation of a meat and dairy consumption reduction policy would lead to a 10 to 40 % reduction in agricultural GHG emissions, depending on the severity of the scenario. This translates to a 1 to 3 % decrease in total Canadian GHG emissions by the year 2030. Besides these environmental benefits, health benefits associated with a reduction in meat and dairy consumption (as inferred from other studies) are presented as an additional source of motivation for implementing such a policy in Canada.