Review of Singapore's air quality and greenhouse gas emissions: Current situation and opportunities

Singapore has many environmental accomplishments to its credit. Accessible data on air quality indicates that all criteria pollutants satisfy both U.S. Environmental Protection Agency (EPA) and World Health Organization (WHO) air quality standards and guidelines, respectively. The exception is PM_2.5 (particles with an aerodynamic diameter ≤2.5 μm), which is not currently considered a criteria pollutant in Singapore but may potentially be the major local air pollution problem and cause for health concern. Levels of other airborne pollutants as well as their physical and chemical processes associated with local formation, transformation, dispersion, and deposition are not known. According to available emission inventories, Singapore's contribution to the total atmospheric pollution and carbon budget at the regional and global scales is small. Emissions per unit gross domestic product (GDP) are low compared with other countries, although Singapore's per-capita GDP and per-capita emissions are among the highest in the world. Some information is available on health effects, but the impacts on the ecosystem and the complex interactions of air pollution and climate change at a regional level are also unknown. This article reviews existing available information on atmospheric pollution and greenhouse gas emissions and proposes a multipollutant approach to greenhouse gas mitigation and local air quality. Singapore, by reducing its per-capita emissions, increasing the availability of information (e.g., through regularly publishing hourly and/or daily PM_2.5 concentrations) and developing a research agenda in this area, would likely be seen to be a model of a high-density, livable, and sustainable city in Southeast Asia and other tropical regions worldwide.

Implications Singapore is widely recognized for its environmental achievements and often cited as a model of a high-density, livable, and sustainable city. This article reviews available information with the aim to provide a reference for future scientific research of strategic relevance for Singapore's air quality and greenhouse gas mitigation management under a multipollutant framework. However, the limited publicly accessible data and little scientific information prevent a comprehensive assessment of the local air quality and greenhouse gas emissions. Singapore's dynamic economy and strong profile in advanced science and technological innovation have the potential to enhance the research agenda in this area, which is not yet well developed in tropical cities.     

Persistent organic pollutants (POPs): state of the science

The environmental chemistry and ecotoxicology of persistent organic pollutants (POPs) are fascinating areas of scientific research. Our objective in this paper is to provide a brief, focussed overview of what constitutes a POP, highlight the harmful effects they may have on biota, make some comments on their environmental sources and analysis, their environmental trends and processes, their movement through foodchains and highlight some important regional-and global-scale environmental transport issues. Finally, we offer some personal thoughts on some current and future areas of scientific enquiry on POPs.     

Comparative environmental assessment of biocides used in antifouling paints

In response to increasing scientific evidence on the toxicity and persistence of organotin residues from antifouling paints in the aquatic environment, the use of triorganotin antifouling products was banned on boats of less than 25 m length in many countries during 1987. Alternatives to tributyltin (TBT) paint are mainly copper based coatings containing organic booster biocides to improve the efficacy of the formulation, and have been utilised on small boats for the last 10 years. With policies encouraging a total ban on TBT, it is expected that these biocides will be used to a greater extent in the future. Limited data and information are available on the environmental occurrence, fate, toxicity, and persistence of these biocides, and thus any decisions on policies regulating antifoulants cannot be fully informed. In this study, a multicriteria comparison of alternative biocides, based on a general assessment of available information in the literature, provided support for the use of the precautionary principle with respect to policies on antifouling products. This assessment was validated by a more detailed comparison of four selected biocides and TBT. Results indicate that TCMS pyridine and TCMTB demonstrate environmental characteristics similar to TBT and thus detail risk assessments are needed before their use is permitted. The widespread use of the other biocides should be allowed only after research to fill the gaps in knowledge with respect to their toxicity and persistence in aquatic environments.     

Multilingual education of students on a global scale and perspective—international networking on the example of bioindication and biomonitoring (B&B technologies)

Living or formerly living organisms are being used to obtain information on the quality of the general health status of our environment by bioindication and biomonitoring methods for many decades. Thus, different roads toward this common scientific goal were developed by a lot of different international research groups. Global cooperation in between various scientific teams throughout the world has produced common ideas, scientific definitions, and highly innovative results of this extremely attractive working field. The transdisciplinary approach of different and multifaceted scientific areas—starting from biology, analytical chemistry, via health physics, up to social and economic issues—have surpassed mental barriers of individual scientists, so that “production” of straightforward common results related to the influence of material and immaterial environmental factors to the well-being of organisms and human life has now reached the forefront of international thinking. For the further sustainable development of our common scientific “hobby” of bioindication and biomonitoring, highest personal energy has to be given by us, being teachers to our students and to convince strategically decision makers as politicians to invest (financially) into the development of education and research of this innovative technique. Young people have to be intensively convinced on the “meaning” of our scientific doing, e.g., by extended forms of education. One example of multilingual education of students on a global scale and perspective is given here, which we started about 3 years ago.     

The Relationship between Historic Industrial Site Use and Environmental Contamination

ABSTRACT

A methodology is presented for estimating the probability that particular classes of environmental contaminants will be of concern at brownfield redevelopment sites. These probabilities are predicted by a logistics model that is based on qualitative information about site history and status. This qualitative information comprises data that would be collected through a Phase I Environmental Site Assessment (ESA), including historic site use, current use and ownership status, and the nature of adjacent properties. The model is fit and demonstrated using a set of 59 former industrial sites in southwestern Pennsylvania that were collected from the files of the Pennsylvania Department of Environmental Protection (PADEP). Predictive models are developed for exceedances of contaminants as grouped into the following classes: metals, chlorinated hydrocarbons, fuel hydrocarbons, and PCBs. A procedure for estimating the parametric uncertainty of the model predictions is also illustrated. This method can serve as a starting point for more effective usage of existing Phase I ESA information and for evaluation of the benefit of obtaining additional site information. By increasing the decision-making value of existing (or inexpensive) data, this method can help to reduce the information asymmetry that may be an obstacle to redevelopment.     

Interactive valuation: the social construction of the value of ecological services

Two different perspectives mark the discourse about the valuation of ecological services: a positivistrealist perspective, emphasising the use of objective scientific procedures to discover true values of ecological services truth is seen as the basis for social change; and a constructivist perspective, emphasising value as emerging from interaction. Value is an agreement and hence effective in social change. This paper examines the implications of the latter for valuation. It first analyses the current dominant practice of environmental valuation in terms of its epistemological assumptions. It then examines how a constructivist perspective colours the expectation of societal effectiveness of environmental valuation. Both themes reflect debated issues in ecological economics (e.g. O'Connor, 1998). 'Double hermeneutics' refers to the capacity to make sense on the basis of the sense-making of others. Environmental valuation in economics attempts a sort of 'triple hermeneutics': economists make sense of how people value the environment, in order to influence the sense-making of policy-makers and the general public. This paper argues that environmental valuation alternatively can be carried out as a constructivist procedure that reduces triple to single hermeneutics. Environmental valuation aims at societal change through internalisation of the costs of ecological services. Knowledge of the 'real' costs is expected to influence behaviour. Our analysis calls for the wider use of an alternative approach 'interactive valuation'. That is, the people whose behaviour incurs environmental costs are assisted to use environmental valuation methods themselves in order experientially to learn to internalise the environmental costs of their activities. It is not the researcher or expert who analyses and learns, so that he/she can transfer the learning to others, but the 'others' themselves who analyse and learn. In practice, this means that scientific valuators are not limited to discovering 'real', objective values, but also engage in developing tools for discovery learning by people themselves. The paper elaborates concrete experiences in the analysis and development of farming systems.     

Biogas production from anaerobic digestion of food waste and relevant air quality implications

Biopower can diversify energy supply and improve energy resiliency. Increases in biopower production from sustainable biomass can provide many economic and environmental benefits. For example, increasing biogas production through anaerobic digestion of food waste would increase the use of renewable fuels throughout California and add to its renewables portfolio. Although a biopower project will produce renewable energy, the process of producing bioenergy should harmonize with the goal of protecting public health. Meeting air emission requirements is paramount to the successful implementation of any biopower project. A case study was conducted by collecting field data from a wastewater treatment plant that employs anaerobic codigestion of fats, oils, and grease (FOG), food waste, and wastewater sludge, and also uses an internal combustion (IC) engine to generate biopower using the biogas. This research project generated scientific information on (a) quality and quantity of biogas from anaerobic codigestion of food waste and municipal wastewater sludge, (b) levels of contaminants in raw biogas that may affect beneficial uses of the biogas, (c) removal of the contaminants by the biogas conditioning systems, (d) emissions of NO_x, SO₂, CO, CO₂, and methane, and (e) types and levels of air toxics present in the exhausts of the IC engine fueled by the biogas. The information is valuable to those who consider similar operations (i.e., co-digestion of food waste with municipal wastewater sludge and power generation using the produced biogas) and to support rulemaking decisions with regards to air quality issues for such applications.

Implications: Full-scale operation of anaerobic codigestion of food waste with municipal sludge is viable, but it is still new. There is a lack of readily available scientific information on the quality of raw biogas, as well as on potential emissions from power generation using this biogas. This research developed scientific information with regard to quality and quantity of biogas from anaerobic co-digestion of food waste and municipal wastewater sludge, as well as impacts on air quality from biopower generation using this biogas. The need and performance of conditioning/pretreatment systems for biopower generation were also assessed.     

Towards integrated environmental assessment support for the European Community's environmental action programme process

This paper firstly discusses the strategy for integrated environmental assessment (IEA) at the European Environment Agency (EEA), addressing the principles, definition and scope, and summarising the state of the art. The IEA process is described within the framework of the DPSIR concept a chain of causal links going from Driving Forces, Pressures, States to Impacts, which finally leads to political Responses. A key objective of IEA is to facilitate the framing and implementation of policies and strategies. Secondly, the paper summarises the results of the first broader exercise of IEA at the EEA an environmental assessment of the European Community's Fifth Action Programme. Although limited in scope, the exercise provides lessons to be learned. Therefore, the paper concludes, assessments should be validated and be based on the most up-to-date findings, and links need to be created and maintained with the appropriate scientific/research communities. The IEA concept and its approaches should be further elaborated on a European scale according to prominent environmental problems that have a transboundary or a multi-national character. Cost-benefit studies should be enhanced. Finally, improved information is required on the DPSIR framework, including the interrelationship between the economic and environmental systems.     

A regulatory view on science and predictive models

A lot of scientific knowledge is required to carry out and enforce environmental regulations. The paper deals with the relationship between law and science from a legal perspective. First, some difficulties in using science to carry out environmental regulations are outlined. After this, some legal concepts which try to cope with the problems are presented. Aspects discussed are the precautionary principle, the legal concept of 'state of the art', general standard setting, the flexibility of the regulations, and procedural regulations for the standard-setting process. Finally, the new challenge for science that derives from the legal demand of an integrated approach to environmental protection is addressed.     

Urban environmental geochemistry of trace metals

As the world's urban population continues to grow, it becomes increasingly imperative to understand the dynamic interactions between human activities and the urban environment. The development of urban environmental geochemistry has yielded a significant volume of scientific information about geochemical phenomena found uniquely in the urban environment, such as the distribution, dispersion, and geochemical characteristics of some toxic and potentially toxic trace metals. The aim of this paper is to provide an overview of the development of urban environmental geochemistry as a field of scientific study and highlight major transitions during the course of its development from its establishment to the major scientific interests in the field today. An extensive literature review is also conducted of trace metal contamination of the urban terrestrial environment, in particular of urban soils, in which the uniqueness of the urban environment and its influences on trace metal contamination are elaborated. Potential areas of future development in urban environmental geochemistry are identified and discussed.     

Environmental and public health co-benefits of consumer switches to immunity-supporting food

During COVID-19, there has been a surge in public interest for information on immunity-boosting foods. There is little scientific support for immunity-supporting properties of specific foods, but strong evidence for food choice impacts on other health outcomes (e.g. risk of non-communicable disease) and environmental sustainability. Here, we relate online recommendations for “immunity-boosting” foods across five continents to their environmental and human health impacts. More frequently recommended food items and groups are plant based and have lower land use and greenhouse gas emission impacts plus more positive health outcomes (reducing relative risks of mortality or chronic diet-related diseases) per serving of food. We identify trade-offs between environmental outcomes of increasing consumption of recommended food items, with aquatic environment impacts increasing with food recommendation frequency. People’s reliance on the Internet for health information creates an opportunity to consolidate behaviour change towards consuming foods with multiple co-benefits. Our study identifies win–win options for nudging online information-seeking behaviour towards more sustainable choices for terrestrial biodiversity conservation and human health.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01693-w.     

Practices,perceptions, and implications of fertilizer use in East-Central China

Face-to-face interviews (n = 553) were conducted in five counties in East-Central China to study farmers’ fertilizer application behaviors, decision-making processes, attitudes towards adopting better fertilizer application technologies, and environmental consciousness. The survey results revealed widespread fertilizer misapplication and highly variable application behaviors in the study regions. The lack of scientific knowledge on fertilizers and the absence of guidance from agricultural extension services have forced the farmers to rely on personal judgment and advice from fertilizer dealers and friends to make decisions in fertilizer application. Overall, farmers have been idiosyncratic in fertilizer application with limited adoption of better fertilizer application technologies. There are great potentials for reducing pollutant load from agricultural runoff through promoting scientific fertilizer application in the regions. However, farmers’ diverse preferences over agricultural extension programs necessitate an integrated approach emphasizing farmer involvement throughout the development of such programs for promoting better fertilizer application practices.     

中国海洋环境污染监测的回顾与展望

海洋环境污染监测是海洋环境管理的“耳目”和“哨兵”．离开海洋环境污染监测．海洋环境管理将寸步难行。在过去１５年中,中国海洋环境污染监测工作取得了长足的进步,集中表现在三个方面：一是形成了从国家海洋环境监测中心一海区监测中心－管区－监察站的四级海洋环境监测体系;组建了由国务院有关部委、沿海１１个省（市）、自治区等有关部门１００多个单位２５００人参加的全国海洋环境污染监测网;每年获取各类海洋环境污染监测数据十万余个,提供了估计全国海洋环境形势的基础。二是海洋环境污染监测工作有中国的特色。组织上实行了优化布点、分级管理,初步形成了有特色的监测网络体系;技术上推行站点网络化、布点采样规范化、分析方法标准化、数据处理计算机化、质量保证工作系统化规范化,具有自己特色的技术路线正在形成;管理上逐渐走上科学管理的道路。三是为海洋环境管理服务的能力有了明显提高。该文概略地介绍了中国海洋环境污染监测工作的全貌,全面地总结了中国海洋环境１５年来的十条宝贵经验,宏观地描述了未来中国海洋环境污染监测的发展方向。     

A three-step approach to minimise the impact of a mining site on vicuña (<Emphasis Type="Italic">Vicugna vicugna</Emphasis>) and to restore landscape connectivity

Resource extraction projects generate a diversity of negative effects on the environment that are difficult to predict and mitigate. Consequently, adaptive management approaches have been advocated to develop effective responses to impacts that were not predicted. Mammal populations living in or around mine sites are frequently of management concern; yet, there is a dearth of published information on how to minimise the negative effects of different phases of mining operations on them. Here, we present the case study of a copper mine in the Chilean Altiplano, which caused roadkills of the protected vicuña (Vicugna vicugna). This issue led to a three-step solution being implemented: (1) the initial identification of the problem and implementation of an emergency response, (2) the scientific analysis for decision making and (3) the planning and informed implementation of responses for different future scenarios and timescales. The measures taken under each of these steps provide examples of environmental management approaches that make use of scientific information to develop integrated management responses. In brief, our case study showed how (1) the timescale and the necessity/urgency of the case were addressed, (2) the various stakeholders involved were taken into account and (3) changes were included into the physical, human and organisational elements of the company to achieve the stated objectives.     

易腐性有机垃圾的产生与处理技术途径比较

我国城市垃圾以易腐性有机垃圾为主.目前有关管理部门提出逐步减少进入填埋场的易腐性有机垃圾量,因此,必须寻求其他填埋替代技术消纳易腐性有机垃圾物流.本文对几种常规技术方案进行了比较.认为应该根据非餐饮业和餐饮业易腐性有机垃圾各自的产生源特点,采取不同的处理方案;但目前这些替代技术用于处理易腐垃圾时均存在各自的缺陷.本文据此提出了相应的技术完善要求和配套管理政策建议.     

基于水动力数值模型的港口规划累积影响评价

累积影响评价是战略环境评价的主要方法和重要内容之一,但目前还缺乏通用的评价程序和方法.通过识别港口规划的累积影响源和途径,建立了基于水动力数值模型的累积影响评价的量化评估和分析框架.以厦门港嵩屿港区规划为例,通过对海湾纳潮量及各敏感点流速的模拟,计算淤积量及其分布变化,进而推测海域水质和底质变化,并分析了由此引起的海洋生物群落的变化趋势.通过比较不同岸线方案的累积影响,为港区岸线优选提供了科学判据.实践表明,该方法框架综合运用定量预测和定性分析手段,其结果能为港口规划的战略环境评价提供科学依据.     

Knowledge transfer between researchers and practitioners in SUCOZOMA

A primary aim of the SUCOZOMA research program has been the transfer of knowledge from the scientific community to research users. This paper describes the intentions and ambitions regarding knowledge transfer within the program, reflecting the aim of its financier, the Swedish Foundation of Strategic Environmental Research, but also a general trend within research policy. The study investigates the areas in which SUCOZOMA has actively tried to transfer knowledge, reaching out to management and different practitioners. Many examples of communication and participation of research users in the program are described. The paper also identifies the bottlenecks and limits to communication.     

Fine particles and oxidant pollution: developing an agenda for cooperative research

This paper describes a background for the North American Research Strategy for Tropospheric Ozone (NARSTO) cooperative program integrating studies of O3 and PM2.5. It discusses several important aspects for rationalizing NARSTO's trinational investigative approach, including (1) an outlook on the state of knowledge about fine particles in the troposphere and their origins in Canada, Mexico, and the United States; (2) the need for enhancement and strengthening of key field measurements in relation to tropospheric chemistry and a health effects component; and (3) the use of a central theme for advancing air quality modeling using evolving techniques to integrate and guide key process-oriented field campaigns. The importance of organizing a scientific program to acquire "policy-relevant" information is stressed, noting cooperative research directions that address combined PM2.5 and O3 issues, illustrated through exploration of hypothetical pathways of PM2.5 response to choices of O3 and PM precursor emission reductions. The information needed for PM2.5 research is noted to intersect in many cases with those of O3, but diverge in other cases. Accounting for these distinctions is important for developing NARSTO's strategy over the next decade.     

The influence on partial order ranking from input parameter uncertainty. Definition of a robustness parameter

The method of partial order ranking has been used within the environmental area for a variety of purposes as an attractive way of handling complex information. However, the environmental data are often associated with a significant degree of uncertainty. In this investigation the general nature of the influence from data uncertainty on the partial order ranking is analyzed. A Monte Carlo type analysis is performed in which a series of randomly formed data are used to test the influence of data uncertainty. The partial order ranking is interpreted, where the results are transferred to a one-dimensional ranking scale taking into account that not all elements are ranked with the same certainty. A simple general robustness parameter (E) in form of the expected number of comparisons for each ranking element is defined and correlated to the uncertainty analysis results. A simple equation relates E to the number of elements and the number of parameters, respectively. The magnitude of the ranking uncertainty is shown to increase rapidly when the E value decreases below 4-5 comparisons per element. When the E value exceeds 5 the ranking uncertainty becomes nearly constant and independent on the actual E value.