Modeling human exposures to air pollution control (APC) residues released from landfills in England and Wales

Dynamics of PM2.5 pollution in the vicinity of the old municipal solid waste dumpsite

The present study explored the effect of local meteorology on the dispersion of PM_2.5 from a 30-year open municipal solid waste (MSW) dumpsite in Chennai, India. The spatial monitoring was conducted in and around the dumpsite to understand the impacts of dumpsite activities on the nearby residential area. Results showed that dumpsite activities are responsible for deteriorating local air quality. The 24-h average PM_2.5 concentrations were 50, 43.7, and 34 µg m^-3 during stagnation, recirculation, and ventilation events, respectively. Spearman's correlation showed an inverse relationship between PM_2.5 and temperature; wind speed indicated dispersion of fine aerosols. The observed inverse relationship between PM_2.5 and relative humidity indicated the hygroscopic growth of fine aerosols in the study area. We used AERMOD to simulate the dispersion of 1-h, 8-h, and 24-h PM_2.5 emissions from open waste burning in the dumpsite. The 1-h, 8-h, and 24-h simulated results showed the maximum concentration of 247, 136, and 53.4 µg m^-3 in the dumpsite, and concentration levels ranged between 50-60, 30-50, and 10-20 µg m^-3 were observed in the nearby residential area. The AERMOD predictions indicated that open waste burning could be a significant contributor to high PM_2.5 concentration in an adjacent residential area of the dumpsite.

Model for assessing health damage from air pollution in quarrying area - Case study at Tan Uyen quarry, Ho Chi Minh megapolis, Vietnam

Vietnam has a great demand for stone exploitation for the development of the country's infrastructure, reaching 181 million m³ in 2020. Mining activities are always accompanied by environmental pollution, negatively affecting public health. To accurately assess the level of pollution, as well as quantify the effect of air pollution on human health, a number of structures, methods, and models provide tools to assess the benefits of this control for public health and related economic values. However, there has been no research in Vietnam applied specifically to this type of stone exploitation. This study offers a model to evaluate the economic damage caused by dust exposure from activities related to quarrying, overcoming the lack of continuous monitoring data. The area selected for research is Binh Duong province, in the Ho Chi Minh megapolis, Vietnam, which has two construction quarries, Thuong Tan and Tan My, with a current annual production of approximately 4–5 million m³. The calculation results show that the damage to human health is estimated at approximately 9,643 billion dong a year, equivalent to 15.03 million USD. In addition, if the standard criteria are tightened, damage will continue to increase. This study also analyses some of the difficulties and limitations in the modelling process.

Can washing-pretreatment eliminate the health risk of municipal solid waste incineration fly ash reuse?

Although the reuse of washing-pretreated MSWI fly ash bas been a hot topic, the associated risk is still an issue of great concern. The present study investigated the influence of washing-pretreatment on the total contents and bioaccessibility of heavy metals in MSWI fly ash. Furthermore, the study incorporated bioaccessibility adjustment into probabilistic risk assessment, to quantify the health risk from multi-pathway exposure to the concerned chemicals as a result of reusing washed MSWI fly ash. The results revealed that both water-washing and acid-washing process have resulted in the concentrated heavy metal content, and have reduced the bioaccessibility of heavy metals. Besides, the acid-washing process increased the cancer risk in most cases, while the effect of water-washing process was uncertain. However, both water-washing and acid-washing pretreatment could decrease the hazard index based on bioaccesilbility. Despite the uncertainties accompanying these procedures, the results indicated that, in this application scenario, only water-washing or acid-washing process cannot reduce the actual risk from all samples to acceptable level, especially for cancer risk.

Municipal Solid Waste Management using Geographical Information System aided methods: a mini review

Municipal Solid Waste Management (MSWM) is one of the major environmental challenges in developing countries. Many efforts to reduce and recover the wastes have been made, but still land disposal of solid wastes is the most popular one. Finding an environmentally sound landfill site is a challenging task. This paper addresses a mini review on various aspects of MSWM (suitable landfill site selection, route optimization and public acceptance) using the Geographical Information System (GIS) coupled with other tools. The salient features of each of the integrated tools with GIS are discussed in this paper. It is also addressed how GIS can help in optimizing routes for collection of solid wastes from transfer stations to disposal sites to reduce the overall cost of solid waste management. A detailed approach on performing a public acceptance study of a proposed landfill site is presented in this study. The study will help municipal authorities to identify the most effective method of MSWM.

Soil quality assessment under emerging regulatory requirements

New and emerging policies that aim to set standards for protection and sustainable use of soil are likely to require identification of geographical risk/priority areas. Soil degradation can be seen as the change or disturbance in soil quality and it is therefore crucial that soil and soil quality are well understood to protect soils and to meet legislative requirements. To increase this understanding a review of the soil quality definition evaluated its development, with a formal scientific approach to assessment beginning in the 1970s, followed by a period of discussion and refinement. A number of reservations about soil quality assessment expressed in the literature are summarised. Taking concerns into account, a definition of soil quality incorporating soil's ability to meet multifunctional requirements, to provide ecosystem services, and the potential for soils to affect other environmental media is described. Assessment using this definition requires a large number of soil function dependent indicators that can be expensive, laborious, prone to error, and problematic in comparison. Findings demonstrate the need for a method that is not function dependent, but uses a number of cross-functional indicators instead. This method to systematically prioritise areas where detailed investigation is required, using a ranking based against a desired level of action, could be relatively quick, easy and cost effective. As such this has potential to fill in gaps and compliment existing monitoring programs and assist in development and implementation of current and future soil protection legislation.

Quantitative assessment of dust propagation at a hazardous waste landfill: directional monitoring with elemental analysis

The proportion of air pollution control (APC) residue in fugitive dust from the active cell of a hazardous waste landfill has been quantified using multi-element analytical data in combination with directional information about the dust samples collected. Passive sampling gauges (DustScan) were deployed at the periphery of the cell, and samples were collected at fortnightly intervals. They were scanned for dust coverage and direction, and sub-samples were digested using HF and HNO(3) prior to analysis for a range of metals using ICPAES. Dust samples were initially categorised on the basis of direction and distance with respect to the active cell, and overall colour. Independent graphical manipulation of the elemental data revealed separate dust populations with several demonstrably different inter-element ratios. These populations accord well with the initial dust characterisation, and consequent designation as "APC" and "background" has been confirmed by chemical comparison with grab samples from the active cell, the landfill clay and the topsoil cap. As well as allowing confident graphical discrimination between APC and background dusts, the technique provides datasets amenable to multivariate statistics. Principal component analysis followed by partial least-squares regression provides a rigorous way of investigating correlations within the data and predicting the explicable variance resulting from chosen end members. Element loadings on the first two components essentially confirm the results of the intuitive graphical approach. APC and clay/soil grab samples are successful signatures for PLS, for complementary sample groups. On the basis of both the intuitive and the statistical data handling, distinctive elemental ratios characteristic of APC and background dusts can be paired in order to define binary mixing trajectories, and thus quantify APC proportion in any individual sample. In one of the sampling intervals under consideration, some 65% APC was recorded close to the active cell margin, decreasing rapidly with dust fall out to 30% within a few hundred metres. This trial study indicates the potential of combining directional sampling with sensitive multi-element analysis to quantify fugitive dust from landfill and other facilities in the waste and industrial sectors.

Characterization and bioreactivity of respirable airborne particles from a municipal landfill

With an increasing population and greater pressure on land-use, the possible problems of landfilling are of increasing concern. These concerns include the possible adverse health effects arising from living in the vicinity of municipal solid waste (MSW) landfills. Human exposure to potential landfill emissions by respiratory, gastrointestinal or dermal mechanisms warrants further investigation. PM10 and PM2.5 from a UK landfill were physicochemically characterized and their bioreactivity screened by a plasmid scission assay in comparison with an urban PM collection. Preliminary data from human toxicology pathway-specific microarrays indicate landfill PM10 presents a comparable geobiological insult to urban PM10 in a human tracheobronchial tissue model.

Adapting EVIAVE methodology as a planning and decision-making tool in Venezuela

Landfills in Venezuela have serious problems regarding their location, design and operation. In fact, basic waste disposal is one of the main weaknesses of the municipal waste management in this country. The Venezuelan Ministry of Environment and Renewable Resources has studied and identified the negative impacts of operating landfills, but no program has been implemented to determine the cause-effect relation of these impacts or to design strategies to counteract with the serious environmental and health risks generated. This paper describes how EVIAVE methodology can be successfully used for landfill diagnosis, and shows how this type of landfill diagnosis was applied in Venezuela. For our research study, we carried out both a quantitative and qualitative evaluation of the environmental problems generated by 22 landfills in Venezuela. Our study was based on the following environmental indexes: Landfill Environment, Environmental Risk, Environmental Value, and Probability of Contamination. For the purposes of our study, it was first necessary to adapt EVIAVE to the legal system and social context in Venezuela. The results obtained confirmed the applicability of this methodology to Venezuelan landfills. EVIAVE was found to be an effective planning tool that provided crucial information for the development of action plans, which would improve landfill operation, and help make decisions pertaining to their closure, sealing and eventual recovery.

Exposure to heavy metals and PCDD/Fs by the population living in the vicinity of a hazardous waste landfill in Catalonia, Spain: health risk assessment

Most fly ashes produced in municipal waste incinerators of Catalonia (Spain) are deposited in a hazardous waste landfill (HWL) placed in Castellolí (Barcelona). This facility means a concern for the population living nearby. In response to this, we performed a probabilistic study focused on assessing human health risks derived from environmental exposure to heavy metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) around the HWL. Concentrations of various metals and PCDD/Fs were determined in soil and air samples collected at the HWL, and in 4 locations around it. Health risks were evaluated according to the distance from the sampling locations to the HWL (near and far-sites). In general terms, metal and PCCD/F levels were relatively low in air and soil samples. However, concentrations of PCDD/Fs, as well as those of some metals, were found to be relatively higher in the HWL and Castellolí (the nearest village) samples than in those collected far away, resulting in a slight increase of exposure to those pollutants. Anyhow, the current concentrations of metals and PCDD/Fs suggest that it is highly unlikely that there are any additional non-carcinogenic and carcinogenic risks for the population living near the HWL.

Loose-coupling an air dispersion model and a geographic information system (GIS) for studying air pollution and asthma in the Bronx, New York City

This study developed new procedures to loosely integrate an air dispersion model, AERMOD, and a geographic information system (GIS) package, ArcGIS, to simulate air dispersion from stationary sources in the Bronx, New York City, for five pollutants: PM(10), PM(2.5), NO(x), CO, and SO(2). Plume buffers created from the model results were used as proxies of human exposure to the pollution from the sources and they modified the commonly used fixed-distance proximity buffers by considering the realities of air dispersion. The application of the plume buffers confirmed that the higher asthma hospitalization rates were associated with the higher potential exposure to local air pollution. The air dispersion modeling exhibited advantages over proximity analysis and geostatistical methods for environmental health research. The loose integration provides a relatively simple and feasible method for health scientists to take advantage of both air dispersion modeling and GIS by avoiding the need for intensive programming and substantial GIS expertise.

Landfills in Jiangsu province, China, and potential threats for public health: leachate appraisal and spatial analysis using geographic information system and remote sensing

Waste disposal is of growing environmental and public health concern in China where landfilling is the predominant method of disposal. The assessment of potential health hazards posed by existing landfills requires sound information, and processing of a significant amount of spatial data. Geographical information system (GIS) and remote sensing (RS) are valuable tools for assessing health impacts due to landfills. The aims of this study were: (i) to analyze the leachate and gas emissions from landfills used for domestic waste disposal in a metropolitan area of Jiangsu province, China, (ii) to investigate remotely-sensed environmental features in close proximity to landfills, and (iii) to evaluate the compliance of their location and leachate quality with the relevant national regulations. We randomly selected five landfills in the metropolitan areas of Wuxi and Suzhou city, Jiangsu province, established a GIS database and examined whether data were in compliance with national environmental and public health regulations. The leachates of the sampled landfills contained heavy metals (Pb, As, Cr(6+) and Hg) and organic compounds in concentrations considered harmful to human health. Measured methane concentrations on landfill surfaces were low. Spatial analysis of the location of landfills with regard to distance from major water bodies, sensible infrastructure and environmental conditions according to current national legislation resulted in the rejection of four of the five sites as inappropriate for landfills. Our results call for rigorous evaluation of the spatial location of landfills in China that must take into consideration environmental and public health criteria.

Air pollution directional risk assessment for siting a landfill

Air pollution directional risk (APDR) is an essential factor to be assessed when selecting an appropriate landfill site. Because air pollutants generated from a landfill are diffused and transported by wind in different directions and speeds, areas surrounding the landfill will be subject to different associated risks, depending on their relative position from the landfill. This study assesses potential APDRs imposed from a candidate landfill site on its adjacent areas on the basis of the pollutant distribution simulated by a dispersion model, wind directions and speeds from meteorological monitoring data, and population density. A pollutant distribution map layer was created using a geographic information system and layered onto a population density map to obtain an APDR map layer. The risk map layer was then used in this study to evaluate the suitability of a candidate site for placing a landfill. The efficacy of the proposed procedure was demonstrated for a siting problem in central Taiwan, Republic of China.

Ambient air monitoring of Beijing MSW logistics facilities in 2006

In China, "green" integrated waste management methods are being implemented in response to environmental concerns. We measured the air quality at several municipal solid waste (MSW) sites to provide information for the incorporation of logistics facilities within the current integrated waste management system. We monitored ambient air quality at eight MSW collecting stations, five transfer stations, one composting plant, and five disposal sites in Beijing during April 2006. Composite air samples were collected and analyzed for levels of odor, ammonia (NH3), hydrogen sulfide (H2S), total suspended particles (TSPs), carbon monoxide (CO), sulfur dioxide (SO2), and nitrogen dioxide (NO2). The results of our atmospheric monitoring demonstrated that although CO and SO2 were within acceptable emission levels according to ambient standards, levels of H2S, TSP, and NO2 in the ambient air at most MSW logistics facilities far exceeded ambient limits established for China. The primary pollutants in the ambient air at Beijing MSW logistics facilities were H2S, TSPs, NO2, and odor. To improve current environmental conditions at MSW logistics facilities, the Chinese government encourages the separation of biogenic waste from MSW at the source.