Systematic Review of the Health and Equity Impacts of Remediation and Redevelopment of Contaminated Sites

Integrating portable X-ray fluorescence site survey and ArcGIS models for rapid risk assessment and mitigation strategies at an abandoned arsenic mine site: a case study

Australia's metalliferous abandoned mine sites (MAMSs), pose tangible threats to the environment and human health. To address these concerns, our study utilised state-of-the-art handheld XRF technology to conduct a real-time assessment of the Mole River arsenic mine site. The data revealed notably elevated levels of arsenic and manganese, with the southeast corner of the site identified as a contaminant hotspot. We used a tiered risk assessment approach to compare the detected contaminant concentrations to the Australian health investigation levels (tier 1). This led us to a broader examination of erosion vulnerabilities and the potential migration of contaminants (tier 2). Further, a hydrological assessment (tier 3) identified significant erosion in southern regions, indicating the potential for contaminants to be transported off-site through surface water runoff to Sam's Creek and Mole River. The proximity of a reservoir to these runoff pathways brought forth additional challenges, especially during heavy rainfall events. Subsequent laboratory analysis of water samples reinforced our findings, as they confirmed heightened arsenic concentrations in Mole River downstream, accentuating the potential risks to ecosystems and human health. By integrating the XRF contour map and erosion assessment with the RUSLE model, valuable insights are gained into critical hotspots with high contamination and erosion potential. By directing rehabilitation efforts towards critical hotspots, resources can be allocated more efficiently and cost-effectively.

Death and hospital contact in a cohort from Thyborøn-Harboøre an environmentally contaminated site in Denmark

We studied mortality and hospital contact in people from Thyborøn-Harboøre, an environmentally contaminated fishing community on the Danish West Coast. The population and a comparison group from other fishing communities on the Danish West Coast were identified from historical data in the Central Population Register. All persons were followed up for death and hospital contacts to March 2023. Event rates were compared with Poisson regression; adjusted rate ratios (aRR); and 95% confidence interval (CI). The old cohort included inhabitants in Thyborøn-Harboøre in 1968-1970 before pollution was controlled; 4914 persons/2485 deaths. All-cause mortality, aRR 1.06 (95% CI 1.01-1.11), and cancer mortality, aRR 1.17 (95% CI 1.05-1.30), were elevated; especially for kidney cancer aRR 1.82 (95% CI 1.07-3.12). Hospital contacts were elevated for psychiatric disorders; with an aRR of 4.07 (95% CI 1.41-11.72) for anxiety in men. As there is still considerable concern in the area about possible health consequences from stored chemicals, we included also a new cohort of newborn and immigrants to the area in 1990-2006; 2933 persons/302 deaths. All-cause mortality, aRR 1.26 (1.11-1.43) (men 1.15 and women 1.44), and cancer mortality, aRR 1.47 (95% CI 1.14-1.89) were elevated. Hospital contacts were elevated for ischemic heart disease/heart attack and indicated for autism/obsessive compulsory disorder in boys. In conclusion, mortality data confirmed incidence data of excess kidney cancer in the old cohort. The new cohort had a generally elevated mortality, possibly indicating selective immigration from other parts of Denmark. However, the new cohort is still relatively young, and the mortality pattern needs to be monitored.

Understanding Nanoscale Interactions between Minerals and Microbes: Opportunities for Green Remediation of Contaminated Sites

In situ contaminant degradation and detoxification mediated by microbes and minerals is an important element of green remediation. Improved understanding of microbe-mineral interactions on the nanoscale offers promising opportunities to further minimize the environmental and energy footprints of site remediation. In this Perspective, we describe new methodologies that take advantage of an array of multidisciplinary tools─including multiomics-based analysis, bioinformatics, machine learning, gene editing, real-time spectroscopic and microscopic analysis, and computational simulations─to identify the key microbial drivers in the real environments, and to characterize in situ the dynamic interplay between minerals and microbes with high spatiotemporal resolutions. We then reflect on how the knowledge gained can be exploited to modulate the binding, electron transfer, and metabolic activities at the microbe-mineral interfaces, to develop new in situ contaminant degradation and detoxication technologies with combined merits of high efficacy, material longevity, and low environmental impacts. Two main strategies are proposed to maximize the synergy between minerals and microbes, including using mineral nanoparticles to enhance the versatility of microorganisms (e.g., tolerance to environmental stresses, growth and metabolism, directed migration, selectivity, and electron transfer), and using microbes to synthesize and regenerate highly dispersed nanostructures with desired structural/surface properties and reactivity.

Using L. minor and C. elegans to assess the ecotoxicity of real-life contaminated soil samples and their remediation by clay- and carbon-based sorbents

Toxic substances, such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals, can accumulate in soil, posing a risk to human health and the environment. To reduce the risk of exposure, rapid identification and remediation of potentially hazardous soils is necessary. Adsorption of contaminants by activated carbons and clay materials is commonly utilized to decrease the bioavailability of chemicals in soil and environmental toxicity in vitro, and this study aims to determine their efficacy in real-life soil samples. Two ecotoxicological models (Lemna minor and Caenorhabditis elegans) were used to test residential soil samples, known to contain an average of 5.3, 262, and 9.6 ppm of PAHs, lead, and mercury, for potential toxicity. Toxicity testing of these soils indicated that 86% and 58% of soils caused ≤50% inhibition of growth and survival of L. minor and C. elegans, respectively. Importantly, 3 soil samples caused ≥90% inhibition of growth in both models, and the toxicity was positively correlated with levels of heavy metals. These toxic soil samples were prioritized for remediation using activated carbon and SM-Tyrosine sorbents, which have been shown to immobilize PAHs and heavy metals, respectively. The inclusion of low levels of SM-Tyrosine protected the growth and survival of L. minor and C. elegans by 83% and 78%, respectively from the polluted soil samples while activated carbon offered no significant protection. These results also indicated that heavy metals were the driver of toxicity in the samples. Results from this study demonstrate that adsorption technologies are effective strategies for remediating complex, real-life soil samples contaminated with hazardous pollutants and protecting natural soil and groundwater resources and habitats. The results highlight the applicability of these ecotoxicological models as rapid screening tools for monitoring soil quality and verifying the efficacy of remediation practices.

Sliding scales for assessing and communicating human and ecological risks and complexities for restoration, remediation crises, and decisions

Many lands were degraded or destroyed by human activities, including contamination from industry and military facilities. The United States and other industrialized counties have legacy wastes remaining from the Second World War, the Cold War, and industrialization. There is increasing need to return degraded land to suitable future land uses, including ecological parks and preserves. This paper proposes a conceptual model of the different levels of information needed to understand the risk to human health, the environment, and ecological resources. I propose a four-part approach: 1) general model for assessing ecological resources, 2) model for assessment needed for remediation or restoration projects, 3) a sliding scale, conceptual model for causes, events, and sources that lead to exposure and risk, and 4) an additional step that includes environmental justice (equity, diversity and inclusion) as a necessary consideration of traditional exposure assessment. While the factors involved in ecological risk assessment are well established, the combination of human health, ecological health, and environmental justice determining risk for remediation or restoration projects is not. Major factors useful for human health, environmental, and ecological evaluation include causes, events (earthquakes, accidents, chemical releases), sources, exposure, and informational challenges, as well as barriers to exposure. I propose that exposure through an environmental justice (diversity, equity, and inclusion) lens should be a key component of risk assessment. Each of these factors involves a sliding scale or continuum that must be considered in evaluating risk and communicating with the regulators, resource trustees, land managers and the public. The conceptual model also serves as a template for obtaining information about the environment that will be useful for communicating the importance of different risk factors. The model was developed for consideration of remediation on Department of Energy lands, it can be applied more broadly to other projects.

Managing Health Concerns Related to Post-Industrial Sites Redevelopment: A Warsaw, Poland Case Study

An important issue in the redevelopment of post-industrial sites, e.g., into housing, is the resolution of contaminated land issues, including health risks and environmental protection. The purpose of this article is to examine awareness of this aspect from the perspective of city or such site residents, using Warsaw as an example. Using a survey-style form data collection technique, a total of 55 fully completed survey questionnaires were collected and analysed using cross-tabulation. Furthermore, a desk research methodology was used to study the availability of sources on industrial areas and their transformation from the perspective of different stakeholder groups involved in the development of such areas in Poland. Similarly, information management was assessed from the viewpoint of information communities participating or being affected by redevelopment processes. The survey results evidenced that respondents are aware that post-industrial sites may be contaminated, but do not associate the possibility of potential health risks when residing on or near such sites. The analysis of the management of information on the reurbanisation of post-industrial sites in urban areas in Poland, including the availability of data on location and contamination, revealed a problematic data flow between central and local level authorities and mootable consistency of legal acts. Public awareness of negative phenomena, such as contamination and the consequent health risks associated with dwelling in such sites, can positively influence, as an input to monitoring and enforcement, the actions taken by other stakeholders in the clean-up processes of contaminated sites and force improvements in the management of such information. The flow of information, the activities forming the information function, and the decision-making process can be improved by technologies, such as spatial information systems and their infrastructures, by facilitating the integration of data from multiple sources and consequently enabling the analysis to be extended to include further relevant data.