Hazardous Waste Sites Research Articles

Global Water Pollution and Human Health

Water quality issues are a major challenge that humanity is facing in the twenty-first century. Here, we review the main groups of aquatic contaminants, their effects on human health, and approaches to mitigate pollution of freshwater resources. Emphasis is placed on chemical pollution, particularly on inorganic and organic micropollutants including toxic metals and metalloids as well as a large variety of synthetic organic chemicals. Some aspects of waterborne diseases and the urgent need for improved sanitation in developing countries are also discussed. The review addresses current scientific advances to cope with the great diversity of pollutants. It is organized along the different temporal and spatial scales of global water pollution. Persistent organic pollutants (POPs) have affected water systems on a global scale for more than five decades; during that time geogenic pollutants, mining operations, and hazardous waste sites have been the most relevant sources of long-term regional and local water pollution. Agricultural chemicals and waste-water sources exert shorter-term effects on regional to local scales.

Toward Identifying the Next Generation of Superfund and Hazardous Waste Site Contaminants

BackgroundThis commentary evolved from a workshop sponsored by the National Institute of Environmental Health Sciences titled “Superfund Contaminants: The Next Generation” held in Tucson, Arizona, in August 2009. All the authors were workshop participants.ObjectivesOur aim was to initiate a dynamic, adaptable process for identifying contaminants of emerging concern (CECs) that are likely to be found in future hazardous waste sites, and to identify the gaps in primary research that cause uncertainty in determining future hazardous waste site contaminants.DiscussionSuperfund-relevant CECs can be characterized by specific attributes: They are persistent, bioaccumulative, toxic, occur in large quantities, and have localized accumulation with a likelihood of exposure. Although still under development and incompletely applied, methods to quantify these attributes can assist in winnowing down the list of candidates from the universe of potential CECs. Unfortunately, significant research gaps exist in detection and quantification, environmental fate and transport, health and risk assessment, and site exploration and remediation for CECs. Addressing these gaps is prerequisite to a preventive approach to generating and managing hazardous waste sites.ConclusionsA need exists for a carefully considered and orchestrated expansion of programmatic and research efforts to identify, evaluate, and manage CECs of hazardous waste site relevance, including developing an evolving list of priority CECs, intensifying the identification and monitoring of likely sites of present or future accumulation of CECs, and implementing efforts that focus on a holistic approach to prevention.

Regulatory requirements and tools for environmental assessment of hazardous wastes: Understanding tribal and stakeholder concerns using Department of Energy sites

Many US governmental and Tribal Nation agencies, as well as state and local entities, deal with hazardous wastes within regulatory frameworks that require specific environmental assessments. In this paper we use Department of Energy (DOE) sites as examples to examine the relationship between regulatory requirements and environmental assessments for hazardous waste sites and give special attention to how assessment tools differ. We consider federal laws associated with environmental protection include the National Environmental Policy Act (NEPA), the Resource Conservation and Recovery Act (RCRA), the Comprehensive Environmental Response Compensation and Liability Act (CERCLA), as well as regulations promulgated by the Nuclear Regulatory Commission, Tribal Nations and state agencies. These regulatory regimes require different types of environmental assessments and remedial investigations, dose assessments and contaminant pathways. The DOE case studies illustrate the following points: 1) there is often understandable confusion about what regulatory requirements apply to the site resources, and what environmental assessments are required by each, 2) the messages sent on site safety issued by different regulatory agencies are sometimes contradictory or confusing (e.g. Oak Ridge Reservation), 3) the regulatory frameworks being used to examine the same question can be different, leading to different conclusions (e.g. Brookhaven National Laboratory), 4) computer models used in support of groundwater models or risk assessments are not necessarily successful in convincing Native Americans and others that there is no possibility of risk from contaminants (e.g. Amchitka Island), 5) when given the opportunity to choose between relying on a screening risk assessments or waiting for a full site-specific analysis of contaminants in biota, the screening risk assessment option is rarely selected (e.g. Amchitka, Hanford Site), and finally, 6) there needs to be agreement on whether there has been adequate characterization to support the risk assessment (e.g. Hanford). The assessments need to be transparent and to accommodate different opinions about the relationship between characterizations and risk assessments. This paper illustrates how many of the problems at DOE sites, and potentially at other sites in the U.S. and elsewhere, derive from a lack of either understanding of, or consensus about, the regulatory process, including the timing and types of required characterizations and data in support of site characterizations and risk assessments.

Subsurface detection of fossil fuel pollutants by photoionization and gas chromatography/mass spectrometry

This paper describes analysis of environmental pollutants at depth without bringing sample to the surface. It is based on an improved 3-stage Peltier freeze trap, which efficiently pre-concentrates volatile coal tar and petroleum hydrocarbons, and an integrated system for detecting pollutants on-line, in real-time by photoionization detection and quantitation by gas chromatography/mass spectrometry (GC/MS) as the probe is advanced into the subsurface. Findings indicate measurement precision and accuracy for volatiles meet EPA criteria for hazardous waste site investigations. When a Teflon membrane inlet is used to detect contaminants in groundwater, its 140 °C temperature limit restricts analyte collection in soil to C 2-phenanthrenes. Two case studies demonstrate the probe is well-suited to tracking petroleum and coal tar plumes from source to groundwater.

Mapping New Jersey: an evolving landscape

New is the first interpretive atlas of the state in more than one hundred years. New small in size with only 4.8 million acres, has a long and complex background. Its past is filled with paradoxes and contradictions - an agricultural economy for most of its history, New was also one of the earliest states to turn to manufacturing and chemical research. Today, still championing itself as the 'Garden State', New claims both the highest population density in the country and the largest number of hazardous waste sites. Many see an asphalt oasis, from the New Turnpike to the Garden State Parkway, with cities that sprawl into adjacent suburbs. Yet, after hundreds of years, large areas of New remain home to horse farms, cornfields, orchards, nurseries, blueberry bushes, and cranberry bogs. Tracing the changes in environment, land use patterns, demography, transportation, economy, and politics over the course of many centuries, Mapping New Jersey illuminates the state's transformation from a simple agricultural society to a post-industrial and culturally diverse place inhabited by more people per acre than anywhere else in the country. An innovator in transportation, from railroads to traffic circles to aviation, New from its beginning was a 'corridor' state, with a dense Native American trail system once crisscrossed on foot, country roads traveled by armies of the American Revolution, and, lately, the rolling wheels of many sedans, SUVs, hybrids, public and commercial vehicles, and freight. Early to industrialize, it also served as the headquarters for Thomas Edison and the development of the modern American economy. Small in territory and crowded with people, the state works to recycle garbage and, at the same time, best utilize and preserve its land. New has been depicted in useful and quite stunning historical maps, many of the best included in Mapping New Jersey - crude maps drawn by sixteenth-century navigators; complex and beautifully decorated pieces created by early Dutch cartographers; land maps plotted by seventeenth-century English settlement surveyors; examples of the nineteenth century's scientific revolution in map making that helped locate topography and important mineral resources; detailed insurance maps that correct London map maker William Faden's 1777-78 classic rendering of the state; and, aerial photos, remote sensing, and global positioning system maps generated through twenty-first-century technology breakthroughs in cartography. Integrating new maps, graphs, and diagrams unavailable through ordinary research or Internet searches, Mapping New Jersey is divided into six topical chapters, each accompanied by an introduction and overview telling the story of the state's past and detailing its diversity. Mapping New Jersey, dramatically bold and in full color, travels where New has gone and the rest of the nation is likely to follow.

PUSH TO RENEW SUPERFUND TAX

THE ENVIRONMENTAL PROTECTION Agency has written a letter to Congress supporting legislation that would renew the tax on chemical feedstocks and crude oil to pay for cleanups at Superfund hazardous waste sites. “Since the beginning of this Administration, we have made it clear that we support the reinstatement of the polluter pays system for the Superfund program,” wrote Mathy Stanislaus, EPA’s assistant administrator for solid waste and emergency response. “Today we are formalizing our call to Congress to pass this important legislation.” The tax was part of the original 1980 Superfund law. It imposed a charge on 42 industrial chemicals and every barrel of crude oil and included a corporate environmental income tax. That tax expired in 1995. If reimposed, it could cost companies about $1.7 billion annually. “By renewing the tax, the industries that had a hand in creating the problem—not taxpayers—will once again be held accountable for cleaning it up,” Rep. Earl Blumenauer ...

Evaluation of the Relationship between Pro-inflammatory Cyto-kines and Health Hazards in Workers Involved in Hazardous Waste Sites at Karnataka, India.

Most of the studies have reported higher occupational health haz¬ards on hazardous waste workers (HWW). However reports regarding the asso¬ciation between health hazards and pro-inflammatory cytokines in HWW are scanty. The present study was undertaken to evaluate the relationship between occupational health hazards and serum pro-inflammatory cytokines in HWW. One hundred two subjects working in hazardous waste areas in differ¬ent parts of Bangalore at Karnataka, India were enrolled into the study in 2009. Using questionnaire the respiratory morbidity and other work related problems in HWW was carried. The levels of pro-inflammatory cytokines in study subjects were determined by using Enzyme-linked-immunosorbent assay kits (Pierce Biotechnology, USA). The differences of serum pro-inflammatory cytokines levels between the groups were computed by using non-parametric Mann-Whitney U test. SPSS 10.0 for windows version of statistical software was used in the analy¬sis. The morbidity conditions such as respiratory (34%), musculo-skeletal (24.5%), past illnesses (12.7%), dermatological (11.8%), gastrointestinal (9.8%), injuries due to contact with sharp objects & heavy equipments (7.8%) and nose and eye (4.9%) problems were observed in HWW. The levels of serum pro-inflammatory cytokines such as IL-8 (P=0.041) & TNF-α (P=0.040) significantly increased in landfill area workers and subjects having respiratory symptoms. The levels of serum pro-inflammatory cytokines IL-8 & TNF- α were significantly associated with subjects having respiratory symptoms & further supporting that they are inflammatory markers in respiratory symptoms.

Computational Toxicology as Implemented by the U.S. EPA: Providing High Throughput Decision Support Tools for Screening and Assessing Chemical Exposure, Hazard and Risk

Computational toxicology is the application of mathematical and computer models to help assess chemical hazards and risks to human health and the environment. Supported by advances in informatics, high-throughput screening (HTS) technologies, and systems biology, the U.S. Environmental Protection Agency EPA is developing robust and flexible computational tools that can be applied to the thousands of chemicals in commerce, and contaminant mixtures found in air, water, and hazardous-waste sites. The Office of Research and Development (ORD) Computational Toxicology Research Program (CTRP) is composed of three main elements. The largest component is the National Center for Computational Toxicology (NCCT), which was established in 2005 to coordinate research on chemical screening and prioritization, informatics, and systems modeling. The second element consists of related activities in the National Health and Environmental Effects Research Laboratory (NHEERL) and the National Exposure Research Laboratory (NERL). The third and final component consists of academic centers working on various aspects of computational toxicology and funded by the U.S. EPA Science to Achieve Results (STAR) program. Together these elements form the key components in the implementation of both the initial strategy, A Framework for a Computational Toxicology Research Program (U.S. EPA, 2003), and the newly released The U.S. Environmental Protection Agency's Strategic Plan for Evaluating the Toxicity of Chemicals (U.S. EPA, 2009a). Key intramural projects of the CTRP include digitizing legacy toxicity testing information toxicity reference database (ToxRefDB), predicting toxicity (ToxCast) and exposure (ExpoCast), and creating virtual liver (v-Liver) and virtual embryo (v-Embryo) systems models. U.S. EPA-funded STAR centers are also providing bioinformatics, computational toxicology data and models, and developmental toxicity data and models. The models and underlying data are being made publicly available through the Aggregated Computational Toxicology Resource (ACToR), the Distributed Structure-Searchable Toxicity (DSSTox) Database Network, and other U.S. EPA websites. While initially focused on improving the hazard identification process, the CTRP is placing increasing emphasis on using high-throughput bioactivity profiling data in systems modeling to support quantitative risk assessments, and in developing complementary higher throughput exposure models. This integrated approach will enable analysis of life-stage susceptibility, and understanding of the exposures, pathways, and key events by which chemicals exert their toxicity in developing systems (e.g., endocrine-related pathways). The CTRP will be a critical component in next-generation risk assessments utilizing quantitative high-throughput data and providing a much higher capacity for assessing chemical toxicity than is currently available.

The role of social and built environments in predicting self-rated stress: A multilevel analysis in Philadelphia

Most studies of the predictors of stress focus on individual characteristics. Linking multiple contextual data sources to an individual-level health survey, we explore the associations of both built and social environment determinants with self-rated stress. At the individual level few social factors were significant predictors, although neighborhood trust and food insecurity have independent effects on stress. At the neighborhood level, the presence of hazardous waste sites and traffic volume were determinants of self-rated stress even after controlling for other individual characteristics. The latter two factors are of relevance to public health policy as they are potentially modifiable.

Hidden agendas: How dubious motives can lurk behind environmental issues—and complicate public dialogue

© 2010 Wiley Periodicals, Inc. Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/tqem.20250 Professionals in the field of community relations/public involvement need to identify both the stakeholders who may wish to “weigh in” on environmental issues and those stakeholders’ needs, wants, and opinions. Whether the issue involves a permitting action, the investigation or cleanup of a hazardous waste site, or ongoing operations at a manufacturing facility, if there is public concern or opposition, the source will most often be:

Superfund: is it safe to go home?

The Superfund law does not effectively address exposure of the residents surrounding a hazardous waste site before, during, and after cleanup.

Ground Gas Handbook

Emissions of toxic gases are expected to be encountered in a variety of geologic settings, for example: (1) engineered waste disposal sites, which are nominally required to incorporate design measures for capture and control; (2) all manner of dumps and other un-engineered and/or uncontrolled waste disposal sites; (3) derelict industrial sites and their plant and off-plant dump and discharge points; and (4) certain natural bodies, in particular, shallow oil fields, or deposits of toxic mineral compounds formed and/or released during the geologic history of the site. Geologists, therefore, are the natural choice for the professional needed to predict and discover these ground gas situations worthy of constant environmental consideration. These gases emanate as volatile releases from toxic compounds, natural or man-made, under conditions of vapor-pressure release (i.e., volatilization) and are subject to release under changing geochemical conditions, most often due to contact with perched or vadose groundwater. Some of these releases occur along geologic pathways of transport, while others constitute near-direct transmission into various “confined spaces” frequented by unsuspecting human receptors. What the Book Offers Considering the over-riding geologic parameters related to generation and release of toxic gases, this book can be useful, in a practical sense, for geoscience professionals involved in all aspects of waste-management facility design, construction, and compliance, and/or in the remediation of uncontrolled hazardous waste sites. The content of the book will not tax the reader's capacity to understand or to act upon the contents; the reader will merely need to discover how to integrate their own “needs.” The professional backgrounds of the …

Concentrations of selected organochlorines and chlorobenzenes in the serum of former Love Canal residents, Niagara Falls, New York ,☆,☆☆☆This study was approved by the New York State Department of Health Institutional Review Board as part of the larger Love Canal Follow-up Health Study (study #99-312) at a full board meeting in August 1996 and annually thereafter.

Love Canal, in Niagara Falls, NY is among the earliest and most significant hazardous waste sites in the USA, but no study has ever measured chemical body burdens in nearby residents to document that human exposure occurred. This study measured concentrations of selected organochlorines and chlorinated benzenes in archived serum samples collected from former Love Canal residents. We analyzed serum samples collected from 373 former residents in 1978-1979 for compounds disposed of at Love Canal, and we compared their concentrations according to surrogate indicators of exposure such as residential proximity, adjusting for potential confounders. Three compounds were detectable in the serum of most participants: 1,2,4-trichlorobenzene (1,2,4-TCB), beta-hexachlorocyclohexane (beta-HCH) and 1,2-dichlorobenzene (1,2-DCB). Concentrations of 1,2,4-TCB and 1,2-DCB were 2-14 times greater among persons who at the time their blood was collected lived closest to the Canal compared to those living further away. We found no consistent trends for beta-HCH with respect to any exposure definition. These results provide evidence that residential proximity to Love Canal contributed to the body burden of certain contaminants, and helps validate the use of surrogate exposure measures in health effect studies. Further surveillance of the Love Canal cohort is warranted.

Impact of iron sulfide transformation on trichloroethylene degradation

Trichloroethylene (TCE) is one of the most common and persistent groundwater contaminants encountered at hazardous waste sites around the world. A growing body of evidence indicates that iron sulfides play an important role in degrading TCE in natural environments and in engineered systems designed for groundwater cleanup. In this study, we investigate transformation processes of iron sulfides and consequent impacts on TCE degradation using batch experimental techniques, transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray absorption spectroscopy (XAS). Our results show that mackinawite is highly reactive toward TCE and no detectable mineralogical changes were detected during the course of reaction. However, freeze-dried FeS transformed to a mixture of mackinawite and greigite during the freeze drying process, with further mineralogical changes during reaction with TCE to lepidocrocite, goethite and pyrite. Newly formed lepidocrocite is a transient phase, with conversion to goethite over time. TCE transformation kinetics show that freeze-dried FeS is 20–50 times less reactive in degrading TCE than non-freeze-dried FeS, and the TCE degradation rate increases with pH (from 5.4 to 8.3), possibly due to an increase of surface deprotonation or electron transfer at higher pH. Results suggest that freeze drying could cause FeS particle aggregation, decreased surface area and availability of reactive sites; it also could change FeS mineralogy and accelerate mineral transformation. These aspects could contribute to the lower reactivity of freeze-dried FeS toward TCE degradation. Modeling results show that FeS transformation in natural environments depends on specific biogeochemical conditions, and natural FeS transformation may affect mineral reactivity in a similar way as compared to the freeze drying process. Rapid transformation of FeS to FeS 2 could significantly slow down TCE degradation in both natural and engineered systems.

Inequalities, inequities, environmental justice in waste management and health

The scientific evidence on the health effects of waste-related exposure is not conclusive. Differential exposure to waste by socio-economic status (SES) is often documented, but the interplay between environmental and social factors, crucial for policy making, is not well known. This review aims at investigating the role of health inequalities and inequities in waste management. Grey and peer-reviewed literature, published after 1983, was reviewed from Europe and the USA. Available data provide consistent indications that waste facilities are often disproportionally more located in areas with more deprived residents, or from ethnical minorities. This applies to waste incinerators, landfills, hazardous waste sites, legal and illegal. In studies considering health effects (mainly from Europe), risks are estimated with standardization for SES. Such standardization almost always decreases risk estimates for several cancers and reproductive outcomes. However, effect modification is not investigated in these studies. The patterns of association between waste-related environmental pressures and SES suggest that some of the observed inequalities in exposure and health represent a case of environmental injustice as they are the result of social processes and may be prevented, at least partly. Disentangling the possible health effects remains difficult, due to limitations in the methodology. It seems important to investigate if disadvantaged people are more vulnerable, i.e. risks differ in different social groups living in the same area. Notwithstanding these open questions, public health officers and decision makers should identify waste management policies to minimize their potential health impacts and their unequal distribution.

An estimation of the health impact of groundwater pollution caused by dumping of chlorinated solvents

Background Hazardous waste sites are major environmental concerns, but few studies have quantified their expected utility loss on health. Objectives To evaluate the health impact of groundwater pollution by an electronics manufacturing factory, we conducted a health risk assessment based on expected utility loss from liver cancer. Methods Based on measurements of major pollutants, we estimated the likelihood of developing liver cancer after exposure to groundwater contamination. All patients with liver cancer between 1990 and 2005 in the Taiwan Cancer Registry were followed through 2007 using the National Mortality Registry to obtain survival function. Quality of life was assessed with two cross-sectional surveys, one employing the standard gamble method, and the other using the EQ-5D instrument. Quality-adjusted life expectancy (QALE) was estimated by multiplying the utility values with survival function under the unit of quality-adjusted life year (QALY). The difference of QALE between the cancer cohort and the age- and gender-matched reference population was calculated to represent the utility loss due to liver cancer. Results A total of 94,144 patients with liver cancer were identified. The average utility loss to development of liver cancer was 17.5 QALYs. Based on toxicological approach, we estimated that groundwater pollution caused 1.7 extra cases of liver cancer, with an overall loss of 29.8 QALYs. Based on epidemiological approach, the expected annual excess number of liver cancer would be 3.65, which would have been accumulated through the years, had the pollution not mitigated. Conclusions We demonstrated a practical approach for comparative health risk assessment using QALY as the common unit. This approach can be used for policy decisions based on possible health risks.

Photobiodegradation of halogenated aromatic pollutants

Release of wide range of compounds as a consequence of industrial development is now a serious environmental problem. Numerous hazardous waste sites have been generated worldwide resulting from the accumulation of xenobiotics in soil and water. Aromatic compounds constitute a large and diverse group of chemicals that are responsible for causing widespread environmental pollution. Among them halogenated aromatic hydrocarbons are very stable to undergo degradation due to resonance energy and inertness of carbon-halogen, carbon-hydrogen and carbon-carbon covalent bonds. The physico-chemical remedial strategies to clean up sites contaminated by these compounds are inadequate and economically inefficient. Therefore, research is increasingly being focused on development of biological approaches for their remediation. The hunt for the microorganisms degrading halogenated aromatic pollutants has been successful in discovering a diverse range of aerobic, anaerobic and phototrophic bacteria. The bacteria mineralize the toxic halogenated pollutants into harmless products thereby contributing towards conservation of the environment quality.

A high-resolution aeromagnetic field test in Friuli: towards developing remote location of buried ferro-metallic bodies

High Resolution AeroMagnetic surveys (HRAM) are a novel tool experimented in several countries for volcano and earthquake hazard re-assessment, ground water exploration and mitigation, hazardous waste site characterization and accurate location of buried ferrous objects (drums, UXO, pipelines). The improvements achieved by HRAM stem from lower terrain clearance coupled with accurately positioned, real-time differential navigation on closely spaced flight grids. In field cultural noise filtering, advanced data processing, imaging and improved interpretation techniques enhance data information content. Development of HRAM approaches might also contribute to mitigate environmental hazards present throughout the Italian territory. Hence an HRAM field test was performed in July 2000 in Friuli, North-Eastern Italy to assess the capabilities and limitations of HRAM over a buried pipeline and a domestic waste site. A Cesium magnetometer in towed bird configuration was used on two separate grids. Profile line spacing was 50-100 m and bird nominal ground clearance was set to 50 m. Microlevelled total field magnetic anomaly data forms the basis for subsequent advanced processing products including 3D analytic signal, maximum horizontal gradient of pseudo-gravity and 3D Euler Deconvolution. The magnetic signatures we detected and enhanced over the environmental test site area in Friuli are also compared with similar but more extensive HRAM signatures recently observed in other countries.

Carboxymethyl-β-cyclodextrin mitigates toxicity of cadmium, cobalt, and copper during naphthalene biodegradation

Hazardous waste sites are commonly contaminated with both organic and metal pollutants. Many metal pollutants have been shown to inhibit organic pollutant biodegradation. We investigated the ability of a modified, polydentate cyclodextrin (carboxymethyl-beta-cyclodextrin, CMCD) to reduce the toxicity of 33.4 microM cadmium, cobalt or copper during naphthalene degradation by a Burkholderia sp. in 120 h aerobic, batch studies. The highest investigated concentration of CMCD, 3340 microM, reduced cadmium, cobalt, and copper toxicity. With each metal, the length of the lag phase was reduced (by as much as 108 h with cobalt or copper), the cell yield was increased (by as much as a factor of 16 with cobalt), and the growth rate was increased (by as much as a factor of 31 with cobalt). The degrader was unable to use CMCD as the sole source of carbon and energy. Our data suggest that the ability of CMCD to complex metals plays an important role in its ability to mitigate metal toxicity and that CMCD has the potential to enhance biodegradation in organic and metal co-contaminated environments.

Hit or Miss?: Benefits and Risks of Using Nanoparticles for in Situ Remediation

Nanotechnology holds the promise of vastly expanding our ability to clean up hazardous waste sites and decontaminate polluted ground-water in situ. Polychlorinated biphenyls, organic solvents, petroleum products, arsenic, and many more contaminants are on the list that specifically engineered nanoparticles could rapidly remove from contaminated soil and water, saving billions of dollars that would have been spent on more expensive conventional remediation methods. These possibilitites are discussed in a review of field tests using nano-materials [EHP 117:1823–1831; Karn et al.]. However, the authors caution, our knowledge of the potential environmental and health hazards posed by these nanomaterials is in its infancy. In the United States alone there are hundreds of thousands of sites contaminated with hazardous wastes, with more than 1,200 requiring priority attention. Using traditional remediation technologies, such as pumping out and treating contaminated groundwater and removing contaminated soil, the job of cleaning up U.S. hazardous waste sites could take 35 years and $250 billion. The authors of this review, however, report on results showing that nanoscale zero-valent iron (nZVI) nanoparticles could dramatically reduce the time required to remediate soil and water as well as, according to one report, save 80–90% compared with conventional methods. Although tiny in diameter, the surface area of these iron-based nanoparticles reaches 20–40 m2/g. This relatively large surface area can greatly increase the particles’ reactivity. Flowing with the groundwater they can spread out to react with pollutants, transforming them into safer compounds, including compounds that bacteria can break down. The authors provide many examples of how nZVIs, currently the nanomaterials most widely used for in situ remediation, produced measurable effects within days or, in some cases, hours. However, the authors also emphasize that we do not know much about the potential adverse effects of nano-particles deployed into the environment—agents that could, for example, end up in our drinking water. Some nanomaterials have already been found to enter organisms. Might some be toxic or transport bound pollutants to places they might not otherwise have gone? Can they be biomagnified? How do they affect living organisms? The authors point out that, although the environment is full of naturally occurring nanoparticles, manufactured nanoparticles may behave in unpredictable ways. They recommend that while we improve engineering applications using nanoparticles for in situ remediation, we also develop the analytical tools to enable the study of manufactured nanoparticles in the environment and increase research on the ecosystem effects of these materials.