Novel gas exposure system for the controlled exposure of plants to gaseous hydrogen fluoride.

Plants can serve as sensitive bioindicators of the presence of contaminant vapors in the atmosphere. This work describes a novel laboratory-based gas exposure system capable of calibrating plants as bioindicators for the detection and delineation of the atmospheric contaminant hydrogen fluoride (HF) as a preparatory step for monitoring release emissions. To evaluate changes in plant phenotype and stress-induced physiological effects attributed to HF alone, the gas exposure chamber must have additional controls to simulate otherwise optimal plant growth conditions including variables such as light intensity, photoperiod, temperature, and irrigation. The exposure system was designed to maintain constant growth conditions during a series of independent experiments that varied between optimal (control) and stressful (HF exposure) conditions. The system was also designed to ensure the safe handling and application of HF. An initial system calibration introduced HF gas into the exposure chamber and monitored HF concentrations by cavity ring-down spectroscopy for a 48-h period. Stable concentrations inside the exposure chamber were observed after approximately 15 h, and losses of HF to the system ranged from 88 to 91%. A model plant species (Festuca arundinacea) was then exposed to HF for 48 h. Visual phenotype stress-induced responses aligned with symptoms reported in the literature for fluoride exposure (tip dieback and discoloration along the dieback transition margin). Fluoride concentrations in exposed tissues compared to control tissues confirmed enhanced fluoride uptake due to HF exposure. The system described herein can be applied to other reactive atmospheric pollutants of interest in support of bioindicator research.

Quarantine and serial testing for variants of SARS-CoV-2 with benefits of vaccination and boosting on consequent control of COVID-19.

Quarantine and serial testing strategies for a disease depend principally on its incubation period and infectiousness profile. In the context of COVID-19, these primary public health tools must be modulated with successive SARS CoV-2 variants of concern that dominate transmission. Our analysis shows that (1) vaccination status of an individual makes little difference to the determination of the appropriate quarantine duration of an infected case, whereas vaccination coverage of the population can have a substantial effect on this duration, (2) successive variants can challenge disease control efforts by their earlier and increased transmission in the disease time course relative to prior variants, and (3) sufficient vaccine boosting of a population substantially aids the suppression of local transmission through frequent serial testing. For instance, with Omicron, increasing immunity through vaccination and boosters-for instance with 100% of the population is fully immunized and at least 24% having received a third dose-can reduce quarantine durations by up to 2 d, as well as substantially aid in the repression of outbreaks through serial testing. Our analysis highlights the paramount importance of maintaining high population immunity, preferably by booster uptake, and the role of quarantine and testing to control the spread of SARS CoV-2.

Comparative analyses of eighteen rapid antigen tests and RT-PCR for COVID-19 quarantine and surveillance-based isolation.

Background: Rapid antigen (RA) tests are being increasingly employed to detect SARS-CoV-2 infections in quarantine and surveillance. Prior research has focused on RT-PCR testing, a single RA test, or generic diagnostic characteristics of RA tests in assessing testing strategies. Methods: We have conducted a comparative analysis of the post-quarantine transmission, the effective reproduction number during serial testing, and the false-positive rates for 18 RA tests with emergency use authorization from The United States Food and Drug Administration and an RT-PCR test. To quantify the extent of transmission, we developed an analytical mathematical framework informed by COVID-19 infectiousness, test specificity, and temporal diagnostic sensitivity data. Results: We demonstrate that the relative effectiveness of RA tests and RT-PCR testing in reducing post-quarantine transmission depends on the quarantine duration and the turnaround time of testing results. For quarantines of two days or shorter, conducting a RA test on exit from quarantine reduces onward transmission more than a single RT-PCR test (with a 24-h delay) conducted upon exit. Applied to a complementary approach of performing serial testing at a specified frequency paired with isolation of positives, we have shown that RA tests outperform RT-PCR with a 24-h delay. The results from our modeling framework are consistent with quarantine and serial testing data collected from a remote industry setting. Conclusions: These RA test-specific results are an important component of the tool set for policy decision-making, and demonstrate that judicious selection of an appropriate RA test can supply a viable alternative to RT-PCR in efforts to control the spread of disease.

Previous research on SARS-CoV-2 infection has determined optimal timing for testing in quarantine and the utility of different frequencies of testing for infection surveillance using RT-PCR and generalized rapid antigen tests. However, these strategies can depend on the specific rapid antigen test used. By examining 18 rapid antigen tests, we demonstrate that a single rapid antigen test performs better than RT-PCR when quarantines are two days or less in duration. In the context of infection surveillance, the ability of a rapid antigen test to provide results quickly counteracts its lower sensitivity with potentially more false positives. Our findings indicate that rapid antigen tests can be a suitable alternative to RT-PCR for application in quarantine and infection surveillance.

Environmental assessment of pediatric Lead exposure in Tehran; a prospective cross-sectional study.

BACKGROUND: Ingestion and inhalation are common routes of exposure for lead in humans. Developing countries still have unacceptably high rates of lead toxicity, especially in children. Studies on probable risk factors of lead poisoning in Iranian children are insufficient. In this study, we aimed to evaluate possible environmental factors in children with high blood lead concentrations living in Tehran and neighboring cities. METHODS: In a prospective cross-sectional study between March 2018 and March 2019 we followed all children referred from two pediatric gastrointestinal clinics with blood lead level (BLL) > 5 µg/dL in metropolitan Tehran to investigate possible environmental risk factors in their home. Household specimens including scratched wall paint, house floor dust, windowsill dust, tap water, and consumed spice were evaluated using atomic absorption method to detect lead concentrations. Epidemiological and environmental data collected through in-depth interviews with parents/guardians. Industrial areas were defined based on municipality maps on industrial places. RESULTS: Thirty of 56 parents/guardians with BLL > 5 µg/dL agreed to be followed through environmental investigation. The only categorical statistically significant risk factor was a history of lead poisoning in the family and living in an industrial zone. There was a positive correlation between BLL and interior windowsills dust lead level, r = 0.46, p = 0.01. Scratched paint lead level and BLL showed a significant positive correlation, r = 0.50, p = 0.005. House floor dust lead level (median = 77.4, p < 0.001) and interior windowsill dust lead level (median = 291, p = 0.011) were both significantly higher than the environmental protection agency (EPA) standards of 40 µg/ft2, 250 µg/ft2. Interior windowsill dust lead concentrations were significantly higher in industrial areas (p = 0.026). CONCLUSION: Children's playing environment should be cleaned more often to reduce dust. Moreover, specific rules may need to be implemented for paint lead concentrations and air pollution, especially in industrial areas.

Optimal COVID-19 quarantine and testing strategies.

For COVID-19, it is vital to understand if quarantines shorter than 14 days can be equally effective with judiciously deployed testing. Here, we develop a mathematical model that quantifies the probability of post-quarantine transmission incorporating testing into travel quarantine, quarantine of traced contacts with an unknown time of infection, and quarantine of cases with a known time of exposure. We find that testing on exit (or entry and exit) can reduce the duration of a 14-day quarantine by 50%, while testing on entry shortens quarantine by at most one day. In a real-world test of our theory applied to offshore oil rig employees, 47 positives were obtained with testing on entry and exit to quarantine, of which 16 had tested negative at entry; preventing an expected nine offshore transmission events that each could have led to outbreaks. We show that appropriately timed testing can make shorter quarantines effective.

Optimal COVID-19 quarantine and testing strategies.

As economic woes of the COVID-19 pandemic deepen, strategies are being formulated to avoid the need for prolonged stay-at-home orders, while implementing risk-based quarantine, testing, contact tracing and surveillance protocols. Given limited resources and the significant economic, public health, and operational challenges of the current 14-day quarantine recommendation, it is vital to understand if shorter but equally effective quarantine and testing strategies can be deployed. To quantify the probability of post-quarantine transmission upon isolation of a positive test, we developed a mathematical model in which we varied quarantine duration and the timing of molecular tests for three scenarios of entry into quarantine. Specifically, we consider travel quarantine, quarantine of traced contacts with an unknown time if infection, and quarantine of cases with a known time of exposure. With a one-day delay between test and result, we found that testing on exit (or entry and exit) can reduce the duration of a 14-day quarantine by 50%, while testing on entry shortened quarantine by at most one day. Testing on exit more effectively reduces post-quarantine transmission than testing upon entry. Furthermore, we identified the optimal testing date within quarantines of varying duration, finding that testing on exit was most effective for quarantines lasting up to seven days. As a real-world validation of these principles, we analyzed the results of 4,040 SARS CoV-2 RT-PCR tests administered to offshore oil rig employees. Among the 47 positives obtained with a testing on entry and exit strategy, 16 cases that previously tested negative at entry were identified, with no further cases detected among employees following quarantine exit. Moreover, this strategy successfully prevented an expected nine offshore transmission events stemming from cases who had tested negative on the entry test, each one a serious concern for initiating rapid spread and a disabling outbreak in the close quarters of an offshore rig. This successful outcome highlights that appropriately timed testing can make shorter quarantines more effective, thereby minimizing economic impacts, disruptions to operational integrity, and COVID-related public health risks.

Examples of coupled human and environmental systems from the extractive industry and hydropower sector interfaces.

Large-scale corporate projects, particularly those in extractive industries or hydropower development, have a history from early in the twentieth century of creating negative environmental, social, and health impacts on communities proximal to their operations. In many instances, especially for hydropower projects, the forced resettlement of entire communities was a feature in which local cultures and core human rights were severely impacted. These projects triggered an activist opposition that progressively expanded and became influential at both the host community level and with multilateral financial institutions. In parallel to, and spurred by, this activism, a shift occurred in 1969 with the passage of the National Environmental Policy Act in the United States, which required Environmental Impact Assessment (EIA) for certain types of industrial and infrastructure projects. Over the last four decades, there has been a global movement to develop a formal legal/regulatory EIA process for large industrial and infrastructure projects. In addition, social, health, and human rights impact assessments, with associated mitigation plans, were sequentially initiated and have increasingly influenced project design and relations among companies, host governments, and locally impacted communities. Often, beneficial community-level social, economic, and health programs have voluntarily been put in place by companies. These flagship programs can serve as benchmarks for community-corporate-government partnerships in the future. Here, we present examples of such positive phenomena and also focus attention on a myriad of challenges that still lie ahead.

Experience and lessons from health impact assessment for human rights impact assessment.

As globalisation has opened remote parts of the world to foreign investment, global leaders at the United Nations and beyond have called on multinational companies to foresee and mitigate negative impacts on the communities surrounding their overseas operations. This movement towards corporate impact assessment began with a push for environmental and social inquiries. It has been followed by demands for more detailed assessments, including health and human rights. In the policy world the two have been joined as a right-to-health impact assessment. In the corporate world, the right-to-health approach fulfils neither managers' need to comprehensively understand impacts of a project, nor rightsholders' need to know that the full suite of their human rights will be safe from violation. Despite the limitations of a right-to-health tool for companies, integration of health into human rights provides numerous potential benefits to companies and the communities they affect. Here, a detailed health analysis through the human rights lens is carried out, drawing on a case study from the United Republic of Tanzania. This paper examines the positive and negative health and human rights impacts of a corporate operation in a low-income setting, as viewed through the human rights lens, considering observations on the added value of the approach. It explores the relationship between health impact assessment (HIA) and human rights impact assessment (HRIA). First, it considers the ways in which HIA, as a study directly concerned with human welfare, is a more appropriate guide than environmental or social impact assessment for evaluating human rights impacts. Second, it considers the contributions HRIA can make to HIA, by viewing determinants of health not as direct versus indirect, but as interrelated.

Baseline malaria vector transmission dynamics in communities in Ahafo mining area in Ghana.

BACKGROUND: Malaria vector dynamics are relevant prior to commencement of mining activities. A baseline entomology survey was conducted in Asutifi and Tano (referred to as Ahafo) in the Brong-Ahafo geo-political region of Ghana during preparatory stages for mining by Newmont Ghana Gold Limited. METHODS: Between November 2006 and August 2007, eight Centre for Disease Control light traps were set daily (Monday-Friday) to collect mosquitoes. Traps were hanged in rooms that were selected from a pool of 1,100 randomly selected houses. Types of materials used in construction of houses were recorded and mosquito prevention measures were assessed from occupants. RESULTS: A total of 5,393 mosquitoes were caught that comprised Anopheles gambiae (64.8%), Anopheles funestus (4.2%), as well as Culicines, comprising of Culex (30.4%) and Aedes species (0.6%). The entomological inoculation rate in Asutifi (279 infective bites/person/month) and Tano (487 infective bites/person/month) demonstrate relatively high malaria transmission in Ahafo. The presence or absence of Anopheles vectors in rooms was influenced by the type of roofing material (OR 2.33, 95%CI: 1.29-4.22, p = 0.01) as well as the presence of eaves gaps (OR 1.80, 95%CI: 1.37-2.37, p < 0.01). It was also associated with bed net availability in the room (OR 1.39, 95%CI: 1.08-1.80, p = 0.01). Over 80% of the houses were roofed with corrugated zinc sheets. Over 60% of the houses in Ahafo had no eaves gaps to give access to mosquito entry and exit into rooms and mosquito bed net coverage was over 50%. Other measures used in preventing mosquito bites included; coil (22.1%), insecticide spray (9.4%), repellent cream (4.0%) and smoky fires (1.1%), contributed minimally to individual mosquito preventive measures in impact areas. Similarly, levels of protection; coil (16.9%), insecticide spray (2.8%) and repellent cream (0.3%) for the non-impact areas, depict low individual prevention measures. CONCLUSIONS: The survey identified areas where intensified vector control activities would be beneficial. It also demonstrates that transmission in Asutifi and Tano is high even before the commencement of mining operations. This study serves as baseline information to assess impact of mining activities in relation to future vector control interventions.

Multinational corporations and infectious disease: Embracing human rights management techniques.

BACKGROUND: Global health institutions have called for governments, international organisations and health practitioners to employ a human rights-based approach to infectious diseases. The motivation for a human rights approach is clear: poverty and inequality create conditions for infectious diseases to thrive, and the diseases, in turn, interact with social-ecological systems to promulgate poverty, inequity and indignity. Governments and intergovernmental organisations should be concerned with the control and elimination of these diseases, as widespread infections delay economic growth and contribute to higher healthcare costs and slower processes for realising universal human rights. These social determinants and economic outcomes associated with infectious diseases should interest multinational companies, partly because they have bearing on corporate productivity and, increasingly, because new global norms impose on companies a responsibility to respect human rights, including the right to health. METHODS: We reviewed historical and recent developments at the interface of infectious diseases, human rights and multinational corporations. Our investigation was supplemented with field-level insights at corporate capital projects that were developed in areas of high endemicity of infectious diseases, which embraced rights-based disease control strategies. RESULTS: Experience and literature provide a longstanding business case and an emerging social responsibility case for corporations to apply a human rights approach to health programmes at global operations. Indeed, in an increasingly globalised and interconnected world, multinational corporations have an interest, and an important role to play, in advancing rights-based control strategies for infectious diseases. CONCLUSIONS: There are new opportunities for governments and international health agencies to enlist corporate business actors in disease control and elimination strategies. Guidance offered by the United Nations in 2011 that is widely embraced by companies, governments and civil society provides a roadmap for engaging business enterprises in rights-based disease management strategies to mitigate disease transmission rates and improve human welfare outcomes.

The State of Alaska's early experience with institutionalization of health impact assessment.

BACKGROUND: Many nations routinely include health impact assessments (HIA) in public policy decisions. Institutionalization of HIA formally integrates health considerations into a governmental decision-making process. We describe an example of institutionalization in the United States through Alaska's early experience with institutionalization of HIA. LITERATURE REVIEW: HIA arose from a series of health conferences in the 1970s that affirmed the importance of "health for all." A number of key milestones eventually defined HIA as a unique field of impact assessment. There are several approaches to institutionalization, and one common approach in the United States is through the National Environmental Policy Act (NEPA). NEPA formed the basis for the earliest HIAs in Alaska. PROGRAM DESCRIPTION: Early HIAs in Alaska led to conferences, working groups, a state guidance document and the institutionalization of a HIA program within the Department of Health and Social Services in 2010. A medical epidemiologist staffs the program, which utilizes contractors to meet rising demand for HIA. The HIA program has sustainable funding from the state budget and from the state's natural resource permitting process. The HIA document is the main deliverable, but the program performs other tasks, including fieldwork and technical reviews. The HIA program works closely with a host of collaborative partners. CONCLUSION: Alaska's institutionalized HIA program benefits from sustainable funding that promotes continuous quality improvement and involves the program in the entire life cycle of a development project. The program structure adapts well to variations in workflow and supports a host of quality control activities. Currently, the program focuses on HIAs for natural resource development projects.

Untapped potential of health impact assessment.

The World Health Organization has promoted health impact assessment (HIA) for over 20 years. At the 2012 United Nations Conference on Sustainable Development (Rio+20), HIA was discussed as a critical method for linking health to "green economy" and "institutional framework" strategies for sustainable development. In countries having a high human development index (HDI), HIA has been added to the overall assessment suite that typically includes potential environmental and social impacts, but it is rarely required as part of the environmental and social impact assessment for large development projects. When they are performed, project-driven HIAs are governed by a combination of project proponent and multilateral lender performance standards rather than host country requirements. Not surprisingly, in low-HDI countries HIA is missing from the programme and policy arena in the absence of an external project driver. Major drivers of global change (e.g. population growth and urbanization, growing pressure on natural resources and climate change) inordinately affect low- and medium-HDI countries; however, in such countries HIA is conspicuously absent. If the cloak of HIA invisibility is to be removed, it must be shown that HIA is useful and beneficial and, hence, an essential component of the 21st century's sustainable development agenda. We analyse where and how HIA can become fully integrated into the impact assessment suite and argue that the impact of HIA must not remain obscure.

L'Organisation mondiale de la Santé encourage l'évaluation de l'impact sanitaire (EIS) depuis plus de 20 ans. Lors de la Conférence des Nations Unies de 2012 sur le développement durable (Rio+20), l'EIS a été discutée comme une méthode essentielle pour lier la santé à «l'économie verte¼ et aux stratégies du «cadre institutionnel¼ pour le développement durable. Dans les pays présentant un indice de développement humain élevé (IDH), l'EIS a été ajoutée à la suite de l'évaluation globale qui inclut généralement les impacts environnementaux et sociaux, mais qui est rarement nécessaire dans le cadre de l'évaluation de l'impact environnemental et social des grands projets de développement. Quand elles sont effectuées, les EIS axées sur les projets sont régies par une combinaison de normes de performances multilatérales du prêteur et du promoteur du projet, plutôt que par les exigences du pays d'accueil. Il n'est pas surprenant de constater que, dans les pays à faible IDH, l'EIS ne fait pas partie du programme et de la scène politique en l'absence d'un pilote externe du projet. Les principaux facteurs du changement mondial (comme la croissance démographique et l'urbanisation, la pression croissante sur les ressources naturelles et le changement climatique) affectent démesurément les pays à faible et à moyen IDH. Toutefois, dans ces pays, l'EIS est ostensiblement absente. Si la cape d'invisibilité de l'EIS doit être retirée, on doit prouver que l'EIS est utile et bénéfique, et que c'est donc une composante essentielle du programme du XXIe siècle en matière de développement durable. Nous analysons où et comment l'EIS peut être pleinement intégrée dans la suite de l'évaluation de l'impact et soutenons que l'impact de l'EIS ne doit pas rester dans l'ombre.

La Organización Mundial de la Salud ha promovido la evaluación del impacto sanitario (EIS) a lo largo de más de 20 años. En la Conferencia de las Naciones Unidas sobre el Desarrollo Sostenible (Río+20) celebrada en el año 2012, se debatió sobre la EIS como método fundamental para vincular la salud con estrategias para promover una «economía ecológica¼ y un «marco institucional¼ para el desarrollo sostenible. En los países con un índice de desarrollo humano (IDH) elevado, la EIS se ha agregado a la evaluación global que normalmente incluye los impactos medioambientales y sociales, pero raramente se requiere como parte de la evaluación del impacto medioambiental y social de proyectos de desarrollo de grandes dimensiones. Cuando estos se llevan a cabo, las EIS impulsadas por proyectos se rigen más por una combinación de los estándares del defensor del proyecto y la función multilateral del prestamista que por los requerimientos del país anfitrión. No sorprende que, en países con un IDH bajo, la EIS no se incluya en los programas y en las estrategias debido a la ausencia de un conductor externo de los proyectos. Los principales factores del cambio global (por ejemplo, el crecimiento demográfico y la urbanización, la creciente presión sobre los recursos naturales y el cambio climático) afectan excesivamente a los países con IDH bajos y medios; sin embargo, en esos países la EIS brilla por su ausencia. Si se desea eliminar la capa de invisibilidad de la EIS, es necesario demostrar que esta última es útil y beneficiosa y, por tanto, un punto esencial de la agenda para el desarrollo sostenible del siglo XXI. Analizamos dónde y cómo podría integrarse plenamente la EIS dentro de las evaluaciones de impactos y opinamos que el impacto de la EIS no debe permanecer oculto.

Health impact assessment of industrial development projects: a spatio-temporal visualization.

Development and implementation of large-scale industrial projects in complex eco-epidemiological settings typically require combined environmental, social and health impact assessments. We present a generic, spatio-temporal health impact assessment (HIA) visualization, which can be readily adapted to specific projects and key stakeholders, including poorly literate communities that might be affected by consequences of a project. We illustrate how the occurrence of a variety of complex events can be utilized for stakeholder communication, awareness creation, interactive learning as well as formulating HIA research and implementation questions. Methodological features are highlighted in the context of an iron ore development in a rural part of Africa.

Enhancing impact: visualization of an integrated impact assessment strategy.

The environmental impact assessment process is over 40 years old and has dramatically expanded. Topics, such as social, health and human rights impact are now included. The main body of an impact analysis is generally hundreds of pages long and supported by countless technical appendices. For large, oil/gas, mining and water resources projects both the volume and technical sophistication of the reports has far exceeded the processing ability of host communities. Instead of informing and empowering, the reports are abstruse and overwhelming. Reinvention is required. The development of a visual integrated impact assessment strategy that utilizes remote sensing and spatial analyses is described.

Malaria epidemiology in the Ahafo area of Ghana.

BACKGROUND: Plasmodium falciparum malaria remains endemic in sub-Saharan Africa including Ghana. The epidemiology of malaria in special areas, such as mining areas needs to be monitored and controlled. Newmont Ghana Gold Limited is conducting mining activities in the Brong Ahafo Region of Ghana that may have an impact on the diseases such as malaria in the mining area. METHODS: Prior to the start of mining activities, a cross-sectional survey was conducted in 2006/2007 to determine malaria epidemiology, including malaria parasitaemia and anaemia among children < 5 years and monthly malaria transmission in a mining area of Ghana. RESULTS: A total of 1,671 households with a child less than five years were selected. About 50% of the household heads were males. The prevalence of any malaria parasitaemia was 22.8% (95% CI 20.8-24.9). Plasmodium falciparum represented 98.1% (95% CI 96.2-99.2) of parasitaemia. The geometric mean P. falciparum asexual parasite count was 1,602 (95% CI 1,140-2,252) and 1,195 (95% CI 985-1,449) among children < 24 months and ≥ 24 months respectively. Health insurance membership (OR 0.60, 95% CI 0.45-0.80, p = 0.001) and the least poor (OR 0.57, 95% CI 0.37-0.90, p = 0.001) were protected against malaria parasitaemia. The prevalence of anaemia was high among children < 24 months compared to children ≥ 24 months (44.1% (95% CI 40.0-48.3) and 23.8% (95% CI 21.2-26.5) respectively. About 69% (95% CI 66.3-70.9) of households own at least one ITN. The highest EIRs were record in May 2007 (669 ib/p/m) and June 2007 (826 ib/p/m). The EIR of Anopheles gambiae were generally higher than Anopheles funestus. CONCLUSION: The baseline malaria epidemiology suggests a high malaria transmission in the mining area prior to the start of mining activities. Efforts at controlling malaria in this mining area have been intensified but could be enhanced with increased resources and partnerships between the government and the private sector.

Baseline health situation of communities affected by the Nam Theun 2 hydroelectric project in central Lao PDR and indicators for monitoring.

Hydroelectric projects offer opportunities for infrastructure development and economic growth; yet, if not well designed, implemented and operated, they have the potential to negatively affect the health and well-being of local and distant downstream communities. Remote rural populations are particularly vulnerable to the sudden influx of men, materials and money, and associated population mixing that accompany project construction phases. Two large-scale baseline health surveys, carried out in 2001/2002 in two communities that were affected by the Nam Theun 2 hydroelectric project in central Lao PDR, were analysed. For the population to be resettled on the Nakai plateau it was observed that access to clean water and basic sanitation facilities was lacking. Faecal examinations revealed a high infection prevalence for Ascaris lumbricoides (67.7%), but relatively low prevalences for hookworm (9.7%), Taenia spp. (4.8%), Enterobius vermicularis (4.4%), Trichuris trichiura (3.9%), Strongyloides stercoralis (1.4%) and Opisthorchis viverrini (0.9%). For the population in the Xe Bang Fai downstream area, rapid diagnostic tests for malaria carried out in the rainy season found a prevalence below 1%, which might be explained by the complete coverage of households with insecticide-treated nets (99.8%). Anthropometric measurements in both populations suggest that wasting, stunting and underweight in under 5-year-old children were moderate to high; 15.9-17.5%, 40.4-55.7% and 35.8-55.7%, respectively. One out of six individuals aged above 14 years were malnourished, most likely as a result of early childhood wasting. Moderate anaemia, assessed by age- and sex-specific haemoglobin levels, was present in 43.8% (Nakai) and 54.9% of the individuals examined (Xe Bang Fai). Several indicators were extracted that can be utilised for monitoring changes in health, well-being and equity, as the project is implemented and operated.

Nanotechnology and nanotoxicology: a primer for clinicians.

Nanotechnology is the manipulation of matter in dimensions <100 nm. At this size, matter can take on different chemical and physical properties, giving the products characteristics useful to industry, medicine and technology. Government funding and private investors provide billions of research dollars for the development of new materials and applications. The potential utility of these technologies is such that they are expected be a trillion-dollar industry within the next 10 years. However, the novel properties of nanoengineered materials lead to the potential for different toxicity compared with the bulk material. The field of nanotoxicology is still in its infancy, however, with very limited literature regarding potential health effects. Inhalational toxicity is to be expected, given the known effects of inhaled fine particulate matter. However, the degree to which most nanoparticles will aerosolise remains to be determined. It has been proposed that dermal exposure will be the most relevant route of exposure, but there is considerably less literature regarding dermal effects and absorption. Less defined still are the potential effects of nanoproducts on fetal development and the environment.

Solvents and vapor intrusion pathways.

Vapor intrusion must be recognized appropriately as a separate pathway of contamination. Although many issues resemble those of other forms of contamination (particularly its entryway, which is similar to that of radon seepage), vapor intrusion stands apart as a unique risk requiring case-specific action. This article addresses these issues and the current understanding of the most appropriate and successful remedial actions.