The design of water markets when instream flows have value

The main objective of this paper is to design and test a decentralized exchange mechanism that generates the location-specific pricing necessary to achieve efficient allocations in the presence of instream flow values. Although a market-oriented approach has the potential to improve upon traditional command and control regulations, questions remain about how these rights-based institutions can be implemented such that the potential gains from liberalized trade can be realized. This article uses laboratory experiments to test three different water market institutions designed to incorporate instream flow values into the allocation mechanism through active participation of an environmental trader. The smart, computer-coordinated market described herein offers the potential to significantly reduce coordination problems and transaction costs associated with finding mutually beneficial trades that satisfy environmental constraints. We find that direct environmental participation in the market can achieve highly efficient and stable outcomes, although the potential does exist for the environmental agent to influence outcomes.     

Estimating historical landfill quantities to predict methane emissions

There are no observations for methane emissions from landfill waste in Ireland. Methane emissions are imputed from waste data. There are intermittent data on waste sent to landfill. We compare two alternative ways to impute the missing waste “data” and evaluate the impact on methane emissions. We estimate Irish historical landfill quantities from 1960–2008 and Irish methane emissions from 1968–2006. A model is constructed in which waste generation is a function of income, price of waste disposal and, household economies of scale. A transformation ratio of waste to methane is also included in the methane emissions model. Our results contrast significantly with the Irish Environmental Protection Agency’s (EPA) figures due to the differences in the underlying assumptions. The EPA’s waste generation and methane emission figures are larger than our estimates from the early 1990s onwards. Projections of the distance to target show that the EPA overestimates the required policy effort.     

Polychlorinated biphenyls and organochlorine pesticides in local waterbird eggs from Hong Kong: risk assessment to local waterbirds

The contamination status of the marine environment in Hong Kong was studied by measuring concentrations of organochlorine (OC) pollutants (i.e., hexachlorobenzene, aldrin, dieldrin, endrin, mirex, total heptachlor, total chlordane, total DDTs, total PCBs, and total toxaphenes) in the eggs of selected waterbird species from different locations around the city: Little Egret (Egretta garzetta) and Chinese Pond Heron (Ardeola bacchus) from Mai Po Village, Great Egret (Ardea alba) and Black-crowned Night Heron (Nycticorax nycticorax) from A Chau, and Chinese Pond Heron (A. bacchus) from Ho Sheung Heung. The mean concentrations of total PCBs and total DDTs ranged from 191-11 100 ng g⁻¹ lipid and 453-49 000 ng g⁻¹ lipid, respectively. Recent exposure of waterbirds to technical chlordane was found in Hong Kong. The risk characterization demonstrated potential risks to birds associated with exposure to DDE, which was found to cause a reduction in survival of young in Hong Kong Ardeids based on the endpoint in the risk assessment.     

Visibility impacts at Class I areas near the Bakken oil and gas development

Oil and gas activities have occurred in the Bakken region of North Dakota and nearby states and provinces since the 1950s but began increasing rapidly around 2008 due to new extraction methods. Three receptor-based techniques were used to examine the potential impacts of oil and gas extraction activities on airborne particulate concentrations in Class I areas in and around the Bakken. This work was based on long-term measurements from the Interagency Monitoring of Protected Visual Environments (IMPROVE) monitoring network. Spatial and temporal patterns in measured concentrations were examined before and after 2008 to better characterize the influence of these activities. A multisite back-trajectory analysis and a receptor-based source apportionment model were used to estimate impacts. Findings suggest that recent Bakken oil and gas activities have led to an increase in regional fine (PM_2.5—particles with aerodynamic diameters <2.5 µm) soil and elemental carbon (EC) concentrations, as well as coarse mass (CM = PM₁₀–PM_2.5). Influences on sulfate and nitrate concentrations were harder to discern due to the concurrent decline in regional emissions of precursors to these species from coal-fired electric generating stations. Impacts were largest at sites in North Dakota and Montana that are closest to the most recent drilling activity.

Implications: The increase in oil and gas activities in the Bakken region of North Dakota and surrounding areas has had a discernible impact on airborne particulate concentrations that impact visibility at protected sites in the region. However, the impact has been at least partially offset by a concurrent reduction in emissions from coal-fired electric generating stations. Continuing the recent reductions in flaring would likely be beneficial for the regional visual air quality.     

A Preliminary Look at Source-Receptor Relationships in the Texas-Mexico Border Area

ABSTRACT

Several factors have recently caused visibility impairment at Big Bend National Park, TX, to be of interest. Analyses of historical data collected there have shown that visibility is poorer and fine particle concentrations are higher at Big Bend than at other monitored Class I areas in the western United States. In addition, air masses frequently arrive there after crossing Mexico, where emissions are not well known. During September and October 1996, a field study was undertaken to begin examining the aerosol, visibility, and meteorology on both sides of the border. Results indicate that, during the study, the largest fractions of fine mass and light extinction at Big Bend were due to sulfates and the trace elements most closely associated with sulfate particles were Na and Se. Based on back trajectory modeling and the spatial, temporal, and inter-species relationships in the fine particle concentrations measured during the study, sulfates arrived at the park from both Mexico and the United States. Se was higher in Texas than in Northern Mexico, while V, Pb, Zn, Ni, and Mn were on average much higher in Mexico.     

Effects of 4-methylbenzylidene camphor (4-MBC) on neuronal and muscular development in zebrafish (<Emphasis Type="Italic">Danio rerio</Emphasis>) embryos

The negative effects of overexposure to ultraviolet (UV) radiation in humans, including sunburn and light-induced cellular injury, are of increasing public concern. 4-Methylbenzylidene camphor (4-MBC), an organic chemical UV filter, is an active ingredient in sunscreen products. To date, little information is available about its neurotoxicity during early vertebrate development. Zebrafish embryos were exposed to various concentrations of 4-MBC in embryo medium for 3 days. In this study, a high concentration of 4-MBC, which is not being expected at the current environmental concentrations in the environment, was used for the purpose of phenotypic screening. Embryos exposed to 15 μM of 4-MBC displayed abnormal axial curvature and exhibited impaired motility. Exposure effects were found to be greatest during the segmentation period, when somite formation and innervation occur. Immunostaining of the muscle and axon markers F59, znp1, and zn5 revealed that 4-MBC exposure leads to a disorganized pattern of slow muscle fibers and axon pathfinding errors during the innervation of both primary and secondary motor neurons. Our results also showed reduction in AChE activity upon 4-MBC exposure both in vivo in the embryos (15 μM) and in vitro in mammalian Neuro-2A cells (0.1 μM), providing a possible mechanism for 4-MBC-induced muscular and neuronal defects. Taken together, our results have shown that 4-MBC is a teratogen and influences muscular and neuronal development, which may result in developmental defects.     

Allocation by Contribution to Cost and Risk at Superfund Sites

Because there is no specific legislative or regulatory guidance, there is no "right" way to allocate liability at Superfund sites. Allocation based on the cost of a remedy, and allocation based on the need for a remedy, i.e. risk-based allocation, represent two possibilities. Other allocation schemes can be located between these two philosophical poles. When waste streams and environmental impacts are qualitatively similar, allocation based solely on costs may make the most sense. When one or more potentially responsible parties (PRPs) have qualitatively different wastes or impacts, an allocation scheme based on both contribution to cost and to risk may be able to incorporate all PRPs. In any case, dissident PRPs, whose contribution to remedy costs is large but whose contribution to risk is small, may find satisfaction in the courts where there is precedent for risk-based allocation.     

Heat illness among high school athletes--United States, 2005-2009

Introduction

Heat illness is a leading cause of death and disability among U.S. high school athletes.

Methods

To examine the incidence and characteristics of heat illness among high school athletes, CDC analyzed data from the National High School Sports-Related Injury Surveillance Study for the period 2005–2009.

Results

During 2005–2009, the 100 schools sampled reported a total of 118 heat illnesses among high school athletes resulting in ≥ 1 day of time lost from athletic activity, a rate of 1.6 per 100,000 athlete-exposures, and an average of 29.5 time-loss heat illnesses per school year. The average corresponds to a weighted average annual estimate of 9,237 illnesses nationwide. The highest rate of time-loss heat illness was among football players, 4.5 per 100,000 athlete-exposures, a rate 10 times higher than the average rate (0.4) for the eight other sports. Time-loss heat illnesses occurred most frequently during August (66.3%) and while practicing or playing football (70.7%). No deaths were reported.

Conclusions

Consistent with guidelines from the National Athletic Trainers’ Association, to reduce the risk for heat illness, high school athletic programs should implement heat-acclimatization guidelines (e.g., set limits on summer practice duration and intensity). All athletes, coaches, athletic trainers, and parents/guardians should be aware of the risk factors for heat illness, follow recommended strategies, and be prepared to respond quickly to symptoms of illness. Coaches also should continue to stress to their athletes the importance of maintaining proper hydration before, during, and after sports activities.

Impact of industry

By implementing preventive recommendations and quickly recognizing and responding to heat illness, coaches, athletic trainers, and the sporting community can prevent future deaths.     

Wind modeling of Chihuahuan Desert dust outbreaks

The Chihuahuan Desert region of North America is a significant source of mineral aerosols in the Western Hemisphere, and Chihuahuan Desert dust storms frequently impact the Paso del Norte (El Paso, USA/Ciudad Juarez, Mexico) metropolitan area. A statistical analysis of HYSPLIT back trajectory residence times evaluated airflow into El Paso on all days and on days with synoptic (non-convective) dust events in 2001–2005. The incremental probability—a measure of the areas most likely to have been traversed by air masses arriving at El Paso during dusty days—was only strongly positively associated with the region west–southwest of the city, a zone of known dust source areas. Focused case studies were made of major dust events on 15 April and 15 December 2003. Trajectories approached the surface and MM5 (NCAR/Penn State Mesoscale Model) wind speeds increased at locations consistent with dust sources observed in satellite imagery on those dates. Back trajectory and model analyses suggested that surface cyclones adjacent to the Chihuahuan Desert were associated with the extreme dust events, consistent with previous studies of dust storms in the Southern High Plains to the northeast. The recognition of these meteorological patterns serves as a forecast aid for prediction of dust events likely to impact the Paso del Norte.