Determining the Costs of Air Pollution Control

A general procedure has been described that can be followed for estimating the cost of reducing air pollution emissions within a metropolitan region. The six step procedure examines emission inventories, regional trends, control trends, alternate control schemes, control costs, and optimum cost-effectiveness. The procedure is illustrated for one emission source in the Delaware Valley. By application of “feasible controls,” automobile emissions were shown to be reduced from 4.5 billion pounds per year in the Region during 1968 to 1.5 billion pounds in the year 2000. Annual control costs during the same period will increase from $30 million to over $300 million per year. This represents a cost increase from $15 per registered vehicle in 1968 to about $58 per vehicle per year in 2000. A method was illustrated for determining minimum cost to achieve any desired degree of emission reduction where alternate feasible control schemes are available. This method is especially useful where the allocation of scarce resources is involved. The general procedure is applicable to any number of pollutants and emission sources, and may be useful for calculations in any metropolitan area. The objectives of the present study are to apply this method to other sources within the Delaware Valley and to determine total regional costs for various levels of emission reduction. As one example of a practical application for this type of analysis, the economic impact of regulatory schemes can be evaluated on a cost-effectiveness basis     

Hunting Effects on Favourable Conservation Status of Highly Inbred Swedish Wolves

The wolf (Canis lupus) is classified as endangered in Sweden by the Swedish Species Information Centre, which is the official authority for threat classification. The present population, which was founded in the early 1980s, descends from 5 individuals. It is isolated and highly inbred, and on average individuals are more related than siblings. Hunts have been used by Swedish authorities during 2010 and 2011 to reduce the population size to its upper tolerable level of 210 wolves. European Union (EU) biodiversity legislation requires all member states to promote a concept called “favourable conservation status” (FCS) for a series of species including the wolf. Swedish national policy stipulates maintenance of viable populations with sufficient levels of genetic variation of all naturally occurring species. Hunting to reduce wolf numbers in Sweden is currently not in line with national and EU policy agreements and will make genetically based FCS criteria less achievable for this species. We suggest that to reach FCS for the wolf in Sweden the following criteria need to be met: (1) a well‐connected, large, subdivided wolf population over Scandinavia, Finland, and the Russian Karelia‐Kola region should be reestablished, (2) genetically effective size (N_e) of this population is in the minimum range of N_e = 500–1000, (3) Sweden harbors a part of this total population that substantially contributes to the total N_e and that is large enough to not be classified as threatened genetically or according to IUCN criteria, and (4) average inbreeding levels in the Swedish population are <0.1. Efectos de la Cacería sobre el Estatus de Conservación Favorable de Lobos Suecos con Endogamia Alta     

Sampling animal association networks with the gambit of the group

Ecologists increasingly use network theory to examine animal association patterns. The gambit of the group (GoG) is a simple and useful assumption for accumulating the data necessary for a network analysis. The gambit of the group implies that each animal in a group is associating with every other individual in that group. Sampling is an important issue for networks in wild populations collected assuming GoG. Due to time, effort, and resource constraints and the difficulty of tracking animals, sampled data are usually a subset of the actual network. Ecologists often use association indexes to calculate the frequency of associations between individuals. These indexes are often transformed by applying a filter to produce a binary network. We explore GoG sampling using model networks. We examine assortment at the level of the group by a single dichotomous trait, along with many other network measures, to examine the effect of different sampling regimes, and choice of filter on the accuracy and precision with which measures are estimated. We find strong support for the use of weighted, rather than filtered, network measures and show that different filters have different effects depending on the nature of the sampling. We make several practical recommendations for ecologists planning GoG sampling.     

Genetic considerations in the prenatal diagnosis of overgrowth syndromes

Large (>90%) for gestational age (LGA) fetuses are usually identified incidentally. Detection of the LGA fetus should first prompt the provider to rule out incorrect dates and maternal diabetes. Once this is done, consideration should be given to certain overgrowth syndromes, especially if anomalies are present. The overgrowth syndromes have significant clinical and molecular overlap, and are associated with developmental delay, tumors, and other anomalies. Although genetic causes of overgrowth are considered postnatally, they are infrequently diagnosed prenatally. Here, we review prenatal sonographic findings in fetal overgrowth syndromes, including Pallister-Killian, Beckwith-Wiedemann, Sotos, Perlman, and Simpson-Golabi-Behmel. We also discuss prenatal diagnosis options and recurrence risks. Copyright © 2009 John Wiley & Sons, Ltd.     

Habitat type-based bioaccumulation and risk assessment of metal and As contamination in earthworms, beetles and woodlice

The present study investigated the contribution of environmental factors to the accumulation of As, Cd, Cu, Pb and Zn in earthworms, beetles and woodlice, and framed within an exposure assessment of the European hedgehog. Soil and invertebrate samples were collected in three distinct habitat types. Results showed habitat-specific differences in soil and invertebrate metal concentrations and bioaccumulation factors when normalized to soil metal concentration. Further multiple regression analysis showed residual variability (habitat differences) in bioaccumulation that could not be fully explained by differences in soil metal contamination, pH or organic carbon (OC). Therefore, the study demonstrated that in bioaccumulation studies involving terrestrial invertebrates or in risk assessment of metals, it is not sufficient to differentiate habitat types on general soil characteristics such as pH and/or OC alone. Furthermore, simple generic soil risk assessments for Cd and Cu showed that risk characterization was more accurate when performed in a habitat-specific way.     

APPLICATION OF ENHANCED ANNEALING TO GROUND WATER REMEDIATION DESIGN1

ABSTRACT: A methodology for ground water remediation design has been developed that interfaces ground water simulation models with an enhanced annealing optimizer. The ground water flow and transport simulators provide the ability to consider site‐specific contamination and geohydrologic conditions directly in the assessment of alternative remediation system designs. The optimizer facilitates analysis of tradeoffs between technical, environmental, regulatory, and financial risks for alternative design and operation scenarios. A ground water management model using an optimization method referred to as “enhanced annealing” (simulated annealing enhanced to include “directional search” and “memory” mechanisms) has been developed and successfully applied to an actual restoration problem. The demonstration site is the contaminated unconfined aquifer referred to as N‐Springs located at Han‐ford, Washington. Results of the demonstration show the potential for improving groundwater restoration system performance while reducing overall system cost.     

Fluoride Emissions and Forest Growth

Abstract

The October 1995 court decision allowing Ethyl Corporation to offer methylcyclopentadienyl manganese tricarbonyl (MMT) for sale to refiners for introduction into unleaded gasoline as an octane enhancer is likely to result in increased fine (PM_2.5) manganese (Mn) concentrations in ambient air. Concern exists regarding possible health effects. In this paper, recent fine Mn concentrations in three monitoring networks and one U.S. Environmental Protection Agency (EPA) study of personal exposure are analyzed. One network consists mainly of rural sites in national parks in the United States, a second consists mainly of urban sites in California, and the third consists mainly of urban sites in Canada where MMT has been used for a number of years. During the late 1980s and early 1990s, mean ambient concentrations ranged from 1 ng/m³ in the mostly rural network to 3 ng/m³ in the mostly urban California network to 12 ng/m³ in the MMT-impacted Canadian network. Several lines of evidence suggested that some of the fine Mn observed in the United States during the 1986-1992 period was contributed by automobiles using leaded gasoline, for which MMT was a registered fuel additive. However, the near-disappearance of leaded gasoline has resulted in a very small portion of fine Mn being attributed to automobiles in the years since 1992.A source apportionment analysis suggested that crustal contributions to ambient fine Mn are on the order of 1-2 ng/m³ in both the United States and Canada.