Examining the temperature dependence of ethanol (E85) versus gasoline emissions on air pollution with a largely-explicit chemical mechanism

The increased use of ethanol in transportation fuels warrants an investigation of its consequences. An important component of such an investigation is the temperature dependence of ethanol and gasoline exhaust chemistry. We use the Master Chemical Mechanism (MCM, version 3.1, LEEDS University) with the SMVGEAR II chemical ordinary differential solver to provide the speed necessary to simulate complex chemistry to examine such effects. The MCM has over 13,500 organic reactions and 4600 species. SMVGEAR II is a sparse-matrix Gear solver that reduces the computation time significantly while maintaining any specified accuracy. Although we use a box model for this study, we determine and demonstrate in a separate study that the speed of the MCM with SMVGEAR II allows the MCM to be modeled in 3-dimensions. We also verified the accuracy of the model in comparison with smog chamber data. We then use the model with species-resolved tailpipe emissions data for E85 (15% gasoline, 85% ethanol fuel blend) and gasoline vehicles to compare the impact of each on nitrogen oxides, organic gases, and ozone as a function of ambient temperature and background concentrations, using Los Angeles in 2020 as a base case. We use two different emissions sets – one is a compilation of exhaust and evaporative data taken near 24 °C and the other from exhaust data taken at ?7 °C – to determine how atmospheric chemistry and emissions are affected by temperature. We include diurnal effects by examining two day scenarios. We find that, accounting for chemistry and dilution alone, the average ozone concentrations through the range of temperatures tested are higher with E85 than with gasoline by ～7 part per billion volume (ppbv) at higher temperatures (summer conditions) to ～39 ppbv at low temperatures and low sunlight (winter conditions) for an area with a high nitrogen oxide (NOx) to non-methane organic gas (NMOG) ratio. The results suggest that E85's effect on health through ozone formation becomes increasingly more significant relative to gasoline at colder temperatures due to the change in exhaust emission composition at lower temperatures. Acetaldehyde and formaldehyde concentrations are also much higher with E85 at cold temperatures, which is a concern because both are considered to be carcinogens. These could have implications for wintertime use of E85. Peroxy acetyl nitrate (PAN), another air pollutant of concern, increases with E85 by 0.3–8 ppbv. The sensitivity of the results to box size, initial background concentrations, background emissions, and water vapor were also examined.     

Body mass index and serum chlorinated dibenzo-p-dioxin and dibenzofuran levels

Several studies have found that current levels of 2,3,7,8 tetrachlorodibenzo-p-dioxin in serum lipids are related to age with older persons generally having higher levels. To account for this age pattern, reference ranges based on national samples have been established in order to allow determination of background levels for regional studies. In several studies, body mass index (BMI), has also been associated with current 2,3,7,8 tetrachlorodibenzo-p-dioxin levels with increasing body mass index related to increasing levels. We measured lipid-adjusted serum levels for all 2,3,7,8-substituted dioxins and furans in 62 chemical manufacturing workers with chlorophenol exposures and 36 workers without chlorophenol exposures employed at the same location. We then assessed the impact of age and BMI on the serum levels of all these compounds in the presence of other potential confounders. We found that both factors are important independent determinants of serum levels of 2,3,7,8-substituted dioxins and furans. Specifically, age and BMI are both important factors for assessing background levels of 2,3,7,8 tetrachlorodibenzo-p-dioxin, 1,2,3,7,8 pentachlorodibenzo-p-dioxin and the calculated total toxic equivalency. BMI, but not age, is important for assessing background levels of higher chlorinated dioxins and some hexachlorofurans. We conclude that age and BMI are both important considerations when comparing a potentially exposed group to a referent group, or to national norms. Further, age and BMI may also be important in epidemiology studies where back-extrapolation from current dioxin levels is used to assess historical chlorophenol exposure.     

Unilateral Clean Development Mechanism – An approach for a least developed country?: The case of Yemen

Decision parameters prevailing in the market lead to a slim expression of interest of foreign investors for Clean Development Mechanism (CDM) projects in a bi- or multilateral design in Yemen. The Designated National Authority Secretariat in Yemen experiences the preference of Annex I entities of merely buying Certified Emission Reductions rather than investing in projects. Yemen's ability, like many least developed countries, to carry out unilateral CDM projects is moderate. Domestic project developers perceive difficulties in procuring underlying finance as key barrier in materializing CDM project activities in a unilateral design. The country remains trapped in a “catch 22 situation”. International assistance through low interest loans and capacity building for domestic financial institutions tailored to CDM project activities may trigger the market. Aggravation can be assisted by amending the policies of Annex I countries, in consequence to allocate a substantial share of their procurement activities to Certified Emission Reductions from least developed countries. Acquisition programmes may give preference to projects from host countries not traditionally represented in the pool of attractive CDM destinations.     

The rich get richer: predicting participation in voluntary diversity training

This research examined whether trainee demographics and pre‐training competence predicted participation in voluntary diversity training. Results indicate that demographic variables had no impact on interest in training (Study One) or on actual training participation (Study Two). However, pre‐training competence levels had a positive effect on both outcomes. More competent trainees expressed more interest in additional training (Study One) and were more likely to attend a voluntary training session (Study Two). The authors suggest that trainees with low competence in the diversity domain are unaware of their low competence levels and therefore are not motivated to participate in training programs designed to increase diversity competence. Implications of these findings for organizations offering voluntary diversity training are discussed. Copyright © 2007 John Wiley & Sons, Ltd.     

Mining amid decentralization. Local governments and mining in the Philippines

In recent years, as part of its neoliberal development paradigm, the Government of the Philippines has engaged in efforts to encourage extraction of the nation's mineral resources. The Philippines is also a country where decentralization has devolved substantial powers to local governments. Concern over potentially adverse environmental effects has led to opposition to mining by some local governments in the Philippines. This opposition has led to the withholding of consent to mining projects by local governments and, in some cases, the implementation of moratoriums banning mining. Central to this opposition have been the activities of civil society groups, and their collaboration with local governments. This collaboration has involved the drafting of legislation prohibiting mining and support of candidates for office who are opposed to mining. Collectively, Filipino local governments and civil society groups are examples of the concept of governance, a dispersed process wherein society manages itself for the betterment of all its members. For mining companies seeking to implement projects, it is no longer sufficient to have the consent of the national Government — that of local governance forces must also be considered.     

Managing Radioactively Contaminated Land: Implications for Habitat Diversity

Radioactive contamination of agricultural land may necessitate long-term changes in food production systems, through application of selected countermeasures, in order to reduce the accumulation of radionuclides in food. We quantified the impact of selected countermeasures on habitat diversity, using the hypothetical case of two agricultural areas in Finland. The management scenarios studied were conversions from grassland to cereal production and from grassland and crop production to afforestation. The two study sites differed with respect to present agricultural production: one being predominantly cereal production and seminatural grasslands, while the other was dominated by intensive grass and dairy production. Some of the management scenarios are expected to affect landscape structures and habitat diversity. These potential changes were assessed using a spatial pattern analysis program in connection with geographic information systems. The studied landscape changes resulted in a more monotonous landscape structure compared to the present management, by increasing the mean habitat patch size, reducing the total habitat edge length and reducing the overall habitat diversity calculated by the Shannon diversity index. The degree of change was dependent on the present agricultural management practice in the case study sites. Where dairy production was predominant, the landscape structure changes were mostly due to conversion of intensive pastures and grasslands to cereal production. In the area dominated by cereal production and seminatural grasslands, the greatest predicted impacts resulted from afforestation of meadows and pastures. The studied management changes are predicted to reduce biodiversity at the species level as well as diminishing species-rich habitats. This study has predicted prominent side effects in habitat diversity resulting from application of management scenarios. These potential long-term impacts should be considered by decision-makers when planning future strategies in the event of radionuclide deposition.