Materials Balance for Bromine, Chlorine, Sulfur, and Nitrogen in Europe

An understanding of the flow of toxic materials through industry and into the environment is one of the major tasks for the IIASA Study, "The Future Environments for Europe: Some Implications, of Alternative Development Paths". Toxic chemicals represent a great threat to the environment, and yet they are commonly used in industrial societies. A sustainable development path would require that usage and disposal of toxic chemicals be compatible with the long-term health of humans and the natural environment. Examining the current and past flows of these materials is a starting point for understanding options for management of their use and disposal, and the impact these options might have on the economy and society. The method chosen to analyze this problem is a materials balance approach in which toxic chemicals are traced as they move through the industrial economy; from extraction to production to intermediate uses and finally to end uses. The methodology and its advantages and disadvantages are discussed in some detail in Chapter 2. The implementation of this approach will become apparent in Chapters 3 through 6 as four individual chemical elements are studied. The four elements examined are bromine, chlorine, sulfur and nitrogen. These chemicals were chosen from a list of 15 which were of particular interest because of the exceptional biological activity of many of the compounds derived from them. The major goal of the project was to develop process-product flow diagrams for these elements showing their pathways through the industrial economy. Each of Chapters 3 through 6 contains a discussion of production processes, major uses, process-product flow diagram(s) and an Appendix with detailed information about the chemical transformations involved in each of the processes. In addition, further investigations including quantitative analysis and discussions of the applicability of this approach for a given element are included in some of the Chapters. Chapter 3, Bromine, presents a detailed qualitative material balance and a more aggregated quantitative material balance for the Netherlands and the United States for 1978 and 1985. The selection of these two countries was based solely on available data. Although the U.S. is not formally part of the study, it is useful as it more closely represents the Western European consumption pattern on average than the Netherlands. While the quantitative analysis focuses only on two countries for two years, it does demonstrate both the qualitative and quantitative aspects of the material balance approach. Bromine consumption is an interesting case as it has been heavily impacted by the phase-out of leaded gasoline and strong market shifts are expected in the future. Chapter 4, Chlorine, presents an in-depth qualitative materials balance and a look at the pathways of chlorine into the environment based on its pattern of end-use consumption. Currently, millions of tons of chlorine are produced each year for use as a disinfectant and in the organic and inorganic chemical industries. Many of the end-uses of chlorine result in eventual releases into the environment of various compounds which have a significant effect on environmental quality. Organic chlorine compounds are of great use to man because they are not readily biodegradable and they are chemically stable. However, because of these qualities they represent some of the most difficult disposal problems of any anthropogenic material. Chapter 5, Sulfur, presents a thorough qualitative analysis of the industrial processes and an in-depth discussion of the applicability of the materials balance approach to sulfur. A large portion of anthropogenically mobilized sulfur is from the burning of fossil fuels and the smelting of ores, two processes where sulfur is not an intentional product, simply an unavoidable one. The bulk of scientific study of sulfur wastes is concentrated on these areas due to their contribution to the acid rain problem. The analysis presented here shows that over half of the total anthropogenic sulfur budget in Europe is from industrial sources other than fossil fuels and ore smelting. This is a fairly surprising result. Thus, the flow of sulfur through the industrial economy in Europe is significant and greater understanding of the eventual disposal of this sulfur is needed. In addition, sulfuric acid is the number one industrial chemical based on the tonnage of production. It is used in a myriad of industries where it is generally consumed in the process and not embodied in the end product. This presents difficulties in the implementation of the materials balance analysis for sulfur. Chapter 6, Nitrogen, presents the process-product flow diagram for nitrogen. About 95% of the anthropogenically mobilized nitrogen is in the form of ammonia. Therefore, this chapter concentrates on the production and eventual end-uses of ammonia. While the process-product diagram is quite thorough, due to time constraints, further discussion and analysis of nitrogen is left as a future research topic. This report is the first step toward completing the task of understanding the impact of toxic materials in Europe. Future analysts may use the process-product diagrams and the analysis presented in this report as a starting point for a historical reconstruction which then could be used for building future scenarios of chemical flows of toxic materials

Industrial Metabolism, the Environment, and Application of Materials-Balance. Principles for Selected Chemicals

This report provides an important step in our understanding of material flows for four widely used inorganic chemicals, bromine, chlorine, sulfur, and nitrogen. Also, by invoking the concept of industrial metabolism, the authors provide a new vision for understanding how industrial sciences produce, process, use, and dispose of materials, and how these activities, taken as a whole, are linked to environmental change

Utilization of Renewable Oxygenates as Gasoline Blending Components

This report reviews the use of higher alcohols and several cellulose-derived oxygenates as blend components in gasoline. Material compatibility issues are expected to be less severe for neat higher alcohols than for fuel-grade ethanol. Very little data exist on how blending higher alcohols or other oxygenates with gasoline affects ASTM Standard D4814 properties. Under the Clean Air Act, fuels used in the United States must be 'substantially similar' to fuels used in certification of cars for emission compliance. Waivers for the addition of higher alcohols at concentrations up to 3.7 wt% oxygen have been granted. Limited emission testing on pre-Tier 1 vehicles and research engines suggests that higher alcohols will reduce emissions of CO and organics, while NOx emissions will stay the same or increase. Most oxygenates can be used as octane improvers for standard gasoline stocks. The properties of 2-methyltetrahydrofuran, dimethylfuran, 2-methylfuran, methyl pentanoate and ethyl pentanoate suggest that they may function well as low-concentration blends with gasoline in standard vehicles and in higher concentrations in flex fuel vehicles

Validating Chemistry Faculty Members’ Self-Reported Familiarity with Assessment Terminology

With the increasing emphasis placed upon chemistry instructors and departments to assess and evaluate their courses and curricula, understanding the structure of chemistry faculty members’ knowledge and use of assessment terms and concepts can shed light on potential areas for targeted professional development. Survey research that might accomplish this objective often relies on self-reported responses from the target audience, and such information is sometimes difficult to assess in terms of validity. As an example of an internal mechanism to help establish validity, it is possible to include an “internal standard” item early in the survey. For the sake of understanding faculty members’ familiarity with assessment terminology, an item that asked participants to identify analogous pairs of terms comparing assessment measures (assessment validity and assessment reliability) to laboratory measures (accuracy and precision) served this purpose. Using ordered logistic regression, participants who answered the analogy question completely correctly were more likely to report higher levels of familiarity with the assessment terms. Because the self-reported data appears to be valid, these data can be further used in subsequent analyses in order to determine the general familiarity trends among chemistry faculty regarding assessment terminology

Occurrence of exercise-induced and spontaneous wide complex tachycardia during therapy with flecainide for complex ventricular arrhythmias: A probable proarrhythmic effect

Flecainide acetate, a new antiarrhythmic agent, possesses favorable pharmacokinetic and hemodynamic properties and demonstrates highly favorable antiarrhythmic activity in patients with ventricular arrhythmias. However, the proarrhythmic potential of flecainide deserves further evaluation. In 7 (13%) of 55 consecutive patients treated with oral flecainide, 200 to 600 mg/day, for complex ventricular arrhythmias (including sustained ventricular tachycardia in 14), we observed the appearance of new or more sustained exercise-induced (five patients) or spontaneous (two patients) wide complex tachycardia. The mechanism of wide complex tachycardia appeared to be ventricular tachycardia in all seven. In our series, episodes were self-remitting or successfully treated. In four patients, wide complex tachycardia did not recur during exercise testing during alternative antiarrhythmic therapy (three patients) or no antiarrhythmic therapy (one patient). These observations raise the possibility of flecainide-related proarrhythmia, manifested as an increased propensity to exercise (activity)-induced wide complex tachycardia, which was not reliably predicted by results of Holter recordings or programmed electrical stimulation. Patients with complex ventricular arrhythmias beginning long-term treatment with oral flecainide should be considered for treadmill exercise testing together with ambulatory monitoring as part of the initial assessment of drug efficacy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26728/1/0000278.pd

Airborne Emissions from 1961 to 2004 of Benzo[a]pyrene from U.S. Vehicles per km of Travel Based on Tunnel Studies

We identified 13 historical measurements of polycyclic aromatic hydrocarbons (PAHs) in U.S. vehicular traffic tunnels that were either directly presented as tailpipe emission factors in μg per vehicle-kilometer or convertible to such a form. Tunnel measurements capture fleet cruise emissions. Emission factors for benzo[a]pyrene (BaP) for a tunnel fleet operating under cruise conditions were highest prior to the 1980s and fell from more than 30-μg per vehicle-km to approximately 2-μg/km in the 1990s, an approximately 15-fold decline. Total annual U.S. (cruise) emissions of BaP dropped by a lesser factor, because total annual km driven increased by a factor of 2.7 during the period. Other PAH compounds measured in tunnels over the 40-year period (e.g., benzo[ghi]perylene, coronene) showed comparable reduction factors in emissions. PAH declines were comparable to those measured in tunnels for carbon monoxide, volatile organic compounds, and particulate organic carbon. The historical PAH “source terms” determined from the data are relevant to quantifying the benefits of emissions control technology and can be used in epidemiological studies evaluating the health effects of exposure, such as those undertaken with breast cancer in New York State

Health Outcomes of Gastric Bypass Patients Compared to Nonsurgical, Nonintervened Severely Obese

Favorable health outcomes at 2 years postbariatric surgery have been reported. With exception of the Swedish Obesity Subjects (SOS) study, these studies have been surgical case series, comparison of surgery types, or surgery patients compared to subjects enrolled in planned nonsurgical intervention. This study measured gastric bypass effectiveness when compared to two separate severely obese groups not participating in designed weight-loss intervention. Three groups of severely obese subjects (N = 1,156, BMI ≥ 35 kg/m2) were studied: gastric bypass subjects (n = 420), subjects seeking gastric bypass but did not have surgery (n = 415), and population-based subjects not seeking surgery (n = 321). Participants were studied at baseline and 2 years. Quantitative outcome measures as well as prevalence, incidence, and resolution rates of categorical health outcome variables were determined. All quantitative variables (BMI, blood pressure, lipids, diabetes-related variables, resting metabolic rate (RMR), sleep apnea, and health-related quality of life) improved significantly in the gastric bypass group compared with each comparative group (all P < 0.0001, except for diastolic blood pressure and the short form (SF-36) health survey mental component score at P < 0.01). Diabetes, dyslipidemia, and hypertension resolved much more frequently in the gastric bypass group than in the comparative groups (all P < 0.001). In the surgical group, beneficial changes of almost all quantitative variables correlated significantly with the decrease in BMI. We conclude that Roux-en-Y gastric bypass surgery when compared to severely obese groups not enrolled in planned weight-loss intervention was highly effective for weight loss, improved health-related quality of life, and resolution of major obesity-associated complications measured at 2 years

Analysis of long-term observations of NOx and CO in megacities and application to constraining emissions inventories

Long-term atmospheric NOx/CO enhancement ratios in megacities provide evaluations of emission inventories. A fuel-based emission inventory approach that diverges from conventional bottom-up inventory methods explains 1970–2015 trends in NOx/CO enhancement ratios in Los Angeles. Combining this comparison with similar measurements in other U.S. cities demonstrates that motor vehicle emissions controls were largely responsible for U.S. urban NOx/CO trends in the past half century. Differing NOx/CO enhancement ratio trends in U.S. and European cities over the past 25 years highlights alternative strategies for mitigating transportation emissions, reflecting Europe's increased use of light-duty diesel vehicles and correspondingly slower decreases in NOx emissions compared to the U.S. A global inventory widely used by global chemistry models fails to capture these long-term trends and regional differences in U.S. and Europe megacity NOx/CO enhancement ratios, possibly contributing to these models' inability to accurately reproduce observed long-term changes in tropospheric ozone