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For the last seven years, an interdisciplinary course known as "Greener Solutions", offered by the University of California, Berkeley Center for Green Chemistry, has brought together graduate students in chemistry, environmental health, and engineering to understand each other's disciplines, and to work together to develop safer alternatives to hazardous chemicals and manufacturing processes. Through the course, interdisciplinary teams of UC Berkeley students have worked with partner organizations to identify safer alternatives to chemicals of concern, including investigating safer preservatives in personal care products, nonfluorinated durable water-repellant coatings for outerwear, and safer cross-linkers to replace formaldehyde in permanent press textiles and diisocyanates in spray polyurethane foam insulation. Students undertake a bioinspired design process and then assess the potential health and environmental hazards associated with each of their proposed alternatives relative to hazards of the current chemistries. The students generate a focused alternatives assessment that considers technical performance, relative hazard and exposure potential, and feasibility, creating an "opportunity map" for the partner company and, ideally, the industry sector as a whole. The "Greener Solutions" model for interdisciplinary, inquiry-based learning is training a new generation of chemists and engineers in a systems approach to design: one that more fully considers the health and environmental implications of chemical and material choices. An adaptation of the "Greener Solutions" course model to serve undergraduate civil engineering students at University of Victoria, B.C. demonstrates how the course elements can serve a different subject matter and instructional level.

More than 6600 coal-fired power plants serve an estimated five billion people globally and contribute 46% of annual CO2 emissions. Gases and particulate matter from coal combustion are harmful to humans and often contain toxic trace metals. The decades-old Kosovo power stations, Europe's largest point source of air pollution, generate 98% of Kosovo's electricity and are due for replacement. Kosovo will rely on investment from external donors to replace these plants. Here, we examine non-CO2 emissions and health impacts by using inductively coupled plasma mass spectrometry (ICP-MS) to analyze trace metal content in lignite coal from Obilic, Kosovo. We find significant trace metal content normalized per kWh of final electricity delivered (As (22.3 ± 1.7), Cr (44.1 ± 3.5), Hg (0.08 ± 0.010), and Ni (19.7 ± 1.7) mg/kWhe). These metals pose health hazards that persist even with improved grid efficiency. We explore the air-pollution-related risk associated with several alternative energy development pathways. Our analysis estimates that Kosovo could avoid 2300 premature deaths by 2030 with investments in energy efficiency and solar PV backed up by natural gas. Energy policy decisions should account for all associated health risks, as should multilateral development banks before guaranteeing loans on new electricity projects.

Throughout the developing world, over 200 million people drink groundwater containing fluoride concentrations surpassing the World Health Organization's maximum recommended contaminant level (WHO-MCL) of 1.5 mg F-/L, resulting in adverse health effects ranging from mottled tooth enamel to debilitating skeletal fluorosis. Existing technologies to remove fluoride from water, such as reverse osmosis and filtration with activated alumina, are expensive and are not accessible for low-income communities. Our group and others have demonstrated that minimally-processed bauxite ores can remove fluoride to safe levels at a fraction of the cost of activated alumina. We report results from testing for some technical challenges that may arise in field deployment of this technology at large scale, particularly in a sufficiently robust manner for application in development contexts. Anticipating possible modes of failure and addressing these challenges in advance in the laboratory is particularly important for technologies for vulnerable communities where the opportunity to re-launch pilot projects is limited and small failures can keep solutions from the people that need them most. This work addresses three potential technical barriers to reliable removal of fluoride from drinking water with bauxite ore from Visakhapatnam, Andhra Pradesh, India. We evaluate competition from co-occurring ions, adsorption reversibility, and potability of the product water with regards to leaching of undesirable ions during treatment with various adsorbent materials including raw and thermally activated bauxite, and synthetic gibbsite (a simple model system). Under the conditions tested, the presence of phosphate significantly impacts fluoride adsorption capacity on all adsorbents. Sulfate impacts fluoride adsorption on gibbsite, but not on either bauxite adsorbent. Nitrate and silicate (as silicic acid), tested only with gibbsite, do not affect fluoride adsorption capacity. Both thermally activated bauxite and gibbsite show non-reversible adsorption of fluoride at a pH of 6. Raw bauxite leached arsenic and manganese in a TCLP leaching test at levels indicating the need for ongoing monitoring of treated water, but not precluding safe deployment of bauxite as a fluoride remediation technology. Understanding these phenomena is crucial to ensure field deployment over large diverse geographical areas with aquifers varying in groundwater composition, and for ensuring that the appropriate engineering processes are designed for field implementation of this innovation.

Preservatives deter microbial growth, providing crucial functions of safety and durability in composite materials, formulated products, and food packaging. Concern for human health and the environmental impact of some preservatives has led to regulatory restrictions and public pressure to remove individual classes of compounds, such as parabens and chromated copper arsenate, from consumer products. Bans do not address the need for safe, effective alternative preservatives, which are critical for both product performance (including lifespan and therefore life cycle metrics) and consumer safety. In this work, we studied both the safety and efficacy of a series of phenolic preservatives and compared them to common preservatives found in personal care products and building materials. We quantified antimicrobial activity against Aspergillus brasiliensis (mold) and Pseudomonas aeruginosa (Gram negative bacteria), and we conducted a hazard assessment, complemented by computational modeling, to evaluate the human and environmental health impacts of these chemicals. We found that octyl gallate demonstrates better antimicrobial activity and comparable or lower hazards, compared to current-use preservatives. Therefore, octyl gallate may serve as a viable small-molecule preservative, particularly in conjunction with low concentrations of other preservatives that act through complementary mechanisms.

The first synthesis and structural characterization of actinide corroles is presented. Thorium(IV) and uranium(IV) macrocycles of Mes2(p-OMePh)corrole were synthesised and characterized by single-crystal X-ray diffraction, UV-Visible spectroscopy, variable-temperature 1H NMR, ESI mass spectrometry and cyclic voltammetry.

Several principles of green chemistry are introduced through this experiment designed for use in the undergraduate analytical chemistry laboratory. An established experiment of liquid CO2 extraction of D-limonene has been adapted to include a quantitative analysis by gas chromatography. This facilitates drop-in incorporation of an exciting experiment into an existing curriculum. The experiment provides an introduction to natural product extraction, calibration curves, and internal standards while simultaneously demonstrating alternative solvent selection for pollution prevention and increased chemical safety.