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Chapter 7 Out of the Frying Pan …... PFCs A Summary of Key Concepts Perfluorinated compounds (PFCs) are fluorine- containing chemicals with stain and.

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Presentation on theme: "Chapter 7 Out of the Frying Pan …... PFCs A Summary of Key Concepts Perfluorinated compounds (PFCs) are fluorine- containing chemicals with stain and."— Presentation transcript:

1 Chapter 7 Out of the Frying Pan …..

2 PFCs A Summary of Key Concepts Perfluorinated compounds (PFCs) are fluorine- containing chemicals with stain and stick resistant qualities. PFCs are incredibly resistant to breakdown and are turning up in unexpected places around the world. There are many forms of PFCs, but the two getting attention recently are: PFOA or perfluorooctanoic acid, used to make Teflon products. PFOS or perfluorooctane sulfonate, a breakdown product of chemicals formerly used to make Scotchgard products.

3 “Safer” alternatives ? New products on the market claiming to be “environmentally safe” or “PFOA-free” Some (like “Scanpan”) contain polytetrafluoroethylene (PTFE), the monomer compound of Teflon. – While the product itself may be “PFOA-free,” the production of PTFE requires PFOA

4 C8 & C6: ‘Christmas Tree’ polymers PFOA also called C8 due to the 8 carbon atoms at its core EWG scientist Olga Nadeinko compares the PFOA polymer to a Christmas tree: “[T]he carbon backbone of the molecule is the trunk of the tree and the side chains with the fluorine atoms are the branches” (135) Eventually, these “branches” will break off from the molecule.

5 NY Times January 10, 2016

6 Chapter 8 NanoTechnology

7 One billionth of a meter, or:

8  Synthetic materials manufactured on the atomic scale of one to 100 nanometers are called “nanomaterials.” So tiny, that they are manipulated on the atomic level  These materials can absorb special wavelengths of light, making them susceptible to dyes and medical tracers.  Since nanomaterials can be absorbed through the skin and are able to seep into organs and to cell membranes, they can be used in the medical field for treatment. But, they can also unintentionally reach the wrong organs  Although nanotechnology is not “green” in and of itself, what makes it green are the opportunities it can potentially create. Materials can be resource-efficient, reducing waste during manufacture.

9 It is the science and technology of building products from single atoms and molecules.

10 Chapter 9 Material Consequences Toward a Greening of Chemistry

11 Ethics Society today requires a new approach to ethics, because people now have the ability to affect thousands lives simply from making every day decisions. This also applies to corporations, whose decisions influence the public on a large, global scale.

12 On the Road to Change Since there were very few regulations when chemists first started synthesizing compounds; many of the processes used need to be revamped, in order to adhere to a new green code ethics.

13 Incorporating Ethics Businesses that manufacture and market synthesized molecules are currently transitioning between methods of production. It was once acceptable to produce and regulate chemicals in the cheapest way possible. However with increasing awareness of environmentally risk, it is now increasing unacceptable to use wasteful and/or“dirty” processes.

14 The Equation Not only is it important that synthesized compounds be produced as efficiently as possible, the end result should meet its purpose with minimal toxicity. Not only is it important that synthesized compounds be produced as efficiently as possible, the end result should meet its purpose with minimal toxicity. Risk= Hazard x Exposure Risk= Hazard x Exposure Though it seems relatively basic, most chemists are never even trained in toxicology. Though it seems relatively basic, most chemists are never even trained in toxicology. The desire to produce chemicals from renewable resources is helping to replace some compounds with ones that are less toxic. The desire to produce chemicals from renewable resources is helping to replace some compounds with ones that are less toxic.

15 Liz Grossman “Chasing Molecules” Epilogue Introduction to Green Chemistry Problems unassessable, lifelong, additive, incidental, low dose exposure; “endless end-of-pipe” control FDA => only ca. 3,112 intentionally active drugs (39 new in 2011; 45 in 2015) Solutions design out toxicity as a property; regulation on the basis of intentional molecular design

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18 The Drivers of Green Chemistry The STEEP model: Social Technological Economic Environmental PoliticalSocialTechnologicalEconomicEnvironmental Political Social factors relate to the society and the social systems we live in. It includes demographics, lifestyle aspirations, choices, patterns of work and leisure, mobility and migration, and requirements for security, shelter and food. The elements of Maslow’s Hierarchy of Needs. Technological factors relate to the way that broad technological development changes the industrial environment. It includes changes in the way we can manipulate materials, delivery systems, packaging, transportation, communication, information systems and new business models. Economic factors relate to the impact of local and global financial systems on local, global, national, corporate and personal levels. Access to finance, management of risk, and exploitation of differing cost structures across the globe. Environmental factors relate to the physical environment in which we live. It includes resource consumption, waste generation and disposal, end of life disposal, environmental and health impacts and risks. Political factors relate to the systems that govern us at the global, national and local levels. It includes policy, regulation, laws, legislation, and the political processes that drive them.

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20 Green Chemistry - Principles “As to methods, there may be a million and then some, but principles are few. The man who grasps principles can successfully select his own methods. The man who tries methods, ignoring principles, is sure to have trouble.” Ralph Waldo Emerson

21 The Twelve Principles of GREEN CHEMISTRY (Anastas and Warner 1998) 1. It is better to prevent waste than to treat or clean up waste after it is formed. 2. Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product. Called Atom Economy. % Atom Economy = (MW of product/MW of all reactants) x 100 3. Wherever practicable, synthetic methodologies should be designed to use and generate substances that possess little or no toxicity to human health and the environment. 4. Chemical products should be designed to preserve efficacy of function while reducing toxicity. 5. The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made unnecessary whenever possible and innocuous when used. 6. Energy requirements should recognized for their environmental and economic impacts and should be minimized. Synthetic methods should be conducted at ambient temperature and pressure.

22 The Twelve Principles of GREEN CHEMISTRY (Anastas and Warner 1998) 7. A raw material feedstock should be renewable rather than depleting whenever technically and economically practical. 8. Unnecessary derivatization (blocking group, protection/deprotection, temporary modification of physical/chemical processes) should be avoided whenever possible. 9. Catalytic reagents (as selective as possible) are superior to stoichiometric reagents. 10. Chemical products should be designed so that at the end of their function they do not persist in the environment and break down into innocuous degradation products. 11. Analytical methodologies need to be further developed to allow for real-time in-process monitoring and control prior to the formation of hazardous substances. 12. Substances and the form of a substance used in a chemical process should be chosen so as to minimize the potential for chemical accidents, including releases, explosions, and fires.

23 Green Chemistry is Accomplished Productively S.L.Y. Tang, R.L. Smith and M. Poliakoff, Green Chemistry, 2005, 7, 761 P - Prevent Waste – The Guiding Principle - Others are “How To’s” R - Renewable Materials O - Omit Derivitazation Steps D - Degradable Chemical Product U - Use Safe Chemicals and Synthetic Methods C - Catalytic Reagents T - Temperature and Pressure Ambient I - In Process Real Time Analytical Monitoring V - Very Few Auxiliary Substances E - E factor, Maximize Starting Materials in Product L - Low Toxicity of Feed stocks, Reagents and Products Y - Yes, It Is Safe !

24 The T oxic S ubstances C ontrol A ct of 1976 http://www3.epa.gov/enviro/ http://www3.epa.gov/enviro/ 15 U.S.C. §2601 et seq. (1976) Provides the EPA with authority to: Require reporting, record-keeping and testing requirements, and restrictions relating to chemical substances and/or mixtures. Certain substances are generally excluded from TSCA, including, food, drugs, cosmetics and pesticides.

25 http://www.epa.gov/opptintr/existi ngchemicals/pubs/principles.html Toxic Substances Control Act 1976 List not Regulation 62,000 grandfathered chemicals Since 1976 only 200 tested; 5 regulated Burden of Proof requires EPA to certify “unsafeness” High Bars to Banning – Three hurdles See page 126 1) Chemicals presents unreasonable health or environmental risk 2) Human exposure is significant 3) Existing information is insufficient to address health impacts

26 http://www.epa.gov/opptintr/existing chemicals/pubs/principles.html

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