Green Assessment for Analytical Methods Julee Driver*, Douglas Raynie SDSU Chemistry and Biochemistry

Why does green matter? Energy consumption Environment Health Safety Life Energy consumption Safety Environment Health Why do we care if something is green? Could hurt our environment – sustainability – hurt future generations. Could harm us – toxicity. Petroleum as an energy source is limited in quantity – need to conserve. Some products/methods/processes are greener than others and often there are alternatives available should one wish to operate in a greener manner.

Opportunities for greenness Solvents, Reagents Equipment, Instrumentation Sample prep. Analysis Take sample – sample type and amount; Analysis – sample prep time, analysis time.

Non-green consequences Solvents, reagents Toxicity, Bioaccumulation, Persistence Reactivity, Flammability, Waste Equipment, instrumentation Safety Energy Sample prep. Waste Analysis

12 principles of green chemistry 1. Prevent waste. 2. Maximize atom economy. 3. Design less hazardous chemical synthesis. 4. Design safer chemicals. 5. Use safer solvents and reaction conditions. 6. Design for energy efficiency. 7. Use renewable feedstocks. 8. Reduce use of derivatives. 9. Use catalysts. 10. Design for degradation. 11. Analyze in real time. 12. Minimize potential for accidents.

Green assessment criteria Environmental hazard Greenhouse gas chemical Ozone depletion Ozone generation Persistent, bioaccumulative Health hazard Toxicity Carcinogenicity Irritant Safety hazard Flammability Corrosivity Reactivity Waste Properties Air, land, water emissions Waste amount Energy Efficiency Solvent evaporation Instrumentation use

Other assessments ‘Greenness Profile’ Developed by ACS Green Chemistry Institute in collaboration with 25 environmental method experts Profile was published and applied to methods in NEMI database Criteria evaluated: PBT Hazard Corrosive Waste amount PBT – meant included in EPT TRI PBT list; hazard meant included in EPT TRI listed chemical, RCRA D,K,P,U; corrosive by pH; Waste amount greater than 50 grams.

Other assessments – ‘Greenness profile’ Criterion score: Green Less green Criterion How to decide? PBT Is chemical listed on EPA’s TRI PBT? Hazard Is chemical listed on EPA’s TRI1 or RCRA subpart D (F, P, or U)? Corrosive Is pH during analysis < 2 or > 12? Waste Amount Is the waste > 50 g? ‘Quantitative’ value assigned to each criteria = ‘Green’ or ‘less green’; For each, if yes then assignment is ‘less green’, if no then assignment is ‘green’; Basically pass or fail.

Other assessments - ‘Greenness Profile’ Profile symbol PBT Hazard Corrosive Waste

Other assessments – ‘Green index value’ * Developed by Rich Gurney, Simmons College

Assessment comparison 12 Principles of Green Chemistry GCI – NEMI GIV Dolphin This assessment Waste X Toxicity Environmental persistence Accident potential Energy efficiency Renewable feedstocks

Greenness assessment for analytical methods Goals for new assessment: User friendly Have a clear and simple evaluation process Increase the range of discrimination possible Of methods in NEMI database, 2/3 fail waste. If nearly all fail, is the evaluation effective? Possible to differentiate between how badly one fails? Include energy use as a criteria Develop assessment which can be applied to any chemical process

Greenness assessment criteria Flammability Health hazard Reactivity 4. Use and generate substances that possess little or no toxicity to human health and the environment Specific hazard NFPA Hazard Symbol

Green assessment – health criteria NFPA score 0 = most green = minimal or slight toxicity Recognized innocuous, minor irritation possible 2 = less green = moderate toxicity Intense or continued exposure could cause temp. incapacitation or residual injury 4 = least green = serious toxicity Serious temp. or residual injury on short term exposure or a known or suspected human carcinogen Since NFPA ratings are a guide for much of our analysis, I’ll give an example of the meaning of their ratings; health is the blue quadrant; give an example – say cyclohexane has a ‘4’ health rating because…

Green assessment – scoring criteria 1 = 2 = 3 =

Green assessment – health hazard 1 = 2 = 3 = Slightly toxic, slight irritant; NFPA health hazard score is 0 or 1. Moderately toxic; could cause temporary incapacitation; NFPA = 2. Serious injury on short term exposure; known or suspected small animal carcinogen; NFPA = 3 or 4.

Green assessment – safety hazard 1 = 2 = 3 = Based on NFPA flammability, reactivity, special hazard ratings

Green assessment – environmental hazard 1 = 2 = 3 = Based on use or generation of: Greenhouse gas generators Ozone generators Ozone depleters Persistance Bioaccumulation

Green assessment – waste properties 1 = 2 = 3 = Based on ratio of waste to sample size Type of waste also considered

Green assessment – energy 1 = 2 = 3 = Wet chemistry method. Instrumental method such as GC, HPLC; extensive solvent evaporation required. Instrumental method such as ICP-MS; or AA.

Green assessment - profile Health Environmental Energy Waste F Safety

Aknowledgements Paul T. Jackson, PhD Associate professor St. Olaf College, Northfield MN Jennifer Young, PhD Senior program manager ACS Green Chemistry Institute