Abstract Method Discussion Background Results References The Dose Makes the Poison: Measuring Ecotoxicity Using Lettuce Seed Assay Elizabeth Pellerin eak465@wildcats.unh.edu University of New Hampshire Abstract Method Discussion The results showed that methanol was the least toxic alcohol to the lettuce seeds. Although methanol is least toxic to plants it is the most toxic of the three alcohols to humans. Methanol occurs naturally during the decomposition of different plants and animals in our environment. When methanol is released into the environment it quickly biodegrades. How does measuring ecotoxicity using a lettuce seed assay relate to green chemistry? Design Less Hazardous Chemical Syntheses-"Wherever practicable, synthetic methods should be designed to use and generate substances that possess little or no toxicity to human health and the environment.” Methanol is naturally occurring and performs biodegradable traits if present in the environment. Use Safer Solvents/Reaction Conditions-"The use of auxiliary substances (e.g., solvents, separation agents, etc.) should be made unnecessary wherever possible and innocuous when used.” This reaction minimizes toxicity to human health and the environment because the isopropanol and ethanol are easily disposed. How does measuring ecotoxicity using a lettuce seed assay relate to organic chemistry? Bio-fuels-The alcohols used in this experiment are commonly used in the preparation of bio- diesel. Measurement/Analysis-This experiment provides quantitative/qualitative data of the effects of varying concentrations has on lettuce seed assays. Toxicology- Is the branch of science that studies nature, effects and detection of poisons. In this experiment the concentrations of alcohols used on the lettuce seeds were very poisonous at higher concentrations. Interestingly enough methanol was the least toxic to the lettuce seed assays. Environmental Chemistry- Studies the biochemical effects that occur in nature. It’s important we understand what chemicals are toxic to the environment so we can make better environmental choices Various alcohol concentrations were distributed among the petri dishes which contained 15 seeds each. Each petri-dish was sealed with parafilm in an undisturbed area with no additional supplemental light at room temperature. The germination and root elongation period was five days After five days the root length and the amount of seeds germinated were counted and recorded. Each petri dish’s root length in centimeters was averaged and recorded. Ecotoxicity refers to the potential biological, chemical or physical stressors that effect an ecosystems. The purpose of this study was to compare the toxicity of methanol, ethanol and isopropanol to see if these alcohols effect the germination and root elongation of a lettuce seed assay. Methanol is very toxic to human beings but interestingly enough it’s the least toxic to the lettuce seeds. Experimental alcohol concentrations Seeded petri-dishes covered with parafilm Root length being measured Background Results References Germination results in different experimental containers after five days Ecotoxicity involves the effects of toxic chemicals on biological organisms, especially at the population, community, ecosystem level A common assay is an investigative procedure used in a lab to access qualitative or quantitative measures of functional activity of a target entity (analyte) in the experiment. The assay typically aims to measure an intensive property of the analyte and expresses it in a relevant unit of measurement (for ex. the effects of concentration has in comparison to the control etc.) Common assays are available for aquatic and terrestrial ecotoxicity. This experiment introduced terrestrial ecotoxicity of different alternative starting materials commonly used for the preparation of biodiesel. In this experiment lettuce seed assays were used to compare ecotoxicity of a variety of concentration of methanol, ethanol and isopropanol. The reason lettuce seeds were used is because they have proven to be an easy and inexpensive means of testing the toxicity in water and sediments, including heavy metals, pesticides and other organic toxicants. E. (1992, April). Methanol. Retrieved from https://www.epa.gov/sites/production/files/2016-09/documents/methanol.pdf Environmental Impact - METHANOL INSTITUTE. (n.d.). Retrieved November 09, 2016, from http://www.methanol.org/environmental-impact/  Kwon, S. Y.; Levy, I. J.; Levy, M. R.; Sargent, D. V.; Tshudy, D. J.; Weaver, M. A. (2008)The dose makes the poison: Measuring ecotoxicity using a lettuce seed assay, Chemistry, Gordon College. Levy, Irv (10/24/16). Professor at Gordon College. Phone interview. The American Heritage dictionary of the English language (4th ed., Ser. 4). (2006). Boston, MA: Houghton Mifflin 12 Principles of Green Chemistry - American Chemical Society. (n.d.). Retrieved November 09, 2016,fromhttps://www.acs.org/content/acs/en/greenchemistry/what-is-green-chemistry/principles/12-principles-of-green-chemistry.html Alcohol Petri dish (control) (0%) (0.06%) (1.3%) (2.5%) (5%) (10%) Methanol 15 11 13 10 Ethanol Isopropanol 12 4 Mean root elongation for germinated seeds after five days Alcohol Petri dish (control) (0%) (0.06%) (1.3%) (2.5%) (5%) (10%) Methanol 1.95cm 1.62cm 1.26cm 0.4cm 0cm Ethanol 1.66cm 0.50cm Isopropanol 1.92cm 1.20cm 1.05cm