2 Biotechnology and the Environment Environment – describes everything that surrounds a particular organismOther organismsSoil, air, waterTemperature, humidity, radiation
3 Biotechnology and the Environment Environmental Biotechnology -the development, use and regulation ofbiological systems for remediation ofcontaminated environments (land, air,water), and for environment-friendlyprocesses.Bioremediation - the use ofmicroorganisms to remedyenvironmental problems
4 Biotechnology and the Environment What are the events that triggered the interest in environmental biotechnology?Rachel Carlson’s Silent Spring (DDT)Love CanalBurning of a RiverExxon Valdez in 1989
5 Biotechnology and the Environment What do they all have in common?The advent of the Industrial Revolutionincrease in products and wastepeople moved to the cityincrease in human population
6 Biotechnology and the Environment Regulations were passed:Resource Conservation and Recovery Act (1976)Must identify hazardous waste and establish standards for managing it properlyRequires companies that store, treat or dispose to have permits stating how the wastes are to be managedRecord of its travels: Chain of CustodyEPA initiates the Superfund Program (1980)Counteract careless and negligent practicesEnvironmental Genome ProjectStudy and understand the impacts of environmental chemicals on human diseases
7 Biotechnology and the Environment WasteSolid: landfills, combustion-including waste-to energy plants, recoveryslurries, compostingLiquid: septic: sewage treatment, deep-well injectionGas: fossil fuels, chlorofluorocarbonsHazardous –anything that can explode, catch fire, release toxic fumes, and particles or cause corrosion
8 Biotechnology and the Environment Garbage TestBanana PeelWood Scrap/SawdustWax PaperStyrofoam CupTin CanAluminum Soda CanPlastic CartonGlass Bottles0.5 Years4 Years5 Years20 Years100 Years500 Years>500 Years
9 There is no waste in Nature: From rocks and soil to plants and animals to air and water and back again:Recycled largely byMicrobes
10 Biogeochemical Cycles are a major part of the recycling process Carbon Cycle: The primary biogeochemical cycle organic cmpds CO2 and backNitrogen Cycle: proteins amino acids NH3NO2-NO3-NO2-N2ON2 NH3 etc_Sulfur Cycle: Just like the nitrogen cycle, numerous oxidation states. Modeled in the Winogradsky columnPhosphorous Cycle: Doesn’t cycle between numerous oxidation states only soluble and insoluble form
14 Phosphorus Cycle Sea simple Phosphates Phosphate rocks Phosphates too complexfor plants to absorbfrom the soilSea simplePhosphatesPhosphaterocksMicrobes Breakdowncomplex compounds
15 Biotechnology and the Environment Scientists learn from nature in the 1980’sThe concept of Gaia –the total world is a living organism and what nature makes nature can degrade (bioinfalibility); only man makes xenobiotic compoundsClean up pollution-short and long term solutions (cost, toxicity, time frame)Use compounds that are biodegradableProduce Energy and Materials in less destructive waysMonitor Environmental HealthIncrease Recovery of Minerals and Oil
16 Biotechnology and the Environment Bioremediation finds its placeCompanies begin to specialize in cleaning up toxic waste spills by using a mixture of bacteria and fungi because cleaning these spills usually requires the combined efforts of several strains.Biotechnologists begin engineering “super bugs” to clean up wastes.However, there are many microorganisms in nature that will degrade waste products.
17 Bioremediation Basics Naturally occurring marshes and wetlands have been doing the job!What Needs to be Cleaned UP?Everything!How do pollutants enter the environment?Runoff, leachates, airSO How bioremediation is used depends onwhat is contaminated? (locations)on the types of chemicals that need to be cleaned upthe concentration of the contaminants (amount and duration)
18 Bioremediation Basics Chemicals in the environmentSewage (by products of medicines and food we eat such as estrogen (birth control pills) and caffeine (coffee)Products around the house (perfumes, fertilizers, pesticides, medicines)IndustrialAgricultural
19 Bioremediation Basics Some are known to be potential carcinogens and mutagens
20 Bioremediation Basics Fundamentals of Cleanup ReactionsMicrobes can convert many chemicals into harmless compounds HOW?Aerobic or anaerobicallyBoth involve oxidation and reduction reactions
21 Bioremediation Basics Fundamentals of Cleanup ReactionsOxidation and Reduction ReactionsOxidation involves the removal of one or more electronsReduction involves the addition of one or more electronsOxidizing agents gain electrons and reducing agents lose electronsThe rxns are usually coupled and the paired rxns are known are redox reactions
23 Bioremediation Basics Aerobic and anaerobic biodegradationAerobicOxygen is reduced to water and the organic molecules (e.g. petroleum, sugar) are oxidizedAnaerobicAn inorganic compound is reduced and the organic molecules are oxidized (e.g. nitrate is reduced and sugar is oxidized)NOTE: Many microbes can do both aerobic and anaerobic respiration; the process which produces the most ATP is used first!
24 Bioremediation Basics The Players: Metabolizing MicrobesSite usually contains a variety of microbesClosest to the contaminant: anaerobesFarthest away: aerobesThe most common and effective bacteria are the indigenous microbes (e.g. Pseudomonas in soil)Fungus and algae are also present in the environment and do a good job of “cleaning up” chemicals (fungi do it better than bacteria)
25 Bioremediation Basics Bioremediation Genomics ProgramsStimulating BioremediationAdd fertilizers (nutrient enrichment) to stimulate thegrowth of indigenous microorganismsAdding bacteria or fungus to assist indigenousmicrobes is known as bioaugumentation or seeding
26 Bioremediation Basics PhytomediationUtilizing plants to clean up chemicalsEx: cottonwoods, poplar, juniper trees, grasses, alfalfaLow cost, low maintenance and it adds beauty to the site
27 Cleanup Sites and Strategies Do the chemicals pose a fire or explosive hazard?Do the chemicals pose a threat to human health including the health of clean-up workers? (what happened at Chernobyl to the workers?)Was the chemical released into the environment through a single incident or was there long-term leakage from a storage container?Where did the contamination occur?Is the contaminated area at the surface of the soil? Below ground? Does it affect water?How large is the contaminated area?
28 Cleanup Sites and Strategies Soil CleanupEither remove it (ex situ bioremediation) or in situ (in place)In place:If aerobic may require bioventingMost effective in sandy soilsRemoved:Slurry-phase, solid phase, composting, landfarming, biopiles
29 Cleanup Sites and Strategies Bioremediation of WaterWastewater treatment
30 Cleanup Sites and Strategies Bioremediation of WaterGroundwater Cleanup
31 Environmental Diagnostics A promising new area of research involves using living organisms to detect and assess harmful levels of toxic chemicals.
32 Environmental Diagnostics Daphnia magnaTransparent Thorax and Abdomen
33 Environmental Diagnostics When healthy Daphnia are fed a sugar substrate (-galactoside attached to a fluorescent marker), they metabolize the sugar and fluoresce under UV light.Environmental DiagnosticsWhen Daphnia are stressed by toxins, they do not have the enzymatic ability to digest the sugar and therefore do not fluoresce under UV light.
34 Environmental Diagnostics Toxicity reduction involves adding chemicals to hazardous waste in order to diminish the toxicity.For example, if the toxicity results from heavy metals, EDTA will be added to the waste and the effluent will be tested again to determine if the toxicity has been acceptably reduced.EDTA chelates (binds to) metals, thereby making them unavailable to harm organisms in a particular body of water.
35 Applying Genetically Engineered Strains to Clean Up the Enviroment Petroleum eating bacteriaAnanda Chakrabarty at General ElectricHeavy metals (bioaccumulation)Bacteria sequester heavy and radioactive metalsBiosensorslux genes
36 Environmental Disasters: Case Studies in Bioremediation The Exxon Valdez Oil SpillIn the end, the indigenous microbes did the best jobOil Fields of KuwaitPoses a problem due to the environmental conditions
37 Future Strategies and Challenges for Bioremediation Microbial geneticsNew types of microbes (from the ocean etc)Radioactive materialsDO A BETTER JOB OF DETERMINING RISK and ASSESSMENT OF EXISTING SITES
38 Careers in Environmental Biotech BiodegradationWastewater treatment plants, organic farmingBioremediationEnvironmental clean-up companies, labs developing super bugsBiocatalysisPlastics, degradable and recyclable productsOtherMining companies, oil companies