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CE 3231 - Introduction to Environmental Engineering and Science

CE 3231 - Introduction to Environmental Engineering and Science. Readings for This Class:. O hio N orthern U niversity. Chemistry, Microbiology & Material Balance. Introduction. Water & Air Pollution. Env Risk Management. Partition Coefficients and Modeling

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CE 3231 - Introduction to Environmental Engineering and Science

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  1. CE 3231 - Introduction to Environmental Engineering and Science Readings for This Class: Ohio Northern University Chemistry, Microbiology & Material Balance Introduction Water & Air Pollution Env Risk Management Partition Coefficients and Modeling Real data characterizing risk is difficult and expensive to come across. As thousands of chemicals enter the market place each year, models help estimate the risk based upon compound structure and physical-chemical properties. Here, we examine how partition coefficients are used to make decisions.

  2. Exposure Assessment pathways of exposure calculating CDI

  3. Lecture 32Partition Coefficents and Modeling Risk(Risk III)

  4. Risk & Risk Assessment Topics Covered Include: New Chemicals Review Risk Models Partitioning Coefficients Octanol water Vapor pressure

  5. New Chemicals Review Program – Premanufacture Notice US Environmental Protection Agency Office of Pollution Prevention and Toxics Toxic Substance Control Act – Section 5 Program Goal Serve as a “gatekeeper to help manage the potential risk from chemicals new to the marketplace.” New Chemicals Review Program

  6. Risk Evaluations Risk Based - potential health risks - toxicological investigations Exposure Based - potential exposure risks - chemical property investigations - fate modeling: ranks outcomes I to IV New Chemicals Review Program

  7. Physical/Chemical Properties Boiling Point Melting Point Vapor Pressure Estimate Henry’s Law Constant Water Solubility (estimate) Octanol/Water Partition Coefficient (Kow, P) Soil/Sorption Coefficent (Koc) (estimate) Estimate Concentration in Air Estimate Concentration in Water Estimate Absorption through skin, lungs and GI Estimate Bioconcentration Estimate Migration through Soil to Groundwater Estimate Inhalation Exposure Estimate Removal in Wastewater Treatment Estimate Volatilization from water Estimate Toxicity Estimate Risk to Human Health and the Environment New Chemicals Review Program

  8. CAS Number : 000105-55-5Chem Name : n-boulanger Mol Formula: StRuCtUrEMol Weight : 186Melting Pt : -10 deg CBoiling Pt : 128 deg CWater Solubility: Value : 0.01 mg/L Temp : 37 deg C Type : EXPLog Kow (logP): Value : 3.57 Type : EXP Vapor Pressure: Value : 210 mm Hg Temp : 25 deg C Type : EXPHenry's Law Constant: Value : 6.85E-004 atm-m3/mole Temp : 25 deg C Type : EST Illustrating Example N-boulanger is used to formulate air fresheners.

  9. Octanol/Water Partitioning • Reported as log Kow or log P • Used to estimate water solubility, soil sediment adsorption, biological absorption (dermal, oral, GI, inhalation), bioaccumulation, and toxicity • model for partitioning within body New Chemicals Review Program

  10. Octanol/Water Partitioning 80% of PMN process is determined through use of log Kow - fuels QSARs (Quantitative Structural Activity Relationships) or EPA’s ECOSAR (Ecological Structural Activity Relationship) used during the evaluation • Experimental Determination • Shake Flask Method • Slow Stir • Generator Column via HPLC New Chemicals Review Program

  11. Octanol/Water Partitioning • Non-experimental Estimation Methods • Fragment/segment summation • Correlations with molecular descriptors (shape, volume,…) with known chemistries • Correlations with Reversed Phase HPLC Retention Times of known chemistries • 3 dimensional structure New Chemicals Review Program

  12. The Agency prefers experimentally derived Kow values. Whenever non-experimental methods will be estimated, the most conservative value will be used! Log Kow drives partitioning between the substance and biological tissues New Chemicals Review Program

  13. Vapor Pressure • rate of vapor condensation = vaporization rate of liquid • determined experimentally through automated instruments, an isoteniscope, or gas saturation procedure • strongly hints at air fraction • can be correlated for most compounds New Chemicals Review Program

  14. Vapor Pressure drives partitioning of compound between atmosphere. New Chemicals Review Program

  15. CAS Number : 000105-55-5Chem Name : n-boulanger Mol Formula: StRuCtUrEMol Weight : 186Melting Pt : -10 deg CBoiling Pt : 128 deg CWater Solubility: Value : 0.01 mg/L Temp : 37 deg C Type : EXPLog Kow: Value : 3.57 Type : EXP Vapor Pressure: Value : 210 mm Hg Temp : 25 deg C Type : EXPHenry's Law Constant: Value : 6.85E-004 atm-m3/mole Temp : 25 deg C Type : EST Putting Values into Context N-boulanger is used to formulate air fresheners.

  16. Putting Numbers into Context logPconsidered a problem when logKow > 5 (will bioaccumulate) logPfrom 2 to 5 considered likely to bioaccumulate logPfrom 0 to 2 potential to bioaccumulate

  17. Putting Values into Context CAS Number : 000105-55-5Chem Name : n-boulanger Mol Formula: StRuCtUrEMol Weight : 186Melting Pt : -60 deg CBoiling Pt : 128 deg CWater Solubility: Value : 0.01 mg/L Temp : 37 deg C Type : EXPLog Kow: Value : 3.57 Type : EXP Vapor Pressure: Value : 210 mm Hg Temp : 25 deg C Type : EXPHenry's Law Constant: Value : 6.85E-004 atm-m3/mole Temp : 25 deg C Type : EST

  18. CAS Number : 000105-55-5Chem Name : n-boulanger Mol Formula: StRuCtUrEMol Weight : 186Melting Pt : -60 deg CBoiling Pt : 128 deg CWater Solubility: Value : 0.01 mg/L Temp : 37 deg C Type : EXPLog Kow: Value : 3.57 Type : EXP Vapor Pressure: Value : 210 mm Hg Temp : 25 deg C Type : EXPHenry's Law Constant: Value : 6.85E-004 atm-m3/mole Temp : 25 deg C Type : EST Putting Values into Context logKow considered a problem when logKow > 5 (will bioaccumulate) logKow from 2 to 5 considered likely to bioaccumulate logKow from 0 to 2 potential to bioaccumulate

  19. CAS Number : 000105-55-5Chem Name : n-boulanger Mol Formula: StRuCtUrEMol Weight : 186Melting Pt : -60 deg CBoiling Pt : 128 deg CWater Solubility: Value : 0.01 mg/L Temp : 37 deg C Type : EXPLog Kow: Value : 3.57 Type : EXP Vapor Pressure: Value : 210 mm Hg Temp : 25 deg C Type : EXPHenry's Law Constant: Value : 6.85E-004 atm-m3/mole Temp : 25 deg C Type : EST Putting Values into Context

  20. CAS Number : 000105-55-5Chem Name : n-boulanger Mol Formula: StRuCtUrEMol Weight : 186Melting Pt : -60 deg CBoiling Pt : 128 deg CWater Solubility: Value : 0.01 mg/L Temp : 37 deg C Type : EXPLog Kow: Value : 3.57 Type : EXP Vapor Pressure: Value : 210 mm Hg Temp : 25 deg C Type : EXPHenry's Law Constant: Value : 6.85E-004 atm-m3/mole Temp : 25 deg C Type : EST Putting Values into Context

  21. Putting Values into Context CAS Number : 000105-55-5Chem Name : n-boulanger Mol Formula: StRuCtUrEMol Weight : 186Melting Pt : -60 deg C LIQUIDBoiling Pt : 128 deg CWater Solubility: Value : 0.01 mg/L LOW SOLUBILITY Temp : 37 deg C Type : EXPLog Kow: Value : 3.57 LIKELY TO BIOACCUMULATE Type : EXP Vapor Pressure: Value : 210 mm Hg VERY HIGHLY VOLATILE Temp : 25 deg C Type : EXPHenry's Law Constant: Value : 6.85E-004 atm-m3/mole Temp : 25 deg C MODERATELY VOLATILE Type : EST

  22. Fate considers reactions too! • Biologically mediated degradation • Hydrolysis • Photolysis (direct or indirect) All the models EPA uses to determine reactions are based upon the physical/chemical parameters reported in the PMN New Chemicals Review Program

  23. Putting Numbers into Context logPconsidered a problem when logKow > 5 (will bioaccumulate) logPfrom 2 to 5 considered likely to bioaccumulate logPfrom 0 to 2 potential to bioaccumulate

  24. New Chemicals Process • Gatekeeper for new chemicals • Dependent upon partitioning • Physical/chemical properties key • Modeling approach “…we’re busy alright. I can send you home with about 500 submissions right now. Do you have a U-Haul?...” New Chemicals Review Program

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