tools for addressing whole effluent toxicity 2013 asp annual conference n.
Skip this Video
Loading SlideShow in 5 Seconds..
TOOLS FOR ADDRESSING WHOLE EFFLUENT TOXICITY 2013 ASP ANNUAL CONFERENCE PowerPoint Presentation
Download Presentation
TOOLS FOR ADDRESSING WHOLE EFFLUENT TOXICITY 2013 ASP ANNUAL CONFERENCE

Loading in 2 Seconds...

  share
play fullscreen
1 / 35
Download Presentation

TOOLS FOR ADDRESSING WHOLE EFFLUENT TOXICITY 2013 ASP ANNUAL CONFERENCE - PowerPoint PPT Presentation

kenton
141 Views
Download Presentation

TOOLS FOR ADDRESSING WHOLE EFFLUENT TOXICITY 2013 ASP ANNUAL CONFERENCE

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. TOOLS FOR ADDRESSING WHOLE EFFLUENT TOXICITY 2013 ASP ANNUAL CONFERENCE Laura Shealy Davis Shealy Consulting, LLC 2013 ASP Annual Workshop

  2. TOPICS FOR DISCUSSION • Toxicity/TIE Basics • Toxicity Characterization Procedures • Case Studies/Knowledge Test Shealy Consulting, LLC

  3. PURPOSE OF WHOLE EFFLUENT TOXICITY DEFINITION Whole effluent toxicity (WET) is the aggregate toxic effect of an effluent sample measured directly by an aquatic toxicity test.

  4. PURPOSE OF WHOLE EFFLUENT TOXICITY EXPANDED DEFINITION WET tests utilize live organisms to measure actual biological responses to an effluent and, therefore, integrates the effects of all chemicals present in the effluent.

  5. PURPOSE OF WHOLE EFFLUENT TOXICITY Why Perform Toxicity Testing? Measuring all potentially toxic chemicals in a sample would not be feasible (>50 million in CAS registry) WET tests are performed in order to indirectly measure all potentially toxic chemicals present WET predicts the potential an effluent to have an adverse effect on the in-stream aquatic population

  6. Shealy Consulting, LLC

  7. Effluent Toxicity Complexity Factors Frequency Magnitude Persistence TOXICITY Antagonism Synergism # Toxicants TOXICITY COMPLEXITY FACTORS Several factors that effect the complexity of toxicity and make it more difficult to control Shealy Consulting, LLC

  8. TIE BASICS “TOOLBOX” APPROACH TO IDENTIFYING AND RESOLVING TOXICITY Data Acquisition Phase I, II, III Procedures Toxicity Source Elimination Toxicity Control Implementation Shealy Consulting, LLC

  9. DATA ACQUISITION • Historical effluent toxicity and analytical data • Operational and maintenance practices • Pretreatment data • Sometimes TIE’s can be completed with at this step Shealy Consulting, LLC

  10. PHASE I CHARACTERIZATION PROCEDURES ManipulationTarget Compounds Filtration Toxicants associated with particulates Aeration Toxicants that are volatile or can be oxidized C18 SPE Toxicants that are non-polar Oxidant Toxicants that can be reduced EDTA Toxicants that complex with EDTA Graduated pH Toxicants that are pH Dependent Filtration, aeration and C18 SPE are performed under neutral, basic and acidic pH conditions. Shealy Consulting, LLC

  11. PHASE II TOXICITY IDENTIFICATION PROCEDURES • Methanol Elution (non-polar organics) • Equitoxic Solution Test (ammonia) • Sublation (foam fractionation) • Various Chemical Analyses FOLLOW-UP TESTING ON SPECIFIC TOXICANTS Shealy Consulting, LLC

  12. PHASE III TOXICITY CONFIRMATION Shealy Consulting, LLC

  13. Science is a wonderful thing if one does not have to earn one's living at it. ~Albert Einstein Few TIE’s are “Text Book” Difficulty in identifying toxicity increases in direct proportion to the complexity of an effluent Shealy Consulting, LLC

  14. CHALLENGES WITH ORGANICS Some organics are toxic at levels below detection limits Some organics are hard to ID with instrumentation typically used by environmental labs (GC and GC/MS) >66,000,000 commercially available chemicals (CAS) Shealy Consulting, LLC

  15. “IMPOSSIBLE” TIE’S Sometimes conventional TIE methods are not appropriate because: • MULTIPLE COMPLEXITY FACTORS EXIST MARGINAL CHRONIC TOXICITY AND TOXICITY FREQUENCY • INADEQUATE INSTRUMENTATION TO ID ORGANICS • MULTIPLE TOXICANTS BY MULTIPLE SOURCES Shealy Consulting, LLC

  16. If traditional TIE methods do not work • ALTERNATE APPROACHES MAY HELP SUCH AS: • MOLECULAR SIEVES • PBO ADDITION • FTIR • HPLC • TEST IN STREAM WATER • MICROTOX • REFRACTORY TOXICITY ASSESSMENT TESTING • ELECTRON MICROSCOPY Shealy Consulting, LLC

  17. Shealy Consulting, LLC

  18. PHASE I CHARACTERIZATION PROCEDURES ManipulationTarget Compounds Filtration Toxicants associated with particulates Aeration Toxicants that are volatile or can be oxidized C18 SPE Toxicants that are non-polar Oxidant Toxicants that can be reduced EDTA Toxicants that complex with EDTA Graduated pH Toxicants that are pH Dependent Filtration, aeration and C18 SPE are performed under neutral, basic and acidic pH conditions. Shealy Consulting, LLC

  19. PHASE I – AERATION TEST TARGET COMPOUNDS Toxicants that are volatile or can be oxidized Example VOC’s, chlorine, sulfur compounds Shealy Consulting, LLC

  20. PHASE I – AERATION TEST ADD pH ADJUSTMENT Certain compounds volatilize at specific pH values. Example Ammonia volatilizes more readily at high pH Shealy Consulting, LLC

  21. PHASE I – FILTRATION TEST TARGET COMPOUNDS Toxicants Associated with Particulates Examples Metals and Surfactants Shealy Consulting, LLC

  22. PHASE I – FILTRATION TEST ADD pH ADJUSTMENT Ionic strength of solution affects the solubility of compounds Examples Precipitation of some metals at high pH Shealy Consulting, LLC

  23. PHASE I – C18 SPE TEST TARGET COMPOUNDS Organic Compounds that are non-polar A non-polar molecule is one that the electrons are distributed so they do not have an abundance of charges at the opposite sides. The charges all cancel out each other. Examples Surfactants, Benzene, pesticides Shealy Consulting, LLC

  24. PHASE I – C18 SPE TEST ADD pH ADJUSTMENT At extreme pH values, some compounds shift to a predominately un-ionized form and can be sorbed onto carbon-18. Shealy Consulting, LLC

  25. PHASE I – OXIDANT REDUCTION TEST TARGET COMPOUNDS Toxicants that can be reduced with sodium thiosulfate addition (Na2S2O3) Na2S2O3 can also complex with certain cationic metals Examples Chlorine, copper, silver Shealy Consulting, LLC

  26. PHASE I – EDTA TEST TARGET COMPOUNDS Compounds that bind with EDTA Example – Metals EDTA forms strong complexes with Cu, Zn, Pb and Ni EDTA forms weak complexes with Hg and Ag Shealy Consulting, LLC

  27. Phase I – GRADUATED pH TARGET COMPOUNDS Toxicants that are pH dependent Examples – Ammonia, metals Shealy Consulting, LLC

  28. Interpreting Phase I Data Must look at all test results. What if toxicity is removed with aeration and filtration? What if toxicity is removed with filtration and Carbon-18? Shealy Consulting, LLC

  29. CASE STUDIES CASE #1 Filtration @ pH11 reduces toxicity EDTA reduces toxicity No effect with Sodium thiosulfate High levels of copper, nickel and silver Shealy Consulting, LLC

  30. CASE #1 SOLUTION NICKEL

  31. CASE STUDIES CASE #2 Filtration @ pH11 reduces toxicity EDTA reduces toxicity slightly Sodium thiosulfate eliminates toxicity High levels of copper, nickel and silver Shealy Consulting, LLC

  32. CASE #2 SOLUTION SILVER Shealy Consulting, LLC

  33. CASE STUDIES CASE #3 Aeration @ pH11 reduces toxicity Filtration reduces toxicity Graduated pH test indicates increased toxicity with increased pH Shealy Consulting, LLC

  34. CASE #3 SOLUTION AMMONIA Shealy Consulting, LLC

  35. QUESTIONS? LAURA SHEALY OFFICE (803) 808-3113 lshealy@shealyconsulting.net