1 / 100

Whole Effluent Toxicity Basics

Whole Effluent Toxicity Basics. Betty Jane Boros-Russo NJDEP, Office of Quality Assurance Christopher J. Nally American Aquatic Testing. History. 16th century - scientists began testing the lethality of chemical compounds on animals prior to their use on humans for therapeutic purposes

salim
Download Presentation

Whole Effluent Toxicity Basics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Whole Effluent Toxicity Basics Betty Jane Boros-Russo NJDEP, Office of Quality Assurance Christopher J. Nally American Aquatic Testing

  2. History • 16th century - scientists began testing the lethality of chemical compounds on animals prior to their use on humans for therapeutic purposes • 1930’s - some of the first uses of aquatic organisms for testing to determine the causes of observed fish kills • 1945 - some of the first methods for conducting toxicity tests were published

  3. Use of Toxicity Testing in Water Quality Based Toxics Control • To characterize and measure the aggregate toxicity of an effluent or ambient waters • To measure compliance with whole effluent toxicity limits • As an investigative tool and to measure progress in a toxicity reduction program • As an ambient instream measure of toxicity to identify pollution sources

  4. NJ WET Program History • Early 1980’s - Acute monitoring and limits used on a routine basis • 1989 - Began use of chronic monitoring and chronic limits • 1993 - Group permit challenge on chronic WET • 1996 - Settlement and initial chronic WET program revisions • 1997 - Final program revisions adopted

  5. Test Species

  6. Species Selection • Sensitive species which are easily cultured and readily available year round • Must provide consistent and reproducible response • Also encourage ecologically, commercially and or recreationally important • No one species is always the most sensitive • Species used is dependent upon salinity of receiving water and the state standards

  7. New Jersey Freshwater Acute Test Species Invertebrates: (Daphnids) • Ceriodaphnia dubia • Daphnia magna • Daphnia pulex Fish • Pimephales promelas Fathead Minnow • Oncorhynchus mykiss Rainbow Trout • Salvelinus fontinalis Brook Trout

  8. Ceriodaphnia dubia • Female • approximately 2 mm Photo compliments of Marinco Bioassay Laboratory

  9. Pimephales promelas Photo by Karen McCabe from Animal Soup

  10. New Jersey Saline Acute Test Species Invertebrates: • Mysidopsis bahia Opossum Shrimp (Americamysis bahia) Fish • Cyprinodon variegatus Sheepshead Minnow • Menidia beryllina Inland Silversides • Menidia peninsulae Tidewater Silversides • Menidia menidia Atlantic Silversides

  11. Mysidopsis bahia Female approximately 6 mm in length Photo compliments of Marinco Bioassay Laboratory

  12. New Jersey Freshwater Chronic Test Species Invertebrates: • Ceriodaphnia dubia Fish • Pimephales promelas Fathead Minnow Algae • Selenastrum capricornutum

  13. New Jersey Saline Chronic Test Species Invertebrates: • Mysidopsis bahia Opossum Shrimp Fish • Cyprinodon variegatus Sheepshead Minnow • Menidia beryllina Inland Silversides • Menidia peninsulae Tidewater Silversides • Menidia menidia Atlantic Silversides Other • Arbacia punctulata Sea Urchin • Champia parvula Red Macroalgae

  14. Test Methods

  15. Rules for Conducting Toxicity Tests • 40 CFR 136.3 - Table 1A • Effective November 15, 1995 • Amended November 19, 2002 and effective December 19, 2002 • Methods must be followed as they are written

  16. Incorporate by Reference • Methods for Measuring the Acute Toxicity of Effluents to Freshwater and Marine Organisms. 5th Edition, USEPA, Office of Water, October 2002, EPA 821-R-02-012 • Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. 4th Edition, USEPA, Office of Water, October 2002, October 2002, EPA 821-R-02-013 • Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms. 3rd Edition. USEPA, Office of Water, October 2002, EPA 821-R-02-014

  17. USEPA Methods Documents • Health and safety • Quality assurance • Facilities, equipment and supplies • Test organisms and culture methods • Dilution water

  18. USEPA Methods Documents(cont.) • Effluent sampling and handling • Endpoints and data analysis • Individual test methods • Report preparation and test review

  19. Test Types • Acute and Short-term Chronic Tests • Static non-renewal • Static renewal • Flow through • Test Species dependent • Use dependent

  20. Test Design • 5 Concentrations + Control • Serial dilution’s of effluent and “control water” (also termed “dilution water”) • Dilution series of 0.5 or greater • Single concentration test • Replicates • Randomization (organisms/chambers)

  21. Perspective is Everything

  22. Test Conditions and Acceptability Criteria

  23. Acute Toxicity Tests • Test Procedures • 96 hours or less (species specific) • Mortality is the measured endpoint • For daphnia mortality determined by immobilization • Advantages • less expensive and time consuming than chronic • endpoint is easy to quantify • Disadvantages • indicates only lethal concentrations • only the effects of fast acting chemicals are exhibited

  24. Acute Test Acceptability Criteria • Minimum control survival at least 90% • Temperature maintained @ 20 +/- 1o C • Maximum test organism age at start: • 14 days for fish • 5 days for Mysid shrimp • 24 hours for daphnids

  25. Short-term Chronic Toxicity Tests • Test Procedures • typically 4-10 days • Mortality, growth, fecundity, reproduction • Advantages • more sensitive than acute, assess parameters other than lethality • may better reflect real world • Limitations • more costly and time intensive than acute • more sensitive to low level contamination

  26. Chronic Test Acceptability Criteria • Minimum control survival 80% • Minimum control dry weight (average): • 0.25 mg for fish • 0.20 mg for Mysid shrimp • Minimum of 15 young (average) for control C. dubia • Temperature maintained @ 25 +/- 1o C • Maximum test organism age at start: • 48 hours for fish • 7 days for Mysid shrimp • 24 hours for daphnids

  27. Method Specific Test Conditions • Test type and duration • Temperature, light, DO, salinity • Chamber size and volume • Species selection, age and feeding

  28. Method Specific Test Conditions (cont.) • Dilution water • Dilution series • Sampling • Test acceptability criteria • Test measurements

  29. Test Measurements • Dissolved oxygen cannot fall below 4 mg/l (initial and final) • pH (initial and final) • conductivity • total residual chlorine • total hardness and alkalinity • salinity • temperature

  30. Selection of Dilution Water • May be either a standard laboratory water or the receiving water • Choice of water is dependent on the objectives of the test • Absolute toxicity use standard water • Estimate of toxicity in uncontaminated receiving water, use receiving water • Contaminated receiving water, use laboratory water

  31. Data and Endpoints

  32. Acute Test Endpoints • LC50 - Concentration of effluent that is lethal to 50 percent of the exposed organisms at a specific time of observation (e.g. 96 hr LC50), (expressed as % effluent) • NOAEC - No Observed Adverse Effect Concentration • Lowest concentration at which survival is not significantly different from the control • always set equal to 100% effluent • EC - Effect Concentration

  33. Test Data • Typical dose response where mortality increases as the concentration of effluent in the mixture increases. • LC50 would be somewhere between 25% effluent and 50% effluent. 6.25 % Effluent 12.5 % Effluent 25.0% Effluent 50.0% Effluent 100.0% Effluent Control 0% Mortality 0% mortality 20 % Mortality 40% Mortality 80% Mortality 100% Mortality

  34. Chronic Test Endpoints • IC25 - Inhibition Concentration - Concentration of effluent which has an inhibitory effect on 25% of the test organisms for the monitored effect, as compared to the control (expressed as % effluent). • NOEC - No Observable Effect Concentration - Highest concentration of effluent tested which shows no statistically significant effect on the organisms as compared to the control (expressed as % effluent).

  35. Chronic Test Data % % Average EffluentMortalityDry weight% w/Eggs 0 2.5 0.418 69.6 6.25 7.5 0.371 68.8 12.5 10.0 0.348 50.0 25.0 10.0 0.308 28.6 50.0 17.5 0.248 0.0 100.0 100.0 0.0 0.0 NOEC 50.0% 12.5% 12.5% IC25 55.7% 23.2% 10.7%

  36. Toxicity Values • LC50, IC25, NOAEC: As a limit these values will INCREASE as the limit becomes more stringent • These are minimum limits • LC50, IC25: When evaluating data, exhibit more toxicity as the values decrease • Toxic Units: Maximum limits • As values increase as limits, they become less stringent

  37. Toxic Units (TU’s) • Reciprocal of the fractional LC50, NOEC, IC25 value • Calculated by dividing the value into 100 • TUa = 100/LC50 • TUc = 100/IC25

  38. Standard Reference ToxicantProgram

  39. Standard Reference Toxicants (SRT’s) • Purpose • Frequency • Acceptability Criteria • Control Charts

  40. Control Charts

  41. Sample Collection

  42. Subchapter 9 • N.J.A.C. 7:18 Subchapter 9 Sample Requirements • Addresses collection, handling and preservation of environmental samples • Section 9.5 – Requirements for acute toxicity testing samples

  43. Grab vs. Composite • Grab samples offer “snap shot” of effluent • Composite samples offer “average view” of effluent • NJDEP requires sampling based on discharge type • Continuous discharge – 24 hour composite sample • Intermittent discharge – grab or composite each day that is representative of discharge

  44. Frequency and Holding • Daily for acute toxicity testing (single comp. for daphnids) • Every 48 hours for chronic testing • Minimum # of samples for 24 hour composite - 48 (every 30 minutes) • Holding times • 24 hours to first use for acute and chronic testing • 72 hours to use three times, chronic testing only

  45. Effluent Sampling Containers • Constructed of non-toxic materials: • Glass – borosilicate, tempered or soda lime • 304 or 316 stainless steel • Medical or food grade silicone • Perfluorocarbons – Teflon, etc. • Plastics – polyethylene, polypropylene, polycarbonate,polystyrene • Containers rinsed with sample, used once and disposed of, or cleaned.

  46. Sampling Location • NJPDES sample location must be used for toxicity test sampling • This is generally the same sampling location required for all other parameters • Prechlorination sampling may be required • Post dechlorination sampling may be required • Location should always be specified in the permit

  47. Preservation • For toxicity testing only temperature preservation permitted • Refrigeration during sampling optional • Refrigeration or icing immediately upon collection required

  48. SAMPLING DOCUMENTATION • Chain of Custody • Facility information • Date, time, sample ID, sampler ID, sample location information • Signatures for custody transfer • Signatures are important!! • Avoids confusion • Prevents sampling from occurring when plant not operating normally

  49. New Jersey Toxicity Testing Program

  50. Whole Effluent Toxicity Approach to Water Quality Based Toxics Control • WET is used as an effluent parameter to measure the aggregate toxic effect of the discharge of toxic pollutants to surface waters • Goal is to protect aquatic biota and achieve surface water quality standards • Limits are set to be met at the “End of the pipe” to satisfy the “No toxics in toxic amounts” narrative water quality standard

More Related