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Specific Identification of Organic Pollutants in the Catawba Watershed Wastewater Treatment Plant Effluents. John Turner Faculty Mentor: Dr. Pat Owens Faculty Committee Members: Dr. Pat Owens, Dr. Cliff Calloway, Dr. Peter Phillips.
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Specific Identification of Organic Pollutants in the Catawba WatershedWastewater Treatment Plant Effluents John Turner Faculty Mentor: Dr. Pat Owens Faculty Committee Members: Dr. Pat Owens, Dr. Cliff Calloway, Dr. Peter Phillips
Many are toxic (harmful), carcinogenic (cancer-causing), or mutagenic (capable of altering genetic material) at very low levels Many organics have been shown to be endocrine disruptors capable of altering the sex of fishes May have the capability for bioaccumulation in the fat cells and membranes Threats posed by organics
Presently there is no testing of organic levels in WWTP effluents within the Catawba watershed Furthermore, testing of drinking water and river water for organics is not being done. Some organics such as 1,4-dioxane have been known to travel as far as 200 kilometers from its point of entry in a watershed. (Draper et al, 2000) The Status Quo
Research Design and Methods • Collection of WWTP samples • Bottle washing procedure • Glass bottles (approximately 600 mL) were used with glass stoppers • 2 mL HPLC grade Methanol added to each bottle • Stoppers returned to bottle and rolled and flipped so that Methanol completely covered the inside of the bottle • This was then repeated using reagent grade Ethyl Acetate • Unstopped bottles were placed in a dry oven at 108oC for 24 hours
Research Design and Methods • Collection of WWTP samples • Samples were collected from 2 WWTPs • Samples were collected from Rock Hill (Manchester Creek) and Fort Mill WWTPs. • The samples that were collected were composite samples
WWTP Locations • Rock Hill WWTP (Manchester) • Fort Mill WWTP
Research Design and Methods • Organic Extraction • The Basic Apparatus Glass Funnel Membrane Filter Vacuum Hose Erlenmeyer Vacuum Flask
Research Design and Methods • Organic Extraction • Empore C18 Membrane Filter Preparation • An Empore C18 Membrane Filter was placed at the bottom of the Glass Funnel on the screen. • 25 grams of Empore Filter Aid glass beads were added to the funnel • The disk was washed with 20 mL of elution solvent (methanol or ethyl acetate) and then allowed to dry • 20 mL of methanol was used to condition the disk
Research Design and Methods • Organic Extraction • Concentration of Organics onto the filter • The sample was decanted into the glass funnel. • The vacuum was then applied and the sample was allowed to run through the disk. • The vacuum was allowed to continue to run for 5-20 minutes so that residual water was removed.
Research Design and Methods • Organic Extraction • Organic Elution • The organics were eluted from the disk into an organic phase, and they were collected by placing a Kuderna-Danish flask under the membrane filter. • 10 mL of elution solvent was then added (either methanol or ethyl acetate) so that it covered the disk completely • The vacuum was used to pull the solvent that now contains the organics into the Kuderna-Danish flask.
Research Design and Methods • Organic Extraction • Concentration of Elution • Once the organics were concentrated into 10 mL of solvent they were further concentrated for analysis. • Two mL of elution solvent was removed. • Then the remaining 8 mL of elution solvent was evaporated down to approximately 1 mL. • This was done by blowing a gentle stream of nitrogen that passed through an organic carbon filter over the solvent.
Research Design and Methods • Organic Extraction • Analytical Plan 500 mL of Water 10 mL of extract 1 μL analyzed 1/50th 1/500th 1 mL of extract 1 μL analyzed
Research Design and Methods • Run Gas Chromatography-Mass Spectrometry • 1 μl of extract was injected into the GC column • The extract contains a mixture of the organics that were originally found in the wastewater but have now been concentrated into an organic phase. • The GC column separated the analytes based upon their polarity. • The MS measured the molecular weight of the various ions and a chromatogram was produced.
Results • Siloxanes • Phenol • Phthalates
Siloxanes – D5 • Rock Hill WWTP • 8.044 min with Ethyl Acetate • 8.043 min with Methanol
Siloxanes – D6 (cyclohexasiloxane) • Rock Hill WWTP • 11.915 min with Ethyl Acetate
Library Match for D6 Loss of 88
Siloxanes – D7(cycloheptasiloxante) • Rock Hill WWTP • 16.512 min with Ethyl Acetate
Siloxanes – D8 (cyclooctasiloxane) • Rock Hill WWTP • 21.165 min with Ethyl Acetate
Siloxanes – D9 (cyclononasiloxane) • Rock Hill WWTP • 25.317 & 35.826 min with Ethyl Acetate
Siloxanes – D10 (cyclododecasiloxane) • Rock Hill • 29.171, 32.651, 38.769, 41.553, 44.177, 46.642, 48.208, and 49.746 min with Ethyl Acetate • 15.744 min with Methanol • Fort Mill • 37.174 and 42.471min with Ethyl Acetate • 45.103 min with Methanol
Risks Associated with Siloxanes • Bioaccumulation in tissues and organs • Capable of inhibiting estrogen, leading to reproductive problems
Phenol • Rock Hill WWTP • 17.699 min with Ethyl Acetate • 17.672 min with Methanol
Risks Associated with Phenol • Most affects are related to the exposure to large quantities over time • Probably not a major problem unless found in substantial quantities
Bis (2-ethylhexyl) phthalate • Rock Hill WWTP • 42.699 min with Methanol • Fort Mill • 42.726 min with Methanol
Risks Associated withBis (2-ethylhexyl) phthalate • Has been shown to bioaccumulate in tissue • Affects the abilities of males to father babies
Conclusions • GC-MS was shown to be an effective means of identifying organics in wastewater • Within the organics identified, the siloxanes and phthalates have serious health effects at very low levels • This research established a basic understanding of the use of GC-MS in identifying organics in wastewater and has accumulated information to fuel further research in this area in the future at Winthrop
