Microconstituents of Concern in Wastewater Treatment

Size: px

Start display at page:

Download "Microconstituents of Concern in Wastewater Treatment"

Gerald Dalton
5 years ago
Views:

1 Microconstituents of Concern in Wastewater Treatment Allen Gelderloos, PE. Associate Malcolm Pirnie, Inc Michigan Water Environment Federation Annual Conference June 24, 2009 INDEPENDENT ENVIRONMENTAL ENGINEERS, SCIENTISTS AND CONSULTANTS

2 Presentation Outline Background What are Microconstituents Occurrence in Water Environment Human Health Effects Fate of Microconstituents Knowledge Gaps Closing Remarks

3 Presentation Outline Background What are Microconstituents Occurrence in Water Environment Human Health Effects Fate of Microconstituents Knowledge Gaps Closing Remarks

4 The Wake Up Call

5 What's in a Name? Endocrine Disrupting Compounds (EDC) Compounds of Emerging Concern (CEC) Compounds of Potential Concern (CPC) Issue: Alarming the public when we don t have a basis to ring the alarm bells Present WEF terminology: Microconstituents Present in small amounts that we can now detect (ppb and ppt) and we don t know enough about.

6 The Headlines Male Fish Growing Eggs Found in Potomac SHARPSBURG, MD, Dec 20, 2004 (ABC News) Prozac seeping into water supplies UK, Aug 9, 2004 (The Scotsman) Mutant fish found in Colorado rivers EAGLE, CO, November 11, 2004 (Vail Daily)

The Chemical Universe A Quantitative Perspective 26 million organic and inorganic compounds 9 million are commercially available < 250,000 inventoried or regulated Chemicals that can

8 The Chemical Universe A Quantitative Perspective 26 million organic and inorganic compounds 9 million are commercially available < 250,000 inventoried or regulated Chemicals that can potentially be synthesized from existing stock: In reality around 1,000 new synthetic chemicals are produced annually About 20% of medication disposed of in sewer system unused

The Chemical Universe A Quantitative Perspective 26 million organic and inorganic compounds 9 million are commercially available We live in a chemical universe < 250,000 inventoried or regulated and

9 The Chemical Universe A Quantitative Perspective 26 million organic and inorganic compounds 9 million are commercially available We live in a chemical universe < 250,000 inventoried or regulated and need to come to terms with Chemicals that can potentially be synthesized from existing the consequences. stock: 1060 In reality around 3,000 new synthetic chemicals are produced annually About 20% of medication disposed of in sewer system unused

10 How Do Microconstituents End Up in Water Supplies? Wastewater (point source) discharges WWTP are collection points of MCs WWTPs not specifically designed to remove MCs Nonpoint source discharge Potentially a bigger problem BMPs have not been demonstrated to be effective in controlling MCs Animal waste likely to contain higher concentrations of MCs

11 Presentation Outline Background What are Microconstituents Occurrence in Water Environment Human Health Effects Fate of Microconstituents Knowledge Gaps Closing Remarks

12 Microconstituents Include a Range of Compounds that Provide Quality of Life Benefits Synthetic and naturally occurring hormones Flame retardants Antimicrobials, soaps, shampoos, fragrances Pharmaceutical drugs Cosmetics and nanotechnology material Bug repellents, pesticides, and herbicides Industrial chemicals Metals and plastics

Microconstituents Include a Range of Compounds that Provide Quality of Life Benefits Synthetic and naturally occurring hormones Flame retardants Antimicrobials, soaps, shampoos, fragrances

13 Microconstituents Include a Range of Compounds that Provide Quality of Life Benefits Synthetic and naturally occurring hormones Flame retardants Antimicrobials, soaps, shampoos, fragrances Pharmaceutical Many of drugs these compounds Cosmetics improve and nanotechnology & extend our lives material Bug repellents, pesticides, and herbicides Industrial chemicals Metals and plastics

Microconstituents Include Two Broad Subgroups Endocrine Disrupting Compounds (EDCs) Pesticides Steroids Metals Pharmaceuticals and Personal

14 Microconstituents Include Two Broad Subgroups Endocrine Disrupting Compounds (EDCs) Pesticides Steroids Metals Pharmaceuticals and Personal Care Products (PPCPs) Antibiotics Synthetic musks Sunscreens Surfactants/detergents Average adult uses 9 PCPs with 126 unique chemical ingredients

Why are Microconstituents a Not new. Have always been there. Recent Concern? Improved analytical techniques are allowing us to measure low concentrations How low is low?

15 Why are Microconstituents a Not new. Have always been there. Recent Concern? Improved analytical techniques are allowing us to measure low concentrations How low is low? Parts per million (ppm) 1 inch in 16 miles 1 cent in $10,000 Parts per billion (ppb) One drop of ink in 500 barrels of water One pinch of salt in 10 tons of potato chips Parts per trillion (ppt) One drop of ink in 500,000 barrels of water

16 Putting it in Proper Perspective The highest concentration of pharmaceuticals measured in drinking water represents: 0.5 inch in the distance between the earth & moon One second in 750 years

17 Presentation Outline Background What are Microconstituents Occurrence in Water Environment Human Health Effects Fate of Microconstituents Knowledge Gaps Closing Remarks

18 Occurrence of Microconstituents USGS Study (2002) 139 stream sites across 30 states 95 organic wastewater contaminants were measured 80% of streams contained contaminants Detection Frequency: Erythromycin: 22% Codein: 11% Acetominophen: 24% Caffeine: 71% Bisphonol A: 41% Tricolosan: 58% Environ. Sci. Technol., 2002, 36,

19 Occurrence of Microconstituents AP Investigation, March 10, 2008 pharmaceuticals, including antibotics, anticonvulsants, mood stabilizers and sex hormones, have been found in the drinking water supplies of at least 41 million US residents. Yet authorities fail to tell the public. The concentrations of these pharmaceuticals are small, measured in quantities of parts per billion or trillion. They fall far below the levels of a medical dose, but still, some scientists are concerned that the presence of so many prescription drugs may have long-term consequences.

20 But.. Detection is only one issue we have already mastered this What is lacking is knowledge regarding human health effect Both are crucial for establishing meaningful treatment goals

21 Presentation Outline Background What are Microconstituents Occurrence in Water Enviroment Human Health Effects Fate of Microconstituents Knowledge Gaps Closing Remarks

22 First Signs of Endocrine Disruption Male Fathead Minnow Male Fathead Minnow w/female Characteristics Female Fathead Minnow

23 Recent AwwaRF Study* Investigated 62 commonly-occurring compounds Trace amounts of 24 compounds found in at least 20% of raw water intakes Trace amounts of 11 compounds found in at least 20% of finished water Concentrations too low to cause health impact None was greater than its Acceptable Daily Intake (ADI) * Toxicological Relevance of EDCs & Pharmaceuticals in Drinking Water (2008)

24 What Do We Really Know Some fish near some WWTPs have been impacted by compounds mimicking the female hormone estrogen. To date, no studies have effectively linked wastewater EDCs to adverse health effects in humans. But impossible to prove a negative association

25 Presentation Outline Background What are Microconstituents Occurrence in Water Environment Human Health Effects Fate of Microconstituents Knowledge Gaps Closing Remarks

26 Fate of Microconstituents During Treatment Screening Primary Clarifier Aeration Basin Biodegradation Final Clarifier Residual Microconstituents RAS Primary Sludge Waste Activated Sludge

Factors Impacting Biodegradation/Adsorption Biodiversity Biodiversity Function of solids retention time (age) Increases BOD removal: 2-4 days (aeration) Nitrification: 8-12 days (aeration) Nutrient

27 Factors Impacting Biodegradation/Adsorption Biodiversity Biodiversity Function of solids retention time (age) Increases BOD removal: 2-4 days (aeration) Nitrification: 8-12 days (aeration) Nutrient removal: days (total) Fraction of active biomass in MLSS Number of bugs More bugs, greater degradation Floc size Impacts adsorption Temperature Higher temp. higher biodegradation rate PPCP Removal Increases

28 Increasing Adsorption Microconstituent Interactions In Biological Process Tetracycline X X Triclosan X Carbamazepine X Caffeine Increasing Biodegradability A. Thompson, et al. (2004)

29 Other Treatment Processes NF membrane & RO provide significant removals Free 3 mg/l in drinking water Steroids, Triclosan (>80% removal) Chloramines less effective than free chlorine Ozone more effective than free chlorine O 3 + H 2 O 2 provides marginal increase in removals UV light ineffective at typical disinfection doses More effective at significantly increased dose & when combined with H 2 O 2 GAC & PAC highly efficient

30 Energy & Materials Life Cycle Analysis Holistic Approach to Achieve Net Positive Impact Simple Process Modest MC removal Complex Process Wastes & Emissions Significant MC removal

31 Presentation Outline Background What are Microconstituents Occurrence in Water Environment Human Health Effects Fate of Microconstituents Knowledge Gaps Closing Remarks

32 Knowledge Gaps Health risks Synergistic effects Fate during treatment and sludge disposal Formation of harmful intermediaries Cost: Source control versus removal at WWTP versus removal at water plant

33 Presentation Outline Background What are Microconstituents Occurrence in Water Environment Human Health Effects Fate of Microconstituents Knowledge Gaps Closing Remarks

34 Summary MCs are not new. Just because we can detect MCs at very low levels does not mean they are harmful To date, no MCs have been directly implicated with human health We use MCs at much greater concentrations Caffeine in 1 cup of coffee (20 oz) water Caffeine in 5 million bottles The highest amount of pharmaceuticals detected in our drinking waters is about 5 million times lower than the therapeutic dose

35 Summary WWTP are not designed to remove MCs. But, Many MCs are removed to a significant extent Fate during biosolids processing & disposal not well understood Active research is underway to bridge knowledge gaps

36 Summary No need to panic. But plan judiciously. Sustainability should be at the core of all decision making Use Life cycle analysis to achieve net environmental benefit Stay informed. Interact with regulators & advocate rulemaking based on solid science. Educate the public including the next generation Promote community action ( No Drug Down the Drain ) Encourage/support research focused on determining health effects

37 Questions?

Pharmaceuticals and Personal Care Products in Drinking Water

Pharmaceuticals and Personal Care Products in Drinking Water Pharmaceuticals and Personal Care Products in Drinking Water Scientific advances in pharmaceutical therapies and the growing availability of