Title: Microconstituents Emerging Contaminants
1Microconstituents Emerging Contaminants
- Joint Water Resources Symposium
- New York Water Environment Associations
- New York Section American Water Works Association
- In Honor or Edwin C. Tifft, Jr.
- Syracuse, NY
- November 14, 2007
- Joseph G. Cleary, P.E., BCEE
- Principal
- HydroQual, Inc.
- Mahwah, NJ
2Presentation Outline
- WEFs Community of Practice Activities
- Microconstituents - Whats Included?
- Terminology / Name Changes / Key Messages
- Treatment Technologies
- Approach to Develop Best Solution
- Case Studies
- Summary
3- WEF Community of Practice Activities
4Why are Microconstituents a Concern?
- Better analytical methods and more monitoring are
finding them in numerous receiving waters - Feminized fish discovered in Europe in mid 1990s
- Steroids are implicated in Europe in late 1990s
- Treatment studies on POTWs (2002-2003) show POTWs
are a collection point and one source to
receiving waters - USGS study of 139 streams in 2002 detected
pharmaceuticals in 80 of samples - More media coverage public awareness and
concerns.
5WEF Community of Practice (CoP)
- Began at WEFTEC 2005 in Washington DC
- Deals with hot topics
- Broad, diverse membership a benefit and
challenge - 150 Members and growing
6WEF Key Messages
- Committed to sharing clear, factual information
- Advancing understanding
- Pursuing sound, sustainable solutions
- Focusing on source control
7Two Fundamental Challenges
- Technical challenges due to scientific
uncertainties - Communication challenges related to public fears
and perceptions.
8WEF Community of Practice (CoP)
- Identified work products
- Technical Practice Updates
- Public Press Communications
- Glossary of Terms
- Name for the issue
9WEFs Public Communications Role
- Staff Products include
- Key Messages
- Fact Sheets
- Illustrations
- Finding Expert Spokespersons
- Building Consensus
10Varying Communication Challenges Include
What to call the compounds without negatively
branding them as a worry or concern? Media
accounts and technical publications already using
a multiplicity of terms
11Varying Communication Challenges Include
Scientists wanting to communicate with precision
to scientists WEF needs also to communicate with
the scientific community, its membership and the
general public The required vernacular must vary
to suit the audience so the language must be
tailored
12Communication Challenge
- Second challenge - Technical and communications
experts - Different audiences
- Different vocabulary
- Different approaches
13- Microconstituents - Whats Included?
14Micro Constituents in Water Where Do They Come
From?
Courtesy of CH2M Hill
15Reference Kobylinski, Hunter and Scruggs, 2005
16New Emerging Compounds
benzene, naphthalenesulfonates
HYDROPHILIC
surfactants
pharmaceuticalsbetablockers, antibiotics,
contrast media, analgesics, antiepileptics,
parasiticides, babiturates, opioides
perfluorinatedcompounds (PFOA)
corrosion inhibitorse.g. benzotriazole
POLARITY
NDMA
phosphoric ester flame retardants
estrogenes
MTBE
UV filter
from Walter Giger, in Ternes und Joss, IWA
Publishing, 2006
musk fragrances
Volatility
NON VOLATILE
LIPOPHILIC
VOLATILE
17New Emerging Compounds
conc. in µg/L
360000 Pop. Equiv. Nitrification/Denitrification
Ternes et al., Chemosphere 2007
18Diversity of Endocrine Disruptor Compounds
(Falconer (2003) and Wren (2001))
19Why are Microconstituents a Concern?
- A review by the World Health Organization has
concluded that low-level environmental exposure
to Endocrine Disruptors has not yet been
demonstrated to cause harm to human health
(Damstra et al., 2002). - Uptake of Endocrine Disruptors by humans from
treated drinking water is relatively low in
comparison to other sources such as food (GWRC,
2003).
20(No Transcript)
21- Terminology / Name Changes / Key Messages
22WEF Terminology Challenges
Nov 2005 Endocrine Disrupting Compounds
(EDC) (goal was communicating with WEF
membership) Feb 2006 Compounds of Emerging
Concern (CEC) (because not just about endocrine
issues) Oct 2006 Compounds of Potential
Concern (how to respond to the public diligence
in studying the issue)
23Terminology Challenge
May 2007 More discussion about alarming the
public when we dont have a basis to ring the
alarm bells Micro-constituents No, not little
voters but really small things in the water
environment that we can now detect (at ppb and
ppt) and we dont know enough about.
24WEF Key Messages
These compounds are referred to in a multiplicity
of ways including micro-constituents, trace
constituents compounds of emerging concern, etc.
WEF is calling them micro-constituents. We
continue to study them as a prudent, conservative
course of action reflecting our commitment to
continue to assess the potential impact on human
health and the environment.
25WEF Key Messages
Low levels of compounds remain but in
concentrations that we believe are safe to return
to the environment There are differing levels of
Wastewater Treatment and Water Treatment We are
studying the issue of even the trace amounts of
these chemicals that remain after wastewater
treatment
26WEF Key Messages
- Treated wastewater is not the only pathway for
these substances to enter the environment - Many items we can detect have beneficial effects
(i.e. medicines and pest control) - Some improvement quality longevity of life
27WEF Key Messages
- Effects depend on
- - Nature of compound
- - Type of exposure
- - Concentration
- - Quantity/duration of exposure
28Some Facts to Keep in Mind
- Some compounds are naturally occurring
- Society chooses to ingest, bathe in and apply
constituents at much higher concentrations than
ever found in the environment
29 30Physical/Chemical Properties Keys to Treatment
- Water Solubility (mg/L)
- Henrys Constant (atm m3/mole)
- Octonal Water Coefficient Log Kow (Partitioning
to Solids) - Vapor Pressure, Vp
- Distribution Coefficient, Kd
- Biotransformation Ratio (K bio in soil, water,
sludge and sediment) - Biodegradability
- Photolysis Rate
- Oxidation Rate
- Reduction Rate Reference
Williams, 2006
31Applicable Treatment Technologies for EDCs
- Aerobic Biological Treatment Processes including
Nitrogen Removal (e.g. Activated Sludge, Membrane
Bioreactors) - Chlorination (e.g. bleach, alkaline chlorination)
- Advanced Oxidation (UV/Peroxide, Ozone/Peroxide,
UV/Ozone - Carbon Adsorption
- Membrane Filtration and Reverse Osmosis
- Thermal Oxidizers
- Anaerobic Biological Treatment
32Summary of Poseidon Project in Europe (Thomas
Ternes)
- PPCPs and Estrogens removal focus in Europe
- Membranes Ozonation in combination with
Activated Sludge Biofilters were evaluated
- Sludge treatment and urine separation was
evaluated
- Sorption is an important mechanism for
hydrophobic and positively charged compounds
- Biodegradation is a key mechanism
- Stripping was not effective
- Chemical oxidation was an effective polishing
step for some PPCPs
- Some PPCPs are degraded in anaerobic sludge
digestion
- Available process models can be used using rate
- coefficients developed
33Activated Sludge
34Membrane Bioreactor Process
35Fixed Film Technology
36Other Treatment Studies
- MLE Plant in San Diego (WERF Study, Oppenheimer,
2005) - Six full-scale WWTPs in the U.S. and two pilot
scale MBRs (WERF Study, Oppenheimer, 2006) - Half of the 20 PPCPs were removed to greater than
80 at SRT lt5 days - No additional removal was attributed to MBR,
media filters or longer HRTs - Removal of musk fragrances required SRTs of at
least 25 days
37Results from Two-Stage MBR Ozone Treatment in
Pilot Study
- APIs concentrations are listed in ?g/L
- DL Detection limit
- ND Not detected
- Reference Helmig, Edward et al., WEFTEC 2005
38Ozone Treatment
Carbamazepine
Huber et al., 2003, Env.Sci.Technol.
39WEF Technical Practice Update on Treatment
- EDC Committee Formed _at_ WEFTEC October 2005
- List of TPUs was developed (? 13 topics)
- Treatment was done first
- Draft for comment in January 2006
- Review meeting in February 2006
- Committee name changed to Contaminants of
Emerging Concern now Microconstituents - Comments received in March 2006 on Treatment
White Paper Change to Technical Practice Update - Final draft April 2007
- Final version now on WEF website along with
others
40What Has Been Done and What Do We Know
- Many studies have demonstrated that activated
sludge processes have the potential to remove a
large fraction of several suspected EDCs, often
to below detection limits (Ying, 2002). - Johnson and Darton (2003) state that the EDCs
generally implicated in endocrine disruption in
fish the estrogens E1, E2, EE2, and NP are
all inherently biodegradable
41What Has Been Done and What Do We Know(continued)
- Siegrist estimates that about a 10 to 15 day SRT
would be required for appreciable EDC removal
(Siegrist et al., 2005). - Estrogens can be eliminated in WWTPs by applying
a nitrification/denitrification step (SRTs ?15
days), or by effluent ozonation, nanofiltraton,
or activated carbon. - Anaerobic sludge digestion leads to a degradation
of some PPCPs.
42What Has Been Done and What Do We Know(continued)
- Substances that are difficult to biodegrade may
be oxidized by AOPs, and the oxidized byproducts
may be more amenable to biodegradation (Ried and
Mielcke, 2003). - Advanced oxidation process (AOP) are combinations
of UV plus hydrogen peroxide, ozone plus hydrogen
peroxide, and UV plus ozone, that are
specifically designed to increase the formation
of powerful hydroxyl radicals to oxidize EDCs and
provide disinfection. Ozone shows similar
potential to the AOPs for EDC removal.
43What Has Been Done and What Do We Know(continued)
- 100 removal of EDCs from WWTP effluent will not
be possible, so the goal should be reduction to
levels with no adverse environmental effects. - Source control (e.g., ecolabelling) and source
separation (e.g., urine or rain water
segregation) are important measures for reducing
the PPCP load entering the environment.
44What is Needed or Not Known?
- Toxicological and other environmental impacts are
not known for most EDCs. - Risk assessment studies are needed to develop
appropriate regulatory actions (Schoenberg,
Helmig et al., 2005). - Fate studies are needed describing removals of
compounds and pathways biodegradation/biotransfor
mation, partitioning to solids, volatilization.
45What is Needed or Not Known?(continued)
- Analytical procedures are needed to detect lower
levels of estrogens and to distinguish between
various forms. - Research to better understand the performance of
engineered and natural treatment systems for
reduction of these compounds (Oppenheimer et al.,
2005). - The hazard potential of the byproducts formed
through treatment with advanced oxidation
requires additional investigation.
46- Integrated / Holistic Approach to Develop Best
Solution
47Urban Water Cycle
STP
48Integrated vs. End-of-Pipe Approach
49Collaborative TeamApproach is Best
- Mobilize a Team Include People Closest to
Problems and Stakeholders - Include Production, Water and Wastewater
Operations, Environmental Compliance Managers - Outside Consultant
- Commitment of Management and Team
- Frequent Communications and Meetings
50ApproachSequence of Tasks
- Flow Balance Wastewater Characteristics
- Design Basis (flow wasteloads)
- Screen Technologies
- Develop Initial Alternatives
- Alternative Comparison (cost non-costs
criteria) - Narrow List of Alternatives
- Treatability Studies Process Modeling
- Refine Comparison
- Select Best Solution
51 52Case Study 1
- Pharmaceutical Company in U.S.
- New Product from Europe Chlorination (bleach)
used for destruction - Initial testing showed it was non-biodegradable,
would pass through existing treatment plant and
result in effluent toxicity violations. - Treatability Studies were conducted to evaluate
Advanced Oxidation treatment technology
UV/hydrogen peroxide, catalyst/UV/hydrogen
peroxide, UV/ozone and UV/hydrogen
peroxide/ozone. - Two technologies also reduced effluent toxicity
by 95 (UV/ozone and UV/ozone/hydrogen peroxide. - Product was never brought to the plant from
Europe.
53Chemical Oxidation Technology Evaluation
54Case Study 2
- Pharmaceutical Company in Puerto Rico
- New Product
- Active Pharmaceutical Ingredients (API) in
cleaning wastewaters - Company had Corporate Guidelines (from Europe)
for discharge to the Atlantic Ocean - Discharge through POTW to Atlantic Ocean
- Best solution was holding tank with controlled
release to POTW no treatment was needed
55(No Transcript)
56Case Study 3
- Pharmaceutical Company in Ireland.
- Considering production of an antifungal compound.
- Compound is relatively insoluble and
non-biodegradable. - Potential to accumulate in sludge and impact
composting. - Concern was potential impact on activated sludge
plant and sludge composting at POTW. - Treatability Studies simulated activated sludge
and sludge composting to determine process
impacts and concentrations present in sludge and
compost material. - There was no impact on activated sludge
performance including nitrification. - Mass balance showed 70 of compound was
biodegradable. - There was no impact on composting process.
57Bench-Scale Anoxic and Aerobic Reactors
58SUMMARY
- Microconstituents are now being detected more in
water and wastewater.
- Analytical methods are specialized.
- Information is developing on treatment/destruction
of Microconstituents in both POTWs and
pharmaceutical wastewaters.
- Applicable treatment technologies include
biological and advanced oxidation processes.
- EDCs removal in POTWs and Industrial Wastewater
Plants varies based on wastewater characteristics
and process design operating parameters such as
sludge age.
- Treatability studies are very helpful for
site-specific wastewater projects.
- Stay tuned as more Technical Practice Updates
are developed by WEF and specially conferences
are planned.
59Thank you! QUESTIONS?