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THE EMERGING FOCUS OF PHARMACEUTICALS IN WATER ENVIROPHARM 2010 October 7, 2010 Ed McBean, Ph.D., P.Eng. (University of Guelph) Gary Lagos, P.Geo. (Conestoga-Rovers & Associates). AGENDA. Background Sources/Transport of Pharmaceuticals in the Environment Regulatory Framework
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THE EMERGING FOCUS OF PHARMACEUTICALS IN WATER ENVIROPHARM 2010 October 7, 2010 Ed McBean, Ph.D., P.Eng. (University of Guelph) Gary Lagos, P.Geo. (Conestoga-Rovers & Associates)
AGENDA • Background • Sources/Transport of Pharmaceuticals in the Environment • Regulatory Framework • Current Canadian Research • Future Research and Challenges • Discussion
BACKGROUND SUMMARY Recent occurrence of pharmaceuticals in surface and groundwater at measurable but very low concentrations (USGS 2002 study) What are the implications? Last 10 years significant amount of research within scientific community Research based on scientific principles Interdisciplinary group of water scientists (Centre for Control of Emerging Contaminants-CCEC)
BACKGROUND SUMMARY Thousands of chemical substances! COMMONLY DETECTED AND STUDIED PHARMACEUTICALS: Anti-inflammatory drugs (Tylenol, Advil, Motrin) Lipid regulators (Biston) Beta-blockers (Lopressors) Antidepressants (Prozac) Muscle relaxants (Valium) Estrogens (Oral Contraceptive) Antibiotics Chemicals used in our society to extend lifespan and improve quality of life!!
SOURCES/TRANSPORT TYPICAL ROUTES Human medication- ingestion/excretion (normally in urine) Unused pharmaceuticals directly flushed down the toilet Veterinary medication-consumption/excretion/land application Municipal wastewater treatment plants Industrial wastewater treatment plants Landfills Application of Biosolids
SOURCES/TRANSPORT • Wastewater treatment facilities not currently designed to treat pharmaceuticals • Pharmaceuticals not fully removed/transformed in conventional wastewater treatment processes • Studies show some attenuation and degradation within treatment processes including: Sorption Biodegradation Abiotic Oxidation Volatilization Filtration
SOURCES/TRANSPORT Most pharmaceuticals are transported from land to surface water and groundwater by complex processes. Along the way very complex reactions occur some of which are: Phototransformation Physiochemical alteration Sorption Degradation Mineralization Volatilization Plant uptake Uptake by organisms Human consumption
SOURCES/TRANSPORT Very complex processes in the environment • Chemical/water interactions • Chemical/soil interactions • Chemical/sediment interactions • Chemical/plant/organism interactions • Chemical/chemical interactions
SOURCES/TRANSPORT WATER WATER SOIL/SEDIMENTS CHEMICAL PLANTS/ORGANISMS WATER OTHER CHEMICALS
REGULATORY FRAMEWORK CANADA • New Substances Notification Regulations of the Canadian Environmental Protection Act, 1999- environmental assessments • Predict concentration of a proposed pharmaceutical in the wastewater treatment effluent or in the receiving body of surface water • Toxicity testing requirements Limitation: what are the daughter products and their effects and interactions between pharmaceuticals?
CURRENT CANADIAN RESEARCH THE CENTRE FOR CONTROL OF EMERGING CONTAMINANTS Interdisciplinary group of most respected water scientists in Canada • Emerging Contaminants refers to thousands of chemicals including, but not exclusive, to pharmaceuticals released daily to our water systems • Researchers from Civil and Environmental Engineering, Chemical Engineering, Earth Sciences, Biology and Geography • Researchers from University of Waterloo, University of Guelph Wilfrid Laurier, Trent University, and University of Toronto • Fifteen researchers including Dr. Ed McBean- University of Guelph
Some Evolutionary Aspects There are 23,000 drugs registered in Canada’s drug market Synthetic estrogen used in birth control pills Parts per trillion or 0.005 ug/L Males became indistinguishable from females and produced eggs instead of sperm LC-MS-MS
Some Additional Background Where do unused drugs go: 2% to 20% are returned to pharmacy 54% are in solid waste 11% - 35% into toilet Depends on pharmaceutical, but common for 90% excreted
Features that Influence Where the Pharmaceuticals Go Sorption Hydrophilic – remain dissolved Hydrophobic – bind to solids Biodegradation Volatilization
Examples of Fate and Transport Carbemazepine – an anti-depressant E.g. detected at 0.65 ug/L, 400 m from WWTP discharge point Typically, about 10% removal in wastewater treatment Ibuprofen – an anti-inflammatory Typically, about 93-95% removal in wastewater treatment
Carbemazepine Approximately 28% excreted Resistant to biodegradation (1/2 life of 100 days) Low Henry’s law so doesn’t volatilize Not high in sorption Conclusion – ends up in the aqueous phase
Metabolites and their molecular structures, CAS No., formula, and molecular weights
Ibuprofen Biodegrades High sorption Low volatility i.e. Much of it disappears
CURRENT CANADIAN RESEARCH OBJECTIVES OF THE CCEC: • Develop /test new technologies to better control pharmaceuticals • Improve existing technologies for removal of pharmaceuticals • Develop analytical technologies for measuring pharmaceuticals in complex streams • Contribute to the development of scientific-based policy to control pharmaceuticals • Evaluate the impact of pharmaceuticals in surface and groundwater systems
FUTURE RESEARCH AND CHALLENGES • Continue to advance level of knowledge on the fate and transport of pharmaceuticals in the environment • Continue to advance analytical techniques for the detection of pharmaceuticals • Continue work on the toxicology of these chemicals • Continue to develop advanced treatment technologies such as advanced-oxidation processes and reverse osmosis • Examine the economics of advanced treatment technologies
FUTURE RESEARCH AND CHALLENGES • Advanced treatment technologies require a large capital investment and a large amount of electricity to operate • For example a recent study reported that the amount of mass of pharmaceuticals removed, although not destroyed, through advanced treatment systems is on the order of 5 grams per day! • Therefore it is very important to integrate all of the scientific research together to satisfy environmental stewardship, socioeconomic and financial responsibilities.
Conclusions Much still remains to be learned Knowledge of coefficients suggests where the specific pharmaceutical will end up Longevity is very dependent on the pharmaceutical