Urban Water Security Research Alliance

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1 Urban Water Security Research Alliance Reduction of Pharmaceutical Loads in Municipal Wastewater: Would Onsite Treatment of Hospital Wastewater be Effective? Kristell Le Corre Hospital Wastewater Science Forum, June 2012

2 FROM SEWERS TO TREATMENT PLANTS Wastewater as a resource Energy (sewage/sludge) Domestic wastewater SEWER WWTP Recycling Water (AWTP) Stormwater Nutrients (P, N) Discharge to the environment Industrial effluents SUBJECT TO TRADE Hospital effluents WASTE APROVALS???

3 TRADE WASTE What about hospitals? CURRENT LEGISLATION Wastewater including toilets, showers and hand basins is considered as domestic wastewater. All other waste discharged (labs etc.) from hospitals to the sewer is considered as trade waste. BUT Parameters (mg/l) Unit Domestic wastewater Hospital wastewater ph BOD (average) COD 250-1, (average) mg/l SS (average) TN TP Total coliforms unit/100ml Analgesics Antibiotics Cytostatics ß-Blockers µg/l ICM ,008 Gadolimum Platinum AOX Verlicchi et al., (2010) Journal of Hydrology, 389,

4 ARE HOSPITALS A MAJOR POINT SOURCE? Hospitals are seen as significant contributors of toxic or hazardous compounds such as heavy metals, cleaning chemicals, pharmaceuticals, pathogenic organisms. Should additional source control through onsite treatment be applied? Would onsite treatment of hospital wastewater be an effective way to reduce pharmaceutical loads in municipal wastewater, hence in the feed of AWTP?

5 ARE HOSPITALS A MAJOR POINT SOURCE? Contradictory results to date Human medicine If, for whatever motivation, hospital wastewater shall be treated separately onsite, it must be noted, that for many substances no major overall reduction can be achieved since many pharmaceuticals are taken on a regular basis at home.. Ort et al., Water Res. Excretion Wastewater Municipal Wastewater + Hospital Wastewater WWTP Surface Water Drinking water Informed scientists agree that urgent measures must be taken in order to set guidelines for the treatment of HWWs. Experimental studies are also necessary because there is still a remarkable paucity of data concerning the possible impacts of HWW on the environment. Verlicchi et al, Wat. Sci. Tech.

6 THE HOSPITAL WASTEWATER PROJECT Experimental approach vs. Predictive approach

7 EXPERIMENTAL APPROACH

8 CASE STUDY: CABOOLTURE HOSPITAL Caboolture Hospital flow contribution to STP is 1%

9 CABOOLTURE HOSPITAL Summary of results 59 substances n=17 max <5% n=11 5%< max <15% n=2 max >15% n=5 Only detected at hospital n=24 Not detected above LOQ at both sites

10 LIMITATIONS OF THE EXPERIMENTAL APPROACH Analytical methods Access to sewers Diversity and number of active ingredients High flow and concentration variations 4900 Active Ingredients (TGA, 2011) 150 detected Active Ingredients worldwide (Runnalls et al., 2010) Site specificity (hospital - catchment)

11 PREDICTIVE APPROACH

12 A novel approach using pharmaceutical consumption audit data in hospitals and by the general population Evaluation of the contribution (%) of a hospital to the loads of pharmaceuticals in municipal wastewater METHODOLOGY Contribution Mass (%) Consumption Hospital X = Mass Mass Excretion Consumption Consumption X ratio Hospital Hospital Mass Mass Mass Excretion Consumption + Consumption X ratio + Consumption Hospital Population Population X 100 Excretion ratio

13 AUDIT DATA Mass Consumption Hospital Mass Consumption Population Queensland Public Hospitals Audit Data (Medication Services Queensland) National Consumption (Medicare Australia Pharmaceutical benefit scheme - PBS) Medicines dispensed annually to in-patients in public hospitals by strength, brand, form and quantity Annual amount of medicines subsidised by the general population in Australia > 2000 Hospitals Entries Distinct generics 923 >733 Entries Distinct generics

14 HOSPITALS AND COMPOUNDS INVESTIGATED Identification Determination and of the quantification contribution of of compounds the 6 hospitals exclusively investigated used in to hospitals the load (97-100% of 589 screened contribution) compounds that may in require municipal further wastewater. attention.

15 RESULTS Overall pharmaceutical consumption Hospital QEII CAB IPS PC PA RBWH Catchment Oxley CAB IPS Luggage Point Total mass used in hospitals (g/day) Total mass consumed by the general population (g/day) Total mass in the corresponding STP influent (g/day) ,640 1,948 2,324 35,624 5,725 9,542 72,775 72,775 72,775 36,105 6,065 10,098 79,688 Overall contribution 1% 6% 6% 9%

16 RESULTS Contributions of the 6 hospitals investigated Contribution <15% 15 % < Contribution <50% Y axis = Percentage of compounds per contribution classes 50 < Contribution <97% Contribution >97% % For The 63 percentage to 84 % of of the compounds compounds, exclusively the used at hospitals contribution ranges of from an 10% individual at QEII to hospital 20% at RBWH is likely to be less than 15%

17 RESULTS Hospital specific pharmaceuticals Percentage of compounds returning a hospital contribution between 97 and 100% 153 Hospital-specific compounds A high contribution may not be synonymous of a high consumption / or level in wastewater and excretion in hospitals ABACAVIR - ANTIVIRAL (HIV treatment) Contribution 100% Consumption 0.06 g y -1 bed -1 to 0.3 g y -1 bed -1 Predicted Concentration Heff 0.3 µg L -1 to 1.0 µg L -1 Predicted Concentration STPinf µg L -1 to µg L -1 Prescription mode Comment Qualified medical practitioners through hospital-based pharmacies (HSDP, 2011) Most likely excreted at home Overestimated contribution

18 EFFECT EVALUATION Percentage of compounds returning a hospital contribution between 97 and 100% 153 Hospital-specific compounds Prediction of concentrations (µg L -1 ) in hospital effluents and influents of the corresponding STPs Determination of an effect threshold (µg L -1 ) for each of the hospital-specific compounds Comparison of predicted concentrations with effect thresholds as margin of exposure (MOE) Effect threshold MOE >100 = Unlikely to Predicted cause concern concentration for human (H eff health or STP inf ) Method derived from the Australian guidelines for water recycling: augmentation of water supply (NRMC2008)

19 RESULTS List of hospital-specific compounds with an MOE <100 in influent of STPs Hospitals QEII CAB IPS PC PA RBWH Number of hospital-specific compounds Number of compounds with a MOE in Hospital Effluent Number of compounds with a MOE in STP influent Generic name Therapeutic class MOE Bupivacaine Anaesthetic Piperacillin Antibiotic Tazobactam Antibiotic Oxybuprocaine Anaesthetic Pancuronium Neuromusc. Blocking agent 1122 NU Ropivacaine Anaesthetic Tropicamide Mydriatic Cefazolin Antibiotic NC NC NC 32 NC NC Infliximab Immunosuppressant NU NU NU NU Vincristine Sulphate Antineoplastic NU NU NU NU Levobupivacaine Anaesthetic NU NU 2978 Suxamethonium Anaesthetic Results available Le Corre et al., (2012), Environment International 45,

20 PREDICTIVE VS. EXPERIMENTAL APPROACH Caboolture hospital Compounds investigated Case Study Predictions 59 over 4 days 589 Selection of compounds Overall results Specific results Analytically measurable For 47% of the compounds CAB Hospital contributed less than 15% 5 compounds exclusively detected at the hospital site 2 compounds, roxithromycin and trimethoprim, with a contribution > 15% Consumed at the hospital For 78% of the compounds CAB Hospital contributes less than 15% 56 hospital specificcompounds 3 compounds (bupivacaine / piperacillin / tazobactam) with MOE<100. Comparison of contribution results Contributions for 75% of the compounds investigated experimentally in good agreement with predictions Roxithromycin Trimethoprim Mean 26% - Max 56 % Mean 10% - Max 18 % 19% 13% Main conclusion Caboolture Hospital is not a major point source

21 EXPERIMENTAL APPROACH PART 2

22 Ipswich Hospital flow contribution to STP is 1.2 % CASE STUDY 2 Ipswich Hospital Population in sewer catchment area approx. 75,000 STP ~ 12 km 3.9 beds / 1000 inhabitants

23 IPSWICH HOSPITAL Sampling location Manhole Control box Data logger Flow measurement Inside view of the system Outside view of the system

24 PRELIMINARY RESULTS Example of a daily flow pattern in the sewer 5:10 pm to 10:00 pm 10:00 pm to 5:30 am 5:30 am to 5:10 pm Flow [L/s] Start of wastewater collection Time [h-min-s] (1 record every 10 second) Collection of 8L bottle

25 Acetaminophen Atenolol Caffeine Carbamazepine Cephalexin Ciprofloxacin Citalopram Dapson DEET Diatrizoate Diclofenac Doxylamine Enrofloxacin Erythromycin Fluoxetine Furosemide Gabapentin Gemfibrozil Hydrochlorothiazide Ibuprofen Indomethacin Iopromide Ketoprofen Lincomycin Metoprolol Naproxen Norfloxacin Perindopril Phenytoin Praziquantel Propanolol Ranitidine Roxithromycin Sertraline Sulfadiazine Sulfamethoxazole Sulfasalazine Tramadol Trimethoprim Venlafaxine Warfarin PRELIMINARY RESULTS Contribution of Ipswich Hospital 41 compounds currently being analysed in both types of wastewater (HWW /STP influent) collected over 3 days. Further analyses planned for compounds exclusively used in hospitals and prioritised using the predictive approach This requires the development of a new analytical method.

26 PRELIMINARY RESULTS Contribution of Ipswich Hospital Measured contribution Predicted contribution (2008) Predicted contribution (2009) Hospital contribution (%)

27 Experimental approach OVERALL CONCLUSIONS Caboolture : > 80% of pharmaceutical loads do not originate from hospital. Ipswich: - preliminary results suggest low contributions of this hospital. - corresponding predicted contributions in good agreement or overestimated. Sampling pharmaceuticals in hospital wastewater is time consuming and requires thorough planning to minimise uncertainties. Limited to a certain number of compounds that are analysable. Predictive approach Allows screening silmutaneously numerous pharmaceuticals used in hospitals and identifying potential compounds of concern (specificially used in hospitals) that may require monitoring. Results compare well with experimental results obtained to date. Would onsite treatment of hospital wastewater be an effective way to reduce pharmaceutical loads in municipal wastewater, hence in the feed of AWTP? According to the previous results, no. Additional aspects (propogation of antibiotic-resistant bacteria) to consider.

28 Urban Water Security Research Alliance Urban Water Security Research Alliance Queensland Health Medication Services Queensland Drug Utilisation Sub Committee (DUSC) of the Pharmaceutical Benefits advisory committee (PNAC), Department of Health and Ageing Queensland Urban Utilities Lend Lease / Conneq Advanced Water Management Centre

29 Urban Water Security Research Alliance THANK YOU