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Document ID ca-padw-2016-06-30 Title Perfluorooctanoic Acid (PFOA) in Drinking Water URL https://www.canada.ca/en/health-canada/programs/consultation-perfluorooctanoic-acid-pfoa-in-drinking-water/document.html Jurisdiction /ca Subdomain(s) Drinking water, Water quality, Treatment Language en Status completed Analyzed at 2026-03-16 07:44:36.563370+00:00 Relevance Proposed drinking water guideline and technical guidance for PFOA treatment.

Q Qualitative Requirements (32)

Req ID Category Intent Legal Status Name Subdomain(s) Context Conditions Confidence
#Q001administrativeoperationalrecommendedGuidance on Implementationdrinking waterSpecific guidance related to the implementation of drinking water guidelines should be obtained from the appropriate drinking water authority in the affected jurisdiction.When implementing the drinking water guidelines.high
#Q002monitoringoperationalrecommendedSource Water Characterizationdrinking waterUtilities should characterize their source water to assess PFOA concentrations.high
#Q003monitoringhealthrecommendedMonitoring Frequency for Exceedancesdrinking waterIn source waters where PFOA is present at levels exceeding the proposed MAC, quarterly monitoring of surface water and semi-annual monitoring of groundwater should be conducted.Applies where PFOA is present at levels exceeding the proposed MAC.high
#Q004monitoringtreatmentguidanceEnhanced Monitoring for GAC Systemsdrinking waterUtilities that use a GAC system for PFOA removal may want to enhance monitoring of the treated water in order to assess the performance of the GAC system and to determine the timing of the regeneration.Applies to utilities that use a GAC system for PFOA removal.high
#Q005monitoringoperationalguidanceReduced Monitoring Criteriadrinking waterUtilities may consider reduced monitoring when they have data indicating that PFOA does not occur in the source water.When data indicates that PFOA does not occur in the source water.high
#Q006monitoringhealthguidanceMonitoring for Other PFAAs (AFFF Contamination)drinking waterHowever, if the main source of groundwater contamination is suspected to be from the use of AFFF, utilities may want to consider monitoring for other perfluorinated alkyl acids (PFAAs; i.e., shorter chain compounds such as perfluorobutanoic acid and perfluorobutane sulfonate).Applies if the main source of groundwater contamination is suspected to be from the use of AFFF.high
#Q007monitoringoperationalmandatoryIsotope-labelled Internal Standards Usagedrinking waterIn addition, the use of isotope-labelled internal standards is a standard practice and must be used in the analysis of PFAS.During the analytical quantification of PFAS.high
#Q008operationaloperationalrecommendedContamination Avoidance in Clean-updrinking waterCare should be taken to avoid contamination of the extract or losses of PFASs during the clean-up procedures.During sample extraction and clean-up procedures prior to instrumental determination.high
#Q009operationaloperationalrecommendedAvoidance of Fluoropolymer Materialsdrinking waterContacts with such laboratory materials and products during analysis of PFOA should be avoidedPertains to fluoropolymers (e.g., PTFE) during laboratory analysis.high
#Q010operationaloperationalrecommendedAvoidance of Glassware for Samplingdrinking waterISO method 25101 and EPA Method 537 recommended against the use of glassware for sampling due to the potential adsorption of PFOA on the wallsDuring collection and storage of water samples intended for PFOA analysis.high
#Q011operationaloperationalrecommendedSample Storage and Preservation Constraintsdrinking waterThe storage and sample preservation steps prior to the instrumental analysis should prevent changes in composition of the sample matrix and the concentration of the analytePrior to instrumental analysis.high
#Q012monitoringtreatmentmandatoryGAC Breakthrough Monitoringdrinking waterClose monitoring of PFOA breakthrough (treatment objective) is necessary for efficient operation of GAC unit.When utilizing a Granular Activated Carbon (GAC) unit for treatment.high
#Q013treatmenttreatmentrecommendedResidential Device Usage Suggestiondrinking waterGenerally, it is not recommended that drinking water treatment devices be used to provide additional treatment to municipally treated water.Applies to municipal water connections (residential level).high
#Q014treatmenttreatmentrecommendedCertified Treatment Devices Usagedrinking waterHealth Canada does not recommend specific brands of drinking water treatment devices, but it strongly recommends that consumers use devices that have been certified by an accredited certification body as meeting the appropriate NSF International (NSF)/American National Standards Institute (ANSI) drinking water treatment unit standards.When consumers select a residential drinking water treatment device.high
#Q015treatmenttreatmentrecommendedPoint-Of-Use Limitation for RO Systemsdrinking waterRO systems should only be installed at POU as the water they have treated may be corrosive to internal plumbing components.Applies to Reverse Osmosis (RO) residential systems.high
#Q016treatmenthealthrecommendedNSF/ANSI Standard 61 Certification Requirementdrinking waterHealth Canada strongly recommends that homeowners ensure that these systems are constructed using materials certified to NSF/ANSI Standard 61 (NSF/ANSI, 2014).For ion exchange or residential treatment systems.high
#Q017monitoringoperationalrecommendedResidential Pre-installation Water Testingdrinking waterBefore a treatment device is installed, the water should be tested to determine general water chemistry and verify the presence and concentration of PFOA.Prior to installation of a residential treatment device.high
#Q018monitoringtreatmentrecommendedResidential Device Effectiveness Verificationdrinking waterPeriodic testing by an accredited laboratory should be conducted on both the water entering the treatment device and the finished water to verify that the treatment device is effective.For residential treatment devices in use.high
#Q019monitoringoperationalmandatoryPFAS Analysis Quality Control Proceduresdrinking waterIn order to generate accurate data, quality control (QC) procedures (matrix spikes, duplicates, spike-recovery experiments, surrogate recovery checks) are critical.During the trace quantitation of PFASs in environmental water samples.high
#Q020operationaloperationalrecommendedSPE Device Contamination Testingdrinking waterThe U.S. EPA (2009a) recommends that SPE devices be tested prior to using them for analysis to ensure that there is no contamination of the sample.Prior to using Solid Phase Extraction (SPE) devices for analysis.high
#Q021designtreatmentmandatoryGAC System Design and Operationdrinking waterIn order to achieve a PFOA concentration below 0.2 µg/L, the GAC system must be specifically designed and appropriately operated for PFOA removal in drinking water.When utilizing Granular Activated Carbon (GAC) for PFOA removal to levels below 0.2 µg/L.high
#Q022operationaloperationalmandatoryRO Concentrate DisposalotherRO rejects a significant portion of the influent water as contaminant-rich brine, and the concentrate discharge must be disposed of appropriately.When utilizing Reverse Osmosis (RO) treatment systems.high
#Q023operationaloperationalmandatoryRO Post-Treatment Corrosion Controldrinking waterThe removal of contaminants can cause mineral imbalances that could increase the corrosive nature of the treated water. In most cases, post-treatment corrosion control measures need to be taken.Post-treatment following Reverse Osmosis (RO) to mitigate potential corrosivity.high
#Q024treatmenttreatmentguidanceIon Exchange Pre-treatment Requirementdrinking waterIf an ion exchange system is used, the water may need to be filtered through a GAC filter to remove any chlorine or chloramine (if connected to a treated water supply) from the water before it reaches the resin.When using an ion exchange system connected to a treated water supply containing chlorine or chloramine.high
#Q025operationaloperationalguidanceAnalytical Sample Pre-treatment Filtrationdrinking waterPrior to a SPE, a sample pre-treatment (filtration) may be required to facilitate extraction or to remove matrix constituent that will interfere with analyses.Prior to a Solid Phase Extraction (SPE).high
#Q026treatmenttreatmentguidanceResidential RO Influent Pre-treatmentdrinking waterA consumer may need to pre-treat the influent water to reduce fouling and extend the service life of the membrane.When using a residential Reverse Osmosis (RO) system.high
#Q027operationaloperationalrecommendedNanofiltration Pilot and Full-Scale Testingdrinking waterTesting of the selected NF membrane for PFOA removal at both pilot- and full-scale is an important step for utilities when considering this treatment process.When a utility is considering the implementation of nanofiltration (NF) treatment.high
#Q028designtreatmentrecommendedNF Membrane Selection Criteriadrinking waterSince the size exclusion is an important mechanism for PFASs rejection by NF membranes, consideration should be taken to select membranes with MWCO smaller than the size of PFOA.During the selection of nanofiltration (NF) membranes for PFAS rejection.high
#Q029treatmenttreatmentguidanceTreatment Selection for Long-Chain PFASdrinking waterIf long-chain PFASs are detected in the drinking water sources, the utility may consider the implementation of treatments such as GAC.When long-chain PFASs are detected in drinking water sources.high
#Q030treatmenttreatmentguidanceTreatment Selection for Short-Chain PFASdrinking waterHowever, utilities that have shorter chain PFASs in their raw water source may choose to implement RO or NF.When shorter chain PFASs are detected in the raw water source.high
#Q031operationaltreatmentmandatoryGAC Media Replacementdrinking waterWhen the adsorption capacity of the GAC is exhausted, it must be removed from the contactor and replaced with fresh or reactivated carbon.When the adsorption capacity of the GAC media is exhausted.high
#Q032operationaltreatmentmandatoryResidential Device Maintenance and Replacementdrinking waterDevices can lose removal capacity through use and time and need to be maintained and/or replaced.Applies to residential treatment devices.high

P Quantitative Requirements (29)

Req ID Category Intent Legal Status Name Subdomain(s) Limit Type Limit Value Context Conditions Confidence
#P001chemicalhealthguidelinePFOAdrinking waterMAC0.0002 mg/LA maximum acceptable concentration (MAC) of 0.0002 mg/L (0.2 µg/L) is proposed for PFOA in drinking water.Applies to the general populationhigh
#P002chemicalhealthguidelinePFOAdrinking waterMAC0.2 µg/LA maximum acceptable concentration (MAC) of 0.0002 mg/L (0.2 µg/L) is proposed for PFOA in drinking water.Applies to the general populationhigh
#P003operationalreportingrecommendedSurface water monitoring frequencydrinking waterrequirement4 per yearQuarterly monitoring of surface water should be conducted.In source waters where PFOA is present at levels exceeding the proposed MAChigh
#P004operationalreportingrecommendedGroundwater monitoring frequencydrinking waterrequirement2 per yearSemi-annual monitoring of groundwater should be conducted.In source waters where PFOA is present at levels exceeding the proposed MAChigh
#P005chemicalhealthguidelinePFOA Health-Based Value (Cancer)drinking waterrequirement0.03 mg/LThe HBV for PFOA in drinking water is 0.03 mg/L (rounded).Based on Leydig cell tumours in male ratshigh
#P006chemicalreportingmandatoryPFOA MRL (UCMR3)drinking waterrequirement20 ng/LUCMR3 stipulates that an MRL of 20 ng/L (0.02 µg/L) for PFOA must be achieved and reported.When using Method 537 ver. 1.1high
#P007chemicalhealthguidelinePFOA Health-Based Value (Non-cancer)drinking waterrequirement0.0002 mg/LUsing this TDI, the HBV for drinking water can be calculated as follows: The HBV for PFOA in drinking water is 0.0002 mg/L.Based on hepatocellular hypertrophy in ratshigh
#P008chemicalhealthguidelineTolerable Daily Intake (TDI) - Cancerdrinking waterrequirement0.003 mg/kg bw per dayUsing the calculated PODHEQ, the cancer TDI was calculated as follows: The TDI for PFOA is 0.003 mg/kg bw per day.Based on PODHEQ associated with the NOAEL for Leydig cell tumours in male ratshigh
#P009chemicalhealthguidelineTolerable Daily Intake (TDI) - Non-cancerdrinking waterrequirement0.000025 mg/kg bw per dayUsing the calculated PODHEQ, the non-cancer TDI was calculated as follows: The non-cancer TDI for PFOA is 0.000025 mg/kg bw per day.Based on PODHEQ calculated for hepatocellular hypertrophy in ratshigh
#P010chemicalreportingguidanceMDL for PFOA (EPA Method 537)drinking waterrequirement1.7 ng/LThe MDL for PFOA is 1.7 ng/L (0.0017 µg/L) using Method 537 ver. 1.1.high
#P011chemicalreportingguidanceLCMRL for PFOA (EPA Method 537)drinking waterrequirement5.1 ng/LThe Lowest Concentration Minimum Reporting Level (LCMRL) is 5.1 ng/L (0.0051 µg/L) using Method 537 ver. 1.1.high
#P012chemicalreportingguidanceLOQ for PFOA (3M Method ETS-8-154.3)drinking waterrequirement25 ng/LThe method (ETS-8-154.3) has a limit of quantitation (LOQ) of 25 ng/L (0.025 µg/L) for PFOA.high
#P013operationaltreatmentrecommendedGAC Replacement Frequencydrinking waterrequirement3 - 6 monthsStudies indicated that PFOA was successfully removed from drinking water when a frequent regeneration or replacement (3 to 6 months) of the GAC was performed.For utilities specifically targeting PFOA removalhigh
#P014chemicalreportingguidanceISO Method 25101 concentration rangedrinking water, otherrequirement10 - 10,000 ng/LISO Method 25101 was found to be appropriate for determination of PFOA levels in unfiltered samples of drinking water, groundwater and surface water with concentrations in the range of 10 - 10,000 ng/L (0.01 - 10 µg/L).Unfiltered samples of drinking water, groundwater and surface waterhigh
#P015chemicalreportingguidancePFOA limit of detection (LOD) - SPE/LC-MS/MSdrinking waterrequirement0.28 ng/LA study reported a limit of detection (LOD) (signal-to-noise [S/N] = 3:1) of 0.28 ng/L... using an SPE followed by LC-MS/MS for analyzing PFOA in surface water.Signal-to-noise (S/N) = 3:1high
#P016chemicalreportingguidancePFOA limit of quantitation (LOQ) - SPE/LC-MS/MSdrinking waterrequirement0.94 ng/LA study reported... an LOQ (S/N= 10:1) of 0.94 ng/L using an SPE followed by LC-MS/MS for analyzing PFOA in surface water.Signal-to-noise (S/N) = 10:1high
#P017chemicalreportingguidancePFOA limit of detection (LOD) - SPE/LC-MS/MS (Villaverde-de-Saa)drinking waterrequirement0.03 ng/LReported by Villaverde-de-Saa et al. (2015) using SPE followed by LC-MS/MS.Calculated as 3 times the standard deviationhigh
#P018chemicalreportingguidancePFOA limit of quantitation (LOQ) - SPE/LC-MS/MS (Villaverde-de-Saa)drinking waterrequirement0.11 ng/LReported by Villaverde-de-Saa et al. (2015) using SPE followed by LC-MS/MS.Calculated as 10 times the standard deviationhigh
#P019chemicalreportingguidancePFOA limit of quantitation (LOQ) - Direct Injection (Furdui et al.)drinking waterrequirement0.5 ng/LReported by Furdui et al. (2008) for samples from the Great Lakes.Signal-to-noise [S/N] = 10:1high
#P020chemicalreportingguidancePFOA detection limit (DL) - Finished Water (Quebec)drinking waterrequirement0.3 - 0.6 ng/LReported detection limits for finished water in Quebec province monitoring.500 mL sample analyzedhigh
#P021chemicalreportingguidancePFOA detection limit (DL) - Untreated Water (Quebec)drinking waterrequirement0.5 - 1.0 ng/LReported detection limits for untreated water in Quebec province monitoring.250 mL analyzed samplehigh
#P022chemicalhealthguidelinePFOA Provisional Health Advisory (US EPA)drinking waterrequirement0.4 µg/LThe U.S. EPA Office of Water indicates a Provisional Health Advisory (PHA) of 0.4 μg/L (0.0004 mg/L) for PFOA.Derived from a BMDL10 of 0.46 mg/kg bw per day for increased maternal liver weight in micehigh
#P023chemicalhealthguidelinePFOA preliminary health-based guidance (New Jersey)drinking waterrequirement0.04 µg/LThe New Jersey Department of Environmental Protection derived a preliminary health-based guidance of 0.04 μg/L.Derived from NOAEL of 1.6 mg/kg bw per day in ratshigh
#P024chemicalhealthguidelinePFOA health risk limit (HRL) (Minnesota)drinking waterrequirement0.3 µg/LThe Minnesota Department of Health derived a health risk limit (HRL) of 0.3 μg/L (0.0003 mg/L).Based on increased liver weight in monkeyshigh
#P025chemicalhealthguidelinePFOA drinking water guideline (UK HPA)drinking waterrequirement10 µg/LA drinking water guideline of 10 μg/L (0.01 mg/L) was derived by the UK Health Protection Agency.Based on a TDI of 3,000 ng/kg bw per dayhigh
#P026chemicalhealthguidelinePFOA Tolerable Daily Intake (TDI) (EFSA)drinking waterrequirement1500 ng/kg bw per dayThe CONTAM panel under EFSA derived a TDI of 1,500 ng/kg bw per day (1.5 μg/kg bw per day).Based on a BMDL10 of 0.3 mg/kg bw per day in rats for liver effectshigh
#P027chemicalhealthguidelinePFOA Tolerable Daily Intake (TDI) - UK HPAdrinking waterrequirement3000 ng/kg bw per dayA drinking water guideline of 10 μg/L was derived by the UK Health Protection Agency based on a TDI of 3,000 ng/kg bw per day.As established by the UK Committee on Toxicityhigh
#P028chemicalhealthguidelinePFOA Drinking Water Allocation Factordrinking waterrequirement20 %The default allocation factor for drinking water of 20% is used for PFOA as a floor value when water is a minor contributor to exposure.Applicable for the general populationhigh
#P029designtreatmentguidancePFOA Treatment Goal - Residential Reverse Osmosisdrinking watertreatment_goal< 0.05 µg/LAvailable data suggests that residential reverse osmosis can achieve treated PFOA concentrations below 0.05 µg/L.For residential scale applicationshigh

D Definitions (124)

Req ID Category Name Context Confidence
#D001PFOAThe term "PFOA" may refer to the free acid (C8HF15O2; CAS number 335-67-1; 414.07 g/mol) or its conjugate base (C8F15O2-; CAS number 45285-51-6).high
#D002APFOThe term APFO (ammonium perfluorooctanoate) refers to the ammonium salt (C8F15O2- NH4+; CAS number 3825-26-1), its principal salthigh
#D003K+PFOAK+PFOA refers to the potassium salt (CAS number 2395-00-8).high
#D004probable linkThe "probable link" defined by the Science Panel means that "given the available scientific evidence, it is more likely than not that among class members a connection exists between PFOA exposure and a particular human disease."high
#D005suitable BMDLA suitable BMDL is defined as a lower 95% confidence limit estimate of dose corresponding to a 1-10% level of risk over background levels.high
#D006AFFFaqueous film-forming foamhigh
#D007ALTalanine transaminasehigh
#D008APFOammonium perfluorooctanoatehigh
#D009BMDbenchmark dosehigh
#D010BMDLlower confidence limit on the benchmark dosehigh
#D011BMDL 10lower 95% confidence limit on the benchmark dose for a 10% responsehigh
#D012BVbed volumehigh
#D013CASChemical Abstracts Servicehigh
#D014CIconfidence intervalhigh
#D015CSAFchemical specific adjustment factorhigh
#D016DIdirect injectionhigh
#D017DLdetection limithigh
#D018EBCTempty bed contact timehigh
#D019EPAEnvironmental Protection Agency (U.S.)high
#D020ESIelectrospray ionizationhigh
#D021GACgranular activated carbonhigh
#D022GDgestational dayhigh
#D023GMgeometric meanhigh
#D024HBVhealth-based valuehigh
#D025HPLChigh performance liquid chromatographyhigh
#D026ISOInternational Standard Associationhigh
#D027ITion-traphigh
#D028LCliquid chromatographhigh
#D029LOAELlowest-observed-adverse-effect levelhigh
#D030LODlimit of detectionhigh
#D031LOQlimit of quantitationhigh
#D032LLEliquid-liquid extractionhigh
#D033MACmaximum acceptable concentrationhigh
#D034MDLmethod detection limithigh
#D035MGDmammary gland developmenthigh
#D036MG/Dmillion gallons per dayhigh
#D037MOAmode of actionhigh
#D038MRLminimum reporting levelhigh
#D039MS/MStandem mass spectrometryhigh
#D040NFnanofiltrationhigh
#D041NOAELno-observed-adverse-effect levelhigh
#D042NOMnatural organic matterhigh
#D043PACpowdered activated carbonhigh
#D044PBPKPhysiologically-based pharmacokinetichigh
#D045PEFTpolytetrafluoroethylenehigh
#D046PFAperfluoroalkylhigh
#D047PFAAperfluorinated alkyl acidhigh
#D048PFASperfluoroalkyl substancehigh
#D049PFCAlong-chain perfluorocarboxylic acidshigh
#D050PFOAperfluorooctanoic acidhigh
#D051PFOSperfluorooctane sulfonatehigh
#D052PNDpostnatal dayhigh
#D053PODpoint of departurehigh
#D054POD HEQhuman-equivalent points-of-departurehigh
#D055PTFEpolytetrafluoroethylenehigh
#D056RBFriver bank filtrationhigh
#D057ROreverse osmosishigh
#D058SPEsolid phase extractionhigh
#D059TDItolerable daily intakehigh
#D060TDStotal diet studyhigh
#D061UCMR3third Unregulated Contaminant Monitoring Rule (U.S.)high
#D062WAXweak anion exchangehigh
#D063LCMRLLowest Concentration Minimum Reporting Levelhigh
#D064alumaluminum sulfatehigh
#D065MWCOmembrane molecular weight cut-offhigh
#D066CNTsCNTs are carbon molecules composed of carbon lattices that can take the form of tubes.high
#D067ChitosanChitosan is a natural polysaccharide based on the shells of crustaceans.high
#D068Molecular imprintingMolecular imprinting is a technique where specific sites for target compounds are constructed on a polymer so that specific adsorbates are recognized in the sorption process.high
#D069ENFMsENFMs are prepared by electrospinning nanofibers of polymer or polymer composite materials to create membranes of non-woven fibers with diameters ranging from several hundreds to tens of nanometershigh
#D070AKUFtoxicokinetic portion of the interspecies uncertainty factorhigh
#D071ADUFtoxicodynamic componenthigh
#D072Vdvolume of distribution, which is the theoretical volume of blood in which the amount of a chemical would need to be uniformly distributed to produce the observed blood concentrationhigh
#D073MGD scoreMGD is scored on a 1-4 subjective, age-appropriate developmental scale based on the number of primary ducts and large secondary ducts, lateral side branching, appearance of budding from the ductal tree, and longitudinal outgrowth of the epithelia.high
#D074pKaacid dissociation constanthigh
#D075Kowoctanol:water partition coefficienthigh
#D076PFCAsperfluorocarboxylic acidshigh
#D077PFAsperfluoroalkylshigh
#D078PAPspolyfluoroalkyl phosphate surfactanthigh
#D079PAAdi-perfluoro-alkyloxy-amino-acidhigh
#D080S-PACssuperfine PACshigh
#D081AOPsAdvanced oxidation processes (AOPs) have been developed for removal of contaminants that are resistant to more typical chemical oxidation treatment processes. They include the use of appropriate combinations of ultraviolet (UV) light, chemical oxidants and catalysts (e.g., ozone, hydrogen peroxide, titanium dioxide) to generate highly reactive radicals, such as hydroxyl radicals, which are strong oxidants and react rapidly and non-selectively with organic contaminants.high
#D082MIPschitosan-based molecularly imprinted polymershigh
#D083L-FABPrat liver fatty acid binding proteinhigh
#D084PHAProvisional Health Advisoryhigh
#D085HRLhealth risk limithigh
#D086HEDhuman equivalent dosehigh
#D087RfDreference dosehigh
#D088C8 Health ProjectThe C8 Health Project is the largest study of a population exposed to PFAAs in drinking water, containing residents of Ohio and West Virginia communities surrounding the DuPont Washington Works plant.high
#D089C8 Science PanelThe C8 Science Panel was convened as a result of a class action settlement against DuPont, and is composed of independent epidemiologists jointly selected by lawyers for the community and DuPont.high
#D090PFASsParticle-bounded volatile perfluoroalkyl substanceshigh
#D091PFAAsperfluorinated alkyl acidshigh
#D092PAClpolyaluminium chloridehigh
#D093RSSCTsRapid small-scale column testshigh
#D094DOCdissolved organic carbonhigh
#D095MFmicrofiltrationhigh
#D096UFultrafiltrationhigh
#D097gfdgallons per square foot per dayhigh
#D098PEEKpolyetheretherketonehigh
#D099NMRnuclear magnetic resonancehigh
#D100TOFtime-of-flighthigh
#D101OATsorganic ion transportershigh
#D102BAFsbioaccumulation factorshigh
#D103BCFsbioconcentration factorshigh
#D104S/Nsignal-to-noisehigh
#D105RBFRiver bank filtration (RBF) is a drinking water treatment method where surface water flows through the subsurface sand and gravel layers of the bank or bed of a river to extraction wells and contaminants are removed through the processes of filtration, sorption, dilution and biodegradation.high
#D106ln 2natural log of 2high
#D107T1/2half-life of a compoundhigh
#D108TEBsterminal end budshigh
#D109TDsterminal ductshigh
#D110WYWyeth-14,643high
#D111CLCL is clearance in animals and humans (e.g., mL/kg bw per day).high
#D112POUpoint-of-use (POU)high
#D113POEpoint-of-entry (POE)high
#D114ASTaspartate transaminase (AST)high
#D115GGTgamma glutamyl transpeptidase (GGT)high
#D116ADHDattention deficit/hyperactivity disorder (ADHD)high
#D117AICAkaike information criterion [AIC]high
#D118CDWFederal-Provincial-Territorial Committee on Drinking Waterhigh
#D119IARCInternational Agency for Research on Cancerhigh
#D120PFBAperfluorobutanoic acidhigh
#D121PFBSperfluorobutane sulfonatehigh
#D122PFHpAperfluoroheptanoic acidhigh
#D123PFHxSperfluorohexanesulfonatehigh
#D124PFHxAperfluorohexanoic acidhigh