Development of Environmental Quality Guidelines for Perfluorooctanoic Acid (PFOA)
Environment Canada | Published July 14, 2014
Perfluorooctanoic acid (PFOA) is an anthropogenic substance belonging to a class of chemicals known as perfluorocarboxylic acids (PFCAs) which belong to the broader class of chemicals known as perfluoroalkyls (PFAs). Historical uses of PFOA include applications in industrial processes and in commercial and consumer products. PFOA and its salts are used as polymerization aids in the production of fluoropolymers and fluoroelastomers. Under the Canadian Environmental Protection Act, 1999 (CEPA 1999) the Government of Canada (2012) determined that PFOA (CAS 335-67-1), its salts and its precursors are entering or may be entering the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity. In addition, it is concluded that PFOA and its salts meet the criteria for persistence as set out in the Persistence and Bioaccumulation Regulations, but do not meet the criteria for bioaccumulation.
The scope of this contract is to search, evaluate and summarize the ecotoxicity of PFOA to aquatic and terrestrial organisms and to develop environmental quality guidelines to protect soil, sediment, water, groundwater and wildlife that consumer aquatic life for PFOA covering relevant exposure pathways. The following protocols of the Canadian Council of Ministers of the Environment (CCME) will be followed to the extent possible to develop the environmental quality guidelines:
• “Protocol for the Derivation of Environmental Quality and Human Health Soil Quality Guidelines (CCME 2006) ,
• Protocol for the Derivation of Canadian Sediment Quality Guidelines for the Protection of Aquatic Life (CCME 1999)3,
• A Protocol for the Derivation of Water Quality Guidelines for the Protection of Aquatic Life (CCME 2007)4 and
• the “Protocol for Derivation of Canadian Tissue Residue Guidelines for the Protection of Wildlife that Consume Aquatic Biota” (CCME 1997)5
Existing soil, sediment, water, groundwater, and wildlife environmental quality guidelines for PFOA from other jurisdictions will also be critically evaluated, presented and their potential application to the Canadian guidelines evaluated. This work requires knowledge and expertise in terrestrial and aquatic toxicology, chemistry, statistics, and the development of environmental quality guidelines to protect soil, water, sediment and wildlife that consume aquatic life.
Objectives: The objective is to conduct an extensive literature search and critically evaluate the terrestrial and aquatic toxicity data for PFOA and develop soil, sediment, water, groundwater and wildlife quality guidelines for all relevant land uses and/or pathways. The project will involve researching the scientific literature; critically evaluating toxicological studies for acceptability in guideline development and related bioaccumulation, bioconcentration, and biomagnification data, levels in the environment and synthesizing all collected information in a format that is pre-approved by the Departmental Representative (see Annexes 1 and 2). The Contractor will use the acceptable relevant information in developing guidelines following the procedures provided in CCME (1997, 1999, 2006, 2007) protocols. A technical document summarizing the critical evaluation of toxicity data (identifying acceptable and unacceptable toxicity data), critical data gaps, guideline calculations, assumptions, rationale for exclusion of any data on PFOA toxicity and resulting guidelines will be prepared. All references will be compiled in a format identified by the Departmental Representative. A review and comparison of environmental quality guidelines for PFOA in soil, sediment, water, groundwater and wildlife from other jurisdictions together with their scientific basis and level of protection for the guidelines will be prepared.
The following background reports must also be consulted:
1. Screening Assessment Report for Perfluorooctanoic Acid, its Salts, and its Precursors. Environment Canada and Health Canada, August 2012.
2. Ecological Toxicity Criteria Derivation for Perfluorinated Compounds. Reference: 12-318. Prepared for Transport Canada under Contract with Public Works and Government Services Canada, December 2012. (Available in the original language of publication).
3. Gewurtz 2013. Perfluoroalkyl Acids in the Canadian Environment: Multi-media
assessment of current status and trends. Environment International 59 (2013) 183–200.
It is expected that the Contractor will be in regular contact with the Departmental Representative throughout the duration of the contract.
Statement of Work:
The Contractor must search, critically evaluate and summarize the scientific literature for all relevant ecotoxicology, bioaccumulation, bioconcentration, biomagnification, fate, behaviour and levels of PFOA in Canadian soil, sediment, tissue, water and groundwater pertaining to PFOA in the terrestrial and aquatic environments and develop environmental quality guidelines for soil, sediment, water, groundwater and tissue residue to protect environmental receptors. The Contractor must evaluate existing soil, sediment, water, groundwater, and tissue residue environmental quality guidelines for PFOA from other jurisdictions. A scientific supporting document must be prepared by the Contractor.
Project Description and Tasks:
The Contractor must complete the following tasks:
Task 1. Start-up Meeting/teleconference Call
An initial meeting or telephone conference call with the Departmental Representative and the Project Team will be held to review and finalize the work schedule. At that time, the Contractor will be provided with any relevant materials related to the project.
Task 2: Literature Search and Cataloguing of References
The Contractor shall obtain all relevant ecotoxicology, bioaccumulation/ bioconcentration/ biomagnification and levels in Canadian soil, sediment, water, tissue and groundwater data on PFOA and catalogue all references in a format identified by the Departmental Representative. The Contractor must also search and present all environmental quality guidelines for PFOA from other jurisdictions and sources.
Task 3: Search Fate, Behavior, Use, and Occurrence of PFOA in Canadian Environment
Perform the necessary searches and summarize the details on fate, behavior, use, and occurrence of PFOA in Canadian environment. The recent Government of Canada (2012) publication can provide the basic information from data surveys conducted in 2000 and 2004. The Contractor’s efforts must also include more recent data. The information on fate and behaviour of PFOA will inform the selection of the environmentally relevant pathways to consider in the development of the environmental quality guidelines.
Task 4: Search and Evaluate Toxicity Data
Compile, evaluate and summarize toxicology, bioaccumulation/bioconcentration/ biomagnification, fate, behaviour and levels in Canadian soil, sediment, water, groundwater and wildlife tissue for PFOA. This must include data for direct contact to plants and algae, invertebrates, fish, birds, mammals and other wildlife, and effects on the food chain. Present all relevant data in spreadsheets, including all available information on exposure and test conditions and evaluate the acceptability of each study using the Robust Study Summary (RSS) forms. See Annex 1 for list of fields for soil toxicity studies and Annex 2- RSS for soil toxicity tests. See Annex 3 list of fields for aquatic toxicity tests and Annex 4 Robust Study Summary form for aquatic toxicity tests. Data tables must clearly identify all toxicity test parameters as well as whether toxicity tests were ranked “Acceptable” (termed “Selected” in the soil protocol) or “Unacceptable” (termed “Consulted” in the soil protocol). The Contractor must provide the rationale for why a study was deemed “Unacceptable” for use in guideline development.
The following sources of variability must be compiled to evaluate the appropriateness of the toxicity data:
- test conditions/design (e.g., single species study, community study, mesocosm, etc.)
- test duration
- test concentrations (measured, nominal, appropriate series)
- test containers
- measurements of abiotic variables such as pH, soil organic matter content, soil texture
- form of PFOA tested (e.g. salt, etc.)
- solubility limit of substance tested
- experimental design (i.e., analytical methodology, QA/QC, controls, and number of replicates)
- species name of organisms tested
- description and appropriateness of statistics used in evaluating the data, and
- other factors deemed appropriate in consultation with Departmental Representative.
Task 5: Derive Soil, Sediment, Water, Groundwater and Tissue Residue Quality Guidelines
Develop soil quality guidelines following the CCME protocol (2006) for all land uses for all relevant pathways, including groundwater. This must include a clear rationale for which environmental pathways must be considered based on the physical and chemical properties of PFOA.
Develop guidelines for the protection of aquatic life following the CCME protocol (2007).
Develop guidelines for the protection of sediment biota following CCME protocol (1999).
Develop tissue residue guidelines for the protection of wildlife that consume aquatic life following the CCME protocol (1997).
For all guideline derivation, all calculations must be clearly shown and all assumptions regarding input parameters (e.g., daily threshold effect dose, body weight, soil intake rate, water intake rate, food intake rate, etc.) must be clearly presented and justified.
In the event that there are insufficient acceptable data to derive a full CCME environmental quality guideline for a particular medium, the Contractor must attempt to derive an interim guideline to the degree possible. The derivation procedure, data gaps or other limitations of the interim guideline must be clearly identified.
Task 6: Review of Soil, Water and Groundwater and Tissue Residue Guidelines in Other Jurisdictions and Publications
Other governmental agencies and researchers may have developed soil, sediment, water, groundwater or tissue residue quality guidelines for PFOA. The Contractor must collate these values, conduct a critical review of the scientific basis and data used in generating these guidelines and describe their similarities and differences from the CCME protocol.
Task 7: Prepare Draft Report
Prepare a draft scientific supporting document summarizing the literature search strategy, fate, behavior, use and occurrence in the environment, the acceptable and unacceptable toxicity data, description of details on steps taken in developing the soil, sediment, water, groundwater and tissue residue quality guidelines prepared under Tasks 4 and 5. The draft report must also include an analysis of the basis for soil, sediment, water, groundwater and wildlife quality guidelines for PFOA from other jurisdictions/publications (from Task 6). Finally, identify any gaps in the toxicity data set relative to minimum data sets identified in CCME 2006, 2007 and 1997 and 1999.
Task 8: Address Review Comments
The Contractor must make revisions to the datasets and draft report in response to review comments provided by the Departmental Representative. As well, the Contractor must prepare disposition tables indicating how each review comment was addressed, and submit the revised version of the report.
Task 9: Submit Documents, Files, References
The Contractor must submit to the Departmental Representative the following items as per the milestones identified in the Deliverables section below:
• unprotected electronic files (in MS Word) containing draft and final reports, Robust Study summaries of toxicity studies, detailed tables of acceptable and unacceptable toxicity studies, references and other relevant documentation, and disposition tables.
• unprotected electronic spreadsheets (in MS Excel or Access database) detailing all the toxicity data (acceptable and unacceptable) and the calculation of the soil, water, groundwater and wildlife quality guidelines,
• electronic files of all literature cited.
All deliverables are to be provided to the Departmental Representative no later than the dates specified above. All documents, reports, briefing notes and correspondence generated by the Contractor during the course of this project shall be prepared in English using Microsoft Word for word processing, Microsoft Excel or MS Access for data management, and Microsoft Power Point for presentations and other graphics.
The Contractor is to advise the Departmental Representative of any information provided by a third party on a confidential basis (e.g. confidential information related to contaminated sites or confidential chemical-specific data) for the purpose of the study and is to transmit the original documents containing any such information to the Departmental Representative under separate cover.
All discussion papers, reports and correspondence produced by the Contractor are subject to review by the Departmental Representative or his or her designate. All work is to be performed to the satisfaction of the Departmental Representative.
The Contractor is required to demonstrate sufficient flexibility in order to respond to changing schedules and developments.