“Contaminants of emerging concern” in wastewater: Are current policy development and industry guidelines enough to protect human and ecological health?

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About the project

The modernization of wastewater treatment plants (WWTPs) is a 21st century problem that is elucidated by the ecological and human health challenges presented by chemicals of emerging concern (CEC). Today’s WWTP processes are efficient in removing solid debris, oils and grease, and dissolved and suspended organic matter; however, these processes were not designed to eliminate man-made chemical pollutants generated by industries and households. The federal government recognizes that wastewater effluent is “the largest single effluent discharges, by volume, in the country.” Yet there is little research conducted on how to protect freshwater sources—which serve as drinking water sources and provide habitat for fish, wildlife and microbiota—from CEC effluent discharges from WWTPs. This pervasive CEC pollution problem affects all Canadians and watershed ecosystems and is attributed to three key factors: 1) a legislative gap, including the need for an integrated multi-level regulatory framework, 2) a research gap, including the lack of research on the impacts of CECs on human and ecological health, and 3) an innovation gap, including the limited funding opportunities directed at technology innovation in the WWTP sector. This research included a comprehensive literature review to determine the types and amounts of CEC in wastewater, followed by interviews of experts in the fields of wastewater, CEC contamination and water governance. A workshop is planned for the fall of 2021, where knowledge transfer with experts from utilities, municipalities, government ministries and researchers will occur, leading to a white paper on the issue of CEC regulation in Canadian waters.

Key findings

  • Sparse data exists on the type, number and quantity of each CEC entering and discharged into freshwater sources from wastewater streams, which complicates the assessment of harm(s) and the magnitude of the CEC problem to humans and ecosystems.
  • No standardized analytical methodology guidelines exist to detect the type and quantity of CECs in wastewater effluent.
  • WWTP compliance does not include detection or monitoring procedures to assess the levels of CEC in WWTP processes.
  • Very little research has been conducted on the risks of CEC (i.e., bioaccumulative, mobile, persistent, legacy; and some are known as “forever chemicals”), and this limited research further overlooks the synergistic effects of CEC chemical mixtures.  
  • Little or no funding is in place to conduct research into the human health or ecological risks, monitoring, detection, innovative WWTP removal processes and the structuring of a responsive regulatory response.

Without research for detection and monitoring, and risk assessment to study the quantities and impacts of CEC discharged into freshwater sources, there is no way of knowing what the long-term consequences will be. Regulations can drive the innovation in technology and the removal of CEC from waste streams.

Policy implications

  • All levels of government and the wastewater industry are unprepared to address CEC pollution that has been identified as a ubiquitous pollution problem affecting the human health of Canadians and ecosystems within the biosphere.
  • In order to recognize the lack of political will demonstrated by all levels of government to address not only sources of CEC pollution but also the lack of modernization of WWTPs, CEC regulatory tools (production, use or disposal) could be developed and directed at the source (e.g., industrial, commercial and public sector sources) with the goal of preventing CEC discharges into municipal sewers. 
  • A regulatory risk exists for sectors of the economy that manufacture, produce and dispose of CEC into municipal sewer systems or directly into receiving waters without first treating effluent discharges from their facility.
  • An opportunity exists to become a first mover in the development of innovative WWTP processes that eliminate CEC from discharge streams and advance the use of artificial intelligence methods in support of a circular economy.
  • Funding opportunities are needed, perhaps developed through public-private partnerships that are directed at research and development in WWTP processes that address CEC pollution.

Further information

Read the full report

Contact the researchers

Kim Gilbride, Professor, Department of Chemistry and Biology, Ryerson University; gilbride@ryerson.ca

Rania Hamza, Assistant Professor, Department of Civil Engineering, Ryerson University; rhamza@ryerson.ca

Patricia Hania, Assistant Professor, Department of Policy and Law, Ryerson University; rhania@ryerson.ca

The views expressed in this evidence brief are those of the authors and not those of SSHRC.

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