Guidelines for Canadian recreational water quality: Microbiological pathogens and biological hazards: Overview

On this page

• Purpose of consultation
• Foreword
• Management of microbiological pathogens and biological hazards in recreational waters
• 1.0 Guideline values and their application

Purpose of consultation

This guideline technical document evaluated the available information on microbiological pathogens and biological hazards in recreational waters with the intent to provide regulatory authorities and decision-makers with guidance on these topics. The purpose of this consultation is to solicit comments on the proposed guidance.

The document was reviewed by external experts and subsequently revised. We are now seeking comments from the public. This document is available for a 60-day public consultation period.

Please send comments (with rationale, where required) to Health Canada via email at water-eau@hc-sc.gc.ca.

All comments must be received before November 2, 2022. Comments received as part of this consultation will be shared with the federal and provincial recreational water quality working group, along with the name and affiliation of their author. Authors who do not want their name and affiliation shared with the recreational water quality working group should provide a statement to this effect with their comments.

It should be noted that this guideline technical document will be revised following the evaluation of comments received, and the Guidelines for Canadian Recreational Water Quality will be updated, if required. This document should be considered as a draft for comment only.

Foreword

The Guidelines for Canadian Recreational Water Quality comprises multiple guideline technical documents that consider the various factors that could interfere with the safety of recreational waters from a human health perspective. This includes technical documents on understanding and managing recreational waters, fecal indicator organisms, microbiological methods for monitoring fecal contamination, cyanobacteria and their toxins, physical, aesthetic, and chemical characteristics, and microbiological pathogens and other biological hazards. These documents provide guideline values for specific parameters used to monitor water quality hazards and recommend science-based monitoring and risk management strategies. Recreational waters are considered to be any natural fresh, marine or estuarine bodies of water that are used for recreation. This includes lakes, rivers, and human-made constructions (e.g., quarries, artificial lakes) that are filled with untreated natural waters. Jurisdictions may choose to apply these guidelines to natural waters where limited treatment is provided (e.g., short-term application of disinfection for an athletic event), although applying the guidelines in these scenarios should be done with caution as indicator organisms are easier to disinfect than other disease-causing microorganisms (e.g., protozoan pathogens). Recreational activities that could present a human health risk through intentional or incidental immersion and ingestion include primary contact activities (e.g., swimming, bathing, wading, windsurfing and waterskiing) and secondary contact activities (e.g., canoeing or fishing).

Each guideline technical document has been established based on current, published scientific research related to health effects, aesthetic effects, and beach management considerations. Since responsibility for recreational water quality generally falls under provincial and territorial jurisdiction, policies and management decisions may vary across Canada. The guideline technical documents are intended to guide decisions by the responsible authorities for the management of recreational waters.

For a complete list of the guideline technical documents available, please refer to the Guidelines for Canadian Recreational Water Quality summary document available on the Health Canada website (in publication-c).

Management of microbiological pathogens and biological hazards in recreational waters

This document outlines potential health risks from exposure to pathogenic microorganisms and other biological hazards associated with recreational waters. It is intended as background information for those interested in recreational water quality and safety. Implementing a preventive risk management approach that focuses on the identification and control of water quality hazards and their associated risks before the point of contact with the recreational water user represents the best strategy for protecting public health from these hazards. This approach consists of an integrated system of procedures, actions, and tools that are applied across all identified areas of management (e.g., source protection, monitoring, hazard control, communication, consultation) to reduce the risk of human exposure to recreational water quality hazards. More details on risk management of recreational water quality are available in the technical document entitled Guidelines for Canadian Recreational Water Quality - Understanding and Managing Risks in Recreational Waters (Health Canada, in publication-d).

1.0 Guideline values and their application

Guideline values are not established for the microbiological pathogens or other biological hazards described in this document. A preventive risk management approach that incorporates procedures, actions, and tools to collectively reduce the risk of human exposure to these hazards is the preferred approach to protecting public health. Further information on this approach can be found in the Guidelines for Canadian Recreational Water Quality - Understanding and Managing Risks in Recreational Waters (Health Canada, in publication-d).

The challenges associated with the detection of pathogenic microorganisms in recreational waters are currently too great to recommend a routine monitoring program. Testing for the presence of pathogens or biological hazards in waters used for recreation should be performed only when there is epidemiological or other types of evidence (e.g., visible signs of deterioration) suggesting that this may be necessary. To protect public health, and as part of a risk management approach, recreational waters are instead monitored for fecal indicators (e.g., E. coli, enterococci), as they indicate possible fecal pollution and potentially elevated risk from enteric pathogens. Guideline values have been established for both E. coli and enterococci. Although E. coli and enterococci concentrations below the guideline values indicate an acceptable level of risk, this does not mean that all pathogenic microorganisms are absent. Further information on fecal indicators can be found in the guideline technical document on fecal indicators (Health Canada, in publication-b). Non-enteric pathogens (e.g., naturally occurring or free-living organisms) are not related to fecal contamination and therefore the presence of fecal indicator organisms is not associated with the presence of non-enteric pathogens. Fecal pathogens are considered to pose a higher risk than non-enteric pathogens in recreational water settings.

In general, areas used for recreational water purposes should remain as free as is practical from pathogenic microorganisms and other biological hazards. Engaging in recreational activities, including swimming, splashing and other water activities, will always involve some level of risk. Public health decisions should balance the potential increased health risks with the enjoyment and exercise that is associated with these activities. Primary contact recreational activities should not be pursued in waters where the responsible authority deems that the presence of pathogenic microorganisms and other biological hazards poses an unacceptable risk to health and safety.

The purpose of this guideline technical document is to provide regulatory and management authorities with information on some of the microbiological pathogens and biological hazards that may exist in Canadian recreational water settings. It is based on current knowledge. However, the detection and characterization of known and emerging pathogens is a rapidly evolving field. The list of pathogens presented is not intended to be exhaustive, and responsible authorities may wish to provide information on other organisms depending on regional interests. The listed pathogens are not present in all recreational settings, nor are they present on a continuous basis. Water quality in most recreational environments varies from day to day, but also within any given day. Information on cyanobacteria (also known as blue-green algae) is not included in this document but can be found in the Guidelines for Canadian Recreational Water Quality – Cyanobacteria and their Toxins technical document (Health Canada, 2022b). Additional information on many of these organisms can also be found in the technical documents for the Guidelines for Canadian Drinking Water Quality (Health Canada, 2019a, b, 2022a).