Hydrazine - information sheet

CAS Registry Number 302-01-2

Updated November 10, 2018:

The Final Screening Assessment for Hydrazine was published on January 15, 2011 under the Challenge initiative of the Chemicals Management Plan (CMP). The assessment is summarized in this information sheet (formerly public summary) and has not changed. The section in this information sheet entitled "Preventive actions and reducing risk" communicates updates in risk management activities, namely:

• Publication of the pollution prevention planning notice

On this page

• Overview
• About this substance
• Exposure of Canadians and the environment
• Key health and ecological effects (hazard)
• Risk assessment outcomes
  • Screening assessment conclusions
• Preventive actions and reducing risk
• Important to know

Overview

• The Government of Canada conducted a science-based evaluation, called a screening assessment, of hydrazine to address the potential for harm to Canadians and to the environment.
• Under the Canadian Environmental Protection Act, 1999 (CEPA 1999), the risk posed by a substance is determined by considering both its hazardous properties (its potential to cause adverse human health or ecological effects) and the amount of exposure there is to people or the environment. A substance may have hazardous properties; however, the risk to human health or to the environment may be low depending on the level of exposure.
  • More information on assessing risk can be found in the Overview of Risk Assessment and related fact sheets, particularly on Types of Risk Assessment Documents and the Risk Assessment Toolbox.
• As a result of the screening assessment, hydrazine was concluded to be harmful to human health and to the environment, at levels of exposure at the time of the assessment.

About this substance

• This screening assessment on hydrazine was done as part of Batch 10 of the Challenge initiative of the CMP.
• The Government gathers information on substances, including details on their commercial status in Canada, to support the risk assessment and management of substances under the CMP.
• Hydrazine is an industrial chemical and also occurs naturally in algae and tobacco plants.
• At the time of the assessment, hydrazine was mainly used as a corrosion inhibitor in boiler water at power generating plants.
• It also could be found in trace amounts as a residual substance (leftover from the manufacturing process) in certain polymers, which may in turn be used in cosmetics, natural health products, pharmaceuticals, food packaging materials, food additives, and also pesticides.
• Hydrazine is present in tobacco and tobacco smoke.

Exposure of Canadians and the environment

• The assessment indicated that exposure of Canadians to hydrazine was expected to be low since it was primarily used in industrial settings. Exposure could occur from the inhalation of tobacco smoke.
• Hydrazine may be released to the environment, mainly to water, with smaller amounts being released to air and soils. Releases of hydrazine to the environment were primarily associated with the operation of nuclear and fossil fueled power plants.

Key health and ecological effects (hazard)

• At the time of the assessment, the important or “critical” effects used for characterizing the risk to human health for hydrazine was carcinogenicity.
• For the ecological assessment, hydrazine was considered to have high aquatic toxicity.

Risk assessment outcomes

• As a result of this screening assessment, it was determined that hydrazine may pose a risk to human health.
• Hydrazine was not expected to remain in the environment for a long time or to accumulate in organisms. However, it was found that potential releases of hydrazine could cause harm to aquatic organisms.
• It was concluded that hydrazine does not meet the persistence and bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations of CEPA 1999.
• The Government of Canada published the Final Screening Assessment for Hydrazine on January 15, 2011.

Screening assessment conclusions

• As a result of the assessment, the Government concluded that hydrazine is harmful to human health, at levels of exposure at the time of the assessment.
• The Government also concluded that hydrazine is entering the environment at levels that are harmful to the environment.

Preventive actions and reducing risk

• Hydrazine is listed on Health Canada’s Cosmetic Ingredient Hotlist. The Hotlist is used to communicate that certain substances may not meet the requirements of the Food and Drugs Act or the Cosmetic Regulations.
• The proposed Risk Management Approach for Hydrazine was published on January 15, 2011 and had a 60-day public comment period. In accordance with the approach, the Government took the following steps to reduce or manage the risks associated with this substance.
  • Hydrazine was added to Schedule 1 of CEPA 1999, also called the List of Toxic Substances.
  • In November 2018, a notice requiring the preparation and implementation of pollution prevention (P2) plans in respect of hydrazine related to the electricity sector was published. Facilities subject to the plans are required to avoid or minimize the creation of pollutants and waste, and reduce the overall risk to the environment and to human health.
  • Applying Significant New Activity (SNAc) provisions was considered for hydrazine, however, due to its chemistry, hydrazine would only be present in a consumer product at low residual levels. As a result, and also because it is on the Cosmetic Ingredient Hotlist, there are no likely new exposure sources of hydrazine for Canadians that would reasonably be suspected to lead to increased risk to human health. Therefore, this risk management instrument is no longer being pursued.  
  • Starting with the 2014 reporting year, the National Pollutant Release Inventory (NPRI) reporting threshold was reduced from 10 tonnes to 1 tonne to capture additional potential sources of releases occurring at lower volumes.
  • Releases of hydrazine will continue to be reported to the NPRI and monitored periodically to inform decisions on potential additional risk management actions, if required, to protect Canadians and the environment.
• Further information and updates on risk management actions for substances managed under the CMP can be found in the CMP Risk Management Actions table and the Two Year Rolling Risk Management Activities and Consultations Schedule. Actions for hydrazine can also be found in the risk management action milestones for Batch 10 table.

Important to know

• Hydrazine may be present in products available to consumers as a residual substance, leftover from the manufacturing process. Canadians should follow any safety warnings and directions on product labels and dispose of products responsibly.
• Tobacco smoke is a source of hydrazine. Read how you can quit smoking now.
• Canadians who may be exposed to hydrazine in the workplace should consult with their employer and an occupational health and safety (OHS) representative about safe handling practices, applicable laws, and requirements under OHS legislation and the Workplace Hazardous Materials Information System (WHMIS).