Lead

• Performance measurement evaluation
• Background

Performance measurement evaluation

Conducting performance measurement evaluations allows the Government to assess whether the risk management actions taken on substances found to be toxic under the Canadian Environmental Protection Act, 1999 (CEPA 1999) were effective in meeting risk management objectives, or whether adjustments would help to protect Canadians and their environment. The Evaluation of the Effectiveness of Risk Management Measures for Lead was published on July 3, 2020.

Background

Lead is a toxic substance under the CEPA 1999, and is found naturally in rock and soil, and is used in industry. Because of these natural and human-made sources, lead can be found throughout the environment in Canada, in air, bodies of water, and soil, as well as food and drinking water.

The main route of exposure for the general adult population is ingestion from food and drinking water, followed by inhalation. In addition, individual exposure from other sources may be significant. For example, inhalation is an important route of exposure for individuals living in the vicinity of point sources, that is, an identifiable local source of lead, such as an industrial stack. As well, the behaviours of infants and children include crawling, greater frequency of hand-to-mouth contact, and a tendency to eat non-food items such as soil or paint. Therefore, for this age group, ingestion of non-food items contaminated with lead such as household dust, lead-based paint, soil, and consumer products, along with dietary intake through food and water, are the greatest sources of environmental exposure to lead.

Additional sources that may also contribute to lead exposure for the general population include ingestion of wild game harvested using lead ammunition, and oral intake from certain products that could contain lead such as lead crystalware or art supplies. Buildings with deteriorating lead-based paint or lead service lines/water pipes, or that are being renovated may also be a source of lead exposure. Particular occupational (that is, firearms use) and recreational activities (that is, stained-glass making), ingestion of vegetables grown in lead-contaminated soils, and behaviours such as smoking may further increase exposure to lead.

Lead poses significant risks to the environment and human health. In humans, exposure to lead is associated with harmful effects on the brain, heart, and kidneys, and to reproduction. While lead can be harmful to people of all ages, infants and children, and pregnant women and the fetus, are especially susceptible to lead exposure. Infants and children are particularly susceptible to the neurodevelopmental effects of lead exposure because of their developing brains. Lead has also been shown to be toxic to birds, fish and aquatic life, invertebrates, plants, and animals that live in soil.

Therefore, over the past decades, the Canadian federal government has taken numerous actions to minimize or eliminate lead exposure in order to protect the health of Canadians and their environment from the harmful effects of this substance. This has involved regulatory and other measures focusing on mining, base metals smelting and refining, steel manufacturing, various products used by consumers, drinking water, food and environmental media, including household dust, soil and air. In order to determine the effectiveness of these measures, the government has conducted a performance measurement evaluation and summarized the progress toward risk reduction in the Evaluation of the Effectiveness of Risk Management Measures for Lead, published in 2020.