Environmental Science: Carcinogens and Soil Standards

Substances that can cause cancer by damaging DNA and promoting abnormal cell growth.

A specific chemical that directly triggers cancer development.

A substance that is not carcinogenic on its own, but gets converted into a carcinogen in the body.

A substance that doesn't directly cause cancer but enhances the effects of other carcinogens.

A substance that accelerates the growth of cancer cells.

Toxic effects that are not related to cancer development. They can include various health problems.

The ways in which harmful substances can enter the body.

The amount of a substance required to cause harm. Some substances are very toxic in small doses, while others require large amounts.

The dose of a contaminant that causes 50% of a test population to die.

A measure of toxicity expressed as the concentration of a substance in the environment (like water) that kills 50% of a test population.

A set of standards used to assess the potential risks associated with contaminated sites.

A system for categorizing, evaluating, and managing contaminated sites in Nova Scotia, Canada.

Numerical standards set by Nova Scotia Environment (NSE) for contaminated sites. They provide a baseline for assessing the level of contamination at a site.

Specific standards developed for different pathways (e.g., soil, groundwater) of contaminant exposure. They provide tailored evaluations.

A group of experts who provide scientific advice and guidance on the development and implementation of environmental quality standards for contaminated sites.

The document that outlines the rationale and background for the development and implementation of environmental quality standards in Nova Scotia.

Environmental Quality Standards (EQS) for contaminated sites in Nova Scotia (NS) are developed using a comprehensive approach that considers various factors, including the type of environmental media affected, potentially harmful contaminants, land use and activities, soil texture, and exposure pathways.

The environmental media relevant to EQS in NS include soil, groundwater, surface water (both freshwater and marine), and sediment. These media represent the potential pathways for contaminant transport and exposure to receptors.

A Master List of Potential Contaminants of Concern (CoCs) has been developed for all media of interest in NS. This list is based on experiences at contaminated sites in NS and references benchmarks used in other Canadian and US jurisdictions. It's important to note that the presence and significance of CoCs need to be assessed for each specific site.

The Chemical Abstracts Service (CAS) Registry Number, or CAS RN, is a unique numerical identifier assigned to every chemical substance described in scientific literature. It's a crucial tool for cataloging, tracking, and identifying chemical substances.

Land use classifications in EQS for contaminated sites in NS consider the frequency, duration, and intensity of exposure for human and ecological receptors based on the nature of the land use, activities associated with it, and accessibility of site media.

Exposure pathways describe the ways in which contaminants can enter the body of human and ecological receptors. Understanding these pathways is crucial for assessing potential risks and developing appropriate remediation strategies.

The absence of an applicable standard for a specific exposure pathway in Tier 1 or Tier 2 tables indicates that there is currently no established guideline for the contaminant in that context. This does not necessarily mean the contaminant is safe; further investigation and risk assessment may be required.

The exposure frequency, duration, and intensity for receptors are related to the land use classification, activities, and accessibility of site media. This means that the intensity of exposure to a contaminant may vary depending on how the land is used and how easily people and wildlife can interact with it.

A physical property used to classify soil based on particle size. Fine-grained soils have more particles smaller than 75 microns, while coarse-grained soils have more particles larger than 75 microns.

Industrial properties often have restricted access, limiting exposure of the general public and ecological receptors to contaminants.

Soil classification based on particle size, where greater than 50% of the soil by dry weight has particles smaller than 75 microns in diameter.

Soil classification based on particle size, where greater than 50% of the soil by dry weight has particles larger than 75 microns in diameter.

The specific routes by which contaminants enter the body.

A group of guidelines used to set standards for the acceptable levels of contaminants in the environment.

A risk level of 1 in 100,000 for cancer development.

The process of adjusting the target risk level for carcinogens to ensure consistency across different jurisdictions.

The principle that the lowest of two standards, whether for ecological or human health, should be used for setting the final guideline.

A simpler approach to assessing contaminated sites, using pre-defined values and requiring minimal site-specific information.

A more customized approach, using site-specific data to tailor standards for different contaminant exposure pathways.

A way to assess the environmental impact of contaminants, categorized by land use and soil texture, providing standardized values.

When site contamination exceeds Tier 1 EQS, Tier 2 PSS offers more specific standards, allowing for tailored site management approaches.

They aim to ensure human health and ecological protection, with the same level of protection regardless of the chosen standard.

They differ in the amount of site-specific information used to assess contamination and the management practices implemented.

Tier 2 PSS allows for flexibility in managing contamination by excluding or managing specific exposure pathways with appropriate documentation and site management.

The Contaminated Sites Regulations provide the legal framework for managing contaminated sites in Nova Scotia, outlining requirements and procedures.