ChemHAT health impact icons have different colors depending on the strength of the evidence. For example, when authoritative government bodies have definitively determined that a chemical cause cancer in people, the icon will be red to show that it is the strongest evidence base.
Key to Symbols
Stronger effect / evidence




Weaker effect / evidence

PBT (Persistent Bioaccumulative Toxicant) – Does not break down readily from natural processes, accumulates in organisms concentrating as it moves up the food chain, and is harmful in small quantities.

Cancer – Can cause or increase the risk of cancer.

Breast Cancer – Known to increase mammary gland tumors in animals.

Birth Defects – Can cause harm to the developing child including birth defects, low birth weight and biological or behavioral problems that appear as the child grows.

Reproductive Harm – Can disrupt the male or female reproductive systems, changing sexual development, behavior or functions, decreasing fertility, or resulting in loss of the fetus during pregnancy.

Endocrine Disruption – Can interfere with hormone communication between cells which controls metabolism, development, growth, reproduction and behavior (the endocrine system).

Gene Damage – Can cause or increase the rate of mutations, which are changes in genetic material in cells.

Asthma Trigger – Can result in high sensitivity so that small quantities trigger asthma, nose or sinus inflammation or other allergic reactions in the respiratory system.

Brain/Nervous System Harm – Can cause damage to the nervous system including the brain.

Toxic to Humans & Animals – Can be fatal on contact, ingestion or inhalation for humans and other mammals.

Other Health Effects – Can cause serious damage on contact or ingestion.

Irritates the Eyes – Can cause irritation or serious damage to the eye.

Irritates the Skin – Can cause irritation or serious damage to the skin.

Sensitizes the Skin – Can lead to allergic reactions on the skin.

Flammable – Easily ignited and capable of burning rapidly.

Reactive – May spontaneously ignite or explode on its own or in contact with water.

Restricted List – This chemical is on a list from an authoritative body recommending that its use be avoided.

Immediate Harm to Aquatic Ecosystems – A single exposure may result in severe biological harm or death to fish or other aquatic organisms.

Long-Term Harm to Aquatic Ecosystems – Long term exposure may result in irreversible harm to fish or other aquatic organisms.

Harmful to Land Ecosystems – Can cause harm to land based plants, animals or microorganisms.

Climate Change – Contributes to the greenhouse effect or traps heat in the atmosphere, causing temperature changes and contributing to climate change.

Ozone Depletion – Can contribute to chemical reactions that destroy ozone in the earth’s upper atmosphere.

Persistent – Does not break down readily from natural processes.

Bioaccumulative – Accumulates in organisms, concentrating as it moves up the food chain.