A material is considered harmful when it possesses properties that pose a risk of injury, illness, or environmental damage. Specifically, materials are harmful if they are toxic, poisonous, radioactive, flammable, explosive, corrosive, or reactive, and can cause harm through exposure such as skin contact, inhalation, ingestion, or environmental contamination. Harmfulness also depends on factors such as the dose, duration of exposure, and how the material interacts with the body or environment.
When Materials Are Harmful
- Materials are harmful if they cause injury, illness, or death due to their chemical or physical properties, such as being corrosive, poisonous, or reactive.
- Harm can occur through different routes of exposure including skin contact, inhalation of vapors or dust, or ingestion.
- The presence of warning labels like "corrosive," "flammable," or "toxic" indicates potential harm.
- Harmfulness also depends on the quantity and duration of exposure, and the material's ability to accumulate in the body or environment.
Factors Determining Harmfulness
- Toxicity: The inherent ability of a material to cause harm at certain exposure levels.
- Exposure Route: Inhalation, skin contact, ingestion, or eye contact.
- Dose and Duration: How much and how long a person or environment is exposed.
- Chemical and Physical Properties: Corrosiveness, flammability, radioactivity, explosiveness.
- Environmental Impact: The potential to cause pollution or contamination.
In summary, a material is harmful when its properties or behaviors cause injury or adverse health effects directly or indirectly through exposure pathways, or when it poses a hazard to the environment or safety.
