* Dosage: Even "safe" substances can be toxic in high enough doses.
* Route of exposure: Inhalation, ingestion, or skin contact can have different effects.
* Chemical form: The same element can have different levels of toxicity depending on its chemical compounds.
* Individual sensitivity: People react differently to substances.
However, some non-metallic elements are generally considered highly toxic and dangerous:
* Polonium (Po): This radioactive element is extremely toxic, even in trace amounts. It's a potent alpha emitter, causing severe radiation damage.
* Arsenic (As): Known for its historical use as a poison, arsenic is toxic in various forms. It interferes with cellular processes, leading to organ damage and death.
* Fluorine (F): While essential in small amounts for dental health, fluorine is highly reactive and corrosive. It can cause severe burns and respiratory problems.
* Chlorine (Cl): A common disinfectant, chlorine gas is highly toxic in high concentrations. It irritates the respiratory system and can be fatal.
* Bromine (Br): This element is a strong oxidizer and corrosive. Exposure to bromine vapors can cause severe burns and respiratory problems.
Important Note: It's crucial to handle all chemicals, especially those known to be toxic, with extreme care and appropriate safety precautions.
