Kerosene

Kerosene is oil that is distilled from shale oil or petroleum. Kerosene is used a denaturant for alcohol and as a fuel for heating and cooking appliances. Kerosene appliances pollute the room with harmful chemicals like carbon dioxide, sulphur dioxide, and nitrogen dioxide, which pose health risks, especially to pregnant women, asthma sufferers, the elderly, and children. Kerosene heaters should only be used in large areas with adequate ventilation.

KNO3 (potassium nitrate)

KNO3 is a natural, solid source of nitrogen. It is used to make fireworks, fertilizers, and rocket propellants. When KNO3 is ingested, it can be metabolized into potassium nitrite, which is toxic and harmful to health, especially for children.

Kcl (potassium chloride)

Kcl is a metal halide salt made of potassium and chlorine. The majority of kcl is used to make fertilizers, but the chemical is also used in food processing, medicine, and scientific applications. In excess, kcl is toxic; high doses of the chemical can lead to cardiac arrest and death.