There are three main types of commonly used fuels that are referred as lighter fuels. In transparent liquid form the butane gas is used in cigarette lighters. To be functional it must be in pressurized form. It is the gas released by it that catches fire. Because of being under pressure the butane in cigarette lighters is in liquid form. Commercial grade butane is also referred as liquid petroleum gas (LPG). It is mixed with gasoline and for higher chemical compounds it is used as a base. About 20 or 30 years ago butane was regularly used in underarm spray deodorants and in cleaning products used in homes that were available in aluminum can and used propellants.
In the category of lighter fuel the second one is naphtha. Generally it is used in camp stoves and also used in chemical sprays as a solvent. These cleaning products are preferred for metals because there is no staining or corrosion. Naphtha is also found in some lacquers and resins. This chemical is behind the distinctive smell found in shoe polish. Lighter fluid based on naphtha is used by some fire-eaters because it burns safely and cleanly.
For grilling there are briquettes that use lighter fluid. Each brick of charcoal is saturated and for this reason many people consider it as a lighter fluid. The burning of charcoal takes place only at high temperature. A special fluid solvent is used to soak the charcoal bricks for its easier burning. About a century back in fuel trains and furnaces, lump charcoal was used. For combustion it requires higher level of heat and also takes longer to light up, but keeps burning for a long time. One can say that one of the original lighter fluids was lump charcoal. Compared to wood it kept burning much longer and was readily available. Charcoal is basically another form of oil in compressed form mixed with minerals.
When using lighter fluid for general use like cooking, there are some health risks that a user must be aware of. These fuels are available in transparent form. Some compounds of the lighter fluid used for cooking may get mixed up with the food. There is no breakdown of hydrocarbons. Also no combustion of hydrocarbons takes place at normal temperatures used in grilling. At low levels it can be undetectable and tasteless. Repeated and high exposure to hydrocarbons is known to pose cancer risks.
Similar to its crude state the lighter fluids are as toxic in gas and liquid states. Many of the chemicals found in petroleum products are fat and water soluble. Over time many people suffer cancer because of exposure and ingestion of these chemicals. When the oil price rises, the cost of household lighter fluids also goes up.