Fluorine is a chemical element with symbol F and atomic number 9.  It is a univalent poisonous gaseous halogen, it is pale yellow-green and it is the most chemically reactive and electronegative of all the elements. Fluorine readily forms compounds with most other elements, even with the noble gases krypton, xenon and radon. It is so reactive that glass, metals, and even water, as well as other substances, burn with a bright flame in a jet of fluorine gas. In aqueous solution, fluorine commonly occurs as the fluoride ion F-. Fluorides are compounds that combine fluoride with some positively charged counterpart.  Fluorine does not exist in nature in its elemental state. 
Fluorine is used in the petrochemical industry, aluminium manufacturing, in dye and ceramics, for etching glass and enamel, as flux for smelting and in agricultural chemicals. Atomic fluorine and molecular fluorine are used for plasma etching in semiconductor manufacturing, flat panel display production and MEMs fabrication. Fluorine is indirectly used in the production of low friction plastics such as teflon and in halons such as freon, in the production of uranium. Fluorochlorohydrocarbons are used extensively in air conditioning and in refrigeration.
In the Environment 
When fluorine from the air ends up in water it will settle into the sediment. When it ends up in soils, fluorine will become strongly attached to soil particles. In the environment fluorine cannot be destroyed; it can only change form. Fluorine that is located in soils may accumulate in plants. The amount of uptake by plants depends upon the type of plant and the type of soil and the amount and type of fluorine found in the soil. With plants that are sensitive for fluorine exposure even low concentrations of fluorine can cause leave damage and a decline in growth. Too much fluoride, whether taken in form the soil by roots, or adsorbed from the atmosphere by the leaves, retards the growth of plants and reduces crop yields. Those more affected are corns and apricots. Animals that eat fluorine-containing plants may accumulate large amounts of fluorine in their bodies. Fluorine primarily accumulates in bones. Consequently, animals that are exposed to high concentrations of fluorine suffer from dental decay and bone degradation. Too much fluorine can also cause the uptake of food from the paunch to decline and it can disturb the development of claws. Finally, it can cause low birth-weights.
Sources & Routes of Exposure
Sources of Exposure 
- The general population can be exposed to fluorine in contaminated air, food, drinking water and soil.
- People living in communities with fluoridated water or high levels of naturally occurring fluoride may be exposed to higher levels.
- People who work or live near industries where fluorine-containing substances are used may be exposed to higher levels.
Routes of Exposure 
Main routes of exposure to fluorine are:
- Skin contact;
- Eye contact
Health Effects 
Fluorine is an extremely strong irritant to all tissues it comes in contact with. It can cause injury ranging from mild irritation to caustic burns depending on the concentration of the gas at the time of exposure. It is a very severe irritant of the lungs, mucous membranes, skin and eyes. The reaction of this gas with moisture produces hydrofluoric acid. Thermal burns have been reported when fluorine gas comes in contact with the skin due to the violent reaction between the skin and the gas. Direct contact with liquid fluorine can cause frostbite. The lungs appear to be the most affected tissue. Respiratory tract irritation may progress to pulmonary oedema.
First Aid Measures
Inhalation: Remove victim to uncontaminated area wearing self-contained breathing apparatus. Keep victim warm and rested. Call a doctor. Apply artificial respiration if breathing stopped.
- Skin/Eye Contact: Remove contaminated clothing. Drench affected area with water for at least 15 minutes. In case of skin contact, wearing rubber gloves rub 2.5% calcium gluconate gel continuously into the affected area for 1.5 hours or until further medical care is available. Immediately flush eyes thoroughly with water for at least 15 minutes. Alternatively irrigate eyes intermittently for 20 minutes with an aqueous Calcium gluconate 1% solution if available. Obtain medical assistance.
- Ingestion: Ingestion is not considered a potential route of exposure.
- Delayed adverse effects possible. Prolonged exposure to small concentrations may result in pulmonary oedema. May cause severe chemical burns to skin and cornea. Treat with a corticosteroid spray as soon as possible after inhalation.
- Obtain medical assistance.
- Extinguishing media: dry powder and carbon dioxide. Do not use water.
- Exposure to fire may cause fluorine containers to rupture/explode. Fluorine reacts with water.
Exposure Controls & Personal Protection
- A risk assessment should be conducted and documented in each work area to assess the risks related to the use of the product.
- Fluorine should be handled in a closed system and under strictly controlled conditions.
- Keep concentrations well below occupational exposure limits.
- Consider work permit system e.g. for maintenance activities. Preferably use permanent leak-tight connections (eg. welded pipes).
- Systems under pressure should be regularly checked for leakages.
- Provide adequate general or local ventilation.
- Gas detectors should be used when toxic quantities may be released.
- Gas detectors should be used when quantities of oxidising gases may be released.
Personal Protective Equipment
The following personal protective equipment should be used when handling fluorine:
Eye and face protection:
- Wear goggles and a face-shield when transfilling or breaking transfer connections;
- Wear eye protection to EN 166 when using gases;
- Full-face mask recommended
- Wear working gloves and safety shoes while handling containers.
- Chemically resistant gloves complying with EN 374 should be worn at all times when handling chemical products if a risk assessment indicates this is necessary.
- Material: Neoprene
- Keep suitable chemically resistant protective clothing readily available for emergency use.
- Personal protective equipment for the body should be selected based on the task being performed and the risks involved.
- Wear working gloves and safety shoes while handling containers.
- Keep self-contained breathing apparatus readily available for emergency use.
- Use SCBA in the event of high concentrations,
- The selection of the Respiratory Protective Device (RPD) must be based on known or anticipated exposure levels, the hazards of the product and the safe working limits of the selected RPD.
- When allowed by a risk assessment, Respiratory Protective Equipment (RPE) may be used.
United States 
OSHA: The United States Occupational Safety & Health Administration has set the following Permissible Exposure Limit (PEL) for fluorine:
- General Industry: 29 CFR 1910.1000 Table Z-1 – 0.1 ppm, 0.2 mg/m3 TWA
- Construction Industry: 29 CFR 1926.55 Appendix A – 0.1 ppm, 0.2 mg/m3 TWA
- Maritime: 29 CFR 1915.1000 Table Z-Shipyards – 0.1 ppm, 0.2 mg/m3 TWA
ACGIH: The American Conference of Governmental Industrial Hygienists has set a Threshold Limit Value (TLV) for fluorine of 1 ppm, 1.6 mg/m3 TWA; 2 ppm, 3.1 mg/m3 STEL
NIOSH: The National Institute for Occupational Safety and Health has set a Recommended Exposure Limit (REL) for fluorine of 0.1 ppm, 0.2 mg/m3 TWA
Safe Work Australia: Safe Work Australia has set a Time Weighted Average (TWA) concentration for fluorine of 1 ppm, 1.6 mg/m3 for a 40-hour workweek.