Dr. Dmitri Kopeliovich
Halogenated solvent is an organic solvent, molecules of which contain halogenic atoms: chlorine (Cl), fluorine (F) , bromine (Br) or iodine (I).
Chlorinated solvents are the most popular halogenated solvents.
They may affect central nervous system, kidneys and liver, cause dermatitis and irritation of skin, eyes, upper respiratory tract and mucous membranes.
Over-exposure in poorly ventilated space may lead to depression, headache, sleepiness, unconsciousness and even death.
Some chlorinated solvents cause cancer in rats and mice at high exposure levels.
According to the National Institute for Occupatuional Safety (NIOSH), National Toxicology Program (NTP), International Agency for Research on Cancer (IARC) and American Conference of Governmental Industrial Hygienists (ACGIH):
- Trichlorethylene is a suspect carcinogen;
- Perchlorethylene is not classified as carcinogen;
- Methylene chloride is a potential carcinogen (ACGIH);
- Carbon tetrachloride is a suspect carcinogen, carcinogen Cat. 3 (ACGIH);
- Chloroform is a suspect carcinogen;
- 1,1,1-Trichloroethane is not listed as carcinogen.
Vapors of chlorinated solvent degrade in the atmosphere for a period between one week (trichloroethylene) to 5-6 months (perchlorethylene and methylene chloride).
Ozone Depletion Potential (ODP) of carbon tetrachloride and chloroform is high (more than 0.2) and their use is forbidden. ODP of trichlorethylene, perchlorethylene and methylene chloride is low and they are not regulated by the Montreal Protocol.
Spillage of chlorinated solvents to soil or water cause contamination. Methylene chloride is biodegradable. Other chlorinated solvents degrade only after reavaporation to the atmosphere.
Contributions of chlorinated solvents to global warming, acid rain production and smog formation are low.
Inhaling brominated solvents may cause dizziness, weakness, depression, headache, sleepiness.