We have been sent a video from Alquraiya, produced by an opposition group, giving more insight into the photograph we posted this morning of protesters in front of a blanket of tear gas, after a march was attacked by security forces. The footage of the extraordinary amount of tear gas used by police on defiant demonstrators again raises concerns over police tactics and the short- and long-term health risks of exposure to such a volume of tear gas.
At EA, we hear daily accounts from people in Bahrain who experience the tear gas fired in villages and residential areas and even inside homes, but what does that mean beyond their stories?
There have been no good studies of the continued effects of tear gas on a civilian population, and manufacturers typically defend their product on the grounds that people are unlikely to be exposed to it for any length of time. (This of course assumes that tear gas is always used "responsibly" by security forces, for the sole purpose of crowd control. It is evident that it is being used in Bahrain in a very different manner.)
Beyond the Shield: Anti-Riot Operations Guide, a book published in 2011, sympathetic to the use of "non-lethal" arms, has this to say about CS (tear) gas, under the heading "Long-term Effects and Severe Medical Complications":
At higher levels of exposure, inhalation toxicology studies indicate, that CS can cause chemical pheumonitus (pheumonia), and fatal pulmonary edema (victims die by drowning in their own lung fluids). CS exposure can also lead to reactive airways (breathing) dysfunction. Oral toxicological studies note the facility of CS to cause severe gastroenteritis (intestinal irritation, and ulcers) with perforation. CS is a primary skin irritant, some individuals will develop contact dermatitis even after what appears to be an unproblematic initial exposure, and severe blistering can emerge several hours later. Any exposure to even a low concentration of CS raises blood pressure, and there is a particular risk of health damage to anyone over 30 [we would add also anybody under 18], under physical strain or having an undetected aneurysm (potential artery hemorrhage).At higher levels, CS has been associated with heart failure, heptacellular (liver) damage, and death. An US based manufacturer (Federal Laboratories), has warned that - "Firing one tear gas projectile (Federal No. 230) into a room of the size of eight-feet, by eight-feet by seven-feet, could endanger the life of an average individual, if he/she stayed in the room for seven minutes." CS from canisters has also caused acude mass-chemical burns. Laboratory testing in vitro showed CS to be clastogenic, (causing disruption of chromosomes), and mutagenic (causing inheritable genetic changes in organisms). In other studies, CS showed to cause an increase in the number of abnormal chromosomes. These risks of a build up of exposure are increased because of the acquisition of tolerance to CS. A military study on the cercinogenicity (cancer causing) potential of CS was inconclusive, but observed that chronic exposure to very low concentrations is of greater concern, and should be further studied [emphasis mine].
The interesting footnote? Federal Laboraties, the American company who reported that just one cannister fired in a room could prove lethal, is one of the companies who have exported tear gas to Bahrain.