A/HRC/5/5 page 8 Because chemicals are typically stored on site at industrial facilities, if these factories are targeted it could cause a disaster similar in scale to that of the Bhopal incident which, although not linked to an armed conflict, killed thousands. Fertiliser plants are particularly at risk because of the high quantities of ammonia which are stored on location. A direct air strike on liquid ammonia can potentially kill a large number of people because of its high toxicity. During the armed conflict in Croatia, a chemical plant was struck, releasing 72 tons of anhydrous ammonia which forced the evacuation of 32,000 residents of a nearby town.19 Furthermore, there is concern that the bombing of industrial facilities, which by their day-to-day operations already affect the environment, will further aggravate those pre-existing problems. 15. The targeting of petrochemical facilities also poses a serious threat to the environment because of the sheer number and volume of chemicals which are present on site. For example, in the case of the HIP Petrochemija complex in Pančevo in northern Serbia, which was the object of two air strikes in 1999, several toxic substances were released, including the leakage of 2,100 tons of 1,2-dichloroethane and 8 tons of metallic mercury and the burning of 460 tons of vinyl chloride.20 Dichloroethane contamination is a source of concern because it is classified as a possible human carcinogen. In addition, it is highly mobile in the ground and can easily seep into the groundwater and remain present for up to 30 years. Groundwater samples around Pančevo indicate concentrations several thousand times the 5 microgram per litre limit established by the regulations of the Environmental Protection Agency (EPA) of the United States. Mercury is a highly toxic metal and when released into the environment it can be transformed into a toxic organic form, methyl mercury, which builds up in the food chain, notably through fish. Finally, the burning of vinyl chloride, which is a confirmed human carcinogen, would release highly toxic dioxins, hydrochloric acid, carbon monoxide, and polyaromatic hydrocarbons. 16. Although the use of chemical weapons is prohibited, there have been cases in which industrial chemicals were used as weapons in armed conflicts. These cases involve the release into the environment of a non-weaponized chemical substance in order to hamper the opponent’s military operations. Documented cases indicate that such use of chemicals is in general opportunistic in nature.21 Indeed, often the temptation to use industrial chemicals in military operations will arise when these dangerous products are already present and available in an area in which military operations are taking place. The widespread use of chemicals in industrial operations and the fact that contemporary conflicts are fought in or near population centres, heightens the probability that parties to an armed conflict will come across dangerous chemicals that they could use. Documented cases further indicate that, in general, it is irregular armed forces that will have the tendency to use or threaten to use industrial chemicals against a militarily superior opponent. The potentially adverse effects on life and health of the use of such dangerous products will depend on the toxicity of the product used, the quantities released into the environment and the proximity of population centres. 19 Theodore Karasik, Toxic Warfare (RAND, 2002). 20 UNEP, The Kosovo Conflict - Consequences for the Environment and Human Settlements (1999), p. 31. 21 Theodore Karasik, Toxic Warfare (RAND, 2002).