By Stephanie Meulenbelt, National Safety and Security Scientist, Netherlands National Institute for Public Health and Environment
The food supply chain can be compromised by different factors, including intentionally. Numerous sources describe that it is particularly vulnerable to attacks with chemical, biological, radiological or nuclear (CBRN) agents, emphasize the ease with which such an attack may take place or underline their potential to create mass casualties. This contribution highlights some findings of my recently published assessment of this threat, which was based on three parameters: type of agents capable of yielding damage; possible points of introduction; and potential consequences of intentional food chain contamination.  I concluded that conducting a systematic attack on the food chain with potential to create mass casualties across a wide geographic area is actually much more difficult than generally believed. Nevertheless, the sole suspicion of food being contaminated can cause serious harm.
Type of Agents Capable of Causing Major Damage
Not all CBRN agents are easy to obtain or use, or have the potential to yield effects when introduced into food or water supplies. For example, although certain household, agricultural or industrial chemicals, such as rat poison or pesticides, are often widely available and do not need complicated weaponisation steps before use, it is not likely that they will create mass casualties if added to food. Certain biological agents are also easy to come by as they may be present in the environment, for example, when a disease is endemic. A successful biological contamination may have effects that are more devastating, not in the least because of the agents’ ability to reproduce. Luckily, effective dispersion of such agents proofs to be extremely challenging. Recorded cases of radiological contamination of food or water sources include targeted, small-scale poisonings rather than attempts to create mass casualties, and the culprits worked in environments where such materials were at their disposal.  Finally, there are no examples of nuclear contamination of food or water supplies, though an unconfirmed case of plutonium being put in the New York City’s water reservoir exists. 
Possible Points of Introduction in the Food Chain
CBRN agents can be introduced into the food system during different phases: production (farms, fisheries), processing (food factories), distribution (transport, storage) and preparation (stores, restaurants, at home). If actors are able to contaminate food early in the chain, it could potentially have widespread impact, as one could make use of the system’s distribution capacity. Yet, the earlier in the chain an agent is introduced, the more an actor is dependent on processes that are not (entirely) within his control. Processing steps will likely make an agent less toxic, though the possibility of it getting more poisonous cannot be dismissed. One would need inherent knowledge of the food chain’s working to get insight into these processes, but also have access to vulnerable parts to bypass quality and security checks to successfully contaminate supplies. Introducing CBRN agents during preparation or serving phases is easier. This is also where most intentional food contamination cases can be found. Rather than large-scale damages though, such attacks will likely cause local impact.
Potential Consequences of Intentional Contamination
A review of past incidents demonstrates that episodes of intentional food contaminations can be serious, but they rarely result in mass fatalities. Economic damage is more likely to occur. Millions of dollars lost as a result of import restrictions and destruction of (suspected) contaminated food products are no exception. For example, in 1989, when two punctured grapes containing cyanide were found in Chilean grapes after an anonymous phone call, an embargo on all fruit from Chile was announced, resulting in orders around the world being cancelled and tons of fruit being destroyed. 
During the 2011 EHEC outbreak in Germany, it took some time before the source was identified (sprouts). Initially, Spanish cucumbers were blamed and the entire Spanish fruit and vegetable sector suffered needless consequences. Such cases suggest that malicious people do not need to conduct a complicated, systematic attack on the food system to cause serious consequences. Spreading a rumour or creating suspicions of a potential CBRN contamination could already be severely disruptive, especially if it is improperly assessed and answered with a disproportionate response.
About the Author
Stephanie Meulenbelt (MA, LLM) is a researcher at the Centre for Environmental Safety and Security, National Institute for Public Health and the Environment (RIVM) in the Netherlands and part of RIVM’s (CBRN) response team. Threat analyses and risk assessments are part of her work, which focuses on (inter)national security topics.