Residents of Waukegan have heard quite a bit lately about the frightening health and cancer risks of ethylene oxide (EtO). However, they have heard very little about the explosion hazards of EtO. We would be naive to ignore these very real hazards and the risks they pose for our community—especially since Waukegan was literally shaken by a major explosion of another type of chemical facility, the AB Specialty Silicones factory, on May 3, 2019.

EtO explosions are lethal

In addition to its many industrial uses, EtO and, in some cases, propylene oxide (PO) are the main components in thermobaric and fuel air explosive (FAE) weapons used by the US military. These are among the most powerful nonnuclear weapons in our country’s arsenal. Thermobaric weapons are two-phase explosives: They first create an aerosol cloud of flammable material and then ignite it, similar to a gas leak or a coal mine explosion.. They can wound or kill via multiple mechanisms—the blast wave, exposure to burning fuel, or exposure to the residual fuel cloud.

EtO is a preferred fuel for these weapons as it has a shock wave effectiveness of 5:1 compared to dynamite,[1] according to Explosives by Rudolf Meyer et al. In other words, to duplicate the shock wave of 5 pounds of dynamite, you need just 1 pound of EtO.

Thermobaric weapons fueled by EtO react at a very high temperature and cause a self-sustaining flame, setting fire to all structures in the immediate blast radius. The decomposition reaction resulting from the primary explosion moves at nearly 4,500 miles per hour,[1] burning as it goes.

“Those near the ignition point are obliterated. Those at the fringe of explosion are likely to suffer many internal, and thus invisible injuries, including burst eardrums and crushed inner ear organs, severe concussions, ruptured lungs and internal organs, and possibly blindness,”[2] according to a 1990 CIA study.

In a 1993 document, the Defense Intelligence Agency speculated that because the “shock and pressure waves cause minimal damage to brain tissue … it is possible that victims of FAEs are not rendered unconscious by the blast, but instead suffer for several seconds or minutes while they suffocate.”[2]

“The [blast] kill mechanism against living targets is unique—and unpleasant,” according to a separate 1993 Defense Intelligence Agency document. “… What kills is the pressure wave, and more importantly, the subsequent rarefaction [vacuum], which ruptures the lungs. … If the fuel deflagrates but does not detonate, victims will be severely burned and will probably also inhale the burning fuel. Since the most common FAE fuels, ethylene oxide and propylene oxide, are highly toxic, undetonated FAE should prove as lethal to personnel caught within the cloud as most chemical agents.”[2]

EtO explosions in Waukegan? 

Why are the effects of EtO-fueled weapons relevant to residents of Waukegan? Because, according to the risk management plan (RMP 3-2172) it submitted on May 29, 2019, to the Illinois EPA, the Vantage Specialty Chemicals plant in Gurnee has 700 tons of EtO stock on hand, and 205 tons of propylene oxide.  This is enough to generate a shock wave equivalent to a 4.5-kiloton TNT explosive.

At the Medline Industries plant in Waukegan, the estimated on-site EtO stock would generate a shockwave equivalent to an 80-ton TNT explosive. However, we can only estimate the risk as Medline has not filed a risk management plan with the state. This means possible risks would be a mystery for first responders and environmental officials arriving on the scene in the event of an accident.

Using these figures, we can calculate a blast wave and damage radius for a catastrophic failure at either of these facilities.

At Vantage, the primary explosion would be a fireball almost 500 feet across. It would cause instant third-degree burns to people within 3,000 feet—including workers at ABC Supply, Dynapar, Gallagher Corporation, and more.

The pressure wave would cause most houses within a half mile to collapse. It would destroy Route 41 and any vehicles on the road. It would break all windows in a one-mile radius.

The result: approximately 1,000 casualties, with many additional injuries.

Barring an explosive event, Vantage’s own risk management plan concludes that a 10-minute leak event would cover 9.9 miles and affect 387,000 people. This radius includes schools, residences, hospitals, recreational facilities, churches, airports, wildlife sanctuaries, rivers, creeks, and even Lake Michigan. This would expose people within the zone to an environment “as lethal to personnel … as most chemical agents.”[2]

There is no passive mitigation in place to stop this gas once it has been released. Vantage’s active mitigation includes two independent computer control systems to control their processes, but there is no mention of any cybersecurity measures that would protect the public if one or both of these control systems were to become compromised.

At Medline, the primary explosion would be a fireball 100 feet across. It would cause third-degree burns to people within 700 feet, including workers at nearby facilities.

The pressure wave would destroy nearly every building within 600 feet—including an AbbVie facility, Fastenal, and Precision Laboratories—and other unreinforced buildings. It would destroy Route 41 and any vehicles on the road. It would break all windows at buildings within a quarter mile—including Candlewood Suites and Fountain Square Senior Apartments.

The result: approximately 190 casualties, with many additional injuries.

These are conservative estimates, and for Medline are based only on estimated EtO stocks.

One important caveat: These calculations are based on a circular blast radius. Due to the drifting of fuel that happens in thermobaric explosions between the primary aerosolizing event and main explosion, the shape of the blast radius is rarely so easily defined.[3]

It is also important to remember that both Vantage and Medline are located in industrial zones that house other facilities with their own stocks of flammable and explosive substances—like AB Specialty Silicones. However, determining the magnifying effects of these other chemical stocks on the tremendous devastation that would result from a failure at either Vantage or Medline is beyond the scope of this post.

EtO: Wrong for residential areas

We are not alone in this view. We know that ethylene oxide is an extremely dangerous chemical, both as an emitted gas and as a stockpiled explosive. We will continue to push to control this explosive, carcinogenic, and mutagenic substance until we can be sure that all of us, all of our children, and all of our communities are safe. We demand that right.

Dr. Dylan Burdette has a doctorate in biochemistry and molecular biology. 

References
1. Meyer R, Köhler, J., Homberg A. Explosives. 6th ed. Weinheim, Germany: Wiley-VCH; 2007. 2. Human Rights Watch. Backgrounder on Russian fuel air explosives (“vacuum bombs”). https://www.hrw.org/report/2000/02/01/backgrounder-russian-fuel-air-explosives-vacuum-bombs. Published February 1, 2000. 3. Cross K, Dullum O, Jenzen-Jones NR, Garlasco M. Explosive weapons in populated areas: technical considerations relevant to their use and effects [PDF]. Armament Research Services (ARES): May 2016. https://www.icrc.org/en/download/file/23603/aresweb-generic.pdf. Accessed June 24, 2019.

This post has been updated. An earlier version contained a quotation from a third party.