The Accident

A truck spilled a portion of its cargo off Daysville Bridge onto the shoreline and into Daysville River. Overall, 5,000 G (18,750 Liter) of a nano pesticide in solution were spilled (equivalent to 16,500 lb or 7,500 kg of Nano-[Ag]-cide® product).
1000 ft. (300 m) from Daysville Bridge is the popular Daysville Beach and Boat Launch.
About 3000 ft. (900 m) from Daysville Bridge is a large Drinking Water Intake and Filtration Plant serving 1.8 million residents.
About 5 miles (8 km) from Daysville Bridge are commercial and recreational fisheries for the precious DC Freshwater Shark.

Environmental conditions: 82°F/28°C; mid-morning, weekday, overcast, gusty winds up to 20 miles/hour (30 km/hr) from the West.

River conditions: Flow velocity 3 ft/s (0.9 m/s) and total river flow volume of 150,000 ft3/s (4245 m3/s).

Product Details


The fictitious Nano-[Ag]-cide is a 30 % (wt/wt) suspension of a silver-silica hybrid particle. The product is provided in 20 and 200 liter drums and 1040 liter tote tanks. For the purpose of the scrimmage, we will be assuming that eighteen (18) 1040 liter tote tanks are involved, representing 5,000 gallons (18,750 liters). The packaging, solids content and pH (> 10) are very similar to silica slurries used for chemical mechanical planarization. The product is registered for site remediation, where the silica component acts as a proppant to keep channels open, which allows for the silver component to be accessible for microbiological control.

The particle is a silica-silver hybrid where the silver is present as 20 nm diameter spheres manufactured using a citric acid as a capping agent and strongly adsorbed onto the 2 surface of a 300 nm precipitated silica gel particle using a proprietary low molecular weight polyethyleneimine. The silver content is 10% wt/wt relative to silica.

Amount spilled as product:24 tons
Amount spilled as solids:7.5 tons
Solids composition:10% silver/ 90% silica

1 ton is 1,000 kg or 2,200 lb.

Potential Press Conference Questions

The charge for the COR teams is to prepare a response to the hypothetical “Daysville” spill scenario for a press conference, with the audience of media, NGO representatives, and public citizens. The intent is to engage in a fun and creative manner to transcend our disciplines and habits of communication, and challenge our research community to ask ourselves: what does our collective nanoEHS knowledge allow us to say, specific to nanomaterials, in response to a hypothetical real-world scenario?

Teams will each prepare a 5-minute oral response (no PowerPoint) citing what they believe are the most important issues to discuss with respect to the potential exposures and hazards associated with the event.

After all teams have presented their prepared remarks, each team will send 1-2 representatives forward to participate in the mock question/answer portion of the briefings. The questions will be delivered by stakeholder representatives, and will be chosen such that they are highly relevant to the nanoEHS subject matter expertise as opposed to an emergency response focus.

Broadly speaking, they are likely to inquire about:

  • What was spilled?
  • Where is it? In the river? The banks? How long will it be there?
  • Is it dangerous for my pet to drink the water? Or to drinking water?
  • What are the risks we should worry about?
  • What is the difference between a regular pesticide and a nanopesticide?

Press Conference – nanoAg slurry spill on the riverbank

Stakeholders: Media, NGOs, concerned members of the public

Example questions:

  • Can we fish in the bay?
  • How does this material impact drinking water quality and the ecosystem?
  • Will our drinking water plants be compromised or can they handle this – can we drink our tap water?
  • How does it behave in the water?

Context Beyond Our nanoEHS Research Focus(i.e. Important but not in our scope)
Broader list of potential questions in response to an incident involving nanomaterials


A supporting set of reference resources for participants to utilize for the scrimmage and related actions.