Colloidal gel as an efficient process to treat Chemical, Biological, Radiological (CBR) and prion contaminated solid surfaces

[Display omitted] •CBR contaminations on solid surfaces were removed using a vacuumable gel.•CBR contaminants are absorbed by the gel and remain trapped as it dries.•Biological and chemical agents are neutralized by hypochlorite ions and NaOH.•A 7.3-log reduction of Bacillus anthracis CFU is reached with the CBR gel.•The secondary solid waste produced is easily removed and of low toxicity. Chemical, biological, radiological and nuclear (CBRN) accidents or attacks typically disseminate contaminants inside and outside buildings and structures whose surfaces have to be decontaminated. This paper describes an innovative colloidal gel formulation and its effects against CBR threat agents and prion contaminations. The gel’s rheological properties ensure it remains attached even to vertical surfaces. The gel then dries with the contaminants trapped inside, leaving behind non-dusting solid residues that are easy to recover by brushing or vacuum cleaning. The results obtained here on different formulations show that decontamination proceeds in two steps. Contaminants are first solubilized or absorbed into the gel thanks to the efficient wetting of the surface by the gel. Chemical and biological agents are then neutralized by the NaOH and hypochlorite ions in the gel. This article demonstrates the efficiency of this CBR gel against Bacillus anthracis, sulfur mustard, VX, soman, 137Cs, and prion proteins.