The present application relates to the use of a solution for the treatment of exhaust gases at the outlet of on-board or stationary diesel engines. In one embodiment, an apparatus for sealing a substrate transfer passage in a chamber includes an elongated door member having a convex sealing face and a backside. The housing includes a mating cavity and a mating face defined on an inner bottom of the mating cavity. 1 wt % butylated hydroxy toluene dissolved in ethanol for a HaCat cell culture after 24 h incubation period.