Abstract: The invention relates to a suspension of ammonium carbonate and/or ammonium hydrogen carbonate in an aqueous solution saturated with respect to said salts and optionally also containing urea. For the purpose of stabilizing the suspension there is incorporated therein a polyacrylic acid having an average molecular weight (M.sub.w) in the range of 4.times.10.sup.5 -1.times.10.sup.6, preferably about 7.5.times.10.sup.5. The invention also relates to the use of the suspension for treating carbamide-resin bound, wood-based board material, such as plywood, chipboard and wood fibreboard, for reducing the emission of formaldehyde therefrom.