(WO9625222-A1)      Packing materials for use in units for biological treatment of waste air comprise an organic material (I) pelletised with an organic material (I) pelletised with an organic binder (II).    Also claimed is the prodn. of such materials by mixing (I) and (II) and pressing the mixt. into pellets while curing the binder.    Pref. (I) is peat, heather and/or compost,(II) is an aminoplast or phenoplast resin, esp. urea-formaldehyde, and is present in an amt. of 10-50 wt.%.    USE -   The materials are useful in units for bioconversion of pollutants in waste air from industrial plants, e.g. lacquering or printing works.    ADVANTAGE -   The pellets have good mechanical stability and moisture resistance while retaining the properties of (I) as a moisture reservoir and microbial nutrient source. Being biodegradable, they can be disposed of by composting.    (EP809530-A1)      Packing materials for use in units for biological treatment of waste air comprise an organic material (I) pelletised with an organic material (I) pelletised with an organic binder (II).    Also claimed is the prodn. of such materials by mixing (I) and (II) and pressing the mixt. into pellets while curing the binder.    Pref. (I) is peat, heather and/or compost,(II) is an aminoplast or phenoplast resin, esp. urea-formaldehyde, and is present in an amt. of 10-50 wt.%.    USE -   The materials are useful in units for bioconversion of pollutants in waste air from industrial plants, e.g. lacquering or printing works.    ADVANTAGE -   The pellets have good mechanical stability and moisture resistance while retaining the properties of (I) as a moisture reservoir and microbial nutrient source. Being biodegradable, they can be disposed of by composting.    (JP11501862-W)      Packing materials for use in units for biological treatment of waste air comprise an organic material (I) pelletised with an organic material (I) pelletised with an organic binder (II).    Also claimed is the prodn. of such materials by mixing (I) and (II) and pressing the mixt. into pellets while curing the binder.    Pref. (I) is peat, heather and/or compost,(II) is an aminoplast or phenoplast resin, esp. urea-formaldehyde, and is present in an amt. of 10-50 wt.%.    USE -   The materials are useful in units for bioconversion of pollutants in waste air from industrial plants, e.g. lacquering or printing works.    ADVANTAGE -   The pellets have good mechanical stability and moisture resistance while retaining the properties of (I) as a moisture reservoir and microbial nutrient source. Being biodegradable, they can be disposed of by composting.