Interestingly,the only significant environmental release for polyfoam cups is pentane,a blowing agent.On the other hand,production of paper requires extensive use of inorganic chemicals and large amounts of water effluents .Furthermore,recycling seems to favor polyfoam cups.Finally,ultimate disposal,at least in landfills,tends to favor paper cups because of their biodegradability.Yet, this advantage is called into question by recent studies indication that biodegradable materials in anaerobic landfills remain undegraded over relatively long periods of time.From the viewpoint of a variety of environmental impacts,perhaps polyfoam cups are better than paper cups!