Neha Sinha Posted: Jan 21, 2009 at 0039 hrs IST New Delhi: The Department of Environment has sought a customs duty waiver or VAT exemption for biodegradable plastic bag manufacturers. This follows the recent Government notification of a blanket ban on plastic bags at major shopping areas in the city. Biodegradable plastic bags of thickness up to 40 microns have, however, been allowed in minor shopping areas. A major concern voiced by shopkeepers