Ministers are planning new laws to make it illegal to throw litter out of cars on Scotland's roads.
Some 1,300 bags of rubbish, weighing almost seven tonnes, are collected from the sides of the M8 and M9 each month.
New rules making it an offence to litter from vehicles is to be included in a new circular economy bill.
Environment Secretary Roseanna Cunningham said "mindless behaviour" from drivers dropping litter creates a "significant cost to the taxpayer".
The government is also working on a "national litter strategy", to be implemented "as soon as possible", and a deposit return scheme to encourage recycling.
Ms Cunningham said:"Squads of litter pickers are out on our road network every single day collecting bottles, crisp packets, cans and more, but are facing an uphill battle in the face of mindless behaviour from those motorists and passengers who are choosing to throw their litter out of the window rather than binning or recycling empty packaging at the end of their journey.
"Scotland is a beautiful country that is being blighted by litter. Not only is littering from vehicles completely unnecessary, it is unsightly and it presents a danger, both to other motorists and to the operatives leading the clean-up operation. There is also a significant cost to the taxpayer, taking valuable resources away from other public services."