The environmental impacts of plastic bag use include:
Danger to animal life, especially when they find their way into the sea.
Plastic bags are quite commonly mistaken for food by animals, especially when the bags carry food residues, are brightly coloured or are animated by the movement of water. A great variety of animals, land and especially marine, can choke to death on bags, experiencing much pain and distress. If swallowed whole, animals may not be able to digest real food and die a slow death from starvation or infection.
Pacific Trash Vortex
The amount of floating plastics in the world’s oceans is increasing dramatically. The Pacific Trash Vortex is a 'gyre' or vortex of marine litter in the North Pacific Ocean. The vortex is characterised by exceptionally high concentrations of suspended plastics, such as plastic bags, bottles, containers and other debris, that have been trapped by currents. It is now estimated to be twice the size of Texas. Its impact on marine ecosystems is catastrophic due to its toxic nature and threat to marine life.
Plastic bags are a highly visible, ugly component of litter. Local and State Governments around Australia spend more than $200 million per year picking up litter. If plastic bags continue to be used, the number of bags littering the environment will increase over time.
Loss of resources
Plastic bags are typically used for a short period of time but take hundreds of years to break down in landfill. While plastic bags can be recycled, only a tiny proportion of plastic bags are collected and reprocessed.
Based on using ten lightweight plastic bags per week over a 2-year period, the greenhouse gas impact has more than three times the greenhouse gas impact of a reusable ‘green bag’.
A lightweight plastic bags consumes about 4.5 times more energy in its manufacture than reusable ‘green bags’.
Remember, however, that to get the full greenhouse gas benefit from a reusable ‘green bag’, it must be reused over 100 times.
Starch-based biodegradable (or ‘compostable’) bags consume less than one-third of the energy to produce as plastic alternatives, but emit marginally more carbon dioxide (CO2 - a greenhouse gas) as they decompose. However, unlike single use plastic bags, biodegradable bags will completely breakdown.