Litter and illegally dumped waste can severely impact land and land uses. For example, abnormal concentrations of heavy metals, hydrocarbons, nitrogen, solvents and gasoline can be toxic in soils, adversely affecting plant growth, soil microbial diversity and activity. Even old mattresses can contain chemicals, such as formaldehyde, that can leach into soils.
In 2018 – 19, approximately 7,400 tonnes of tyres were illegally dumped in Australia, often in forests and isolated areas. Tyres consist of carbon, steel and oil which can leach into soils. Car tyres can also shed plastic, often in the form of microplastics. The effects of leaching from dumped tyres are not well understood and require further investigation.
Cigarette butts continue to be the most littered item in Queensland. The Queensland Government commissioned comprehensive data collection and analysis of littered waste (other than cigarette butts) before and after the introduction of the container refund scheme. Beverage containers, straws and takeaway containers and takeaway containers were the most consistently littered items.
The issue of microplastics in soils and other terrestrial systems is only just beginning to be addressed. However, there is evidence that soils may represent the largest global reservoirs of micro plastic, including nanoplastic. The significance of this finding is immense, as soils present many potential ways of exposing wildlife and humans to microplastics and nanoplastics.
Plastics in soil can come from many sources, including microplastics in waste water, microplastics that blow off landfill sites and mulched plastic on agricultural fields.
Last updated: 10 May 2021
This page should be cited as:
Department of Environment and Science, Queensland (2021) Land, WetlandInfo website, accessed 29 September 2021. Available at: https://wetlandinfo.des.qld.gov.au/wetlands/management/pressures/litter-illegal-dumping/sinks/land/