Evidence of human pollution has finally reached the most remote wilderness on Earth as polymer fragements have been discovered in Antarctic sea ice.
Scientists found microplastics in an ice core taken from the frozen continent and believe it is the first such evidence of its kind.
However, similar microplastic pollution has been found previously in Antarctic surface waters, sediment and in snow.
The plastic was surrounded by algae and the scientists believe krill in the region, which feast on sea ice, could be eating plastic particles.
This, they say, could have potentially enormous ramifications if plastic pollution is indeed infiltrating the food chain at the very bottom.
Scientists at th University of Tasmania found microplastics in an ice core taken from the frozen continent and believe it is the first such evidence of its kind. The core contained 96 microplastic fragments in total
Fourteen different types of plastic were found in the sample and a dozen individual pieces of plastic were found per litre.
The most commonly found polymer was polyethylene (PE), which includes LDPE and HDPE fragments, used to make all manner of goods from bottles to window frames.
These account for more than a third (34 per cent) of all fragments found.
The next most commonly found polymers were polypropylene (PP) and polyamide (PA) which includes nylon, accounting for 15 and 14 per cent, respectively.
The 3.4ft long ice core was first extracted in 2009 and stored at the University of Tasmania.
A total of 96 particles were discovered which fit the criteria of being a ‘microplastic’, — measuring 5mm or shorter.
Anna Kelly from the Institute for Marine and Antarctic Studies at the University of Tasmania, who led the study, told The Guardian: ‘The remoteness of the Southern Ocean has not been enough to protect it from plastic pollution, which is now pervasive across the world’s oceans.’
The find comes after it was reported last year that tiny pieces of plastic were found in ice cores drilled in the Arctic.
This piece of research by US-based researchers on ice floes during an 18-day icebreaker expedition through the Northwest Passage unearthed evidence of plastic.
However, the pieces of plastic found by the Australian team in Antarctica were larger than the fragments seen in the north.
According to the researchers, this is likely a result of a local source of pollution.
Microplastics enter the waterways through a variety of means and finish suspended in the liquid. They can be transported long distances both in water and via the air, taking them to the furthest corners of the world
Pictured, the biggest producers of plastic worldwide, as well as predicted growth for the future, based on the latest available data from 2013
Associate Professor Delphine Lannuzel was part of the study which drilled the ice core more than ten years ago, two kilometers from the Antarctic coast.
Analysis revealed the ice was surrounded by algae, indicating it was being ingested by some lifeforms.
‘Sea ice is habitat for key foraging species,’ Dr Lannuzel said. ‘Krill defines everything else in the food chain and it relies on sea ice algae to grow.
‘When you think now that sea ice algae is associated to plastics, you can think about the bioaccumulation of the plastics in krill and in whales.’
Earlier this month, a poiece of research emerged from the American Chemical Society which found lobsters can eat and break down some microplastics.
This then releases even smaller fragments into the water that other deep-sea organisms could ingest.
This proves the existence of a ‘secondary’ chain of events pertaining to microplastics that causes a severe knock-on effect and could see all animals, large or small, impacted by the human scourge.
WHAT FURTHER RESEARCH IS NEEDED TO ASSESS THE SPREAD AND IMPACT OF MICROPLASTICS?
The World Health Organisation’s 2019 report ‘Microplastics in Drinking Water’ outlined numerous areas for future research that could shed light on how far spread the problem of microplastic pollution is, how it may impact human health and what can be done to stop these particles from entering our water supplies.
How widespread are microplastics?
The following research would clarify the occurrence of microplastics in drinking-water and freshwater sources:
- More data are needed on the occurrence of microplastics in drinking-water to assess human exposure from drinking-water adequately.
- Studies on occurrence of microplastics must use quality-assured methods to determine numbers, shapes, sizes, and composition of the particles found. They should identify whether the microplastics are coming from the freshwater environment or from the abstraction, treatment, distribution or bottling of drinking-water. Initially, this research should focus on drinking-water thought to be most at risk of particulate contamination.
- Drinking-water studies would be usefully supplemented by better data on fresh water that enable the freshwater inputs to be quantified and the major sources identified. This may require the development of reliable methods to track origins and identify sources.
- A set of standard methods is needed for sampling and analysing microplastics in drinking-water and fresh water.
- There is a significant knowledge gap in the understanding of nanoplastics in the aquatic environment. A first step to address this gap is to develop standard methods for sampling and analysing nanoplastics.
What are the health implications of microplastics?
Although water treatment can be effective in removing particles, there is limited data specific to microplastics. To support human health risk assessment and management options, the following data gaps related to water treatment need to be addressed:
- More research is needed to understand the fate of microplastics across different wastewater and drinking-water treatment processes (such as clarification processes and oxidation) under different operational circumstances, including optimal and sub-optimal operation and the influence of particle size, shape and chemical composition on removal efficacy.
- There is a need to better understand particle composition pre- and post-water treatment, including in distribution systems. The role of microplastic breakdown and abrasion in water treatment systems, as well as the microplastic contribution from the processes themselves should be considered.
- More knowledge is needed to understand the presence and removal of nanoplastic particles in water and wastewater treatment processes once standard methods for nanoplastics are available.
- There is a need to better understand the relationships between turbidity (and particle counts) and microplastic concentrations throughout the treatment processes.
- Research is needed to understand the significance of the potential return of microplastics to the environment from sludge and other treatment waste streams.
To better understand microplastic-associated biofilms and their significance, the following research could be carried out:
- Further studies could be conducted on the factors that influence the composition and potential specificity of microplastic-associated biofilms.
- Studies could also consider the factors influencing biofilm formation on plastic surfaces, including microplastics, and how these factors vary for different plastic materials, and what organisms more commonly bind to plastic surfaces in freshwater systems.
- Research could be carried out to better understand the capacity of microplastics to transport pathogenic bacteria longer distances downstream, the rate of degradation in freshwater systems and the relative abundance and transport capacity of microplastics compared with other particles.
- Research could consider the risk of horizontal transfer of antimicrobial resistance genes in plastisphere microorganisms compared to other biofilms, such as those found in WWTPs.
Can water treatment stop microplastics entering our water supplies?
Although water treatment can be effective in removing particles, there is limited data specific to microplastics. To support human health risk assessment and management options, the following data gaps related to water treatment need to be addressed:
- More research is needed to understand the fate of microplastics across different wastewater and drinking-water treatment processes (such as clarification processes and oxidation) under different operational circumstances, including optimal and sub-optimal operation and the influence of particle size, shape and chemical composition on removal efficacy.
- There is a need to better understand particle composition pre- and post-water treatment, including in distribution systems. The role of microplastic breakdown and abrasion in water treatment systems, as well as the microplastic contribution from the processes themselves should be considered.
- More knowledge is needed to understand the presence and removal of nanoplastic particles in water and wastewater treatment processes once standard methods for nanoplastics are available.
- There is a need to better understand the relationships between turbidity (and particle counts) and microplastic concentrations throughout the treatment processes.
- Research is needed to understand the significance of the potential return of microplastics to the environment from sludge and other treatment waste streams.
Share or comment on this article:
