{"id":310,"date":"2022-01-28T06:19:12","date_gmt":"2022-01-28T06:19:12","guid":{"rendered":"http:\/\/wp.lancs.ac.uk\/lec101blog\/?p=310"},"modified":"2022-01-28T06:19:30","modified_gmt":"2022-01-28T06:19:30","slug":"310","status":"publish","type":"post","link":"http:\/\/wp.lancs.ac.uk\/lec101blog\/2022\/01\/28\/310\/","title":{"rendered":"Microplastics: are they a micro problem? Investigating how to effectively mitigate microplastic pollution"},"content":{"rendered":"

By Alisa Reid<\/em> –\u00a0<\/span><\/p>\n

Plastic pollution is a critical long-term problem with ~400Mt produced annually [1]. Microplastics are an important contributor; classified as <5mm in diameter. There are two classes; primary (manufactured at size) or secondary (eroded to classification size) [2]. This pollution is challenging to successfully mitigate as their size often enables them to enter natural environments unnoticed. The durability of plastic indicates microplastic pollution will be a lasting problem, with the additional danger of unknown health risks. By preventing the flow of microplastics into marine environments it may be possible to mitigate microplastic pollution in oceans. One method involves using wastewater treatment technologies (WWTPs). The Talvitie (2017) study [3] verifies that advanced final-stage WWTPs significantly reduce the number of microplastics discharged into marine environments, but is filtration of this type a viable solution to microplastic pollution?<\/span><\/p>\n

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Labelled microplastics from the San Francisco Bay area. Image: Cole Brookso<\/p><\/div>\n

Problems<\/strong><\/span><\/p>\n

Being small increases the likelihood of microplastics being ingested by organisms. Studies on terrestrial environments have revealed microplastics can reduce soil viability [4]. This has the potential to affect food production and security, emphasising how pressing an issue microplastic pollution is.<\/span><\/p>\n

Moreover, microplastics can become coated in toxic chemicals, heavy metals, and persistent organic pollutants [3]. Research into whether there are adverse human health effects from ingestion of microplastics (through contamination of food) is ongoing. Some concerns are based around the possibility of biomagnification of these harmful substances [1].<\/span><\/p>\n

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Cleaning microplastics (known as nurdles) from Arniston beach in Western Cape, South Africa. Image: Tom Camacho\/Science Photo Library<\/p><\/div>\n

Solutions<\/strong><\/span><\/p>\n

Many technologies which filter microplastics from effluents are available, but with varying efficacy. The Talvitie (2017) study compares several types, including a membrane bioreactor (MBR), which it concludes is the most effective: 99.9% removal rate of microplastics. No other technology achieved this percentage of microplastic removal:<\/span><\/p>\n