Spectrometry Reveals Extent of Microbial Growth in Lakes Caused by Plastic

A recent paper published in Nature Communications reveals that plastic leachate is more chemically different, bioavailable, and promotes more microbial growth in water than natural organic matter.

Study: Plastic Pollution Fosters More Microbial Growth in Lakes than Natural Organic Matter. Image Credit: Rich Carey/Shutterstock.com

Freshwater is heavily polluted by plastic. Plastic breakdown, both abiotic and biotic, releases carbon-based substrates for heterotrophic development. However, there is limited understanding of how these novel chemical compounds affect microbial metabolism.

This study reveals that plastic pollution may promote aquatic food webs and identifies areas where pollution reduction techniques may be most successful.

Significance of Plastic in Growth of Bacteria

Microbes' responses to widespread and increasing plastic contamination in freshwaters affect ecosystem metabolism and food web health. Plastics leach dissolved organic matter (DOM) through photochemical, mechanical, and biological deterioration, providing a foundation for biofilm colonization.

This plastic leachate may supply energy for bacterial development and can be transmitted upwards via food webs to enable higher trophic level growth. However, harmful chemicals added to synthetic polymers during manufacturing to promote plastic flexibility and heat stability may inhibit microbial growth in plastic leachate.

As many of these harmful additions are hydrophobic organic chemicals that bind securely to synthetic polymers, they can damage and biomagnify higher trophic levels that consume bacterial decomposers.

Determining the optimal circumstances for bacteria to proliferate and deplete plastic leachate from the environment might assist in prioritizing efforts to reduce and clean up global plastic pollution.

Relationship Between DOM and Bacteria

Bacteria's ability to break down plastic leachate is affected by the molecular composition of natural DOM, which varies across lakes and rivers.

The molecular composition of natural dissolved organic matter varies between lakes and rivers, influencing bacteria's ability to degrade plastic leachate.

In waters with labile DOM, leachate may not benefit bacteria because bacteria might not adapt to these substrates.

Their functional properties vary throughout space due to stochastic mechanisms, dispersal histories and environmental factors.

Investigating the Effects of Plastic Leachate on Microbial Growth in Lakes

Sheridan et al. proposed that the chemical composition of the preexisting lake's DOM influences the response of microorganisms to plastic leachate.

Surface waters from 29 lakes with varying concentrations of dissolved organic matter were incubated with and without low-density polyethylene (LDPE) plastic leachate.

The surface lake water was treated with an ecologically realistic quantity of leachate or an equivalent volume of distilled water.

The chemical composition of natural occurring DOM was compared to plastic leachate using Fourier-transform mass spectrometry.

The bacterium protein production (BPP) was determined by biomass uptake and growth efficiency (BGE).

Significant Findings of the Study

Plastic-derived DOM differed significantly from natural DOM in stimulating bacterial growth. Plastic leachate had more than doubled bacterial biomass production compared to the control treatment.

The molecular formulae of DOM from plastic leachate were less diverse. However, plastic leachate showed a greater lability index and included 35% unique molecular formulae.

Despite providing minimal carbon to the lake's DOM, plastic leachate boosted the BGE and BPP of natural bacterial populations after three days. Adding plastic leachate raised mean BPP by 2.29 times and BGE by 1.72 times.

Bacterial growth was more efficient in the presence of plastic leachate than when only natural lake DOM was available. The addition of plastic leachate increased BGE by 1.72 times compared to the control treatment.

The impact of plastic leachate on BGE varied with the variety of bacteria present in the lake. High amounts of plastic leachate can inhibit microbial growth because they include many harmful chemicals.

Plastic pollution can stimulate marine food webs and indicate locations where pollution mitigation techniques may be most effective.

Limitations of the Study

The research only examined bacteria. However, other microorganisms, such as fungus and microalgae, are similarly impacted by plastics and plastic leachates. These new interactions may affect how ecosystems respond to plastic waste.

The experiment only leached LDPE. The chemical composition of leachate from various plastics will undoubtedly vary. Therefore, the type of plastic in lakes may also affect microorganisms and the surrounding ecosystem differently.

The research employed a single LDPE concentration to represent plastic concentrations in lakes. Higher concentrations may have less beneficial effects on microorganisms due to harmful chemicals.

The Future of Plastic Pollution in Lakes

Plastics will continue to harm the ecosystem for a long time. Therefore, the results of this study are valuable as they indicate the lakes that would benefit most from plastic pollution control by removing dissolved plastic leachate.


Sheridan, E.A., Fonvielle, J.A., Cottingham, S., Zhang, Y., Dittmar, T., Aldridge, D.C., & Tanentzap, A.J. (2022). Plastic Pollution Fosters More Microbial Growth in Lakes than Natural Organic Matter. Nature Communications. 13, 4175. https://www.nature.com/articles/s41467-022-31691-9

Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of AZoM.com Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.

Owais Ali

Written by

Owais Ali

NEBOSH certified Mechanical Engineer with 3 years of experience as a technical writer and editor. Owais is interested in occupational health and safety, computer hardware, industrial and mobile robotics. During his academic career, Owais worked on several research projects regarding mobile robots, notably the Autonomous Fire Fighting Mobile Robot. The designed mobile robot could navigate, detect and extinguish fire autonomously. Arduino Uno was used as the microcontroller to control the flame sensors' input and output of the flame extinguisher. Apart from his professional life, Owais is an avid book reader and a huge computer technology enthusiast and likes to keep himself updated regarding developments in the computer industry.


Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Ali, Owais. (2023, May 13). Spectrometry Reveals Extent of Microbial Growth in Lakes Caused by Plastic. AZoOptics. Retrieved on April 20, 2024 from https://www.azooptics.com/News.aspx?newsID=27736.

  • MLA

    Ali, Owais. "Spectrometry Reveals Extent of Microbial Growth in Lakes Caused by Plastic". AZoOptics. 20 April 2024. <https://www.azooptics.com/News.aspx?newsID=27736>.

  • Chicago

    Ali, Owais. "Spectrometry Reveals Extent of Microbial Growth in Lakes Caused by Plastic". AZoOptics. https://www.azooptics.com/News.aspx?newsID=27736. (accessed April 20, 2024).

  • Harvard

    Ali, Owais. 2023. Spectrometry Reveals Extent of Microbial Growth in Lakes Caused by Plastic. AZoOptics, viewed 20 April 2024, https://www.azooptics.com/News.aspx?newsID=27736.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this news story?

Leave your feedback
Your comment type

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.