Advice on Modelling Microplastics in LCA: Databases and Methodologies

Question

Hi all

I’m doing an LCA for a sweater that is primarily made of polyester fibers and want to address the environmental impacts of microplastics. My focus is on upstream production (fx losses to environment in pellet production) and the use phase (e.g. microplastic release during washing).

I’m finding it difficult to determine how, or if, microplastics are currently integrated into existing LCA databases or methodologies. Does anyone have advice or experience on how to model this? Are microplastic emissions already addressed in any databases?

I’ve come across GreenDelta’s “littering probabilities” approach (Elementary litter in life cycle inventories, Ciroth & Kouame, 2019). While I’m not entirely sure I understand all the details, I wonder if a similar probabilistic method exist and could be adapted for microplastics.

I realize this is a slightly vague request, but any advice, resources, or thoughts on this topic would be greatly appreciated!

Thank you in advance.

PS: I’m currently using Ecoinvent 3.9.1 as my database and ReCiPe 2016 as my impact assessment method.

Answer 1

Hi,

interesting question indeed. There is some movement in the microplastic assessment within LCA, the MarlLCA method and a method reported by Fraunhofer address it: Corella-Puertas et al. 2023, doi.org/10.1016/j.jclepro.2023.138197 and Maga et al. 2022, doi.org/10.1007/s11367-022-02040-1. However, LCA databases don't have information on the emission of microplastics yet.

Indeed, you can use the plastic littering extension (PLEX, https://nexus.openlca.org/database/PLEX) to assess the plastic littering risk. This is a reasonable approximation for the generation of littered plastic. But to come from here to the formation of micro/macroplastic is a bit tricky but with assumptions, I think it could be fine. Also have a look at the PLEX methodology to also model your foreground model accordingly: https://nexus.openlca.org/ws/files/29729 and https://nexus.openlca.org/ws/files/35714.

We will publish in a few months reports from our research findings within the PRIMUS project addressing such issues.

Hope this helps

Comments

Thank you for your quick response Jonas. Glad to know it is a developing area - hopefully it will become more integrated soon. PLEX and MariLCA looks very relevant, will give both that and the publications a look, thank you for pointing me to that!
Look forward to your findings from the PRIMUS project. Didn't know that was ongoing, but sounds interesting.

Answer 2

Hi! I'm not sure if this is much help, but check out Marine Impacts in LCA and their characterization of Microplastics. They've published a few papers on this too, where you can get additional info.

Characterization Factors for Microplastics Impacts in LCA | MariLCA

It looks as though you will have to use the Impact World + methodology with these CFs. 

Hope this helps!

Answer 3

Hi there,

I did some research on that some time ago, so here is what I know.

There is an entire project on MPs in LCA (https://marilca.org/) who are doing great work.
They have developed characterisation factors by now, which should be implemented in ImpactWorld for openLCA although I haven't tried yet.

As far as I understand it, you have to know the amount, type and shape of your MPs and then you can calculate the impact in a new category.

I performed calculations in openLCA, also using ecoinvent and added the MPs later on in Excel. Please let me know if you need further information.