Hi Reader, many conversations about lab sustainability stop at "we should use less plastic."
They rarely get to the point where someone actually tests whether reused plastic still gives you the same numbers at the bench.
However, I am here to get you those numbers.
So, let’s look at what is possible - specifically, through a paper that was published a few weeks ago:
Today's Lesson: Is Reusing Really Safe?
Assessing quality after multiple cleaning cycles
Number of the Day
Labcon has shown that their tubes can be reused at least five times, even if you freeze them at -40 °C for 3 hours, wash them with an overnight soak, or autoclave them for 15 minutes at 121 °C after each cycle. This data is remarkable because it comes from the manufacturer itself. Labcon is supporting reuse with its own name, despite the natural incentive for companies to sell more products. However, there is also a lot of interesting academic data on this topic too that we should explore:
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Reusing Laboratory Items
A few months ago, I was in touch with Phoenix Impact - a start-up that enables labs to reuse their plastic items.
They collect consumables from BSL-1 laboratories, recondition them, and ship them back ready to use.
Phoenix picks it up, runs a decontamination step, then an acid and an alkaline wash using their own solutions, followed by several rinses.
Thereafter, the items are dried, sorted, and packaged. At an external facility, they are sterilized with ethylene oxide (EtO) before being returned to the lab.
But do all these steps degrade the quality of your lab items?
They now published a case study - Mansouri et al. share the following data:
Settling Quality Concerns
Many labs that intend to reuse items wash, soak, or autoclave them.
Phoenix Impact worked together with different facilities in Montreal to obtain their items and then subjected them to five treatment cycles:
Cuvettes
For instance, they tested reconditioned polystyrene cuvettes with potassium dichromate solutions and Eosin Y.
They found no significant differences compared with new cuvettes, either in the blanks or in the filled cuvettes.
Absorbance for 20 mg/L and 120 mg/L potassium dichromate (PD) solutions was measured at 350 nm, while absorbance for the 600 mg/L PD solution was measured at 430 nm and that for the Eosin Y solution at 517 nm, using new and reconditioned cuvettes.
Pipette Tips
Similarly, they tested 30 tips for each of four pipette volumes.
Both new and reconditioned tips stayed within the manufacturer's acceptance criteria for accuracy and coefficient of variation under every condition.
BCA Assay
Using 96-well plates and 1.5 mL tubes, standard curves remained linear and were almost indistinguishable from each other.
There are a few points worth noting regarding these graphs. First, the increase in standard deviation is expected as the absorbance values increase. Regarding the absorbance of water, which was measured to verify that there was no plastic degradation or leaching, as well as no residual contents - more noticeable variations can be observed for Plate 2. The cause of these variations is unclear. If I had to speculate, they are most likely attributable to a manufacturing-related effect specific to this lot, since leachates or residual chemicals would be more likely to result in increased absorbance.
In other words, for protein quantification assay standards, they found no significant differences in absorbance.
Cell Culture
Some cell and tissue culture items are surface-treated, raising concerns about whether acid, alkaline solutions, or EtO would affect that treatment.
They tested Rat-1 fibroblasts on 6-well TC-treated plates reused up to five times.
They observed 81–98% viability compared with 93% in new plates, and 83–93% confluency compared with 87%. Mean cell area and aspect ratio were also within normal ranges.
Click to enlarge. n = 4 for cell viability and confluency, while n = 10 for individual cell area. Microscopy images were acquired at 40× magnification. Personally, I would not have chosen bar graphs in this instance; a box plot or a plot showing the mean with SD or 95% confidence intervals would be more informative for assessing variability in the data. Here is the full figure if you would like to zoom in and examine the individual data points.
However, there is one important caveat: they did not perform sterility testing or endotoxin quantification.
Functional equivalence in these assays is not the same as microbiological equivalence, and the authors say so themselves.
More Data for You
Of course, these data were generated together with the founders of the company. However, their findings are in line with what others have found:
Clancy et al. showed that used Xenopus culture dishes rinsed and soaked for 10 min in 70% ethanol maintained full embryo survival.
Veyssi et al. showed that detergent-washed, sonicated, and UV-C-treated pipette tips carried no infectious phage and no nucleic acid above NanoDrop's detection floor, and titrated identically to fresh tips.
Trusler et al. investigated the reuse of glass pipettes and bottles cleaned with Virkon (a disinfectant) and dry-baked at 180 °C for 2 h for use in cell culture. The result: seven passages of antibiotic-free primary fibroblast culture with no change in growth, viability, or IL-6.
Applying the Knowledge
There is no doubt that reuse is possible; the real question is where in your own workflow it makes sense.
If in doubt, first ask yourself what evidence you need before you can trust reused items in that application.
Reuse has also been explored in bacterial work. Bryant Jr. et al. introduced TidyTron, a library of protocols for the automated cleaning of micropipette tips and microtiter plates. Regarding these figures, the authors state: “E. coli expressing four unique chromoproteins was plated with a decontaminated tip. Each arrow signifies a tip cleaning and the order in which plates were prepared. […] B) E. coli and LB plating experiment was performed in triplicate along with E. coli plates prepared using fresh tips.”
Moreover, reuse does not necessarily mean going through excessive wash cycles.
I reused dishes for neuronal cultures during routine passaging and immediately reused tips for similar solvents.
In terms of environmental impact, the savings are obvious if you reuse items directly or simply rinse them. Even when you autoclave or wash them, it still seems that the savings are fairly substantial.
All in all, in the case study from Phoenix Impact, the participating labs generated ≈500 kg of plastic over an average of 5 months.
Now imagine you could cut that in half by reusing each item once - the plastic you would save would weigh more than you could lift!
How We Feel Today
References
Mansouri, N.S., et al., 2026. Environmental impact and experimental reliability of reusing plastic consumables in wet labs. npj Materials Sustainability, 4, p.21. doi:10.1038/s44296-026-00108-9.
Clancy, M., et al., 2023. Facile methods for reusing laboratory plastic in developmental biology experiments. Differentiation, 130, pp.1–6. doi:10.1016/j.diff.2022.11.001.
Veyssi, A., et al., 2025. Bio-contaminated plastic micropipette tip sterilization stations: Environmentally, economically, and energetically viable solution. Waste Management, 196, pp.71–79. doi:10.1016/j.wasman.2025.02.004.
Trusler, E.C., et al., 2024. Reusable glassware for routine cell culture—a sterile, sustainable and affordable alternative to single-use plastics. Frontiers in Sustainability, 5, p.1447236. doi:10.3389/frsus.2024.1447236.
Bryant, J.A. Jr., et al., 2024. TidyTron: Reducing lab waste using validated wash-and-reuse protocols for common plasticware in Opentrons OT-2 lab robots. SLAS Technology, 29(2), p.100107. doi:10.1016/j.slast.2023.08.007.
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