The Plastic in Your Body, and Why We Use Bioplastics

The Study: Seven Days, Measurable Change

In April 2026, researchers at the University of Western Australia published the PERTH Trial (Plastic Exposure Reduction Transforms Health) in Nature Medicine — one of the most respected medical journals in the world. It's the kind of rigorous, peer-reviewed work that's rare in this space.

The team followed a cohort of 211 Australians, then ran a randomised controlled trial with 60 participants. For seven days, the intervention groups ate food that minimised plastic contact from paddock to plate, cooked with plastic-free kitchenware, and used personal-care products low in plastic chemicals. The control group changed nothing.

Then they measured the plastic-associated chemicals in participants' urine. The results were striking.

That's the genuinely encouraging part. These chemicals didn't take months to clear — a week was enough. The body was carrying them largely because it was being continuously topped up from packaging, utensils, and the everyday plastic that touches what we eat. Reduce the source, and levels fall quickly.

Why These Chemicals Matter

BPA and phthalates belong to a class of compounds called endocrine-disrupting chemicals. That's a clinical way of saying they interfere with your hormones — the signalling system that regulates growth, metabolism, and reproduction.

The research linking them to health outcomes has been building for two decades. The PERTH researchers point to associations with infertility and cardiometabolic disease, and their own cohort found relationships between these chemicals and cardiometabolic biomarkers. This is an active field rather than a closed one, but the evidence has been pointing in a consistent enough direction, for long enough, to be worth taking seriously.

The other thing worth understanding is that these compounds aren't locked into the plastic. They migrate out of it gradually, and they do so a little faster in warmth and in contact with moisture. That's true of the container in your fridge and it's equally true of plastic anywhere else.

What This Has to Do With Grow Gear

The starting point is worth stating plainly: a grow room is full of plastic. Pots, trays, drain lines, hoses, pump housings, impellers, reservoir fittings, sensor enclosures. It's the material the entire industry is built from, and nobody — hobbyist or commercial — is going to swap all of it out.

We're also not going to suggest that growers are worse off than anyone else. Plastic is simply everywhere in modern life. The PERTH participants cut their exposure by changing food packaging, kitchenware and personal-care products, not grow equipment. This isn't a horticulture problem, and if you grow indoors you haven't done anything to be concerned about.

What does seem fair to say is that it accumulates in both directions. Every piece of conventional plastic that gets replaced with something better is a small reduction — for you, and for anyone who eats what you grow. You won't get to zero, and you don't need to. It's a long game, and the choices that are easy to make are worth making.

Why We Build From Bioplastic

We can't do much about your pots or your pump impellers. What we can control is what our own hardware is made from, so that's where we started. Every OMGrow enclosure and housing is 3D printed from polylactic acid (PLA) — a bioplastic made from renewable plant starch rather than petrochemicals.

The critical difference isn't just that it's plant-based. It's what PLA doesn't contain. There's no BPA, because PLA isn't a polycarbonate. It doesn't need phthalate plasticisers to hold its shape. The endocrine-disrupting compounds the PERTH Trial measured simply aren't part of the material.

• ✓ No bisphenols — PLA contains no BPA or BPS
• ✓ No plasticisers at all — not phthalates, and not the polyethylene glycol or citrate esters that some PLA compounds use
• ✓ Renewable feedstock — made from plant starch, not crude oil
• ✓ Nothing measurable coming out — migration testing on printed samples found no detectable migration in any food simulant

What's Actually In Our Filament

"PLA" on its own doesn't tell you much. It's a category, not a recipe, and a filament sold as PLA can legitimately contain plasticisers and processing additives that never appear on the label. So the material matters less than the specific product, and the specific product needs documentation behind it.

We print in Bambu Lab PLA Pure, which publishes its full formulation — an unusual thing for a filament maker to do. Five ingredients: polylactic acid, an acrylate copolymer as an impact modifier, colorants, ethylene bis stearamide as a lubricant, and asbestos-free talc as a nucleating agent. The important part of that list is what isn't on it. There is no plasticiser of any kind, because PLA is rigid enough without one.

The formulation is the claim; the testing is the proof. Independent SGS analysis under EU Regulation 10/2011 measured overall migration in all four required food simulants and found none detectable in any of them, against a limit of 10 mg/dm². That includes the acidic aqueous simulant — 3% acetic acid held at 70°C for two hours, which is hotter and harsher than anything a sensor housing will ever encounter. Separate testing to EN 71-3 Category III, which simulates stomach acid on scraped material, found no detectable soluble organic tin, addressing the residual polymerisation catalyst that's the one genuine question mark in PLA chemistry.

Two limits on that. The testing was performed on printed samples of the filament, so it speaks to the material we build from rather than certifying any particular finished part of ours — and we're not claiming our enclosures are food-safe, because printed parts have layer lines and layer lines are a hygiene problem no chemistry can fix. What the reports do establish is the narrow thing we actually care about: under conditions harsher than a grow room, nothing measurable came out of a printed part.

Why 3D Printing Makes This Possible

There's a reason most grow equipment isn't made from bioplastic, and it isn't that manufacturers haven't thought of it. It's tooling.

Injection moulding runs on steel moulds, and a mould is only worth cutting if it's going to run a very long time. Once a design is committed to that process, the material decision becomes an economic one: whichever resin flows well, cycles fast, and costs least per tonne. That's how ABS, polycarbonate and PVC became the industry default — they're inexpensive in bulk and they mould well, and once the tooling exists the material is locked in for its life.

Printing takes that constraint off the table entirely. With no mould dictating the decision, the material becomes an open choice rather than a financial one, and we can specify PLA for the simple reason that it's the right material for gear that lives in a warm, humid room next to your plants.

The Limits of PLA

PLA has real limitations, and they're worth knowing before you decide it's the answer to everything. Like any solid material, it can eventually break down into microplastic particles.

It would be convenient if PLA microplastics were the gentler option, but the research doesn't support it. Studies comparing bioplastic and conventional microplastics in soil have found PLA can be as disruptive as PET or more so — in one 28-day trial, PET microplastics caused no measurable effect on earthworms while PLA measurably shifted their oxidative status. The field is young and the evidence isn't settled, but there's currently no basis for claiming a microplastic advantage.

The defensible claim is narrower, and more useful. It's about what comes out of an intact part across years of service in a warm, humid room. PLA has no bisphenols to leach and needs no phthalate plasticisers, because neither is part of the chemistry. That's the exposure the PERTH Trial was measuring, and it's the one we've designed out.

It also won't compost in your green bin. PLA needs sustained industrial heat to break down, and almost no Australian council will accept it.

The Bigger Picture

One blog post isn't going to change the industry overnight. But it's worth saying plainly: the material something is made from matters, and the manufacturing industry's default is not the only option available.

If reading this makes you look a little harder at the plastic around your food and your grow, that's a win, whether or not you ever buy anything from us. The PERTH Trial showed how readily the body responds when the source is reduced. Choosing better materials where it's easy to do so is how that starts.