Most people want to know how Bioska works from an environmental perspective, or in the sorting and treatment of biowaste.


Does Bioska
leave microplastics?

No. All Bioska products meet the European standard for industrial compostability EN 13432. The Finnish Environment Institute (SYKE) studied the decomposition of Bioska’s newest materials in both laboratory and marine conditions. The test showed that our material breaks down 100% into carbon dioxide, water and humus – even in natural conditions.


What materials are Bioska bags made from?
Bioska bags made from?

Bioska is a Finnish material innovation. We’ve been developing it in Ylöjärvi for over twenty years.

Our mission is to create products that are as durable as traditional plastic, but are also 100% compostable. The exact recipe is a secret, but 30–50% of our raw material is renewable vegetable starch. Bioska products are either plant-based or use polymers that are naturally produced by bacteria. In 2021, the EU will be banning a whole host of single-use plastics and the only acceptable replacements will be products made from natural polymers.


How durable are Bioska bags?

In autumn 2019, we commissioned a consumer survey in which more than a thousand randomly selected respondents held Bioska to be the most durable compostable biowaste bag on the market.

From time to time, we get feedback saying that a bag has ‘leaked’. The impression that the bag has leaked is caused by condensation that forms between the warm biowaste and the cooler sides of the container. Our newest product, Bioska Plus, solves even this problem. When a biowaste bag can breathe, no condensation forms and the bottom of the bag will be dry when it’s lifted out of the container. That is, if the material retains the biowaste’s moisture, like Bioska Plus does.


Do Bioska bags decompose
at waste treatment facilities

Bioska meets the European standard for industrial compostability EN 13432. Accordingly, 90% of the material is converted into carbon dioxide, water and humus within 180 days in industrial conditions. If the waste treatment facility’s process is shorter than this, it will usually remove the bags for incineration before composting the biowaste.

We’re continually developing our materials in collaboration with waste treatment facilities. Bioska Plus is currently our most easily tearable and fastest degrading product. It’s the only biowaste bag on the market that Stormossen (a waste treatment facility in Vaasa) recommends to customers alongside paper bags.


What does ‘industrially compostable’ mean?

Industrial compostability is specified by the European standard EN 13432. In order for packaging to be called compostable and biodegradable, one of the main criteria is that no more than ten per cent of the material should remain in a 2 mm sieve after 12 weeks of treatment. The processing temperature may vary between 40–70°C.

After six months of treatment at 58°C (+/- 2°C), at least 90% of the material must have decomposed into carbon dioxide, water and humus.

In addition to its decomposition, the material is also tested for any negative impacts on the composting process and the compost produced. Their absence is verified by numerous standardised measurements performed by an independent organisation. Therefore, it is also known that products with EN 13432 certification will only contain low concentrations of heavy metals.