Final bag belt prototype.
Bag prototype held in place by the belt before attaching it to the stoma.
Algae-based material prototyping.
Prototyping manufacturing processed for open source production.
Testing belt & buckle designs.
What it does
os*tomy provides ecologically and economically sustainable stoma care for patients that currently cannot afford commercial colostomy products, and ostomy organizations who can manufacture safe supplies on a local scale with very little equipment.
Working at a Tanzanian hospital in August 2022 as a medical assistant gave hands-on insights into medical care and the handling of equipment in a country with no public health insurance and a very low average income. This meant a whole different urgency when starting a university project on ostomy care in October 2022. We could get in touch with patients, medical professionals as well as an African stoma organization, leading to practical in-depth insights. Recognizing the issues patients have in their daily life, their great dependency on donations, as well as the impact current practices have on the environment meant a clear call to action.
How it works
A colostoma is an artificial outlet for bodily waste, given to patients with severe bowel diseases, where the stool (output) is usually collected by a plastic adhesive bag. os*tomy’s core is a bag, made from 2 main ingredients: Agar agar, which is red algae-based and therefore widely available along coastlines without using arable land, and glycerol, plant oil based and a by-product of industries like soap production. Mixed with water, they form an easy-to-reproduce recipe that requires only simple tools like a heater, moulds and a hot stamp to cook, cast, and weld the foil pieces into a usable bag that is watertight, yet naturally biodegradable.The bag is held in place with a fabric belt, that has a reinforcing ring around the stoma opening and an adjustable auto-locking buckle. Using cloth also pays respect to textiles as centuries-old cultural assets. Keeping it simple enables stoma organizations to produce supplies on a local scale with regional resources.
A number of studies showed clear evidence, that the lack of medical supplies leads to misuse of waste bags or diapers on stomas. This means more trouble for patients and piles of non-recyclable, hard-to-dispose waste – especially in regions without publicly ran waste collection systems. Supported by real-world insights, the idea of providing organizations with a process for self-production from local resources was born. Investigating algae-based polymer recipes, many variants with shredded seaweed, sodium alginate and agar agar were tested until prototypes containing glycerol produced a first foil-like outcome. The mixture and cooking processes were refined and cast into moulds that got adjusted sizing according to the measured shrinkage of the material. The meltability was first tested with a soldering iron and eventually performed with a hot steel mug to proof weldability to a degree where a watertight bag could be produced. For the belt, fabric mockups led to a result which is both adjustable and stable. The sturdiness of the bag-belt-combination was tested in personal experiments, proving that the bag would stay in place when reinforcement elements on both components were added. Throughout the process, tools were kept very basic to ensure broad availability.
How it is different
With costs of 8–12€/ bag and a demand of at least two bags a day, colostomy patients face incredibly high costs for medical supplies they might need for the rest of their lives. Hence, many patients in countries without public health insurance are greatly dependent on ostomy organizations to distribute bags they receive as donations, making them, again, dependent on the will of suppliers or aid funds. Thus, a local, easy-to-setup production would make for a system that is also economically sustainable. For many ostomates today, the cheapest way out are old plastic bags, stuck to their belly using tape or a piece of cloth, which is likely to cause severe skin irritations or bleedings they have to live with on a daily basis. Yet, neither plastic bags, nor the great majority of professional stoma bags are naturally compostable in any way, whereas the os*tomy algae polymer is scientifically proved to degrade over a few months while being watertight when in use.
Further material testing is needed, to ensure skin compatibility and a safe test with ostomy patients. Along further testing, the belt should be optimized for patient fit and material efficiency. A first set of open source production tools should be put together with affordability and accessibility in mind, while aiming for process stability in the tests. Finally, reliable local sources for raw materials need to be found, which could even lead to public initiates for growing red algae. Surely, all next steps would highly benefit from the help of material and process specialists, and a close collaboration with established local organizations.