You may have noticed that in some videos the climbers’ hands are darkened. This is due to the rope accumulating dirt, but also aluminum from rubbing on carabiners and belay devices made of aluminum alloys.
Aluminum is the most abundant metal in the Earth’s crust, so we are naturally exposed to it through air, water, soils, and rocks. Aluminum and its alloys are also widely used in many industries and can be found in our food, cosmetics, and even medicines.
When aluminum comes into contact with air, it forms aluminum oxide. When ingested, about 99% is eliminated through feces and urine, but a small portion remains in the body. Aluminum is not useful to our body, and it is potentially dangerous. It is impossible to avoid all exposure, but it’s a good idea to limit how much we take in. If your hands get dirty at the crag, you can rinse them before eating your sandwich.
Most ropes can be cleaned. The manufacturer’s instructions for your specific rope should be followed. An improperly cleaned or dried rope can be damaged and weakened. If you can’t find specific information, call the manufacturer’s customer service.