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I have used natural fiber rupees, hemp and jute, for a number of years for yoga type activities where repeated handling of the rope is common. What I have always understood is that "industrial" rope, such as that you would get from hardware stores and the like, is manufactured using some chemicals that are not healthy over time. Of course, buying the rope from other "organic" sources negates the issue. Even with organic rope, I wash it: mild detergent, loosely coiled in a tied pillowcase on a gentle cycle. After I will hang it loosely over a a clothesline as to avoid kinks in the rope and give it a few days to fully dry. I typically finish by running it through my hands with a few drops of baby oil. The first time I do this, there are often rope "splinters" bits. I will usually quick run my propane torch over the length to reduce those bits. Hope this helps.