Biodegradable Bamboo Charcoal Toothbrush made from the world's fastest-growing plant: Bamboo. Our medium - soft charcoal bristle toothbrushes are BPA Free and infused with activated charcoal to double the teeth whitening effect. ** Bamboo is growing up to 98 inches in just 24 hours. This amazing plant does not require petrochemicals or artificial pesticides, making it both cost-effective and toxin-free.