Kindly Note: Wood is a natural product and blackens when exposed to moisture. This is not considered a fault. To avoid this do not leave your brush submerged in water for long periods. Best to keep dry and if needed hand wash with warm soapy water and dry thoroughly after washing. Not dishwasher safe. Arenga is a very special material and a safe natural fibre, after several uses individual bristles may come loose and fall out, this is normal, you can brush them away to remove from your cooking area.