Chemicals and other water treatments are potentially harmful to humans, plants and animals. Barley straw is completely safe for the humans who handle it and the animals and plant life that consume water treated with Stock Tank Secret: The barley straw used in Stock Tank Secret is 100% organic, grown by a certified organic farmer. No chemicals, pesticides or herbicides are used in the raw materials or the manufacturing process used to make Stock Tank Secret. As Stock Tank Secret works to treat your tank, there are no toxic effects, as the process is completely natural. The burlap bags is completely biodegradable and won’t harm the environment.