Rosin

 Rosin is an oleoresin derived from pine trees, primarily composed of C19H29COOH. It is categorized into three types: "gum rosin," "wood rosin," and "tall oil rosin." It is commonly used by the poultry slaughtering industry as a depilatory agent. While rosin itself has low toxicity to humans, it often contains heavy metals such as lead and other toxic compounds. Moreover, due to cost-saving practices in the industry, it is frequently reused, leading to oxidation that produces peroxides, which severely impact human health. As a result, it has become a regulated product.