👉 Leather fumes are a byproduct of the tanning process, which involves treating animal hides to make them durable and water-resistant. This process often releases volatile organic compounds (VOCs), including various aldehydes, ketones, and sulfur-containing compounds, which can permeate the air and create a distinctive, sometimes unpleasant odor. These fumes can be strong and lingering, especially in poorly ventilated areas, and may include notes of musty earth, ammonia, or even a faint metallic scent. While some people find these odors irritating, others might not notice them, but they are generally considered a natural part of leather's transformation from raw hide to finished product.
