cotton, also known as vegetable wool, is a major source of apparel fiber. celebrated for its excellent absorbency, durability, and intrinsic softness, cotton accounts for over 50% of all clothing produced worldwide. this makes cotton the most widely used clothing fiber. cotton is one of the most chemical-intensive crops in the world. conventionally grown cotton uses approximately 25% of the world's insecticides and more than 10% of the world's pesticides. however, growing and processing this particular fiber crop is largely unsustainable. for every pound of cotton harvested, a farmer uses up 1/3 lb of chemical, synthetic fertilizer. as a whole, the us cotton production makes up 25% of all pesticides deployed in the united states. worldwide, cotton takes up 2.4% of all arable lands yet requires 16% of the world's pesticides. furthermore, the cotton hulls contain the most potent insecticide residues. they are often used as cattle feed, which means that consumers are purchasing meat containing a concentration of pesticides. the processing of cotton into usable fibers also adds to the burden on the environment. manufacturers prefer cotton to be white so that cotton can easily be synthetically dyed to any shade of color. natural cotton is actual beige brown, and so during processing, manufacturers would add bleach and various other chemicals and heavy metal dyes to make cotton pure white. formaldehyde resins would be added in as well to form "easy care" cotton fabric.