Conventional cotton is grown with GMO seeds and uses 16% of pesticides globally. It's a water-intensive crop due to irrigation and an average T-shirt takes 713 gallons of water (!!) to make. Organic cotton uses 91% less water and is grown from GMO free seed.

This cheap, synthetic fiber is made from polyacylonitrile, a soft plastic and known carcinogen in a chemical- and energy-intensive process. Waste water and toxic products are difficult to treat and acrylic fiber is non-recyclable when the garment wears out.

The growing and feeding of silk worms requires massive amounts of trees and growth hormones. Harmful de-gumming chemicals are also used to extract silk threads from the worms.

Viscose and Rayon products usually start with unknown tree sources and use toxic chemicals to strip the "natural" fibers. Emissions from viscose production heavily pollute water and air with things like nitrates, phosphates and iron. All by-products are non-reusable.

Bamboo may be a water-friendly, fast-growing plant, but processing stalky bamboo into silky textiles requires some heavy-duty chemicals and energy in a viscose production. There are also many issues with unregulated tree-sourcing and deforestation in ancient bamboo forests.