Organic cotton helps farmers escape the health risks and financial burden of toxic chemicals involved in conventional cotton production. It also helps wider communities by maintaining (rather than draining) the local water supply and keeping it clean.

Blending polyester with cotton can add strength and durability to the fabric. Using recycled fibres reduces the fossil fuel-based inputs needed to manufacture polyester. Whilst also helping to divert old garments from landfills. (Patagonia Common Threads) But some may prefer to avoid synthetic fibres in products where fully natural alternatives are available. 

As a plant-based fibre, rayon viscose - which this hoodie is embroidered with - is not inherently toxic or polluting. However the process required to turn the woody fibres into a usable fine thread is chemically intensive and can be a highly polluting process. (Good On You)