Wool's Effects on Carbon Dioxide and Formaldehyde

The website for Thermafleece, a wool-based building insulation manufacturer in Cumbria, states

In the UK alone, 36 million sheep produce around 70 million kg of wool, locking up nearly 140 million kg of CO2 from the atmosphere.  That's the equivalent to the CO2 emissions from nearly 35,000 family cars....The complex protein structure of the wool fibre enables it to absorb and safely fix many airborne substances that can be harmful in the indoor environment, including formaldehyde, which is released from many fabricated materials in the home.

http://www.thermafleece.com/wonders-wool

The site features photographs of rugged sheep sporting naturally-coloured wool out on green rolling fields.