Polypropylene fibers continue to contaminate wool

Preparation of a clean wool clip is important to the lamb industry. According to several industry experts, the contamination by polypropylene fibers is a serious problem. The following information was taken from the American Sheep Industry Association website at Sheep USA. (I hope you will consider this information and not add to the problem but become part of the solution.)

"Domestic and international wool marketing opportunities for American wool free of poly contaminants do exist. However, we cannot capitalize on these opportunities until we seriously address the problem of poly. It has – and continues – to damage the reputation of all U.S. wool, making it more difficult to market any American wool." Terry Martin, president, Anodyne Inc.

"We have been fighting the problem of polypropylene contamination for years. As a textile industry, we have probably done ourselves a disservice by merely mentioning the problem and not being more proactive in driving it back to the people we buy our wool from." Tim Almond, wool buyer, Burlington Industries Wool Co.

"Low prices for wool result in lessened producer emphasis on contamination, particularly that of polypropylene. Without a concerted effort to reduce this contamination at the grower level, all other efforts beyond the farm gate are less effective." Don Van Nostran, general manager, Mid-States Wool Growers Association

Sources of polypropylene contamination of wool

  • Pieces of twine used for repairs. Once the fraying begins, small shreds of poly infest the wool on animals as they come in contact. Use sisal, wire and other non-poly materials for repairs.
  • Loose edges on feedbags unravel and contaminate wool in the same manner as twine strings and poly tarps. Pick up and dispose of feedbags properly and never package wool in poly feed sacks.
  • Poly contamination of feedstuffs. Current knotting mechanisms on many square balers cut a two-inch tail. This tail stays on the bale or is left on the hay field. Longer pieces are also found, indicating careless management practices. To prevent this type of poly contamination, buy or use only hay that has been baled with wire or sisal twine.
  • Grinding or chopping forage without removing twine. One piece of poly is cut into thousands of small pieces, which contaminate the ground ... and eventually your wool clip. Use poly-free hay for bedding and forage and always remove twine before grinding hay.
  • Carelessness or mismanagement results in environmental contamination. Sheep managed in a contaminated environment are more likely to have contaminated wool. Avoid the use of poly products whenever possible, and promptly pick up and dispose of any poly.
  • Poly tarps used for various tasks. Weathered poly tarps fray, unravel and scatter small pieces of poly. For this reason, wool, in any form, should not be placed on a poly tarp. Use a canvas or nylon tarp instead. Also, do not use poly tarps to scare or direct sheep, as shaking causes poly fibers to fray, fall off and scatter. Be sure to share these messages with your shearers and other working crew members. (Poly tarps were repeatedly identified as a major source of contamination in 2004.)

Contamination of raw materials leads to defective end products

Many contaminated fabrics cannot be corrected. This adds to the cost of wool goods and decreases the value of raw wool. Most poly contamination is found after the wool has been made into fabric. Contaminated fabric can, at times, be corrected by hand, but the process is tedious and costly. What you may not know is that eliminating poly from the American wool clip is both possible and fairly inexpensive. The process involves three basic steps:

  • Removing poly products from your farm or ranch.
  • Banning the use of poly products on your property in the future.
  • Replacing poly products currently in use with more wool- and environmentally friendly substitutes.
Previously titled
Keeping Wool Clean

Was this page helpful?

Related Content from OSU Extension

Ask an Expert

Have a question? Ask an Expert!

Ask an Expert is a way for you to get answers from the Oregon State University Extension Service. We have experts in family and health, community development, food and agriculture, coastal issues, forestry, programs for young people, and gardening.