Location: Cotton Ginning ResearchTitle: What research is happening to help prevent contamination of U.S. cotton?
Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Abstract Only
Publication Acceptance Date: 2/7/2017
Publication Date: 6/1/2017
Citation: Whitelock, D.P., Byler, R.K., Pelletier, M.G., Thomasson, A. 2017. What research is happening to help prevent contamination of U.S. cotton?. National Cotton Council Beltwide Cotton Conference, January 4-6, 2017, Dallas, TX. p. 435-440.
Technical Abstract: U.S. cotton is considered to have some of the lowest levels of contamination in the world. However, that reputation is in jeopardy as complaints of contamination from domestic and foreign mills is on the rise. Cotton contamination can be classified under four major categorizes: fabrics and strings from plastics and natural fibers, oils and chemicals, organic matter, and inorganic matter. Of particular concern are plastic contaminants – plastic trash that collects in cotton fields, black plastic film used as mulch in fields, plastic twine typically used for hay baling, and yellow plastic film used for round module wrap. The current efforts by the U.S. cotton industry to prevent cotton contamination include: education, prevention, and research on areas of detection and extraction. Cotton contaminants are typically introduced in the field. The first line of defense against cotton contamination is the people working in the industry. Current education and prevention efforts are spearheaded by the National Cotton Council, Cotton Incorporated, and the National Cotton Ginners Association. This campaign includes educating all sectors of the cotton industry on the seriousness of the contamination issue and encouraging the industry to be diligent in efforts to prevent contamination. The NCC has created a “Contamination-Free Cotton” web page (www.cotton.org/tech/quality/contamfree.cfm) with links to contamination prevention guidelines for growers, gins, and warehouses; contamination prevention posters; and studies and publications on minimizing contamination (Figure 1). Many articles have appeared in the farming and industry popular press. Also, industry experts are getting the word out at local, state, and national industry meetings. If contamination can be prevented from entering the cotton stream before the module, a major part of issue would disappear. When contaminants do slip into the cotton stream, they must be detected and extracted. There are major efforts underway at the USDA-ARS cotton ginning research laboratories and Texas A&M University to do just that. One such project at the USDA-ARS Cotton Production and Processing Research Unit in Lubbock, Texas involves detecting plastics in the field. One method uses infrared light to detect plastics that heat more readily in the sun than the surrounding cotton plants (Figure 2). Another method detects plastics in the field based on differences in color between some plastics and cotton plants (Figure 3). These methods would likely be incorporated as a harvester mounted device. Researchers at the USDA-ARS Cotton Ginning Research Unit in Stoneville, Mississippi are evaluating current gin extractors and cleaners to understand their contamination extraction capabilities. They have found that current extractors (e.g. stick machines) remove about 56% of plastics, mainly the heavier and larger pieces. Current cylinder cleaners remove only about 10% of plastic contaminants and these are usually the lighter, smaller pieces. After the gin stand, very little contamination is removed (~4%). They also found that fibrous materials, like hay bale twines (Figure 4) that are a major problem at the spinning mill, are not removed. To detect plastics before they enter the gin, researchers in the Department of Agricultural and Biological Engineering at Texas A&M University are working on a camera based system to identify yellow round module wrap that enters at the module feeder (Figure 5). Their system was tested at two gins in 2016. Images from those tests identified pieces of module wrap entangled on the feeder cylinders and some pieces slipping through the cylinders with the cotton stream. At the USDA-ARS Southwestern Cotton Ginning Research Laboratory in Mesilla Park, New Mexico, scientists are using spectral imaging with ultraviolet fluorescence and visible, near-infrared, and short-wavelength in