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  • 2.4.3-COTTON VALUE ADDITION-WHAT PROPORTIONS OF BALES FROM DIFFERENT ORIGINS ARE CONTAMINATED

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  • What proportions of bales from different origins are contaminated?

    Chapter 2 - Cotton value addition - Extraneous contamination in cotton

     
     

    Extraneous contaminants are found in cotton from all origins, without any exception. Not one single cotton shipment was found to be totally free from contamination in the last eight years. However, raw cotton bales from different countries differ in the degree of contamination. Broadly, cottons from 15 origins can be classified into 3 groups – group I with low contamination, group II with medium levels of contamination, and group III with high level of contamination – as can be seen in table 2.2.


    2.4.3-en
    Source: M.N. Vijayshankar, Vice President, PT Apac Inti Corpora, Semarang, Indonesia.

    All machine-picked origins are classed in the group of the least contaminated origins; China is supposedly the only hand-picked origin in that group.

    Contamination with foreign matter is more serious with hand-picked cottons. Cotton gets contaminated during picking, storage, handling or transport of seed cotton. A major cause of contamination by plastic strings is the use of fertilizer bags made of woven plastic for picking and handling of seed cotton. As a result, hand-picked cottons in general, and those from India and Africa in particular, are discounted in the international market despite the fact that cotton spinners prefer the characteristics of the hand-picked cottons, which are cleaner, with fewer neps and a lower short fibre content, than mechanically harvested cottons.

    It was also observed that there is a wide fluctuation in the level of contamination between shipments of the same type of cotton from the same origin, depending on ginning and growing conditions.

    Typical contaminants observed are human hair, animal hair, cloth pieces, yarn pieces, polypropylene, polythene, plastic strings, bird feathers, metal parts, jute, ramie, bamboo, cable, rubber, newspaper, mint wrappers, wood, long bark, weeds and so on. The sizes of contaminants vary from fine hair or polypropylene weighing a few micrograms to ginning machine parts weighing as much as 15–20 kg.