Cotton contaminants

Cotton wool sprinkled with the peroxide (used in guard tubes) will ignite a few s after exposure to moist carbon dioxide. Exothermic interaction of sodium peroxide and carbon dioxide heats the cotton which then ignites in the liberated oxygen [1], Cotton contaminated with peroxide should not be stored under any circumstances as it may ignite with atmospheric carbon dioxide [2],... 

Exposure to endotoxin aerosols also produces phagocyte recruitment vivo. Endotoxins are common cotton contaminants (44). In vitro, they are directly chemotactlc, but in vivo, they may also interact with airway cells to generate chemotactlc factors. 

PMN infiltration also occurs following exposure to some common microbial cotton contaminants (Enterobacter aerogenes (44), Klebsiella pneumoniae or Escherichia coll), but not others (. subtills) (45). Cotton dust extracts pretreated at 80 C and 100 C for 20 minutes cause successively higher leucocyte responses, indicating that the chemotactlc effect is not solely affected by viable bacteria (46). Thus, while the increase seen in PMNs may not, by itself, represent a pathological alteration, it could be of importance in the later development of pathological effects. 

Mechanically harvested cotton, either with cotton picker machines (cotton burr remains attached to the stalk) or with stripper machines (cotton burr is removed along with the seed cotton), can contain more trash and other irregularities than hand-harvested cotton. However, according to Cotton contamination surveys by the International Textile Manufactures Federation (ITMF), the most contaminated cottons originate from some of the countries where cotton is hand-picked, whereas some of the cleanest can be sourced in the USA where cotton is machine harvested [34]. Most of the mechanically harvested cotton is harvested with cotton pickers ( 75% in the United States and all in Australia). 

Even when confined in the closed cell and subjected to the isothermal storage test performed at a T, of 65 °C, 0.4 g of collodion cotton contaminated by metals, above referred to, started the autocatalytic reaction, though faintly, about 12.8 d after the start of the isothermal storage test. The sample was found to be yellow and gave off the odor of nitrogen dioxide after the test the inside of the cell was found to be pressurized besides. 

Figure 127. Comparison of the plot of In versus l/Ti made with seven combinations of the value of InZl/ with that of // which are each determined for seven induction periods, of the autocatalytic reaction, of 0.4 g each of seven samples of collodion cotton (11.75 % N), contaminated by metals, confined each in the closed cell and subjected each to the isothermal storage test pcrfomied at each 7", in the range of 66.95 to 90.08 C with mutual intervals of 1 5 K, recorded each for the time, At, from the insertion of each cell into the isothermal storage testing device till the start of the autocatalytic reaction of collodion cotton contaminated by metals at the corresponding T with, the plot made for 0.4 g each of nine samples of normal collodion cotton 12.19 % N) placed each under the same conditions as the former, fhe latter plot is quoted from Fig. 126, for comparison.

Cotton yam is dyed in package machines and the dye exhausted by increasing the temperature and adding salt. The dye must be completely dissolved when preparing the dyebaths to avoid contamination with undissolved dye in the yam package. The increased avaUabUity of the prereduced Hquid dyes and the improved quaHty of sodium sulfide have reduced this problem. Incorrectly dissolved dye was previously the cause of most faulty dyeings. 

Laughlin J, Gold RE. 1987. The vaporization of methyl parathion from contaminated cotton fabrics. Textile Chemist and Colorist 19 39-42. 

Pesticides used on crops grown on the test site in previous seasons may also have an impact on the outcome of a field residue trial. Carryover of prior pesticide applications could contaminate samples in a new trial, complicate the growth of the crop in a trial, or cause interference with procedures in the analytical laboratory. For this reason, an accurate history of what has transpired at the potential test site must be obtained before the trial is actually installed. The protocol should identify any chemicals of concern. If questions arise when the history is obtained, they should be reviewed with the Study Director prior to proceeding with the test site. In most annual crop trials, this will not be a significant issue owing to crop rotations in the normal production practices, because the use of short residual pesticides and different chemical classes is often required for each respective crop in the rotation. However, in many perennial crops (tree, vines, alfalfa, etc.) and monoculture row crops (cotton, sugarcane, etc.), the crop pesticide history will play a significant role in trial site selection. 

Foot exposure of workers can be measured by using socks as dosimeters or anklet dosimeters worn under ordinary socks. Usually an ordinary sock or anklet bought at a retail store will suffice for the dosimeter. As with whole-body dosimeters, the sock material should be 100% cotton but may be other materials. Pre-washing the socks or anklets prior to use in the field may be necessary if analytical interferences are found in the sock material. The socks or anklets should be put on the volunteer using procedures similar to those already described in order to avoid cross-contamination of the sock dosimeter. 

In 1971-75, the health of a group of 2473 children aged 1-14 was studied in several farms of the Khorezm Oblast (Uzbekistan), where HCH, phosalone and DEF were used to grow cotton. Overall illnesses among children in the region where the air was contaminated with pesticides were three times higher than in the control region [A85]. 

Holland, R. D. Rafii, F. Heinze, T. M. Sutherland, J. B. Voorhees, K. J. Lay J. O., Jr. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometric detection of bacterial biomarker proteins isolated from contaminated water, lettuce and cotton cloth. Rapid Comm. Mass Spectrom. 2000,14, 911-917. 

In both research and practice, critical localised concentrations of metal contamination can be difficult to detect. Potassium hexacyanoferrate(II) (10.80) gives an intense deep blue coloration with iron(III), permitting extremely sensitive detection of tiny iron spots even by visual inspection. It is recommended as a quality control measure on batches of cotton destined for bleaching [237]. However, in view of the random distribution of metal traces, even the most sensitive test cannot guarantee freedom from contamination throughout a batch of goods to be bleached. 

The possible benefits of prescouring to remove such contaminants should also be considered. Alkaline pretreatments, including boiling off of cotton, have a profound effect on AOX values after chlorite bleaching (Tables 10.21 and 10.22). It can be beneficial, from the viewpoint of both AOX and whiteness, to follow a chlorite bleach with a peroxide treatment. Linen yarns after an alkaline scour and chlorite bleach gave a whiteness value of 63.9 with an unacceptably high AOX value of 8.0 ppm. These results were improved to 78.5 and 1.2 ppm respectively after peroxide treatment [224]-... 

In a factory manufacturing organo-iron and organo-manganese catalysts, use of cotton waste to mop up a spill of dilute hydrazine solution led to a spontaneous fire later. The fire was attributed to onset of rapid metal-catalysed decomposition of the hydrazine after sufficient water had evaporated from the waste, the traces of heavy metals originating from dust contamination, etc. 

Tolerance of GM seeds in non-GM varieties ranges from 0 to 5% in different countries (ISF, 2004). It is widely agreed that it is impossible to maintain or guarantee that seed from a crop such as maize, soybeans, canola or cotton is absolutely free of GM seeds. It should be reiterated that IFOAM opposes mandatory testing for GM contamination and proposes that organic farmers do not have to prove that their crops are GM-free (IFOAM, 2002). The International Seed Federation (ISF) proposed that its 70 member countries... 

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