Cotton effect | Cotton industry effect on the environment

 

Cotton effect

The cotton effect is a characteristic change of optical rotary scattering and/or circular bipolarity around the absorbing band of a substance. In a wavelength region where light is absorbed, first, the absolute wavelength of the optical rotation changes rapidly, the absorption exceeds zero in the maxima, and then again rapidly changes with the wavelength but in the opposite direction. This phenomenon was discovered in 1895 by the French physicist Aime Cotton. The cotton effect is said to be positive when the optical rotation first increases as the wavelength decreases, and negatively when the rotation decreases first. The beta-sheet-like protein structure shows a positive cotton effect.

Cotton Industry Effect on the Environment

Cotton is the most widely used and profitable non-food crop in the world, a product that employs more than 250 million people and accounts for 7% of all labor in developing countries. Cotton is still the most used textile after polyester. Worldwide, 35 million hectares of cotton are cultivated. Since cotton is in such high demand, its production brings many issues related to durability and ethical production. Let's talk about some of them here.

i. Water consumption

Cotton production requires water, in fact, plenty of water. It takes about 2700 liters of water to make a single cotton T-shirt. But wait, there's more. Not only is cotton water-intensive for production, but it is also assumed that this material is the most water-efficient of all agricultural products for irrigating surface and groundwater often cotton fields. This leads to the loss of freshwater as a result of invisible management and sustainable efforts.

ii. Pesticide pollution

Only 2.4% of the world's arable land is planted with cotton, 25 percent of the world's insecticides, and 18 percent of pesticides are used to grow it; which makes cotton production the number one consumer of pesticides in the world and has some fatal consequences. Every year, 43 million tons of pesticides are blown into the air from cotton fields. The region around the Aral Sea suffers from one of the highest rates of throat cancer in the world as a result of air pollution. In the cotton region of Brazil, rainwater contains 19 different pesticides, 12 of which were common in cotton production. However, pesticides do not only affect air quality. Insecticide use affects water pollution and the causes of pollution and both animals and humans.

iii. Fabric production

Before turning into cotton T-shirts, reusable shopping bags, bedsheets, or anything else, it is necessary to make a fabric. To do this, the cotton is processed with several dyes and chemicals. The river blue documentary has done an amazing job of showing how these chemicals are often disposed of anonymously through pipes and tunnels and dumped directly into the sea and river. A big problem in many garment factories, and especially in fast fashion, is that the health and environmental impacts of workers on the water near these chemicals are not being prioritized. Proper water filtration and chemical waste management are costly and often completely neglected.

iv. Fabric Finishing

Improving COD and BOD, de-sizing, and wet finishing operations is crucial to prevent and reduce contamination. The most notable natural fiber used in textiles is cotton and to size, it is often used as starch and derivatives. The contaminated concept of starch-sized cotton fabric raises the BOD values ​​of wastewater flow and at the same time, this wastewater constitutes about 50% of water pollution. Contaminants present in textile fibers such as oils, waxes, lubricants, etc., which are underlying and then attached, are expelled by scouring to refine and hydrophilic the fibers. Cotton scouring is grown at a high temperature of 120 ˚ C in a vigorous basic solution and is conducted in moderately alkaline conditions with polyester detergent. The alkalinity values ​​of TDS, COD, BOD, and wastewater are very high because the contaminants are degraded and converted to soluble forms. Highly toxic chlorinated by-products caused by hypochlorite, one of the earliest bleaching agents, have been reduced to absorbable organic halogens (AOX). Over the past decade, other agents have replaced hydrogen peroxide (H2O2) hypochlorite and chloride. Although H2O2 is considered an environmentally friendly choice, the phosphate-based stabilizers that have to be used together increase the COD and TOC content of wastewater. If neutrality is required after the bleaching process, the amount of salt released will be significant. Fabric residues require some chemicals to expel H2O2 residues, especially reactive dyeing, which accelerates the hydrolysis of the dye.