Eco-friendly textiles

Eco-friendly textiles

The textile industry is considered as the most ecologically harmful industry in the world. The eco-problems in textile industry occur during some production processes and are carried forward right to the finished product. In the production process like bleaching and then dyeing, the subsequent fabric makes a toxin that swells into our ecosystem. During the produc�tion process controll�ing pollution is as vital as making a product free from the toxic effect. The utilization of rayon for clothing has added to the fast depleting forests. Petroleum-based products are harmful to the environment. In order to safeguard our environment from these effects, an integrated pollution control approach is needed. Luckily there is an availability of more substitutes.

Eco-friendly fabrics

Hemp, wool, organic cotton, soy silk, bamboo fabrics, jute, corn fiber etc are considered as eco-friendly fabrics due to their availability from nature with out any harmful effects of chemical or toxics. Moreover, as compared to other synthetic fibers they are available in a cheaper rate.

Textile chemical processing is shifting to undeveloped countries due to easy availability of low-cost labor and minimum eco-restrictions. This is also because of various manufacturing processes undertaken by developed countries and awareness about the related health hazards amongst these people. However, such measures though may be beneficial for the employer, but they are unsafe for the society and therefore their control is very much needed. So, various functions related to the textile industry which are considered as major factors for eco-friend�liness are mentioned below:

Cultivation of cotton

Cotton cultivation requires large amount of pesticides, fertilisers and water. With the increasing use of cotton, 22.5 percent of insecticides are used globally for it. Subsequently, this increasing use of cotton requires approximately 257 gallons of water for one T-shirt. Pesticides are biologically active chemical compounds, which curtail the growth of organism like bacteria, fungus, algae, insects, etc. Averting the augmentations of these unwanted organisms improve the crop yield make the quality of fibre better. Water if utilized in too much quantity in irrigation of cotton, can increase the salinity of land and thereby decrease its fertility.

Spinning

In the spinning process, individual fibres float in the air and thus pollute the atmos�phere in the spinning department. Such floating fibres are dangerous to human beings who inhale it. To minimize the effect of these floating fibres or impurities, the humidified air which is scattered in the spinning department is filtered so as to remove these floating impurities from the air.

Sizing

In the sizing function, starch is used in sticky paste form to the yarn to enhance its strength and abra�sion resistance. The starch paste consists of preservations in order to protect it from the attack of micro�organisms. Some preservatives like pentachlorophenol, which are obtained from phenolic and/or chlorinated compound, possess a toxic effect on human skin. Hence, such preservations should be avoided. Utilizing a synthetic starch decreases the use of such preservations, thereby decreasing the health hazards likely to occur because of phenolic and/or chlorinated preservative.

Loom shed

There are two types of pollutants created by the loom shed, namely floating particles like fibrous substances and size particles and noise pollutions. If proper measures are not taken during the weaving operations, oil stains are formed. Before textile chemical processing, these oil stains are removed in subsequent gray folding department by applying stain remover. Hence, measures are taken to lessen oil stains in the cloth and probably the application of carbon tetra chloride based products should be avoided in stain remover and other textile products.

Textile processing regarded as non-eco-friendly
Use of chemicals like potassium dichromate, sodium hypochlorite or peroxide and sodium hypochlorite in the preparation process of desizing, scouring and bleaching with their related wash-off stages, produces heavy Biological Oxygen Demands (BOD) in the effluents. Chlorine is not used in bleaching because it creates halogenated organic substances, of which some are suspected to be carcinogenic, e.g., chloroform.

Table-1 indicates that the maximum use of water and production of Biological Oxygen Demand (BOD) in effluent process-houses of composite mills comes from desizing, scouring and bleaching procedures.

For decreasing BOD, it is recommended to choose the size recipes offering a low COD (Chemical Oxygen Demand) and BOD value. A change from pure starch to synthetic starch decreases BOD because of starches by approximately 90 per cent.

Wool industry uses chlorine� based compounds for anti�-shrinking dealing, and such practice also generates toxic effluent. For removing rust stains in bleaching, before bleaching the cloth is treated with oxalic acid. The oxalic acid is lethal to aquatic organisms and it increases COD and BOD to a significant level.

Peroxide bleaching requires a stabilizer to ensure identical and monitored bleaching during the bleaching operation. Optional stabilizers such as Aminio Tri Methylene Phosphoric Acid (ATMP), Hydroxy Ethy!idine Disphosphonic Acid (HEDA), Diethylene Triaminc Penta Methylene Phosphoric Acid (DTPMP) and Ethylene Diamine Tetra Methylene Phosphoric Acid (EDTMP) are also being suggested as peroxide stabilizers.

Dyeing

German legisla�tion consumer goods ordinance states that, "No articles of dresses (textiles, shoes, leather) and bed linen can be put in trade, if they have been colored with azo dyes that can release one of the twenty named amines". Currently the list has been extended to 24 amines. The prohibition includes a variety of other commo�dity goods like leather components for furniture, seat covers, etc. The prohibited amines have been categorized as amines of the MAK Group-III A 1 and III A 2.

MAK Group III AI: (workplace exposure):
Carcinogenic amines: Benzidine, 4-chloro-o-toluidine, 2-naphty�lamine and 4-aminodiphenyl.

MAK Group III A 2:
These materials are tested only on animals and they have been proved carcinogenic. A variety of amines in these types are: a-toluidine, o-dianisidine, o-tolidine, o-aminoazotoluene, p-chroanneline, 3, 3' dichlorobenzidine, 2-amino�-4-nitrotoluene and 2, 4-toluylene� diamine. This group also includes materials that may perhaps produce health hazards.

Some dyes form carcinogenic amines on reduction in dyeing and hence they require to be strictly evaded as per stipulation in a number of countries, considerably for increase of BOD/COD and hence, these dyes also need to be avoided for use in dyeing. Most of the known producers have stopped making and marketing dyes creating carcinogenic amines.

High fastness direct dyes should be chosen in such a way that applying copper or chromium salts in their dyeing is avoided. Cationic dye fixing agents utilized for direct dyes and reactive dyes should have low formaldehyde content and low BOD. During reactive dyes the use of urea needs to be lessened. Instead of extremely contaminated sodium sulphide other agents such as hydrol or hydroxyl acetone should be used while dyeing with sulphur dyes.

In polyester dyeing, the carriers and leveling agents utilized should not be supported with chlorinated or phenolic composites. Carriers supported with chlorobenzene are highly toxic and more or less carcinogenic. The leveling agents that contain chlorobenzene as well as per chloroethylene or trichloroethy�lene are carcinogenic compounds, and therefore they should be avoided.

With regards to the direct, vat, sulphur and reactive dyes, dyeing processes need huge amount of salt to achieve good exhaustion of dye-bath. This leads to an increase in the dissolved salts in effluent water. Therefore, new dyes are being made, which would need less salt dilution for achieving dye fixation.

Printing

As in the case of dyeing, in printing too, colors chosen should be non-toxic and not based on for�bidden amines. Dyes with high fixation properties and modi�fied printing process requiring fewer wash�outs are recommended to be applied in printing. Use of kerosene in pigment printing has been significantly decreased, but it should be totally removed.

The use of urea has also been lessened by substituting it with other ingredients and modifying the printing methods. Citric acid in disperse prints should be substituted by optional chemicals. For nylon fabric printing phenol is utilized to a considerable extent, therefore it is suitable to replace it by diethy�lene glycol. Application of formaldehyde based on fixers for enhancing fastness of pigment prints should be limited so as to decrease free formaldehyde in final fabric.

Finishing

Chemical formaldehyde based cross-linking agents applied to cellulosic textiles for crease resis�tance and dimensional stability are the most toxic chemicals. Free formaldehyde may be discharged from resin-finished fabrics either because of un-responded formaldehyde in the product in cross-linking or while storage of the finished fabrics. Many countries set various tolerance limits for free formaldehyde according to the end use of the treated fabrics or garments. Presence of formalde�hyde in the atmosphere and in waste-water is regarded as highly toxic and to overcome this trouble, formaldehyde scavengers (chemi�cals which neutralise toxic effects of formaldehyde) are to be used.

Among the various procedures, finishing presumes significant importance because the value addition is understood by functional finishing of cotton in fabric or garment form to reveal advantageous properties. Some of the most important finishes are easy care, durable press, wrinkle-free finishes, softening and enzyme/ bio-finishing.

Approaches for eco-�friendly practices

Any organized approach to move production towards clean production should have the following steps:

Prevent: To 'prevent' is to give up a process or product in favor of noticeably improving the environmental situation.

Decrease: This can be attained by reducing the pollutant load, exhaustion and fixation of dyes close to 100 per cent and responding to water and energy requirement.

Re-utilise: Re-utilisation of the dye bath is a vital deliberation under the pressure of dwindling resour�ces. This has now turned into pragmatism because of addition of new auxiliaries, modern filter technology and spectrophotometers that calculate the substance of the dye in the dye bath accurately.

Recycle: This recycling of natural fibres is achievable, but it has a limitation of application because of natural degradation. Synthetic fibres can be recycled by melting down and regranulating with or without applying fresh granules. This perhaps is most acceptable to 'green' organizations, but is limited due to lack of uses for the material recycled.

Eco-factors

With respect to clothing textiles, the phrase 'ecology' can be classified into three groups:

1) Production ecology, which includes:
.Cultivation and harvesting of natural synthetic fibres.
.Production of regenerated and synthetic fibres.
.Production of yarns, twisted threads and fabrics.
.Finishing.

Garment production by using fertilizers, growth regulators, crop protection agents like pesticides and a range of textile chemicals, auxiliaries and finishing agents.

2) User Ecology, which is related to the clothing textiles and the substances that give them beauty and performance charac�teristics during application.

3) Disposal Ecology, which refers to the disposal of textiles after application i.e., to-recycling com�posting, dumping or incinerating in a manner that ascertains the least probable environment effect.

The related factors for eco-standards are:
Formaldehyde, pesticide, carcinogenic dyestuff, skin neutrality, heavy metal content, -pH, fastness to perspiration.

Eco-Iabelling

Eco-standards and eco-Iabels are quickly started to have significance in arrange to have a successful expert and market promotion in the apparel and textile industry. For the delivering eco-Iabels particular standards should be set, i.e., these measures are developed on analysing the product's whole lifecycle beginning with the selection of raw materials progress�ing through the stages of produc�tion, packaging, distribution, use and disposal after utilization.
Some of them are as described below:

OEKO- TEX Standard 100:

For research and testing in the field of textile ecology, the OEKO- TEX standards were given by the Austrian Textile Research Institute and the German "Hohenstein Research Institute".

The OEKO-TEX standards have described a variety of norms and limit values for different classes. They can be described as follows:
.Product class I: Defined for babies and infants up to two years of age.
.Product class II: This class is defined for textiles that come into direct contact with the skin and cover a large part of its surface, during usage.
.Product class III: The class includes textiles which do not come into direct contact with the skin or cover only a small part of its surface during application.
.Product class IV: This class covers furnishing materials which are used for decorative purposes.

MST (Markenzeichen Schadstoffgeprufter Textile):

This is a product label, which is to be used for products that are made in Germany and referring only properties of textiles.

Trademarks for textile tested harmful substances:

MUT: This is a trademark for textiles that are made by environmentally sound protection methods (VVUT). It needs acquiescence of certain rules in their manufacture.

GUT: This eco-Iabel was established by well-known companies in European carpet industry. GUT exists for "Gemeinschaft Umwelt�freundlicher Teppichboden." It is an association for environmentally friendly carpets with an objective of maximizing textile floor-coverings and their protection cycle.

GuW: It is a seal of Eco-friendly Fur�nishing Fabric Association.

CLEAN FASHION: It is an Eco-Iabel introduced by private companies related to textiles.

STEILMANN: This is an Eco-Iabel of the most prominent German Textile Company.

GREEN COTTON: A label based on an internal evaluation system that considers social, ecological and toxicological values.

ECO MARK: This is an Indian eco-Iabel.

Function of ISO 14000

The ISO 14000 series of international standards have been made to tackle issues dealing with environment today. The main aims of ISO 14000 are:
.Protection of natural resour�ces.
.Reduction and abatement of waste and emission.
.Constant improvement in environmental performances.
.Efficiency in process by application of the best available technology.
.Compliance to national and international environmental laws and convention.

Eco-management

In India each state has its own pollution control authority. This authority mainly deals with water pollution by textile industry. The aim is to ensure that the effluent water being discharged into city sewage, stream, river or sea is not harmful to human, animal or plant life. In order to get the parameters of effluent water to suitable standards, the effluents are treated by effluent treatment plant.

For controlling air and noise pollution in India, the pollution control authori�ties have taken subjective steps. It can be stated that basically no steps are taken by pollution control authorities to control air and noise pollution in textile industry.

In the case of toxicity of textile products, the awareness is increasing in India due to rigid rules and regulations being set up by developed countries. It has forced Indian producers to fulfill these rules and regulations for attracting exporters.

In eco-management systems followed in textile industry, water utilized for washing is re-used. Also the caustic soda used in mer�cerisation is recovered and re-used.

Textile industries use the maximum amount of water. In the industries, water is contaminated with different chemicals and auxiliaries, which are used for producing textile goods. These chemicals are non-biode�gradable and their elimination before releasing the water is important. The polluted water is unsafe for fauna and flora due to high temperature, odors, turbidity, colors and toxic chemicals.

Controlling water pollution:

Water pollution is controlled by treating the effluent water in three ways:
a. Primary treatment includes neutralization and elimination of suspended solids by sedimentation, flotation, flocculation and coagulation techniques.
b. Secondary treatment process is done by the presence of micro-organism developed at the surface of sewage, sludge in the presence of chemi�cal nutrients such as urea and super phosphates.
c. Tertiary treatments include:

Chemical oxidation: Some inorganic from insolubles precipitate over restricted ranges of pH.

Carbon oxidation: Activated carbon has a surface area, which can absorb a huge quantity of organic materials. Use of carbon can be reactivated; it is extremely useful in eliminating the pigments and dyes, which cannot be eliminated by coagulation. Several limits of various wastes in water are given in Table 2.

Management system

For putting into practice the various measures for eco�-friendly process of textile unit, the management has to finalize its clear-cut eco-policy. It should recognize that for proper implementation of these measures additional cost would be involved. As in the case of other costs there should be constant attempts to decrease these eco-costs, but at the expense of eco-standards the textile unit needs to maintain.

Conclusion

Textile industry plays a vital role in the Indian economy. It constitutes nearly 30 per cent of India's exports. Globalization of Indian textile industry makes it necessary to analyze its production techniques, procedures and product qualities to satisfy all international eco-standards.

In different textile production processes, steps should be taken to ensure that these processes are done chemically, but do not create any toxic effects. For making sure that the effluent created complies with the standards set by effluent control authorities, appropriate changes in recipes should be made, effluent treatment plants should be set and re-use of effluent wherever viable should be made. The process of management should be designed in such a way that proper control on choosing and purchase of input materials are inbuilt in the system itself. The cost of effluent treatment is measured as inevitable. Any effort to decrease this cost should not be made by diluting' eco-standards. Suitable audit system should also be introduced by textile units, which ensure that eco�-standards are realized.