Clothing and the global toxic cycle
Alkylphenols
Commonly used alkylphenol compounds include nonylphenols (NPs) and octylphenols and their ethoxylates, particularly nonylphenol ethoxylates. NPs are widely used in the textiles industry in cleaning and dyeing processes. They are toxic to aquatic life, persist in the environment and can accumulate in body tissue and biomagnify (increase in concentration through the food chain).[1] Their similarity to natural oestrogen hormones can disrupt sexual development in some organisms, most notably causing the feminisation of fish.[2,3]
NPs are heavily regulated in Europe and since 2005 there has been an EU-wide ban on major applications.[4]
Phthalates
Phthalates are a group of chemicals most commonly used to soften PVC (the plastic polyvinyl chloride). In the textile industry they are used in artificial leather, rubber and PVC and in some dyes. There are substantial concerns about the toxicity of phthalates such as DEHP (Bis(2-ethylhexyl) phthalate), which is reprotoxic in mammals, as it can interfere with development of the testes in early life.[5]
The phthalates DEHP and DBP (Dibutyl phthalate) are classed as ‘toxic to reproduction’ in Europe[6] and their use restricted. Under EU REACH legislation the phthalates DEHP, BBP (Benzyl butyl phthalate) and DBP are due to be banned by 2015.[7]
Brominated and chlorinated flame retardants
Many brominated flame retardants (BFRs) are persistent and bioaccumulative chemicals that are now present throughout the environment. Polybrominated diphenyl ethers (PBDEs) are one of the most common groups of BFRs and have been used to fireproof a wide variety of materials, including textiles.
Some PBDEs are capable of interfering with the hormone systems involved in growth and sexual development.[8] Under EU law the use of some types of PBDE is tightly restricted[9] and one PBDE has been listed as a ‘priority hazardous substance’ under European water law, which requires that measures be taken to eliminate its pollution of surface waters.[10,11]
Azo dyes
Azo dyes are one of the main types of dye used by the textile industry. However, some azo dyes break down during use and release chemicals known as aromatic amines, some of which can cause cancer.[12] The EU has banned the use of these azo dyes that release cancer- causing amines in any textiles that come into contact with human skin.[13]
Organotin compounds
Organotin compounds are used in biocides and as antifungal agents in a range of consumer products. Within the textile industry they have been used in products such as socks, shoes and sport clothes to prevent odour caused by the breakdown of sweat.
One of the best-known organotin compounds is tributyltin (TBT). One of its main uses was in antifouling paints for ships, until evidence emerged that it persists in the environment, builds up in the body and can affect immune and reproductive systems.[14] Its use as an antifouling paint is now largely banned. TBT has also been used in textiles.
TBT is listed as a ‘priority hazardous substance’ under EU regulations that require measures to be taken to eliminate its pollution of surface waters in Europe.[15] From July 2010 and January 2012 products (including consumer products) containing more than 0.1% of certain types of organotin compounds will be banned across the EU.[16]
Perfluorinated chemicals
Perfluorinated chemicals (PFCs) are manmade chemicals widely used by industry for their non-stick and water-repellent properties. In the textile industry they are used to make textile and leather products both water and stain-proof.
Evidence shows that many PFCs persist in the environment and can accumulate in body tissue and biomagnify (increasing in levels) through the food chain.[17,18] Once in the body some have been shown to affect the liver as well as acting as hormone disruptors, altering levels of growth and reproductive hormones.[19,20]
The best known of the PFCs is perfluorooctane sulphonate (PFOS), a compound highly resistant to degradation; it is expected to persist for very long periods in the environment.[21] PFOS is one of the ‘persistent organic pollutants’ restricted under the Stockholm Convention, a global treaty to protect human health and the environment, and PFOS is also prohibited within Europe[22] and in Canada[23] for certain uses.
Chlorobenzenes
Chlorobenzenes are persistent and bioaccumulative chemicals that have been used as solvents and biocides, in the manufacture of dyes and as chemical intermediaries. The effects of exposure depend on the type of chlorobenzene; however, they commonly affect the liver, thyroid and central nervous system. Hexachlorobenzene (HCB), the most toxic and persistent chemical of this group, is also a hormone disruptor.[24]
Within the EU, pentachlorobenzene and HCB are classified as ‘priority hazardous substances’ under regulations that require measures to be taken to eliminate their pollution of surface waters in Europe.[25] They are also listed as ‘persistent organic pollutants’ for global restriction under the Stockholm Convention, and in line with this they are prohibited or scheduled for reduction and eventual elimination in Europe.[26]
Chlorinated solvents
Chlorinated solvents - such as trichloroethane (TCE) - are used by textile manufacturers to dissolve other substances during manufacturing and to clean fabrics.
TCE is an ozone-depleting substance that can persist in the environment. It is also known to affect the central nervous system, liver and kidneys.[27] Since 2008 the EU has severely restricted the use of TCE in both products and fabric cleaning.[28]
Chlorophenols
Chlorophenols are a group of chemicals used as biocides in a wide range of applications, from pesticides to wood preservatives and textiles.
Pentachlorophenol (PCP) and its derivatives are used as biocides in the textile industry. PCP is highly toxic to humans and can affect many organs in the body. It is also highly toxic to aquatic organisms.[29] The EU banned production of PCP-containing products in 1991 and now also heavily restricts the sale and use of all goods that contain the chemical.[30]
Short-chain chlorinated paraffins
Short-chain chlorinated paraffins (SCCPs) are used in the textile industry as flame retardants and finishing agents for leather and textiles. They are highly toxic to aquatic organisms, do not readily break down in the environment and have a high potential to accumulate in living organisms.[31] Their use has been restricted in some applications in the EU since 2004.[32]
Heavy metals: cadmium, lead, mercury and chromium (VI)
Heavy metals such as cadmium, lead and mercury, have been used in certain dyes and pigments used for textiles. These metals can accumulate in the body over time and are highly toxic, with irreversible effects including damage to the nervous system (lead and mercury) or the kidneys (cadmium). Cadmium is also known to cause cancer.[33,34]
Uses of chromium (VI) include certain textile processes and leather tanning[35]: it is highly toxic even at low concentrations, including to many aquatic organisms.[36]
Within the EU cadmium, mercury and lead have been classified as ‘priority hazardous substances’ under regulations that require measures to be taken to eliminate their pollution of surface waters in Europe.[37] Uses of cadmium, mercury and lead have been severely restricted in textiles.[38]
NOTES:
1. Jensen A & Leffers H (2008). “Emerging endocrine disrupters: perfluoroalkyated substances”, International Journal of Andrology, vol 31, pp161-169
2. Baughman GL & Weber EJ (1994). Transformation of dyes and related compounds in anoxic sediment: Kinetics and products. Environmental Science & Technology 28: 267-276
3. Novotný C, Dias N, Kapanen A, Malachová K, Vándrovcová M, Itävaara M & Lima N (2006). Comparative use of bacterial, algal and protozoan tests to study toxicity of azo- and anthraquinone dyes. Chemosphere 63: 1436–1442
4. Novotný et al (2006) op cit.
5. Sendelbach LE (1989). A review of the toxicity and carcinogenicity of anthraquinone derivatives. Toxicology 57: 227-240
6. Wei Y, Han I-K, Hu M, Shao M, Zhang J & Tang X (2010). Personal exposure to particulate PAHs and anthraquinone and oxidative DNA damages in humans. Chemosphere 81: 1280-1285
7. Brigden K et al (2011) op cit.
8. Gregory P (2007). “Toxicology of textile dyes”, Chapter 3 in Christie, R. (ed.) Environmental aspects of textile dyeing, Woodhead Publishing
9. Commission Regulation (EC) No 552/2009 of 22 June 2009, op cit (REACH). Existing restrictions set out in the Marketing and Use Directive (76/769/EEC) were carried over to REACH. Directive 76/769/EEC was repealed on 1 June 2009. Azocolourants were previously restricted under the EU (2002) Directive 2002/61/EC of the European Parliament and of the Council of 19 July 2002 amending for the nineteenth time Council Directive 76/769/EEC relating to restrictions on the marketing and use of certain dangerous substances and preparations (azocolourants), Official Journal L 243, 11.09.2002, pp15-18
10. Pinheiro HM, Touraud E & Thomas O (2004). Aromatic amines from azo dye reduction: status review with emphasis on direct UV spectrophotometric detection in textile industry wastewaters. Dyes and Pigments 61(): 121-139
11. Carvalho G, Marques R, Lopes AR, Faria C, Noronha JP, Oehmen A, Nunes OC & Reis MAM (2010). Biological treatment of propanil and 3,4-dichloroaniline: Kinetic and microbiological characterization. Water Research 44(17): 4980-4991
12. Dom N, Knapen D, Benoot D, Nobels I & Blust R (2010). Aquatic multi-species acute toxicity of (chlorinated) anilines: Experimental versus predicted data. Chemosphere 81(2): 177-186
13. Since 1991, all PCP-containing products sold and used in the EU have been imported (EU production was banned under Directive 76/769/EEC). Now entry number 22 of Annex 17 of the EU chemical law REACH prohibits the marketing and use in the EU of PCP and its salts and esters in products in a concentration equal to or greater than 0.1 per cent. Commission Regulation (EC) No 552/2009 of 22 June 2009, op cit. (REACH)
14. OSPAR (2004). Pentachlorophenol, OSPAR Priority Substances Series 2001, updated 2004, OSPAR Convention for the Protection of the Marine Environment of the North-East Atlantic, OSPAR Commission, London, ISBN 0-946956-74: 31 pp. http://www.ospar.org/documents/dbase/publications/p00138_BD%20on%20pentachlorophenol.pdf
15. Use of TCE is restricted via Entry 34 of Annex 17 of the EU chemical law (Regulation (EC) No 1907/2006 concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH)) to concentrations equal to or greater than 0.1 per cent by weight of product for sale to the general public and in diffusive applications such as surface cleaning and cleaning of fabrics. Commission Regulation (EC) No 552/2009 of 22 June 2009 (REACH) op.cit.
16. Agency for Toxic Substances and Disease Registry (1989) Toxicological profiles for 1,1,2-trichloroethane, United States Public Health Service, Agency for Toxic Substances and Disease Registry, December 1989.
17. Agency for Toxic Substances and Disease Registry (2006) Toxicological profiles for 1,1,1-trichloroethane, United States Public Health Service, Agency for Toxic Substances 18 Disease Registry, July 2006
18. ATSDR (2004) Toxicological profile for copper, United States Public Health Service, Agency for Toxic Substances and Disease Registry, September 2004
19. ATSDR (2005) Toxicological profile for nickel. Agency for Toxic Substances and Disease Registry, US Public Health Service, August 2005
20. ATSDR (2008b) Toxicological profile for chromium, United States Public Health Service, Agency for Toxic Substances and Disease Registry, September 2008
21. Comber SDW, Merrington G, Sturdy L, Delbeke K, van Assche F (2008). Copper and zinc water quality standards under the EU Water Framework Directive: The use of a tiered approach to estimate the levels of failure. Science of the Total Environment 403(1-3): 12-22
22. Guangdong Province (2001). Guangdong Provincial Water Pollutant Emission Limit, DB4426-2001. http://www.gdepb.gov.cn/hjbz/dfbz/200511/P020060728344805222501.pdf
23. MEP (1992). GB 4287-92, the Discharge Standard of Water Pollutants for Dyeing and Finishing of Textile Industry, Ministry of Environmental Protection (MEP), The People’s Republic of China. http://english.mep.gov.cn/standards_reports/standards/water_environment/Discharge_standard/200710/t20071024_111797.htm
24. ATSDR (2008b). Toxicological profile for chromium, United States Public Health Service, Agency for Toxic Substances and Disease Registry, September 2008
25. IPPC (2003). Reference document on best available techniques for the textiles industry, Integrated Pollution Prevention and Control (IPPC), European Commission
26. ATSDR (2008b) op cit.
27. IPPC (2003) op cit.
28. ATSDR (2008b) op cit.
29. DeLaune RD, Patrick WH & Guo T (1998). The redox-pH chemistry of chromium in water and sediment. In Allen HE, Garrison AW, Luther GW, eds, Metals in Surface Waters. Ann Arbor, USA. ISBN:1575040875: 262 pp.
30. Lin C-J (2002). The chemical transformations of chromium in natural waters - A model study. Water air and soil pollution 139 (1-4): 137-158
31. ATSDR (2008b) op cit.
32. Salomons W & Forstner U (1984). Metals in the hydrocycle. Springer-Verlag, Berlin, Heidelberg, New York, Tokyo, ISBN 3540127550
33. Baral A, Engelken R, Stephens W, Farris J & Hannigan R (2006). Evaluation of aquatic toxicities of chromium and chromium-containing effluents in reference to chromium electroplating industries. Archives of Environmental Contamination and Toxicology 50(4): 496-502
34. ATSDR (2008b) op cit.
35. IARC (1990a). Chromium and chromium compounds. In: International Agency for Research on Cancer (IARC) monographs on the evaluation of the carcinogenic risk of chemicals to humans. Volume 49; Chromium, Nickel and Welding. ISBN 9283212495
36. Guangdong Province (2001). Guangdong Provincial Water Pollutant Emission Limit, DB4426-2001. http://www.gdepb.gov.cn/hjbz/dfbz/200511/P020060728344805222501.pdf
37. MEP (1998). Integrated Wastewater Discharge Standard (GB8978-1996). Ministry of Environmental Protection (MEP), The People’s Republic of China. http://www.es.org.cn/download/18-1.pdf (Chinese). http://english.mep.gov.cn/standards_reports/standards/water_environment/Discharge_standard/200710/t20071024_111803.htm (English introduction)
38. IPPC (2003) op cit.