Editing Rayon (section)

== Environmental impact ==
The [[Biodegradation|biodegradability]] of various fibers in soil burial and sewage sludge was evaluated by Korean researchers. Rayon was found to be more biodegradable than cotton, and cotton more than [[cellulose acetate|acetate]]. The more water-repellent the rayon-based fabric, the more slowly it will decompose.<ref>{{cite journal |last1=Park |first1=Chung Hee |last2=Kang |first2=Yun Kyung |last3=Im |first3=Seung Soon |date=2004 |title=Biodegradability of Cellulose Fabrics |journal=Journal of Applied Polymer Science |volume=94 |page=248 |doi=10.1002/app.20879 |doi-access=free }}</ref> Subsequent experiments have shown that wood-based fibres, like Lyocell, readily biodegrade whereas synthetic fibers such as [[polyester]] do not biodegrade at all.<ref>{{Cite journal |last1=Royer |first1=Sarah-Jeanne |last2=Wiggin |first2=Kara |last3=Kogler |first3=Michaela |last4=Deheyn |first4=Dimitri D. |date=2021-10-15 |title=Degradation of synthetic and wood-based cellulose fabrics in the marine environment: Comparative assessment of field, aquarium, and bioreactor experiments |journal=Science of the Total Environment |volume=791 |page=148060 |doi=10.1016/j.scitotenv.2021.148060 |doi-access=free |pmid=34119782 |bibcode=2021ScTEn.79148060R }}</ref> [[Silverfish]]—like the [[firebrat]]—can eat rayon, but damage was found to be minor, potentially due to the heavy, slick texture of the tested rayon.<ref>{{cite journal |last1=Austin |first1=Jean |last2=Richardson |first2=C.H. |date=1941 |title=Ability of the Firebrat to Damage Fabrics and Paper |url=https://www.biodiversitylibrary.org/item/205820#page/387/mode/1up |journal=Journal of the New York Entomological Society |volume=49 |issue=4 |pages=357–365 }}</ref> Another study states that "artificial silk [...] [was] readily eaten" by the [[Ctenolepisma longicaudata|grey silverfish]].<ref>{{cite journal |last=Lindsay |first=Eder |date=1940 |title=The Biology of the Silverfish, Ctenolepisma longicaudata Esch. with Particular Reference to Its Feeding Habits |journal=Proceedings of the Royal Society of Victoria |series=New Series |volume=40 |pages=35–83 }}</ref>

A 2014 ocean survey found that rayon contributed to 56.9% of the total fibers found in [[deep sea|deep ocean]] areas, the rest being polyester, [[polyamides]], [[cellulose acetate|acetate]] and [[acrylic fiber|acrylic]].<ref>{{cite press release |title=Abundance of microplastics in the world's deep seas |url=https://www.sciencedaily.com/releases/2014/12/141216212253.htm |work=ScienceDaily |publisher=University of Plymouth |date=16 December 2014 }}</ref> A 2016 study found a discrepancy in the ability to identify natural fibers in a marine environment via [[Fourier transform infrared spectroscopy]].<ref>{{cite journal |last1=Comnea-Stancu |first1=Ionela Raluca |last2=Wieland |first2=Karin |last3=Ramer |first3=Georg |last4=Schwaighofer |first4=Andreas |last5=Lendl |first5=Bernhard |date=20 September 2016 |title=On the Identification of Rayon/Viscose as a Major Fraction of Microplastics in the Marine Environment: Discrimination between Natural and Manmade Cellulosic Fibers Using Fourier Transform Infrared Spectroscopy |journal=Applied Spectroscopy |doi=10.1177/0003702816660725 |volume=71 |issue=5 |pages=939–950 |pmid=27650982 |pmc=5418941 }}</ref> Later research of oceanic microfibers instead found cotton being the most frequent match (50% of all fibers), followed by other cellulosic fibers at 29.5% (e.g., rayon/viscose, linen, jute, kenaf, hemp, etc.).<ref>{{cite journal |last1=Suaria |first1=Giuseppe |last2=Achtypi |first2=Aikaterini |last3=Perold |first3=Vonica |last4=Lee |first4=Jasmine R. |last5=Pierucci |first5=Andrea |last6=Bornman |first6=Thomas G. |last7=Aliani |first7=Stefano |last8=Ryan |first8=Peter G. |title=Microfibers in oceanic surface waters: A global characterization |journal=Science Advances |date=5 June 2020 |volume=6 |issue=23 |page=eaay8493 |doi=10.1126/sciadv.aay8493 |pmid=32548254 |pmc=7274779 |bibcode=2020SciA....6.8493S }}</ref> Further analysis of the specific contribution of rayon to ocean fibers was not performed due to the difficulty in distinguishing between natural and man-made cellulosic fibers using FTIR spectra.

For several years, there have been concerns about links between rayon manufacturers and deforestation. As a result of these concerns, [[Forest Stewardship Council|FSC]] and [[Programm for Endorsement of Forest Certification Schemes|PEFC]] came on the same platform with CanopyPlanet to focus on these issues. CanopyPlanet subsequently started publishing a yearly Hot Button report, which puts all the man-made cellulosics manufacturers globally on the same scoring platform. The scoring from the 2020 report scores all such manufacturers on a scale of 35, the highest scores having been achieved by [[Grasim Industries|Birla Cellulose]] (33) and [[Lenzing AG|Lenzing]] (30.5).

{{See also|Microplastics}}

=== Carbon disulfide toxicity ===
Carbon disulfide is [[Carbon disulfide#Health effects|highly toxic]].<ref name="WHO">{{cite book |chapter=Carbon disulfide |pages=71–74 |title=Air quality guidelines for Europe |date=2000 |publisher=World Health Organization. Regional Office for Europe |isbn=978-92-890-1358-1 |hdl=10665/107335 |hdl-access=free }}</ref> It is well documented to have seriously harmed the health of rayon workers in developed countries, and emissions may also harm the health of people living near rayon plants<ref name="WHO" /> and their livestock.<ref name=court>Supreme Court of Alabama. [https://caselaw.findlaw.com/al-supreme-court/1023084.html ''Courtaulds Fibers, Inc. v. Horace L. Long, Jr., et al.''; ''Horace L. Long, Jr., et al. v. Courtaulds Fibers, Inc.''] 1971996 and 1972028. Decided: September 15, 2000.</ref> Rates of disability in modern factories (mainly in China, Indonesia, and India) are unknown.<ref name="SciAm 2009" /><ref name="Monosson 2016" /> This has raised ethical concerns over viscose rayon production.<ref name="SciAm 2009" /><ref name="Blanc" /><ref name="brief" /><ref name="blancbook" /> {{As of|2016|post=,}} production facilities located in developing countries generally do not provide environmental or worker safety data.<ref name="FakeSilk">{{cite book |last=Blanc |first=Paul David |title=Fake Silk: The Lethal History of Viscose Rayon |date=2016 |publisher=Yale University Press |isbn=978-0-300-20466-7 |page=325 }}</ref>

Most global carbon disulfide emissions come from rayon production, as of 2008.<ref>{{cite web |date=April 2008 |url=https://www.dir.ca.gov/dosh/DoshReg/CarbonDisulfide5155-4-08.doc |title=Carbon Disulfide Health Effects Assessment for HEAC discussion |website=DIR.CA.gov |publisher=[[California Department of Industrial Relations]] |access-date=2025-05-13 }}</ref> {{As of|2004|post=,}} about 250&nbsp;g of carbon disulfide is emitted per kilogram of rayon produced.<ref name="large-scale">{{cite journal |last=Blake |first=Nicola J. |date=2004 |title=Carbonyl Sulfide and Carbon Disulfide: Large-Scale Distributions over the Western Pacific and eEmissions from Asia During TRACE-P |journal=Journal of Geophysical Research |volume=109 |issue=D15 |doi=10.1029/2003JD004259 |bibcode=2004JGRD..10915S05B |doi-access=free |page=D15S05 }}</ref>

Control technologies have enabled improved collection of carbon disulfide and reuse of it, resulting in a lower emissions of carbon disulfide.<ref name="UllCell" /> These have not always been implemented in places where it was not legally required and profitable.<ref name="court" /><!--In some cases, 25–30% of the carbon disulfide is lost during the process.<ref name="brief" /> more context-->

Carbon disulfide is [[Volatility (chemistry)|volatile]] and is lost before the rayon gets to the consumer; the rayon itself is basically pure [[cellulose]].<ref name="blancbook" />

Studies from the 1930s show that 30% of American rayon workers experienced significant health impacts due to [[carbon disulfide]] exposure. [[Courtaulds]] worked hard to prevent this information being published in Britain.<ref name="Blanc" />

During the [[Second World War]], political prisoners in [[Nazi Germany]] were made to work in appalling conditions at the Phrix rayon factory in [[Krefeld]].<ref>Agnès Humbert, ''Notre Guerre'' (1946), translated into English by Barbara Mellor as ''Résistance, Memoirs of Occupied France'' [http://www.nysun.com/arts/agnes-humberts-wartime-diary-resistance/86444/ Kitson's review of ''Résistance'' in New York Sun]</ref> Nazis used [[Zwangsarbeiter|forced labour]] to produce rayon across occupied Europe.<ref name="Blanc" />

In the 1990s, viscose rayon producers faced lawsuits for negligent [[environmental pollution]]. [[Emissions abatement technologies]] had been consistently used. [[Carbon-bed recovery]], for instance, which reduces emissions by about 90%, was used in Europe, but not in the US, by Courtaulds.<ref name="court" /> [[Pollution control]] and worker safety started to become [[cost-limiting factors]] in production.

Japan has reduced carbon disulfide emissions per kilogram of viscose rayon produced (by about 16% per year), but in other rayon-producing countries, including China, emissions are uncontrolled. Rayon production is steady or decreasing except in China, where it is increasing, {{As of|2004|lc=y|post=.}}<ref name="large-scale" />

Rayon production has largely moved to the developing world, especially China, Indonesia and India.<ref name="SciAm 2009" /><ref name="Blanc" /> Rates of disability in these factories are unknown, {{As of|2016|lc=y|post=,}}<ref name="Monosson 2016" /><ref name="SciAm 2009" /> and concerns for worker safety continue.<ref name="FakeSilk" />