In this post, we'll be talking about the clothing fiber we are most familiar with and love, cotton. Cotton is an extensively traded commodity and a key material in the multi-billion dollar fashion industry. The white, fluffy fiber takes up about 40% of the world's textile industry (1), and about 26.2 million tons were produced worldwide in 2013/14 across 33.1 million hectares of land (2). A commonly held notion is that cotton, a natural fiber, is better for the environment as compared to synthetic fibers such as viscose and polyester (which we're going to talk about in a future post – keep a lookout!). But the truth of the matter is, cotton's environmental impact can be just as negative as its synthetic cousins. This is mainly because, in order to keep up with such a large demand, the production of cotton mostly uses chemicals that are harmful pollutants for the environment.
Source: WWF
Only 2.4% of the world's arable land is reserved for cotton, yet cotton accounts for 24% of the world's insecticide demand and 11% of pesticide sales (3). In the US, herbicides are used most extensively. Herbicides are applied to 93 percent of its 13,280,000 planted acres for cotton, with glyphosate and dicamba being the most popular varieties (4).
The former is mostly used on genetically modified herbicide-tolerant (GMHT) cotton. GMHT crops make weed control cheaper and more effective, with streamlined herbicide applications and a reduction in the risk of weed control failures (5). Though the herbicide is effective in increasing crop yield and is often touted as the "least toxic" synthetic herbicide, it has been found to cause negative effects on non-target invertebrate populations such as aphids – which are a primary food source for beneficial insects – and earthworms – which help to naturally increase soil nutrient availability and improve soil structure (5). Application of glyphosate herbicides has also been found to result in a 1592 percent rise in soil nitrate concentrations and a 127 percent increase in phosphate, imposing possible hazards for leaching into streams, lakes, and groundwater aquifers (6). This leaching of nutrients might cause eutrophication – a phenomenon whereby bodies of water become overly enriched, causing excessive algae growth – which endangers aquatic ecosystems and deteriorates water quality.
Eutrophication results in hypoxic water conditions, causing aquatic animal and plant life to die. Source: Conserve Energy Future
The use of the latter, dicamba, is uber controversial. Developed by the agrochemical giant Monsanto, dicamba has been found to destroy plants that are not genetically modified to resist it. This is exacerbated by the herbicide's volatility, which means that even if the herbicide is only applied to selected crops, it easily becomes airborne and consequently drifts away, killing natural vegetation and surrounding unprotected fields. It has also been found that the combination of both glyphosate and dicamba increases the volatility of the latter, and a study shows that the mixture is dangerous to amphibian lives (7) – which are in the process of an ongoing extinction as we speak.
There is still so much to talk about the damaging effects of cotton crop production not only to the environment and animal lives, but also to human health – but we think this post is enough of an information bomb for you. In a future post, we will be diving deeper into the health cost of cotton production – stay tuned!
Yours truly,
Katya (owner of one too many cotton t-shirts and pairs of jeans)
References
1. Proto, M., Supino, S., & Malandrino, O. (2000). Cotton: A flow cycle to exploit. Industrial Crops and Products, 11(2-3), 173-178. DOI:10.1016/s0926-6690(99)00060-6
2. Farnworth, G. (2015). Cool Cotton: Organic Cotton and Climate Change (Publication). Bristol: Soil Association. Retrieved from https://www.soilassociation.org/media/11662/coolcotton.pdf
3. World Wildlife Fund. (2006). Thirsty Crops: Our food and clothes: Eating up nature and wearing out the environment? (Publication). The Netherlands: WWF. Retrieved from https://www.worldwildlife.org/publications/thirsty-crops-our-food-and-clothes-eating-up-nature-and-wearing-out-the-environment
4. United States Department of Agriculture. (2019). 2019 Agricultural Chemical Survey: Cotton (Publication). USDA. Retrieved from https://www.nass.usda.gov/Surveys/Guide_to_NASS_Surveys/Chemical_Use/2019_Field_Crops/chem-highlights-cotton-2019.pdf
5. García-Ruiz, E., Loureiro, Í, Farinós, G. P., Gómez, P., Gutiérrez, E., Sánchez, F. J., . . . Castañera, P. (2018). Weeds and ground-dwelling predators′ response to two different weed management systems in glyphosate-tolerant cotton: A farm-scale study. Plos One, 13(1). DOI:10.1371/journal.pone.0191408
6. Gaupp-Berghausen, M., Hofer, M., Rewald, B., & Zaller, J. (2015, August 5). Glyphosate-based herbicides reduce the activity and reproduction of earthworms and lead to increased soil nutrient concentrations. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4542661/
7. Soloneski, S., Arcaute, C. R., & Larramendy, M. L. (2016). Genotoxic effect of a binary mixture of dicamba- and glyphosate-based commercial herbicide formulations on Rhinella arenarum (Hensel, 1867) (Anura, Bufonidae) late-stage larvae. Environmental Science and Pollution Research, 23(17), 17811-17821. DOI:10.1007/s11356-016-6992-7
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