All examination and surgical gloves are designed for the sole purpose of protecting people’s hands and vary greatly across the process of manufacturing, design and technological advancements. While most glove materials, such as nitrile and latex, look and feel the same, they are made to be used throughout a wide range of industries.
To ensure all gloves produced are fit for purpose to satisfy industry standards, glove manufacturers use the process of vulcanisation to provide better performance. Vulcanisation creates cross-links in rubber molecules to enhance properties such as elasticity, tensile strength and tear resistance in rubber gloves (Mok & Eng, 2018). Chemical accelerators have traditionally been used to carry out the vulcanisation process during the production of natural rubber latex, nitrile and neoprene gloves. (Gardner, 2008). Table 1 shows some chemical accelerator compounds commonly used for rubber glove vulcanisation.
Table 1: Commonly used accelerators (Gardner, 2008)
|Tetramethylthiuram Disulphide (TMTD)||Zinc Mercaptobenzothiazole (ZMBT)||Zinc Dibutyldithiocarbamate (ZDBC)|
|Tetramethyl Thiuram Disulphide (TMTM)||Mercaptobenzothiazole (MBT)||Zinc Dimethyldihiocarbamates (ZDMC)|
|Tetraethyl Thiuram Disulfide (TETD)||Benzothiazyl Disulphide (MBTS)||Zinc Diethyldithiocarbamates (ZDEC)|
|Zinc Mercaptobenzimidazole (ZMBI)||Zinc pentamethylene Dithiocarbamate (ZPMC)|
|Zinc Pentamethylene Dithicarbamate (ZPD)|
Beyond the performance benefits of chemical accelerators, there is a growing trend of occupational health risks from the frequent use of gloves containing chemical accelerators. Chemical accelerators, such as carbamates, thiurams, 2-mercaptobenzothiazole (MBT), and 1,3-diphenylguanidine (DPG) in rubber gloves are proven contributing factors to contact allergies (Cao et al. 2010).
Allergic Contact Dermatitis
Allergic contact dermatitis (ACD) is a skin reaction directly linked to the chemical accelerators used in the manufacture of rubber gloves. Studies reveal that approximately 30% of occupationally induced skin diseases are attributed to a chemical allergy (Chen et al. 2004). Similar in appearance to irritant contact dermatitis, the symptoms of ACD become apparent on hands at a point of contact within two days of glove use and include: redness, itchiness, and peeling skin that appears dry and cracked (Al-Otaibi et al. 2015).
Workers in the rubber manufacturing industry who are exposed to chemical accelerators and additives in the development of rubber products are at greater risk of developing cancers. According to Loomis (2018, et.al), types of cancers connected to chemicals and chemical mixtures include tumours of the lymphohaematopoietic system (25%), bladder (20%), lung (15%) and skin (15%). Based on studies conducted by the International Agency for Research on Cancer (2018), the chemical accelerator MBT is probably carcinogenic to humans and has been linked to increased incidence of urinary bladder cancer.
In recent years, glove manufacturers have introduced new production processes resulting in low-protein rubber gloves, vulcanisation accelerator-free gloves and specific purpose gloves (Crepy, 2016). For instance, GloveOn COATS Nitrile has non-detectable levels of accelerators, making it a great alternative for workers with ACD.
To overcome the burden of occupational contact dermatitis, it is crucial for companies to provide education on allergens and skin hazards and offer product substitutes to support their workforce. When tested positive to having a chemical accelerator allergy, the key advice is to avoid contact with the allergen. For most workers who rely on gloves, this is not possible, and their needs must be addressed.
- Al-Otaibi, S.T & Alqahtani, H.A.M 2015, ‘Management of contact dermatitis’, Journal of Dermatology & Dermatologic Surgery, vol. 19, no. 2, pp. 86-91, viewed 21 January 2020, Academic Search Complete database, ScienceDirect, doi: 10.1016/j.jdds.2015.01.001
- Cao, L.Y, Taylor, J.S, Sood, A, Murray, D & Siegel, P.D 2010, ‘Allergic Contact Dermatitis to Synthetic Rubber Gloves: Changing Trends in Patch Test Reactions to Accelerators’, Archives of Dermatology, vol. 146, no. 9, pp. 1001–1007, viewed 23 January 2020, Academic Search Complete database, JAMA Dermatology, doi:10.1001/archdermatol.2010.219
- Chen, H.H, Sun, C.C & Tseng, M.P 2004, ‘Type IV hypersensitivity from rubber chemicals: A 15-year experience in Taiwan’, Dermatology, vol. 208, no. 4, pp. 319-325, viewed 31 January 2020, Academic Search Complete database, Karger, doi: 10.1159/000077840
- Crepy, M 2016, ‘Rubber: new allergens and preventative measures’, European Journal of Dermatology, vol. 26, pp. 525 – 530, viewed 21 January 2020, Academic Search Complete database, SpringerLink, doi:10.1684/ejd.2016.2839
- Gardner, N 2008, ‘Accelerator-Free Fact or Fiction’, Health & Safety International 10 October, viewed 21 January 2020, <https://www.hsimagazine.com/article/accelerator-free-fact-or-fiction-362>
- International Agency for Research on Cancer 2018, Some Industrial Chemicals: IARC monographs on the evaluation of carcinogenic risks to humans, volume 115, IARC, Lyon France, viewed 24 January 2020, <https://monographs.iarc.fr/wp-content/uploads/2018/06/mono115.pdf>
- Loomis, D, Guha, N, Hall, AL & Straif, K 2018, ‘Identifying occupational carcinogens: an update from the IARC Monographs’, Occupational & Environmental Medicine, vol. 75, no.8, pp. 593-603, viewed 31 January 2020, Academic Search Complete database, BMJ, <https://oem.bmj.com/content/75/8/593>
- Mok, K.L & Eng, A.H 2018, ‘Characterisation of Crosslinks in Vulcanised Rubbers: From Simple to Advanced Techniques’, Malaysian Journal of Chemistry, vol. 20, no. 1, pp. 118-127, viewed 24 January 2020, Academic Search Complete database, ResearchGate, <https://www.researchgate.net/publication/327394234_Characterisation_of_crosslinks_in_vulcanised_rubbers_From_simple_to_advanced_techniques>