Posted By Chris Packham
In response to the previous posting:
1. Re barrier creams:- I quote from HSE’s publication: “Assessing and managing risks at work from skin exposure to chemical agents”, U.K.Health and Safety Executive, 2001, ISBN 0-7176-1826-9” – ““Pre-work creams cannot be relied upon for primary protection of the skin as there is no information on the rate of penetration of chemicals through creams. Also, people habitually miss areas of their exposed skin when applying creams and so complete skin cover cannot be guaranteed. It is not always obvious if the barrier has been removed, damaged or thinned.”
In the words of a leading dermatologist: “It is now generally accepted by the medical and legal professions that barrier creams have no protective function on the skin, and recent evidence would suggest that they may indeed facilitate penetration of the skin by irritants. Occasionally, dermatitis has even developed to the barrier cream itself.”(Prof. Burrows in Essentials of Industrial Dermatology). At a dermatology conference last year two papers were presented showing increased absorption of chemicals into the skin where a barrier cream had been applied compared with untreated skin.
I have a review of the evidence on these creams in the form of a Technical Bulletin. Normally we charge for this but I view of this thread I am prepared to e-mail it to anyone who contacts me direct.
2. Re gloves – I would never recommend natural rubber latex gloves for use with hydrocarbons. The glove may appear to be protecting but in reality the chemical may be migrating through the glove at a molecular level and emerging as a vapour on the inside. Whilst engine oil will take time to do this, some of the consituents in used engine oil may partition out and permeate very quickly. Note that I have no objection to natural rubber latex as such provided that any glove is of low free protein and unpowdered.
The selection of gloves for chemical protection is a complex topic. In “Protective Gloves for Occupational Use” (edited by Boman, Estlander, Wahlberg and Maibach, CRC Press, ISBN 0-8493-1558-1) this is dealt with in chapter 18 which runs to some 30 pages and still, in my view, leaves a great deal out (and I co-authored this chapter!).
3. Re cotton gloves – There is abundant evidence that wearing of occlusive gloves for an extended period can lead to irritant contact dermatitis due to the hyperhydration of the skin inside the gloves. This has been termed “hydration dermatitis” by Prof. Kligman in the USA. It is also covered in TRGS401 in Germany, where wearing of occlusive gloves is considered equivalent to wet work and, if the gloves have to be worn for more than 4 hours in total in an 8 hour shift special precautions have to be taken. Not only can dermatitis appear due to the occlusion, but the effect is that the skin’s barrier properties are impaired and any contamination inside the glove can cause increased damage (Effect of glove occlusion on human skin - Long-term experimental exposure, Ramsing DW, Agner T, Contact Dermatitis 1996, 34, 258-262) and (Rawson BV, Cocker et al.: “Internal Contamination of Gloves: Routes and Consequences”, Annals of Occupational Hygiene, 49, 6, 535-541, 2005). The study by Ramsing and Agner also showed how the use of cotton gloves underneath the occlusive glove significantly reduces the hyperhydration and hence the risk of dermatitis.
Provided that category III nitrile gloves (which will still provide adequate dexterity) are used, in the many years that I have been involved in the prevention of damage to health from skin exposure I have not found a problems such as those mentioned (although it will be a problem with the extremely thin category I gloves).
Chris