Prion risk: where do we draw the line?
Millions of nail clippers are incinerated every year across the NHS, as a result of policies to manage the theoretical risk of vCJD, according to an article by Julie Hotchkiss, public health consultant in Wigan.(1)
In her article, "The nipper mountain: Impact of policy to manage theoretical vCJD risk costs dear to the environment", Julie describes how, in the 1990s, the occurrence of Bovine Spongiform Encephalopathy (BSE) in cattle and of new-variant Creutzfeldt-Jakob disease (CJD) in humans were traced to a single infectious agent - an abnormal prion protein. When the possibility of accidental transmission of prions through surgical procedures was raised, a precautionary approach was taken: the standards for sterilisation of surgical instruments were increased, to the point where many hospitals and GP practices opt for single use items rather than investing in new equipment and training.
The total realised risk of contracting CJD through healthcare for the last 20 years is quoted at about 1 in 10,000,000, with the existing sterilisation procedures to 2002.
What about the health risks from wholesale transition to single use equipment? There are direct risks: the Department of Health directive for single-use surgical instruments for tonsillectomy in 2000 was suspended after a few months months because of patient deaths from post-operative bleeding - blamed on poor quality instruments.
But are there not also some indirect health risks, from the environmental consequences of large scale production and disposal of single use items? After all, the NHS carbon footprint shows that provision of pharmaceuticals and medical supplies accounts for greater carbon emissions than energy use across the whole NHS.(2) And the Lancet report earlier this year identified climate change as the greatest threat to global health in the 21st century.(3) They may be more difficult to quantify, but the carbon emissions associated with manufacture, packaging, transport and incineration of these items, as well as other environmental impacts such as pollution - these are not theoretical but real impacts. And if the switch to single use items is contributing to climate change, then it is already contributing to deaths worldwide from malnutrition, diarrhoea and infectious disease - today.
Julie Hotckhkiss is not the only health professional to question the risk-benefit profile of disposable items. Dr John Somner's article on disposable eye drops (4) reminds us that Mount Nipper is just one in an extensive mountain range. Neighbouring peaks include the razor-edged Scissor Mountain, the craggy Mount of Surgical Instruments, the mighty Mountain of Dialysis Products, the Mounds of Surgical Gowns and Drapes, Nappy Mountain - and many more.
- Hotchkiss J. The nipper mountain: Impact of policy to manage theoretical risk costs dear to the environment. http://www.sustainabilityforhealth.org/clinicaltransformation/reports/1465
- NHS (2008) ‘NHS England Carbon Emissions: Carbon Footprinting Report 2008’ available at http://www.sdu.nhs.uk/page.php?page_id=93
- Costello A et al. Managing the health effects of climate change: Lancet and University College London Institute for Global Health Commission. Lancet. 2009 May 16;373(9676):1693-733.
- Somner JE, Cavanagh DJ, Wong KK, Whitelaw M, Thomson T, Mansfield D. The precautionary principle: what is the risk of reusing disposable drops in routine ophthalmology consultations and what are the costs of reducing this risk to zero? Eye. 2009 Jun 12. [Epub ahead of print]. http://www.sustainabilityforhealth.org/eliminatingwaste/reports/1367
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