Aston involved in Mission for Health campaign

Swab analysis
Swab analysis

17 May 2011

Dettol's Mission for Health campaign investigates the cleanliness of where we live, work and travel.

Seats are host to more bacteria than any other part of public transport carriages. On average, seats are host to over 48,000 bacteria per cm2. That is 164 times more bacteria than the buttons (used to open/close doors and alert the driver), 127 times more than a hand rail and 30 times more than a grab rail or pole.

This research was carried out by Dettol as part of their Mission for Health campaign that involved bacteria swab analysis on six UK transport systems and a consumer survey online to understand how people feel about the health of their local areas.

Earlier this year Microbiologists from the School of Life & Health Sciences took swabs from the most popular routes of the main transport systems in Birmingham (light rail), Cardiff (bus), Glasgow (subway), London (Underground), Manchester (tram) and Newcastle (metro). Within each transport type a carriage from the busiest route was selected and, in one session, a number of surfaces were swabbed, such as the seats, handrails and buttons. From the swabs cultures were grown in a lab to identify the number of colony forming units per square centimetre as a measure of viable bacteria present.

Comparing the results across the cities, Newcastle’s Metro light rail system was found to carry the most bacteria, with an average 48,000 bacterial cells per cm2. Manchester’s trams were found to be the ‘cleanest’ with a bacteria count of 213 per cm2. To compare then, Newcastle’s trains have 227 times more bacteria than a Manchester tram.

Average bacteria counts per cm2 for UK transport systems:

  • Manchester: 213 per cm2
  • Birmingham: 295 per cm2
  • Glasgow: 535 per cm2
  • London: 677 per cm2
  • Cardiff: 2285 per cm2
  • Newcastle: 48,219 per cm2

Newcastle’s metro had the highest average bacteria count, this was largely due to the extremely high number of bacteria found on their seats, a count of 190,500 per cm2. This was the highest figure for any of the areas tested across all of the transport types swabbed. However, tests for bacteria on poles show that, for these areas specifically, then Cardiff buses have the dirtiest with a count of 3,850 bacteria per cm2. Buttons, those used to open and close doors and alert drivers of upcoming stops, were found to be the cleanest spots on all of the transport types tested.

The London underground, the most densely used transport in the country, was found not to be the dirtiest. Here seats showed a bacteria count of 1,395 per cm2; some 137 times lower than the seats on Newcastle’s metro trains.

Top ten dirtiest part of transport systems across the UK

  1. Newcastle Metro seat: 190,500 bacterial cells per cm2
  2. Cardiff bus seat: 4,600 bacterial cells per cm2
  3. Cardiff bus pole: 3,850 bacterial cells per cm2
  4. London Underground seat: 1,390 bacrerial cells per cm2
  5. Newcastle Metro pole: 1,390 bacterial cells per cm2
  6. Glasgow Subway seat: 1,000 bacterial cells per cm2
  7. Manchester Tram seat: 705 bacterial cells per cm2
  8. London Underground pole: 535 bacterial cells per cm2
  9. Newcastle Metro handrail: 480 bacterial cells per cm2
  10. Birmingham Light Rail seat: 425 bacterial cells per cm2

These transport bacteria tests were run alongside a Dettol Mission for Health consumer survey. Over 6000 people were surveyed in Birmingham, Cardiff, Glasgow, London, Manchester and Newcastle (the same towns that were used in the transport analysis) to discover attitudes towards the health and cleanliness of their local area.

Results revealed included that the majority, 62%, of people in the UK are concerned about coming into contact with bacteria and bugs when out and about. Men less so than women, 63% versus 67% respectively.

Dettol’s Mission for Health aims to support and educate on how to best maintain a happy and healthy environment and is committing to this with a £5,000 spend on a health-over for a nominated public area. Terms and conditions apply including local council approval.

For more information, the transport swab analysis and consumer survey results in full or interview requests contact  CJ Brough by emailing cj.brough@multiplyuk.com