Dirty diesel

 Dirty Diesel

Have you ever found yourself on a city street coughing or holding your breath as a diesel vehicle pulls away from a set of traffic lights ejecting behind it a bilious exhaust plume, leaving you wondering how that vehicle passed its MOT test? This sort of experience has been on the increase in the UK since Gordon Brown introduced the carbon dioxide (CO2) based company car taxation reform in 2002; diesel powered vehicles have been steadily increasing in number and have become a major portion of traffic on UK roads. Dangerous levels of exhaust pollutants, particularly in urban areas, have accompanied the rise in diesel vehicles. Janez Potocnik, the European Commissioner for Environment, said “Air is essential for our lives, we all have the right to breathe fresh air”, and in the UK we have a fight on our hands to ensure that right.

Air is essential for our lives, we all have the right to breathe fresh air

Prior to the 2002 tax reform on company cars, the tax liability for a company car began at 35% of a car’s list price. This means that the person driving a company car with a new list price of £20,000 would have £700 added to their annual income (for the purposes of tax calculations), and tax paid at the appropriate rate; if in the 40% tax bracket they would pay £280 tax. This tax liability was decreased with increasing mileage with reductions to 25% at greater than 2,500 miles and further cut to 15% if breaking the 18,000 mile barrier. This meant that the company car driver actually paid less tax the further they drove; thus encouraging excessive mileage and larger cars, with the inevitable increase in CO2 emissions.

The UK government, and European Union, were becoming increasingly concerned about the environmental effects of transport, and in 2002 the company car taxation reform was implemented, using the car’s test CO2 emissions to determine a percentage factor of the cars new list price. Lower CO2 emissions meant a lower percentage factor used hence less tax paid, thus making it pay to use/buy more fuel efficient smaller cars with lower CO2 grams per kilometre (g/km) emissions. Diesel cars produce around 10-20% less CO2 than equivalent petrol powered cars, and so the company tax reform heavily favoured diesel cars. A fuel duty tax on company car fuel also favours fuel efficient low CO2 producing diesels. Some diesels with the lowest CO2 emissions are also exempt from congestion charges and road tax. These factors make diesel powered cars an economical prospect for both companies and private individuals.

In 2002 the percentage of licensed diesel cars on the road was 15.2% or 3.9 million cars, by 2014 that had risen to 36.2% or 10.7 million cars

New cars bought by companies are used as a benefit for employees. It makes sense for the companies to buy cars with the minimum tax liability to their employees. The influence of the company car market has been growing over the years: in 2014 company cars were responsible for 54% of all new registrations, in 2002 that figure was 48%. So company cars have a significant and growing influence on the overall UK fleet of cars. The CO2 company car taxation and the high number of cars bought by companies every year has led to the situation we find on the UK roads today. In 2002 the percentage of licensed diesel cars on the road was 15.2% or 3.9 million cars, by 2014 that had risen to 36.2% or 10.7 million cars.

Although diesel vehicles may be considered environmentally friendly in regards to CO2 production, they are far from environmentally friendly when the other pollutants produced are considered. Due to the efficient lean-burning nature of diesel engines and the high pressures and temperatures involved, the exhaust emission contains high amounts of nitrogen dioxides (NOx) and particulate matter (PM) when comparing them to petrol exhaust. A real world example, with data collected from the Vehicle Certification Agency car fuel data website, compares a Ford Fiesta 1.6 Duratorq TDCi Diesel to a Ford Fiesta 1.25 Duratec Petrol.

The diesel powered car produces: 437 g/km of CO2, 150 g/km of NOx and 0.60 g/km of PM

The petrol powered car produces: 519 g/km of CO2, 28 g/km of NOx and *N/A of PM

The figures show that the petrol powered car does produce more CO2, but the levels of NOx are over 5 times lower than in the diesel and the levels of PM were so low in the petrol powered car (N/A = not applicable) that they were below the level of detection of the measuring instrument.

Health risks

Why are the increasing amounts of pollutants a problem? Because there is a growing body of evidence to show that nitrogen dioxides and emission particles are seriously damaging to our health, and not just the obvious respiratory health you might think is being compromised while coughing your way through the traffic fumes. It can also affect your cardiovascular system, with high levels of nitrogen dioxide (NO2), one of the members of the NOx group, and particulate matter causing coronary heart disease (CHD) and heart failure according to a large scale multi country study published in the Lancet. In the UK 73,000 people a year die from CHD, the leading cause of death, and there is an estimated 2.3 million living with the disease. The physiological effects of being exposed to high levels of particulate matter – constricted blood vessels, mild systemic inflammation and increased risk of thrombus (bloodclot) formation – can linger for up to 24 hours after exposure. So if your daily commute takes you into areas of high exposure you may be constantly affected by air pollution.

The big C is also more likely to strike the greater your exposure to air pollution, and in the UK 41,000 people a year are diagnosed with lung cancer. The World Health Authority classified diesel exhaust as a group 1 carcinogen in 2012 after considering all the available scientific evidence. They stated that exposure to diesel exhaust can increase the risk of developing lung cancer and they also noted a possible increased chance of developing bladder cancer. The US Environmental Protection Agency identified diesel exhaust as a possible carcinogen in 2002, and health studies of occupations such as dock, railroad, bus garage and trucking workers have consistently shown a 20-50% increase in the risk of lung cancer.

The World Health Authority classified diesel exhaust as a group 1 carcinogen in 2012 after considering all the available scientific evidence

And now last, but not least, of the scary health section is respiratory illness. This is my favourite because I have a dodgy set of lungs due to coming down with a nasty case of pulmonary tuberculosis in 1998. The damage from TB eventually left me with mild COPD and then I developed asthma in 2011 while hiking in the Cairngorms. In the UK 5.4 million people are currently being treated for asthma. A large study in the Netherlands showed an increase in the development and prevalence of asthma in children (up to 8yrs) that were exposed to higher levels of NO2 and particulate matter. It is ozone that is known to have a particularly bad effect on asthmatics and although no ozone is emitted in diesel exhaust, the NOX (particularly NO and NO2) present react with volatile organic compounds in the atmosphere to produce ozone. When you see smog hovering over a city it is the ozone that gives the smog its brown/orange colour.

Chronic obstructive pulmonary disorder (COPD) causes shortness of breath, coughs, increases respiratory infections and sputum production, and is estimated to effect three million people in the UK. It is caused by narrowing or obstruction of the airways that can occur via a number of different mechanisms. People with COPD are particularly prone to acute exacerbations of the disease when exposed to particulate matter air pollution. A large scale study in Denmark also showed a greater risk of developing COPD when people are exposed to higher levels of traffic related air pollution at their home address.

Electric buses could be part of solution

On January the 13th London bus drivers went on a 24 hour strike; during that time a drastic drop in NO2 levels was recorded. On the day of the strike, on Oxford St, NO2 levels peaked at 205 μg/m3, whereas on the previous 6 days levels had peaked between 316 and 400μg/m3, and levels of particulate matter also showed a similar pattern. Dr David Carslaw, of Kings College London, said of the strike “Because there are so many factors that cause pollution, it can be quite difficult to determine the exact cause… My suspicion is that buses are quite a big cause.” Any future bus strikes in London, or other cities, could help verify how big a contribution buses make to ambient levels of air pollution.

Because there are so many factors that cause pollution, it can be quite difficult to determine the exact cause… My suspicion is that buses are quite a big cause.

The introduction of electric buses to our streets could significantly lower levels of air pollution in urban environments. Trolley buses are a possibility with the buses having to drive under overhead lines. Even the current rechargeable battery technology is well suited to buses, as they travel set distances between specific spots that can easily be adapted to cope with electric vehicles by the installation of charge points. A more convenient option would be to design the buses so that the battery packs can be easily removed (on a trolley) and replaced so that the bus can continue operating while the batteries are being recharged. The BYD ebus is an all electric bus built in China that has a range of 155 miles, on one single charge, under urban driving conditions. The BYD ebus is being widely used in China and BYD have recently opened a production plant in Lancaster, California.

Buses queue in London. Picture Flickr, Sam Lo, DSC_6979-6

Buses queue in London. Photo Flickr, Sam Lo, DSC_6979-6

There is an option for a fully electric bus that does not require ‘long’ charging times and that is the Capabus. This employs onboard large double layer capacitors, that can charge quickly while stopped at bus stops under charging points, which the bus connects to by raising a coupling. The most recent Capabus currently being tested can travel up to 11 km per charge and uses 40% less electricity than an electric trolley bus, due to the Capabus being lightweight and having regenerative braking.

How dirty is UK air?

The UK is often said to have the dirtiest air in Europe, that is not quite true on all counts but we are definitely one of the main contenders for the title. A document produced by Clean Air London showed that in 2010 London, Marylebone Rd scored the 4th (98 μg/m3) highest annual average levels of NO2 when compared to other European cities. When the NO2 annual levels were considered including the years 2006-8, London (109 μg/m3) fared worse, coming second to Stuttgart (111 μg/m3). And when the rest of the UK is considered for zones that have breached EU legal limits (the Limit Value plus a 50% margin of tolerance) The UK is amongst the worst offenders in Europe; when considering the data from 2006-8. The Air Quality in Europe Now website gives an air quality index reading (AQI, calculated from NO2, PM and ozone levels) of air quality in European cities that is updated every hour, The data for the 26th May 2015 shows London at an AQI of 62 meaning on the day it had the fifth highest levels of air pollution after: Berlin, Amsterdam, Paris and Oslo.

Marylebone Road, which the Government claims is the most polluted place in London, appears nowhere in CAL’s ranking of the top 20 worst

There is some debate about how accurate the figures are provided by governments to the EU regarding air pollution. ClientEarth’s Clean Air Handbook states there are inconsistencies between official air quality data and unofficial air quality data on PM; with the official data complying with limits whereas the unofficial data shows breaches of these limits. The Clean Air London website says on this matter “Marylebone Road, which the Government claims is the most polluted place in London, appears nowhere in CAL’s ranking of the top 20 worst”

Pressure to change

In the early 1980s the European Union started to issue directives which limit the amount of air pollutants produced and the ambient concentrations of these air pollutants. The most current of these was issued in 2008 and is named the Air Quality Directive. In the directive are limit values for particular pollutants that are informed by guidelines from the World Health Organisation. There are limit values set for the following pollutants:

  • Particulate Matter (50μg/m3 per hour or mean value of 40μg/m3 per year)*
  • Sulphur Dioxide (SO2)
  • Nitrogen Dioxide (200μg/m3 per hour or mean value of 40μg/m3 per year)*
  • Lead
  • Benzene
  • Carbon Monoxide

*Limit values member states are obliged to adhere to by 2010, with possible extension to 2015

The member states of the EU set up zones where they measure the levels of these pollutants and must publish the results. The member state can be sanctioned by law if the Limit values, in a particular zone, are broken a certain number of times; 18 per year for NO2 and 35 per year for PM.

Why have the UK government not acted to reduce air pollution, were they not aware of the scale of the problem? The government has been well aware of the problem but have been stalling and prevaricating rather than taking measures to address the situation. The nongovernmental organisation Client Earth launched a case against the UK government for failing to adhere to the limit values for air pollution in 16 cities and regions including London, Manchester, Birmingham and Glasgow; they also stated that the government’s own plans showed air pollution would not drop below the required levels till 2020-25. They lost the initial suit but raised an appeal, which was dismissed in 2012.

Another appeal led to a hearing at the Supreme Court in 2013, where the five Judges found in favour of ClientEarth. James Thornton, Chief Exec Of ClientEarth, said of the case “The ruling marks a turning point in the fight for clean air and will pile the pressure on the environment secretary, Owen Paterson. He must now come up with an ambitious plan to protect people from carcinogenic diesel fumes”. Due to the Supreme Court needing to clarify legal issues with the European Court of Justice (ECJ) no order was made against the UK government.

The ruling marks a turning point in the fight for clean air and will pile the pressure on the environment secretary, Owen Paterson. He must now come up with an ambitious plan to protect people from carcinogenic diesel fumes.

In 2014 Janez Potocnic of the European Commission launched legal proceedings against the UK for failing to lower levels of NO2 to comply with the limit values. He added that the UK government had 15 years of warning of the problem and had been awarded a number of postponements and extensions to remedy the problem. These proceedings were made possible by the Supreme Court ruling in the ClientEarth case, and could result in fines of up to £300 million for the UK. In 2015 the Supreme Court (UK) ordered the next environment secretary of the UK government to create a plan, by the end of 2015, to reduce air pollution in accordance with the EU Air Quality Directive.

Why have the UK government not acted to reduce air pollution, is it because it would cost the UK to much? When the fiscal costs to the nation are considered the answer is no. In 2010 the government Environmental Audit Committee published a report based on the findings of the 2007 Air Quality Strategy report. In the report they state that the main cost of air pollution is due to the deleterious effects on health, and that in 2005 the estimated cost of air pollution to the UK economy was between £8.5 and £20.2 billion a year.

However It is not just the cost in money that needs to be considered. What about the missed opportunities that chronic disease often causes, the pain and suffering caused by the increased morbidity of disease in people susceptible to air pollution and the lost years of family members robbed of a loved one too soon? Adding up the figures I used in the health section for annual instances of each disease results in a figure of 10.74 million people that are living with a disease that is either exacerbated or caused by air pollution. That is equal to 17% of the estimate of the UK population in 2014, which is 63.5 million. The estimated number of deaths in the UK caused by air pollution in 2010 was 28,969, according to a report published by Public Health England in 2014. They also calculated the life years lost which when averaged out means 10.6 lost years of life for each person who died due to air pollution. How do you put a price on that?

The estimated number of deaths in the UK caused by air pollution in 2010 was 28,969

What we can do about this problem

I am still a keen cyclist despite my dodgy lungs and it is my preferred form of transport. I recently moved from Dundee (low air pollution) down to Manchester (high air pollution) and was regularly cycling along Oxford Rd/Wilmslow Rd, which I later found out is one of the most polluted roads in Manchester, probably due to the high frequency of buses which service the most densely student populated area in the UK. I experienced more asthma/COPD symptoms after my move to Manchester and had to double the amount of preventer inhaler I take every day to stabilise my breathing. I also had to take 3 courses of antibiotics for chest infections in the first year after moving down to Manchester. I have found that avoiding the most polluted roads by taking alternative routes has helped stabilise my breathing and often leads to a pleasanter ride, if sometimes slightly longer. I advise anyone who is planning a cycling route through urban areas to not use the Google route finding tool, as it generally takes you down the busiest most polluted streets; use a map instead and plan your own routes.

Facemasks can be worn but they can’t filter out nitrogen oxides or ozone and they have to be expensive/well fitting to filter out any particulate matter. So they can possibly reduce exposure to air pollution, but for people with pre-existing health conditions the restriction on breathing may be too much to bear. Avoiding rush hour traffic is also a strategy that can be used to reduce exposure, but is not an option for most commuters. I find it worrying that the government is trying to encourage cycling yet doing next to nothing in providing clean air to cycle in. However the benefits of cycling still outweigh the risks from exposure to air pollution; so start, or keep pedalling.

Be more aware of air pollution by checking the sites and databases that publish information on it. A good source for UK wide alerts is the DEFRA site, which provides a colour coded map that shows predicted air pollution in a simple 1 to 10 index. For London there is a site called ’Clean Air in London’ which did sterling work in forcing the Mayor of London to release government data on air pollution in London, this required several submissions of environmental information requests which national and local government are obliged to respond to. A site called ’London Air’ maintained by Kings College gives a ‘now cast’ which shows current levels of pollution in detail. In Greater Manchester there is a site called GreatAir Manchester, which has monitoring sites in 16 locations across Greater Manchester.

Find out what levels of air pollution are like in your region: if there is no data available on the internet then ask your local authority for their data on air pollution and if they have a plan to reduce air pollution. If they refuse put in a formal environmental information request. If air pollution is a problem in your area then lobby your MP to bring it up in parliament. The government has been resisting pressure to change from outside the country, so maybe it is time we stepped up pressure from inside the country.

What the government needs to do

The most obvious thing the UK government needs to do is to remove the tax incentives to buy diesel cars and use diesel fuel. The company car tax scheme needs to incorporate a factor that makes diesel cars less attractive, while still encouraging low CO2 and zero emission vehicles. Raising the fuel excise duty for diesel, so it is higher than that of petrol, would also decrease the appeal of diesel. These are simple solutions that are easily achievable and should have been implemented years ago.

The uptake of all electric buses by UK bus companies is very poor, there are a growing number of hybrid buses on the road but these are only a partial solution. The government needs to provide carrots and sticks for the bus companies to employ electric vehicles in a timely manner. This could take the form of tax breaks for buying electric vehicles. Grants could be offered to fund the infrastructure upgrades needed. Gradually reducing the Bus Service Operators Grant, which allows bus companies to recover 61% of the duty paid on diesel fuel, would also encourage electric bus uptake. Making busy shopping streets pedestrian only would help, as would the speedy introduction of low-emission zones, with sufficient enforcement of such zones, in cities other than London.

Capabus recharging at bus stop. Photo By Brücke-Osteuropa (Own work) [Public domain], via Wikimedia Commons

Capabus recharging at bus stop. Photo By Brücke-Osteuropa (Own work) [Public domain], via Wikimedia Commons

Why have the UK government not acted to reduce air pollution, is it because the UK government is influenced by vested interests involved in the production and selling of diesel? In my opinion the answer is yes, it is the only answer that makes any sense. The UK is home to two of the biggest Oil companies in the world British Petroleum and Royal Dutch Shell, both of which are incorporated in the UK. A recent news article in the Guardian details how uncomfortably close the bosses of BP are with the cabinet, and how big an influence they are on government policy. It is likely that Shell has a similar influence on government strategy. This creates a problem as both BP and Shell are pouring funds into finding and extracting oil from previously unknown or unreachable oil reserves, whereas the government has the stated aim of reducing carbon emissions. The government therefore needs to distance itself from vested interests when considering its strategy on environmental issues.

David Cameron is currently doing a tour of European countries, trying to gather support for the renegotiation of the UKs terms of European membership. It would not surprise me if he is also trying to wriggle out of the UKs obligations on air pollution during his European tour. In the coming referendum on our membership of the EU, if you think environmental issues are a primary concern, then you must vote to stay in the EU. Membership of the European Union will enable the United Kingdom to achieve clean air standards, protect our environment and ensure our right to breathe fresh air.

First Published in the June 2015 edition of Contributoria.

Conrad Bower

Cycling Scientist Blog – https://conradbower.wordpress.com
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Twitter –  @ConradBower1
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