Air Pollution In Bristol: Our Retort

October 13, 2017 • Chuck News, Featured, UK • Views: 195

Earlier this month we published an article here at Chucktown. In which we debated the effectiveness of the Rising Up Bristol rally that took place at the top of Park Street a couple of Wednesday’s ago.

When we shared this through our social media accounts, certain groups including the Bristol WNBR disagreed with our claims. WNBR particularly zoned in on our response to a protester’s claims that air pollution kills 300 Bristolian’s per year.

My response was as follows.

“the figure of 300 Stu quoted, is most likely utter bullshit.”

The article came to the determination that in fact it was around 1-2 people were killed directly by pollution. You can see the original article here.

The Right Way To Go?

[Credit: Anita Hummel]

Rising Up decided the best way to protest the need to control pollution, was to cause more pollution by blocking traffic. I asked for a statement on this and they happily obliged.

“In terms of why we chose the road block protest. We believe that it highlights how many cars there are travelling through the city at the moment and the damage that is having on our health. A 10 minute road block makes a tiny difference to the amount of air pollution caused in the city compared to the thousands of motorists that travel through it every day. The Stop Killing Bristolian’s campaign aim is to raise awareness of how dangerous air pollution is to the Bristolian’s that have to walk through it everyday. Particularly in vulnerable areas such as around primary schools.”

The statement continued.

“In order to get to the council to hasten its existing Clean Air plans, we believe that direct action will bring the issue forward to the public,  raise awareness of the situation and force the councils hand through a series of demands that will reduce air pollution. Thereby improving Bristolian’s health, saving lives and protecting our most vulnerable citizens.”

As you can gather from this statement, the group want to highlight how the people of Bristol can cut down emissions through controllable pollution use. In doing so, it would save 300 lives a year. Rising Up didn’t appear to read further down the report.

Thinking back to the original statement, “around 300 deaths each year in the City of Bristol can be attributed to exposure to both nitrogen dioxide and fine particulate matter”. The use of the word “can” and not the word “are”, concerned me.

The results are majorly different from both perspectives.

Differing Results


The information Chucktown used was gathered from the Director Of Public Health Annual Report for 2016 . This was used to debunk the theory that 300 people die a year in Bristol from pollution. Thankfully, I was directed to the report that Stu had used for his claim, provided by Bristol WNBR to prove me wrong. 

The report was written by Air Quality Consultants Ltd on behalf of the Bristol City Council. In the Executive Summary it does indeed allude to 300 deaths being attributed to air pollution.

“The new results show that around 300 deaths each year in the City of Bristol can be attributed to exposure to both nitrogen dioxide and fine particulate matter,” the Report said. 

Unfortunately this statement, although bold, doesn’t explain how they came to this conclusion.

Intrigued by this new information I had to ask myself how I could be so wrong? The Public Health Report shows completely different results. Myself and Chucktown Editor Ryan Child decided to look through the report. It was important to find out why there was such disparity in our results. 

Breaking It Down Mathematically


The deaths are attributed to a combination of both Nitrogen Oxide and Particulate Matter. In simple terms this means that they are both responsible for 50% of deaths. Therefore, half the deaths have to be attributed to each Nitrogen Oxide and Particulate Matter when deciphering the results.

Particulate Matter according to the report, comes from both natural and anthropogenic sources. Anthropogenic sources can only both be primary and secondary all coming from places such as power plants, road vehicles, domestic heating and shipping.

While investigating this Particulate Matter, the report found:

“27% of the anthropogenic fraction being effectively from local sources, which can be considered to be potentially locally controllable”

It should be noted that just under half of these controllable sources are from traffic congestion.

Next we have to separate and look at Nitrogen Dioxide, which is determined by emissions usually from combustion processes. The main sources of Nitrogen Dioxide pollution are road transport and the electricity supply industry. The report states that Road Traffic is the main cause of this pollution.

Continuing on from that point, the report states:

“around 74% (Nitrogen Dioxide emissions) are effectively from local sources, which can be considered to be potentially locally controllable. Over half (59%) of this locally controllable nitrogen dioxide is associated with local road traffic.”

Looking at the figures in-depth, that means that if we can only quantify that these pollutants combined cause these deaths, then they are both equally responsible.

Therefore at 27% of Particulate Matter being controllable pollution. Then controllable deaths are at 40 per year.

Nitrogen Dioxide on the other hand is 74% controllable pollution. Therefore is responsible for 111 deaths per year.

Inconsistent Findings


In total, controllable emissions cause 151 deaths per year. Not the 300 being used to cause an emotive response. How can the uncontrollable be controlled? Simply put, it can’t. Protesting the uncontrollable is like protesting a Tsunami. 

It should be mentioned that the report appears to have some glaring issues. Firstly, the use of the word “potentially” in front of word controllable. That means we are not getting direct figures on what is actually controllable, only an estimate. Secondly and more importantly it is admitted in the report the company are still not 100% on how to quantify the damage caused by Nitrogen Oxide.

“COMEAP has been, and still is, reviewing the evidence to provide its best advice on quantifying the number of deaths attributable to nitrogen dioxide. It has produced an interim advice note on this quantification and also how to combine the deaths attributable to particulate matter with those due to nitrogen dioxide (COMEAP, 2015).”

The report also claims that there are more deaths that “can” be attributable to air pollution. This is because the report is done on national averages and not Bristol specifically. The report has a lot of convoluted equations to come to the conclusion of 300 deaths per year.

Two Wrongs Don’t Make A Right


I am more than ok with admitting that I was wrong when I used just the Public Health Report to back up my previous article. It is clear now that my figure was way off. That being said, unfortunately it means that Rise Up’s claims were also incorrect. Protesters need to be clear and accurate when making statements. Using emotive points will help, but only if it is correct.

Overall the Air Quality Consultants Ltd report has too many ‘potential’ figures and not enough specific figures. The report itself is confusing, convoluted and not intended for the general public to read.

Another interesting point to be made is the Air Quality Consultants have a vested interest in reporting the figures are worse. They are not just a company that provides the data for Air Pollution effects, but they are also an Air Pollution management company. If their report suggests action is needed, let’s face it, they’re a shoe in for the job.

A Solution For All


After reviewing, clearly there is an issue with pollution. However it is not as awful as previously thought, in fact 50% less awful than we have been told. I still maintain the position that there would be better ways to protest other than stopping traffic, which causes more pollution. The solution also doesn’t seem to be down to just traffic. Only 13.5% of Particulate Matter and 59% of Nitrogen Dioxide emissions are from traffic. There are clearly a lot of other contributing factors.

The need for a cycling city isn’t exactly fair either. What about disabled people? Or the people who have to drop their kids to school each morning and then straight to work? The argument from Rising Up is very one-sided. Modern life isn’t as simple as just leaving the car at home. It could be argued that pollution around Bristol has worsened since the council pedestrianised a lot of the city centre.

However maybe Bristol could follow Oxford City’s lead? Oxford today announced plans to make the city completely diesel and petrol car free by 2035. I personally feel this is a fantastic initiative and would like other cities to adopt this. We no longer need diesel or petrol cars, due to the fantastic progress made in the last 20 years with electric and hydrogen based fuels.

Overall. I was wrong. Rising Up were wrong. The answer is somewhere in the middle. Unfortunately the actual figure is still not known. The report doesn’t satisfy the need for fact. That said, let’s find solutions that don’t cause more traffic pollution. People travelling around the city need different choices, and not just cycling. Oxford City Council appear to have got it right and maybe Bristol should follow suit. 

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