2023-08-10 10:52

ULEZ is a LIE !

Why ? because the understanding of inner city air pollution is all wrong !

Air pollution is of great public concern but the big reasons for it are NOT what you think – and they have gone entirely unreported – because much of that air pollution is actually brought about by the technologies meant to reduce air pollution = Catalytic Converters (CATS) on petrol & diesel cars, buses, vans and lean-burn engines -

Unbelievable – but true !    So read on – if you dare !

The environment, air quality & catalytic converters (exhaust emission control devices) [CATS]

Much has been made of the poor air quality in our towns, cities & around the world and in particular as regards vehicular pollution within inner cities.

To reduce such pollution, in around 1975 in USA and later in the UK – between 1990-2001- were introduced mandatory catalytic converters (CATS) on all new petrol & diesel vehicles.

These CATS are platinum, palladium and rhodium catalysts inside every exhaust system on every road vehicle. These catalysts – CATS - were heralded as opening up a new dawn of clean air in our cities – burning off unburnt fuel, carbon dust & other particulates like PM10 and PM2.5  oil and carbon monoxide – turning them into nothing more harmful than CO2 and water –  IF ONLY !!

In reality, largely because of these CATS, the air quality in our towns & cities continues to decline dramatically – for example – in this govt document -

Air pollution: applying All Our Health - GOV.UK

“The annual mortality of human-made air pollution in the UK is roughly equivalent to between 28,000 and 36,000 deaths every year.  28 Feb 2022”


“It is estimated that between 2017 and 2025 the total cost to the NHS and social care system of air pollutants……..

(fine particulate matter and nitrogen dioxide, for which there is more robust evidence…..),  will be £1.6 billion”.


[ pls note – this document shows that the UK government is aware of the problem of nitrogen oxides - NOx on our streets, but for reasons best known to themselves, continually emphasise the role of particulates only – to the detriment of a wider understanding of the problem ].

Not since the ban on the use of coal by the UK clean air acts has air pollution been so bad. The London pea-soupers and black smuts may have gone, but there is still more air pollution in our towns & cities – and it is Deadly !

This pollution has been blamed on simple increases in vehicular traffic – but there is a much more obvious reason which is being overlooked – and is essentially “unknown” to the public – which is

 = the mandatory use of Catalytic Converters.

Nobody seems to have “joined the dots” but what we do know is that the adoption of CATS – leading to higher NOx - is seriously bad for air quality and our health – leading to increased pollution, illness and death on an huge scale due to the formation of acidic oxide gases of sulphur & nitrogen.

Typical of the problem was the recently publicised asthmatic death of a little girl in London in 2013 -

   “A coroner has called for a change in the law after air pollution led to the death of a nine-year-old girl. 

   Ella Adoo-Kissi-Debrah, who lived near the South Circular Road in Lewisham, south-east London, died in 2013.

An inquest had found air pollution "made a material contribution" to her death. 21 Apr 2021”.


But the problem with this conclusion is that the coroner in this case - blaming the death on microparticulates –

“Coroner Phillip Barlow said there is "no safe level of particulate matter" in the air and called for national pollution limits to be reduced” –

     - in fact overlooked the most obvious culprit – acidic oxides of nitrogen and sulphur – the asthma-inducing gases, nitric & nitrous acids & sulphuric & sulphurous acids - which are actually increased by these catalysts.

(Microparticulates have complex chemistry and can include microdroplets of these gaseous oxides themselves, as well as carbon & other dusts – but this nomenclature – the grouping together of dry dusts with acidic microdroplets as “microparticles” – misses the point - that the internal combustion engines AND the CATS are both producing acidic oxide gases which can cause asthma & death and the combination of modern lean-burn engines with CATs is the worst possible combination ).

In a genuine bid to improve air quality, the scientific advice was unfortunately incomplete and instead an already serious problem has been made very much worse.

      The Chemistry

the main aim of Catalysts was to use the residual heat from the engine to burn the waste hydrocarbons and carbon monoxide from incomplete combustion at very high temperatures - producing just water and CO2.

This works very well indeed, UNDER IDEALISED CONDITIONS – LIKE, FOR EXAMPLE, AN MOT TEST - but this same high temperature is ideal for producing oxides of sulphur & nitrogen – forming sulphur dioxide & trioxide (making sulphuric & sulphurous acid vapour) and nitric oxide and nitrogen dioxide

(making nitrous & nitric acid vapour). These acidic vapours & mists are extremely corrosive & irritating to the lungs & airways but incredibly so to sensitive individuals, like asthmatics or those suffering allergies and sensitivities.

Sulphur is a tiny component of petrol & diesel fuel and the nitrogen is from the atmosphere – but this reaction is made much worse by the common use now of lean-burn engines – which have better fuel economy, but which burn at a much higher temperature  – creating even more of the acidic NOx – nitrogen oxides.

The WHO stance also seems to inexplicably omit the role of these acids whilst discussing only the microparticulates in any depth and – whilst they are indeed very harmful – microparticulates are only a part of the overall air pollution picture and tend to produce illness over a very much longer timescale –  months or years, whereas the acidic oxide gases could result in death within minutes - because a person who cannot breathe cannot survive long  – and asthmatics are particularly susceptible to this effect.

For instance -  https://www.who.int/news/item/12-05-2016-air-pollution-levels-rising-in-many-of-the-world-s-poorest-cities

WHO was able to compare a total of 795 cities in 67 countries for levels of small and fine particulate matter (PM10 and PM2.5) during the five-year period, 2008-2013. PM10 and PM2.5 include pollutants such as sulfate, nitrates and black carbon, which penetrate deep into the lungs and into the cardiovascular system, posing the greatest risks to human health”.

The adoption of CATS has been universal, is mandated through UK, European & other first world legislation & this is one big reason why new inner city pollution is generally getting worse rather than better – especially ironic since the ban on domestic sulphur-laden coal-powered heating. You may have noticed, in city streets by the traffic, a bleach-like odour – which is the NOx – nitrogen oxides/nitric acid or a suffocating wheezy atmosphere which makes you catch your breath – the sulphur oxides. Other compounds, like carbon disulphide and hydrogen sulphide (bad egg smell) can also be produced by CATs under differing oxidation states, and you’ll have doubtless noticed these smells also.

There is an abundance of information about the effects of these gases on breathing – for example -

“Sulfur dioxide affects the respiratory system, particularly lung function, and can irritate the eyes. Sulfur dioxide irritates the respiratory tract and increases the risk of tract infections. It causes coughing, mucus secretion and aggravates conditions such as asthma and chronic bronchitis.27 Mar 2017


and (same document) – NOx - “Elevated levels of nitrogen dioxide can cause damage to the human respiratory tract and increase a person's vulnerability to, and the severity of, respiratory infections and asthma.

Long-term exposure to high levels of nitrogen dioxide can cause chronic lung disease”.

The answer is simple –

To ban catalytic converters immediately & remove those already in use – the use of CATs is almost totally counter-productive & these pollutants cause many many deaths annually – there ARE devices – normally used on PSV – public service vehicles, like buses, to mitigate the output of acidic gases, but these are very rarely (never) used on private vehicles.

The wider adoption of electric vehicles and the ban on sales of new petrol/diesel vehicles from 2030 in the UK will have the added benefit of massively improving urban air quality, but petrol/diesel/hybrid vehicles will likely still be around for many years to come. There exists plenty of data to support the above, but it seems that, whether intentional or not, nobody in government or the scientific community at large has “joined the dots” in this matter and some specialist industries would suffer if the use of CATs was stopped, but the alternative is many more avoidable deaths – thousands of deaths LIKE THAT OF ELLA - every year.




1.    -  inner city streets – wear an anti-smog mask.

2.    – indoors – if you can, avoid cooking on gas – which also produces NOx    emissions – and indoors too !

3.    – at home – avoid anything that emits polluting VOCs & solvents – including formaldehyde (new MDF, new radiators, carpets, new fabrics) – and avoid standard VOC-based paint & varnish – even LOW VOC paint contains literally Thousands of Times more than Lakeland Paints – which is independently certified as Zero VOC !

4.    – reduce your air fresheners, aerosols, perfumes, scented candles etc.

5.    – talk to your MP, your friends & relatives about ULEZ, inner city pollution, Catalytic Converters and the use of Lean Burn engines.