Most of our laws in the UK relating to public health, occupational health and the environment are based on EU Directives. The European Commission can take enforcement action when governments fail to comply. 

The EU commission started 753 actions against the British Government between 2003 and 2016, of which 120 related to the environment, according to the Institute of Government. That equates to nine environmental actions every year. Most were settled, but 29 cases reached the European Court of Justice.

The UK government has published a Draft Environment Bill which requires Ministers to “have regard” for a set of environmental principles when formulating government policy, in order to compensate for the loss of EU scrutiny post-Brexit.

Green watchdog

The Environment Bill further proposes to establish a green watchdog called the Office for Environmental Protection (OEP) which will monitor performance and if necessary initiate enforcement measures against public authorities if the breach of environmental principles is considered sufficiently serious.

The remit of the OEP includes clean air, so an obvious question is whether the OEP will hold the UK Government to account for breaching air quality standards once we leave the EU.

Air quality standards for nitrogen dioxide (NO2) and small particulates (PM2.5) are already enshrined in UK law, and the failure of the UK Government to comply with NO2 standards has already led to a series of defeats in the High Court.

Theoretically, the OEP could take action provided that Ministers don’t tamper with existing legislation, and assuming that the OEP is established as a truly independent body.

This sadly seems doubtful, as a majority of members on the OEP will be appointed by the Secretary of State for the Environment. It stretches credulity to think that the Government would now establish a statutory body to enforce legislation that the Government has been actively resisting for the past eight years.

Legal standards

There is however a bigger problem. Court action has focused on NO2, which is particularly dangerous for asthmatics. But the medical effects of PM 2.5 are even more serious and wide-ranging and account for most of the 40,000 deaths that occur annually in the UK from air pollution.

The annual EU air quality standard for PM2.5 is 25 microgrammes per cubic metre of air, but the medical effects of PM2.5 are without threshold. In the US the legal limit is 12, and WHO have recommended a guideline of 10. Average levels in Central London are around 15. So what will the OEP do post-Brexit?

Currently the EU Commission are reviewing The Ambient Air Quality Directive, and will doubtless recommend stricter legal standards.

Known effects of PM2.5 in adults include heart disease, stroke, chronic lung disease and cancer. In children the best-documented effects are on the respiratory system and include physical effects such as reduced lung volume, but there is also serious concern about the unborn child.

It is well known that smoking in pregnancy reduces birth-weight, and the same is true of air pollution. Again it is PM2.5 that shows the strongest correlation.

Toxic exposure

It is also known that smoking and air pollution is associated with reduced IQ in childhood.

Researchers in the US studied a group of non-smoking pregnant women in New York and showed that higher exposure to a subset of small particulates, Polycyclic Aromatic Hydrocarbons (PAHs) was associated with developmental delay at 3 years, a reduction in IQ of 4-5 points at 5 years, increased anxiety and depression at 7 years and a lack of self-regulatory behaviour that became more significant over timewhen followed up for 11 years.

A recent study based in London demonstrated that 12 year olds exposed to higher levels of air pollution had a four-fold risk of depression at age 18.

These are very worrying observations. Even so, the studies are preliminary and do not allow firm conclusions as to the most dangerous toxin or the most critical period of exposure.

Most traffic-derived PAHs come from diesel vehicles, and reach the maternal circulation both as gases and particulates.  The only PAH measured routinely in Europe is Benzo-a-pyrene (BaP).

From a mental health perspective, it may well be significant that BaP levels at traffic monitoring sites in the EU have increased by 52 percent since 2000, due largely to the growth in sales of diesel vehicles. In the UK diesel cars have increased from less than 14 percent of new registrations in 2000 to almost 50 percent by 2015.

Remedial action

It is likely that the EU Commission will impose stricter standards for both PM2.5 and BaP, and pressure will grow for a more rapid phase-out of diesel vehicles.

However these new standards won’t benefit UK citizens. The government’s recent Clean Air Strategy does include a commitment to halve the number of people in the UK exposed to levels above the WHO limit for PM2.5 by 2030, but this is not a standard. This is an aspiration that lacks any legal force.

Before Christmas DEFRA Minister Therese Coffey expressed the view that not all the associations between air pollution and health are causal. Even so, the precautionary principle holds that remedial action should be taken even when medical or scientific concern is less than certain.

The OEP could and should therefore challenge government policy and force the introduction of stricter air quality standardson the basis of the environmental principles set out in the Draft Environment Bill.

However, page 12 of the Bill’s wxplanatory notes states: “The  precautionary principles should be considered where there are reasonable grounds for concern … taking into account the available scientific evidence, and the associated costs and benefits of action and non-action”. This is a very weak interpretation.

Precautionary principle 

A stricter definition would require the polluter to demonstrate that a particular activity did not have an adverse effect.

Second it indicates that the precautionary principle is nothing more than a trade-off wherefinancial costs to the motor industry can be cited by the responsible minister as an excuse for inaction.

Finally the environmental principles contained in the Draft Bill includes outdoor, but not indoor air pollution, which makes it difficult for the OEP to fulfil its stated function in relation to clean air.

If people are expecting a watchdog with teeth, then don’t hold your breath.

This Author 

Dr Robin Russell-Jones is former Chair of CLEAR, the Campaign for Lead Free Air.