BY MARILIS AZZOPARDI

In Gibraltar, there are no significant measures or strategies in place to tackle what has been called a “public health crisis”, and an air quality action plan that had been implemented by the previous government has long been abandoned.

We are exposed to a large number and wide range of pollutants due to the proximity of many petrochemical industries, but the major measured pollutants are nitrogen dioxide and particulates (PM) created during the combustion of fossil fuels. Gibraltar has failed to achieve compliance with EU annual mean limits for nitrogen dioxide since monitoring began and consistently fails to achieve the World Health Organisation’s limit guidelines for particulate matter.

Road traffic is one of the biggest sources of nitrogen dioxide due to the use of diesel, which leads to more NOx emissions when compared with petrol. The use of diesel for cars was heavily promoted in the early 2000s as a solution to climate change, with claims that it provided better mileage per gallon and produced ten percent less CO2 than petrol cars. However, the drawback was that it led to higher emissions of nitrogen oxides and harmful fine particulate matter. We now know that these ultra-fine diesel particles are associated with heart attacks, strokes and cardiovascular problems.

Gibraltar consistently fails to achieve the World Health Organisation’s limit guidelines

Traffic emissions also contain large quantities of carbon monoxide, hydrocarbons and toxic compounds such as benzene, acetaldehyde, formaldehyde,1,3-butadiene and lead. Secondary pollutants such as volatile organic compounds (VOCS), ozone and nitrates also form when the pollutants undergo reactions with sunlight or other aerosols in the air, sometimes a distance away from the original source.

A significant proportion of the nitrogen dioxide measured in Gibraltar also comes from the combustion of diesel fuel used in the old power stations, the many temporary generators used for power generation and shipping emissions from vessels passing through and refuelling in the bay. It is not uncommon for levels of the pollutant to be higher at night despite road traffic being very low. Nitrogen dioxide is twice as dense as air and takes around 200 to 500m to disperse, with some studies finding it takes up to 1500m. Thus, due to Gibraltar’s small size the gas is not so easily dispersed and accumulates; something that becomes dangerous when there’s little wind and periods of inversions.

WHO IS MOST AT RISK?

Pollution affects an individual at every stage of their life from the womb to old age. Children are more susceptible to the harmful effects of pollution and exposure can lead to problems with physical and mental development. A London study found that exposure to even low amounts of nitrogen dioxide leads to slower or stunted lung growth in children. These effects may cause them to develop lung disorders at an earlier age and suffer more disability and ill-health as a result. Children living in polluted areas suffer more wheezing and coughs, respiratory infections as well as a higher risk of allergic conditions and asthma. Infants breathe in three times the amount of air when compared with an adult, and an active six-year old six times as much relative to their body weight, so when air is polluted, their lungs are processing and filtering more air.

Infants breathe in three times the amount of air when compared with an adult

In adults, air pollution is also linked to asthma and respiratory disorders such as chronic obstructive pulmonary disease and bronchitis. Living near a busy road accelerates the decline in lung function that comes with ageing and also increases the risk of suffering a heart attack. The link with cardiovascular disease is well established with air pollution both causing and exacerbating existing heart disease. The main driver for the process is oxidative stress and inflammation that damage and constrict the walls of arteries leading to high blood pressure, increased stickiness of the blood, increased risk of arrhythmias and risk of plaque accumulations rupture; all of which can lead to kidney damage, heart attacks and strokes. This makes the elderly and those with existing heart conditions a particularly susceptible group. Some people are also more vulnerable to the effects of different pollutants due to genetic variation in the enzymes that detoxify environmental pollutants.

ARE THERE SAFE LIMITS OF POLLUTION?

On my Facebook Page, Pollution Watch Gibraltar, I often draw attention to EU health limits or guidelines. It is important to note though, that there are no safe concentration limits per se, and the limits refer to concentrations that are known to pose significant risk. As time goes on, more and more research is showing how pollution impacts health at even low levels previously assumed as safe; these thresholds are having to be lowered. Unfortunately, this is not happening as fast as scientists might wish since economic interests often trump those of health.

As citizens, one way we can help to bring about this change is to lobby and write to our Members of Parliament, asking them what changes they intend to make to address this public health crisis that is stunting our children’s lungs and affecting their cognitive development. We also need to pressure them to improve our air quality so that we at least meet the guidelines currently in place.