Air pollution has become one of the major risks to human health because of the progressive increase in the use of vehicles powered by petrol and diesel combustion spreading particulate matter (PM), oxides of nitrogen (NOx) and volatile organic chemicals (VOCs). While the risks of air pollution to health were thought to have been brought under control by the Clean Air Acts of the 1950s and 1960s, the situation of air pollution in the UK has now deteriorated to a point where it is contributing to 40,000 excess deaths each year.
Air pollution kills!
The evidence is now overwhelming that primary and secondary small and ultrafine particles (PM10, PM2.5 and PM0.1) in particular, are linked to increased all-cause mortality (29,000 deaths each year in the UK) and especially deaths from cardiovascular and respiratory disease.
Recent research shows that oxides of nitrogen (NOx: NO, NO2 and N2 O4 ) and specifically NO2 emitted in vehicle exhaust are not as benign as previously thought, increasing the number of associated deaths by up to 40,000 each year.
But it’s not just external air pollution that’s a problem to health. Air pollution indoors is just as relevant to ambient outdoor exposures although this is rarely taken into account. As a minimum, 99,000 deaths in Europe are attributed to indoor exposures, but this is likely to be a gross underestimate.
Outdoor pollutants penetrate the home, schools and workplaces and current trends to make buildings energy efficient by sealing them increases the accumulation of pollutants from furnishings, household products and cooking. In the developing world, the burning of biomass for heating and cooking is a particular problem for women and children.
Effects of air pollution on health
Air pollution has adverse effects across the life course – from conception to old age. Air pollution impairs overall foetal growth, especially lung growth; this persists across childhood, increases the risks of developing new asthma, which might not occur in its absence, and affects the heart and lungs throughout life by direct toxicity and via epigenetic mechanisms that mediate gene/ environmental interactions.
Beyond respiratory and cardiovascular disease, air pollution has adverse impacts on the development of impaired cognition, type 2 diabetes, cancers, skin ageing and even acts as a risk factor for obesity. New evidence has become known on the adverse effects of pollution on neurodevelopment. Importantly, the toxic health effects of vehicle-related pollution are greater in those socioeconomically deprived, living closer to busy roads, in poor housing, with inadequate diet, accompanying tobacco smoking and in the presence of family stress. All of these effects are further enhanced by the influence of climate change, with atmospheric conditions increasing accumulation of pollutants and formation of ozone and secondary particles.
“The harm caused by air pollution and exposure to hazardous chemicals was a new epidemic, overtaking major infectious diseases like AIDS, tuberculosis, and malaria.”Dr Margaret Chan, director-general World Health Organization (WHO)
How to protect ourselves from air pollution
As much as we may try to avoid contact with air-borne toxins it’s impossible to completely limit exposure and often we are exposed without even realising.
We enter contact with different air pollutants primarily via inhalation and ingestion, while contact through the skin represents a minor route of exposure. Air pollution contributes, to a great extent, to the contamination of food and water, which makes ingestion in several cases the major route of pollutant intake increasing toxic substance circulation around the body with deposition in different tissues. Elimination occurs to a certain degree by excretion.
Common cellular mechanism by which most air pollutants exert their adverse effects is their ability to act directly as pro-oxidants of lipids and proteins, i.e. free radical generators, promoting oxidative stress and the induction of inflammatory responses. Free radicals (reactive oxygen and nitrogen species) are harmful to cellular lipids, proteins, and nuclear- or mitochondrial- DNA, inhibiting their normal function.
Your body, in order to protect itself against the potential harmful insults from the environment, is equipped with enzymes that play a central role in the biotransformation, metabolism and/or detoxification of foreign compounds, including different kinds of pollutants.
Several natural compounds, such as vitamins C, E, and A and polyphenols, found in the majority of plant foods, interfere with or scavenge ROS concentration within cells and subsequently protect the organism from the adverse effects of oxidative stress. A recent research paper (small study numbers) suggests that B vitamins (folic acid, vitamin B6, and vitamin B12) may mitigate some of the adverse consequences.
Diets high in plant matter provide the vitamins, minerals and phytonutrients such as polyphenols that we need to support the body’s natural anti-oxidant defence systems, as well as detoxification pathways. As we are exposed to air-borne toxins through the diet it means that we need to be extra careful with the foods we eat. Ideally, we should be eating organic where we can and thoroughly washing vegetables and plant foods before we eat them.
We may also need nutrient support in the forms of supplements where the form of the nutrients is as important as the combination.
Bioactive forms of B vitamins include:
Pyridoxine-5-Phosphate (P5P) – the bioactive coenzyme form of Vitamin B6, which can be directly utilised by the body without conversion.
Quatrefolic® – a specific, clinically validated form of reduced and methylated folate. Folic acid and food folate are not biologically active and need to be converted to the metabolically active form of folate (5-MTHF) in the body. Some individuals, due to their unique genetic patterns and expression (i.e. polymorphisms), do not produce adequate or effective folate converting enzymes (Methylenetetrahydrofolate reductase – MTHFR). Quatrefolic® passes the gastric barrier and is absorbed in the gut in to support levels of bioactive folate including in those individuals who have the MTHFR polymorphism, which is implicated in certain chronic disease states.
Methylcobalamin – a naturally occurring form of Vitamin B12 that is better absorbed and retained in the tissues compared to synthetic cyanocobalamin.
For more information about forms of vitamin C supplements please read the Nutrigold blog: Vitamin C – It’s Not Just For Pirates!
Antioxidant formulations that include a mixture of organic minerals like zinc citrate, as well as plant phytonutrients may also help reduce free radical exposure in the body. Tackling air pollution is critical to for immediate and future health of populations. Whilst more needs to be asked and acted out at the government and international level the steps outlined above can go some way to helping support individuals.