Did you know the air quality in your car may be worse than outside?

Research in London conducted by Enviro Technology Services using the Air Quality Monitoring vehicle –also known as the ‘smogmobile’, has shown that NO2 was on average 21% higher inside vehicles than outside. Dr. Ben Barratt, air quality researcher at Kings College in London, mentioned that these research findings add to the already existing evidence that vehicles do not protect against air pollution. In fact, he called on the need to better understand the health effects of this high pollution exposure for those who spend vast amounts of time in a car, such as taxi and bus drivers. Another recent research by El-Fadel M and Abi-Esber L also showed that exposure in-vehicle to VOC and PM2.5 is high, that the ventilation mode greatly contributes to the exposure,  that 3 out of 6 cars have instrusion of own engine fumes and that air pollution was higher inside new cars than outside. In fact, taxi and bus drivers have 5 times more exposure to bad air quality than people who work elsewhere.

The new car smell

A number of studies have been conducted in the past 10+ years on Volatile Organic Compounds (VOC) inside new cars. In fact, that attractive ‘new car’ smell, is off-gas derived from a mix of materials used in the treatment of leather, dashboards and seats, in addition to the glues.

There can be 50-100 VOC individual compounds in any given car, including bromine, chloride, phtalates, lead and heavy metals. All of which, according to Jeff Gearhart -research director at the Ecology Center, have been linked to cancer, birth defects, allergies, liver toxicity and impaired learning.New cars have VOC concentrations above the indoor permissible levels, but luckily they fade away in the first 6 months of a car’s life.Heat can increase these concentrations considerably.

PM2.5, mould spores, microorganisms and others

In addition to VOCs, studies which have been conducted to look into the air quality inside the cars, have found that there is also high concentration of PM2.5 and higher concentrations of carbon monoxide, benzene, toluene and fine particulate matter than in road-side monitoring stations. Moreover, studies have also found high concentrations of mould spores and bacterial endotoxins, which may induce major respiratory symptoms, allergies and are of concern to asthmatics.

How can we protect ourselves?

Ensure car ventilation to decrease the inside VOC at a faster rate, specially in the first 6 months of a car. Either have the windows down or use air conditioning regularly.

– Use air re-circulating options when stuck in traffic to avoid excessive amounts of engjne exhaust fumes coming into the car.

– Use air conditioning to control humidity and reduce mould spores and bacterial microorganisms.

– Avoid accumulation of dust, moisture/mould or residual cigarette smoke.

Sources:

Science Direct – Indoor to outdoor air quality associations with self-pollution implications inside passenger car cabins

Explorations of everyday chemical compounds – The Chemicals Behind the ‘new car smell’.

Ecology Center – New Ecology Center guide to toxic chemicals in cars helps consumers avoid a major source of indoor air pollution

NIH – Car Indoor Air Pollution

What Is It That We All Call Pollution?

Air pollution is becoming more and more present in the news, in casual conversations, in the promotion of products and in many more instances. However, are we all talking about the same thing? What exactly is it that we all call ‘air pollution’?

Air pollution is a mix of natural and man-made substances in the air we breathe which is harmful to our health, it can be any physical, chemical or biological agent that modifies the natural atmosphere. Most sources of air pollution are man-made from mobile sources such as fuel powered motor vehicles; and stationary sources such as factories, refineries, power plants and forest fires. There are also other indoor sources such as building materials and cleaning products. Air pollution, as we now know is present both outdoor and indoor.

Outdoor air pollution:
  • Fine particles (burning of fossil fuels in energy production, coal and petroleum used in vehicles)
  • Gases (sulphur dioxide, nitrogen oxide, carbon monoxide, chemical vapours and others)
  • Ground-level ozone (smog)
Indoor air pollution:

Gases emanating from:

  • Household products and chemicals, or
  • Building materials such as paint, wood, furniture (asbestos, formaldehyde, lead etc)
  • Allergens such as coackroaches, mold, pollen

The World Health Organization (WHO) in 2005 issued the ‘WHO Air Quality Guidelines’ to offer guidance and limits for the most worrying air pollutants because of their threat to human health, their widespread presence in urban areas and their relevance as precursors for other toxic components: particulate matter (PM10, PM2.5), ozone (O3), nitrogen dioxide (NO2) and sulphur dioxide (SO2).

Particulate Matter

Is a mix of solid and liquid (organic or inorganic) particles suspended in the air. It is the pollutant that affects most people and is generally composed by sulphate, nitrates, ammonia, sodium chloride, black carbon, mineral dust and water.

Ozone (O3)

Ground-level Ozone is a major component of smog, formed by the reaction of sunlight with nitrogen oxides (NOX) and volatile organic compounds (VOCs).

Nitrogen Dioxide (NO2)

NO2 is mostly the result of emissions during the combustion process (power generation, heating and engines). It is in fact, a source of nitrate aerosols that form PM2.5.

Sulphur Dioxide (SO2)

SO2 is produced from fossil fuel burning for domestic use, power generation or motor vehicles

Other components generally referred to when talking about air pollution are carbon monoxide (CO), carbon dioxide (CO2) and volatile organic compounds (VOCs), which has greater relevance when talking about indoor air pollution, although also present outdoors.

VOCs are a collection of toxic gases from solids or liquids, that are found in higher concentrations indoors (up to ten times higher). Thousands of products used indoors as construction materials, paints, varnishes, cleaning agents, activities like cooking and many more, are the source of VOCs while being used and while stored. (6) Safe levels / guidelines for exposure to VOCs are not known,, but common sense rules are that they should be kept at low levels to avoid or reduce their negative health effects, which have been well documented.

CO and CO2 are not considered as VOCs. They are both odorless, tasteless and harmful to human health but have clear differences – CO2 occurs naturally in the atmosphere and we can tolerate it in small amounts, whereas CO can cause problems even in low concentrations and is flammable.

WHO AIR QUALITY GUIDELINES
  • PM5
    10 μg/m3 annual mean
    25 μg/m3 24-hour mean
  • PM10
    20 μg/m3 annual mean
    50 μg/m3 24-hour mean
  • NO2
    40 μg/m3 annual mean
    200 μg/m3 1-hour mean
  • SO2
    20 μg/m3 24-hour mean
    500 μg/m3 10-minute mean
  • O3 
    100 μg/m3 8-hour mean
    WHO issued these guidelines as a global standard for environmental quality. Each country can adopt the guideline at its maximum standard or take interim standards that better reflect their national balance between health risks, economic decisions, technological capacities and other political and social factors.

Sources:

NIH – Air Pollution and Your Health
EPA – Pollutants and Sources
WHO – Air Pollution
WHO – WHO Challenges World to Improve Air Quality
WHO – WHO Guideline for Particulate Matter, Sulphur, Ozone…
EPA – Volatile Organic Compounds’ Impact on Indoor Air Quality