A dangerous cocktail brews in our towns and cities- How tobacco smoke and vehicular emissions together contribute to wheezing in young children

Vehicular emissions and tobacco smoke are harming the lungs of young children  in our cities

When it comes to the evidence against tobacco and vehicular emissions on harming human respiratory health, it does not rain but it pours. And it keeps on coming. We have extensive evidence to show that vehicular emissions as well as tobacco smoke exposure are bad for health and it seems to start right from the fetal stage.  A new study presented in the journal Environmental Health shows that exposure to traffic-related air pollutants is associated with increased risks of wheezing in children who are exposed to tobacco smoke in fetal  life and infancy indicating an axis of villains who co-operate to exert their  harmful effects.

The study was a large prospective cohort study involving 4,634 children in Rotterdam, the second largest city in the Netherlands.  One of the largest ports in the world, it is also one of the most polluted places in the Netherlands and an apt location for pollution studies. A prospective cohort study is one that monitors a group of similar individuals –cohorts- who differ in certain factors under study over a time period in order to understand how these factors affect rates of a certain outcome- in this study, how effects of vehicular emissions, tobacco smoke exposure (in any stage starting from fetal life to the age of 3 years) affect wheezing in children.

Many cities, like this one, has air pollution monitors that helps scientist understand how air pollutants affect human health .

 Particulate matter (PM) of the size of 10 microns or less can penetrate the deepest part of the lungs such as the bronchioles or alveoli. Domestic coal combustion was once the major source of particulate emissions, but recently other sources such as road transport are important sources with diesel vehicles notably emitting increased levels. Road vehicle exhausts, off road equipment, and power plants  are  important sources of NO2.  In addition to contributing to the formation of ground-level ozone, and fine particle pollution, NO2 is linked with a number of adverse effects on the respiratory system. In this study, the exposure of children to particulate matter (PM10) and nitrogen dioxide (NO2) were assessed by analysing emission data at the home address. Parents were asked to fill questionnaires that indicated whether their children had wheezing until the age of 3 years.  Parents were also asked to provide information on whether the fetus or the baby had been exposed to tobacco smoke either through the mother or the partner smoking tobacco.

Results from the study indicated that average annual PM10 or NO2 exposure levels per year were not associated with wheezing in the same year.  Even though there were trends showing a link with PM10 or NO2 exposure levels and wheezing during the first 3 years of life, the results were not statistically significant. The researchers did not observe associations of traffic-related air pollutants with wheezing among children who were exposed to smoke during fetal life only or during infancy only. But in children who were exposed to tobacco smoke in both fetal and infant stage, PM10 or NO2 exposure levels was associated with wheezing during the first 3 years of life. The scientists did not observe associations of traffic-related air pollutants with wheezing among children who were not exposed to tobacco smoke.

There are limitations in the study, one of  which the researchers have noted viz. the possibility of ‘misclassification of air pollution assessment’ owing to the analysis only  involving  exposure levels at home addresses and not at the day care centers or other places where the child may spend days and nights. One factor that could have further added value to the study is blatantly missing- work addresses of mothers and PM 10, NO2 levels  - and whether when analysed together with air pollution exposure at home had any links to wheezing in children.

Nevertheless the study extends our understanding on how air pollution and tobacco smoke exposure contribute to the health of younger children. The  results suggest that long term exposure to traffic-related air pollutants is associated with increased risks of wheezing in children exposed to tobacco smoke in fetal life and infancy. Tobacco smoke exposure in early life might lead to increased vulnerability of the lungs to air pollution. The evidence appears to show that exposure of fetus and  infant lung to tobacco smoke primes it for damage by air pollutants leading to wheezing suggesting that the dangerous cocktail is made more potent by the ingredients together.

References

http://www.umwelt.nrw.de/umwelt/pdf/pronet/factsheets/16.pdf

Sonnenschein-van der Voort, A., de Kluizenaar, Y., Jaddoe, V., Gabriele, C., Raat, H., Moll, H., Hofman, A., Pierik, F., Miedema, H., de Jongste, J., & Duijts, L. (2012). Air pollution, fetal and infant tobacco smoke exposure, and wheezing in preschool children: a population-based prospective birth cohort Environmental Health, 11 (1) DOI: 10.1186/1476-069X-11-91

Stuck in traffic

As you sit in the rush hour queues, pity the poor guy or girl directing the traffic, and imagine the fumes they are breathing in. In Brazil, with rapidly expanding car ownership, but not necessarily expanding road space, this is an increasing problem.

A recent study* in the city of Santo Andre, part of the metropolitan region of Sao Paulo, focused on traffic controllers. The study focused on male, non smoking, traffic controllers who had been exposed for over 3 years. As the authors note, one criticism of the study is that it might actually underestimate health concerns, as unhealthy controllers were excluded from the test group to achieve homogeneity. Thus the subjects might be constitutively more able to adapt to air pollution, or just have healthier working practices.

The study concentrated on particles in the air (from dust, car exhaust etc) and ozone. The level of particulate matter has fallen in recent years, below the official limits of 50 and 25 ug/m3 for PM10 and PM2.5 respectively (PM 10 and 2.5 are different particle sizes), but that is still considered hazardous by many observers. Road dust accounts for about 30% of air pollution and is mainly composed of PM 10 particles, so the authors concentrated on this size in particular. Furthermore ozone levels are increasing, especially at times of high temperatures and low humidity. High ozone has been associated with cardiovascular disease.

They found that both PM10 particulates and ozone were associated with increased blood pressure, but in different ways. PM10 pollution caused a blood pressure rise almost immediately, which still remained 4 hours later, whilst the effect of ozone delayed for 2 hours of exposure, but was still apparent 5 hours later.

So, the traffic controllers are suffering measurable cardiovascular effects every day, continuing even when the pollution is removed, and in quite a stressful job. It might not end there. The so called "interior diesel" used in some cities such as Santo Andre has a lot more sulphur than the diesel distributed in the main cities (1,200 vs 500 ppm), which has been shown to cause endothelial disfunction, oxidative stress, and probably long term hypertension.

It's a dangerous job, standing in the middle of traffic, in more ways than one.

Sérgio Chiarelli P, Amador Pereira LA, Nascimento Saldiva PH, Ferreira Filho C, Bueno Garcia ML, Ferreira Braga AL, & Conceição Martins L (2011). The association between air pollution and blood pressure in traffic controllers in Santo André, São Paulo, Brazil. Environmental research, 111 (5), 650-5 PMID: 21570068

*P.S. Chiarellietal et al 2011. The association between air pollution and blood pressure in traffic controllers in SantoAndre, Sao Paulo, Brazil Environmental Research 111 650–655

Formula 1’s new green cloak

Formula 1’s (F1) foray into the carbon-reduction drives may not have exactly been a bombshell since it is in vogue to don a green cloak and hail this environmentally efficient attitude of reducing carbon footprint.

Trucost’s finds:
Trucost, an environmental consultancy, had conducted an exhaustive research on the full range of activities performed by and within F1 teams and their suppliers. Unsurprisingly, the carbon emissions arising from the testing and racing of F1 cars is only a small proportion (0.29%) of the total carbon chocked up by F1 as a whole (215,588 tonnes per annum in 2009, the majority being attributable to the production and supply of raw materials and parts at 50%, electricity consumption at 30%, as well as transport of team and equipment from race to race at 14%). Trucost’s environmental research analysis suggested measures to decrease carbon emissions- ergo, the Formula One Teams Association (FOTA, which comprises of all 12 current Formula One Teams) has commenced a comprehensive and externally audited carbon emissions reduction programme. It is anticipated (by Martin Whitmarch, Chairman of FOTA and Team Principal of Vodafone McLaren Mercedes) that F1 will have reduced its total carbon emissions by 12.4% compared with the 2009.

FOTA’s aims:
A small step, but some step nonetheless towards cutting the total carbon emissions of the sport. The ultimate stated aim is to address environmental problems and benefit mankind in the long run. This is to be achieved by developing new automotive technologies which may be, in time, introduced in consumer production cars. Consequently, from 2013, all entrants have to obey technical regulations, such as fitting the F1 cars with fuel efficient engines and powertrains. Furthermore, F1’s regulations will be revised to enhance and incentivise further reduction of fuel consumption and enhancement of fuel efficiency (apparently, the amount of fuel which can be used by each team could be restricted).

Therefore, the major sources of emissions reductions come from reduced electricity consumption (16.95%), reduced operational fuel use (17.92%), and reduced expenditure on parts and raw materials (20.25%).

Tips on reaching the chequered flag (apart from those stated by FOTA):

- As of yet, F1 held 19 races in 2010, around the world, and in no particular order- starting at Bahrain in March and ending at Abu Dhabi in November. As a result, there is a significant of zig-zagged travelling and carting of teams and equipment around the world, from race to race, by air, road, rail, and sea- not to overlook the devoted fans and spectators from around the world. So races could be conducted in a systematic manner, for instance, an itinerary which starts in Europe, then moves on to the Middle Eastern races at Abu Dhabi and Bahrain, and then the Asian races (Chinese, Malaysian, Singaporean, Japanese and Korean GP). Or a more austere option would be to conduct the races solely in one continent per annum.

- Decrease the number of teams.

- Alternatively, decrease the number of races.

- Imposing emissions cap on each team.

- Conducting a GP solely with green technology (this will also popularize such consumer cars).

- Use ethanol as fuel (examples being Australia’s V8 SuperCar series which uses 80% ethanol and Indy Racing which uses 100% ethanol). However, this opens a can of worms. Producing ethanol does require more energy input. Furthermore, there is an increased risk of deforestation (especially rainforests) so as to provide area for corn cultivation. If existing agricultural lands are utilised for biofuel cultivation, there could be an increase in food prices (and such affects the poor more detrimentally). A feasible solution is if biofuel is made from crop wastes or sourced by cultivation in wastelands.

- Use less(er) fuels. From my former days as an F1 fanatic, I seem to remember that teams were always keen on lesser fuel, for more fuel implies more weight, which implies slow(er) car, a veritable harakiri in a sport where every millisecond counts.

- The electricity used (also for lighting up the tracks) could be sourced from solar/wind/tidal- the former an excellent option in the Middle Eastern and Asian races.

- No more races held at night (I believe, this is the case at Singapore and Abu Dhabi).

- F1 is bound to consume a significant amount of water as well- therefore, rain water could be harvested for non-drinking purposes.

- Planting innumerable rows of trees around the F1 circuits- trees are, after all, carbon sinks.

- Creation of energy efficient and clean/green technologies (which could be translated to consumer cars), which also implies something akin to starting from scratch.

Force behind the force:
One of the drivers behind this step of FOTA is pressure from sponsors who are increasingly keen to be associated with a ‘green product’. So is it just green washing to smoothen ruffled feathers?

More likely is the possibility that this new green mantle is all thanks to new austerity measures, the consequence of the financial stress faced by F1 as a result of the recession.

My other two cents:
I would like to see how the earmarked 12.4% carbon emissions cut can be achieved.

Secondly, it does seem as if FOTA’s current plans/suggestions are targeting the measly 0.3% of emissions contributable to racing and testing of F1 cars. Shouldn’t the focus be placed on the remaining 99.7% of emissions and their sources?

Whilst teams such as Lotus and McLaren (the first to achieve a Carbon Trust certification for ‘achieving annual savings of more than 1500 tonnes of CO2 emissions) have whole-heartedly accepted the new rules, Ferrari’s disgruntled attitude towards the new cloak does make wonder whether this entire greening is a conscious change towards efficiency and environmental responsibility.

What also significantly irks me is that whilst F1 lays focus on carbon emissions, they are totally overlooking the pollutants, especially NOx and particulates (likely to be emitted from a myriad of sources, including F1 engines).

I wonder whether, as in a domino effect, F1’s new stance would inspire its fans to adopt an environmentally friendly outlook. And is it too much to hope that they wouldn’t be using petrol-based transportation to reach the race tracks? Hopefully, the future might be bright, but not be orange, but green.

Sources:

FOTA

Reuters

Image source: Pete Keen / Free Digital Photos.net