8 January, 2017

Another brainless study about living near a highway being bad for you

The Left hate major roads and motor vehicles generally but make heavy weather of condemning them.  So they are always keen to show that roads are bad for your health. And living near a busy road may indeed be bad for you.  There are some theoretical reasons which could lead to that conclusion.  And there seem to be an unending stream of studies "confirming" the connection. But they are all rubbish, as is the one below.

Why? Because they all fail to account well or at all for an obvious confounding factor:  Poverty.  As has been shown many times, the poor have worse health all-round and are more likely to live near a busy road.  "Noise affected" real estate often trades at a one-third discount.  Living near a busy road is a lot cheaper and often it is the only place where the poor can afford to live.  So to show any association of traffic on health, you have to control for income.  If you do not, you could be looking at an effect of poverty, not an effect of traffic.

Statistical control would have been possible but the study reported below did not control for ANYTHING.  I would never have passed it for publication were I the journal editor concerned. Marie Pedersen is a dimwit

Expectant mothers living close to busy roads are at greater risk of serious complications in pregnancy, experts have found.

Pre-eclampsia – a condition suffered by 42,000 pregnant women in Britain each year – is made more likely by noise and pollution from roads, according to a large study.

Researchers believe the toxins from vehicles and sound of traffic from nearby roads may increase stress levels and cause inflammation that leads to rising blood pressure associated with the condition.

The Danish study of 73,000 women - the first to establish a link between traffic and pre-eclampsia - adds to growing concerns about the health impact of air and noise pollution.

Pre-eclampsia affects around 6 per cent of pregnancies in the UK - and in severe cases can lead to stillbirth or maternal death.

Researchers found that for every 10-decibel increase in noise from traffic – roughly a doubling in audible volume - there was a 10 per cent increase in the risk of pre-eclampsia and high blood pressure problems in pregnant women.

Similarly, for every 0.01 micrograms of nitric dioxide from car exhausts in a litre of air - a tiny increase - the risk of the condition rose by 7 per cent.

Study leader Professor Marie Pedersen, of the University of Copenhagen, said: ‘The rise in risk we saw is significant in terms of impact on a population level, as a 10-unit increase in pollution and noise is very small.’

Professor Pedersen said her study shines new light on the root causes of the condition, which has been poorly understand in the past. She said: ‘Air pollution causes inflammation and oxidative stress, which has been linked to damage to blood vessels, immune system changes and elevated blood pressure.

She and her colleagues, whose work is published in the journal Epidemiology, studied data collected from 72,745 pregnancies in Denmark and modelled the noise and air pollution at their addresses.

SOURCE

The journal article is "Impact of Road Traffic Pollution on Pre-eclampsia and Pregnancy-induced Hypertensive Disorders"






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