By Simon Busch, January 31, 2014

According
to a study published by India's Center for Science and Environment, the
city with the poorest air quality is actually Delhi, where air pollution
this winter was as much 60-times higher than the level considered safe.
The most harmful airborne pollutants, categorized innocuously enough as PM2.5, averaged 575 micrograms per cubic meter in the Indian capital from November to January.
That compared with a — still dangerous — concentration of 400 micrograms at peak levels in Beijing over the same period.
PM2.5 refers to the diameter in microns of nasties such as ammonia, carbon, nitrates and sulfate — particulates small enough to pass into the bloodstream and cause diseases such as emphysema and cancer.
A city such as London has an average PM2.5 level of 20 micrograms, which is considered safe.
The
CSE report goes on to say that Beijing stands a chance to permanently
relieve itself of the title of world's smoggiest city, if it continues
to make "consistent and aggressive efforts" to improve its air quality.
The report says Beijing's measures stand in stark contrast to Delhi's
weak stringency and enforcement of pollution controls.
It may seem an academic argument when you're wiping sulphate-saturated tears from your eyes or coughing up a lung while sightseeing at the Forbidden City or the Red Fort, but a new study says New Delhi has outstripped Beijing and gained the inglorious title of the world's most polluted major city.
At its worst, air
pollution in New Delhi this winter was 60 times higher than the level
considered safe, the research from India's Center for Science and Environment (CSE) reveals.
The most harmful airborne
pollutants, categorized innocuously enough as PM2.5, averaged 575
micrograms per cubic meter in the Indian capital from November to
January.
That compared with a -- still dangerous -- concentration of 400 micrograms at peak levels in Beijing over the same period.
Airborne danger
PM2.5 refers to the
diameter in microns of nasties such as ammonia, carbon, nitrates and
sulfate -- particulates small enough to pass into the bloodstream and
cause diseases such as emphysema and cancer.
A city such as London has an average PM2.5 level of 20 micrograms, which is considered safe.
Beijing looks as though
it could permanently lose lose its mantle as the world's smoggiest big
city if it keeps up the good work the CSE report describes.
The Chinese capital has
made "consistent and aggressive efforts" to improve air quality, the CSE
says, including limiting annual car sales, banning odd or even
number-plated vehicles during "red alert" pollution periods and fining
local governments for failing to curb smog.
New Delhi, by contrast, is marked by "weak ... stringency ... and enforcement" of pollution controls.

Smoke but no cigar: Beijing has lost its "most dirty" crown.
Killer cities
"Originally designed as
compact entities to reduce the length of travel ... [Indian cities] are
becoming victims of killer pollution, congestion ... and a crippling
car-dependent infrastructure," the CSE says.
It's a quote New Delhi worthies must hope doesn't make it into the next Lonely Planet.
It is, however, a decent
snapshot of the aghast impression your average neophyte India traveler
receives after stepping out of Indira Gandhi International Airport when
she thought she'd come to the land of peace, love and really full-on
yoga.
The number of cars on
New Delhi streets grows by 1,400 a day, with Indian manufacturers
obliged to fit only basic emission-cutting apparatus to their vehicles.
Smoke from the burning
of rubbish, industrial emissions and pollutants from the country's
predominantly coal-fired power stations add to the dangerous and noisome
atmosphere, the Times reports.
Delhi's report card
New Delhi buses and some
taxis might be running on natural gas, and 15-year-old commercial
vehicles have been taken off the road (although that must in some cases
include India's ubiquitous, hallucinogenically decorated trucks -- a
bitter-sweet result) but such measures aren't enough to stop many of the
city's inhabitants -- and the odd tourist -- from becoming seriously
ill, the CSE report says.
Medical studies point to
the toxic risk of smog in the wide prevalence of acute lung diseases,
eye disorders and Vitamin D deficiency leading to rickets among new
Delhi inhabitants.
Of particular concern to
tourists, a University of California, Berkeley, study cited in the CSE
report showed that pollution levels inside vehicles traveling in the
Indian capital could be eight times worse than outside.
As if riding in a New Delhi rickshaw wasn't stressful enough.
And, just to divine the
origin of that metallic taste you can't rid from your mouth when
sightseeing in Delhi, the CSE study notes that "exposure to vehicular
fume in [the Indian capital] is among the highest in the world."

New Delhi's "killer pollution": deterrent to travelers?
Would you still go?
Forewarned is forearmed.
It's up to the
individual traveler whether Delhi's world-beating air pollution is
enough reason not to see world-beating sights such as the Red Fort or
chaotically creative -- and quintessentially Indian -- Chandni Chowk
street market.
On the other hand, it
seems, you now have more reasons not to be afraid of trying Beijing
roast duck on location or venturing into the Forbidden City.
The 'dirty 10'
And the dirtiest cities of all in the world, not just the big metropolises?
New Delhi -- and Beijing -- were missing from such a list published in 2013 by the online business publication Quartz.
With almost one-third
more toxic airborne particulates than the next most polluted city,
Ahwaz, pop. 3 million -- capital of Iran's main oil producing province
-- was the dirtiest city on the planet.
Other smog-bound centers
in the ranking of 10 were Ulaanbaatar, Mongolia; Ludhiana, India;
Peshawar, Pakistan and Gaborone, Botswana.
Intrepid travelers: watch out.