According to the EPD's data these vehicles account for 73 per cent of total roadside respirable suspended particulates (PM10), and 34 per cent of total roadside nitrogen oxides (NOx).

This may not be rocket science but it is not wholly "unsubstantiated".

Admittedly the figures do not indicate the breakdown of engine types that contribute to emissions on any one day. But they do provide a useful indication as to where the problems lie.

Our reader's point about the dangers posed by poor exhaust systems is well taken.

And we would add the point that poorly tuned engines can emit about 20 times more in polluting emissions than the same engine when properly tuned.

Studies in the US city of Denver showed that "since 1999, one automobile in 20 emits more than the other 19 combined".
 

There's been some interest in our pantyhose item in yesterday's column in which we noted that when a Virgin Atlantic A330 evacuated passengers at London's Gatwick Airport earlier this year by emergency slides, 55 people were injured and 40 women had pantyhose fused to their skin, caused by the speed of descending the escape slides.

This led us to reflect that this apparent danger doesn't seem to have deterred female cabin crew from wearing this apparel.

However, it has been pointed out to us that when the Cathay Pacific A330-300 made an emergency landing at Chek Lap Kok in April 2010 with its two malfunctioning engines some 309 passengers evacuated by emergency slides inside two minutes.

Eight people suffered cuts and bruises from using the chutes. But after the emergency was over the big talking point among the female cabin crew was that their pantyhose was undamaged by their ordeal. The disparity in the behaviour of pantyhose in these two events surely warrants an inquiry.
 

We see that CLSA has regained top spot in the 2012 Asiamoney Brokers Poll. Last year, to its chagrin, after being top broker for a number of years, it was pushed into second place by UBS while Citi came third.

The big surprise this year was HSBC, which came second after its fifth position in 2011.

Brokerages that don't do well in these polls tend to be rather sniffy about them, saying they don't really amount to much.

Those that do well seem happy enough and issue press releases. The results are always a combination of merit and the ability to get the vote out.
 

Despite the depredations of global warming, the formation of Arctic ice doubled in October, according to the National Snow and Ice Data Centre (INSIDC) in the US.

Scientists say it is the fastest refreezing ever.

The rate of increase since the minimum this year was a near-record, resulting in an October monthly extent greater than the previous low for the month, which occurred in 2007.

However the NSIDC points out that despite the rapid growth, ice extent remains far below normal at 7.0 million square kilometres, 2.29 million square kilometres below the 1979 to 2000 average.

The fast refreeze, scientists say, is occurring because when water loses its ice cover, it allows a lot of heat to radiate out into space.

"As a result of the extra open ocean surface, we see a very fast refreeze in the Arctic," Anthony Watts wrote on his website What's Up With That.

To which one commentator observed: "A completely typical sea-ice season, of the sort happening for millions of years, given star status by satellites and a nervous world."

Have you got any stories that Lai See should know about? E-mail them to [email protected]