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In New York City, congestion pricing leads to marked drop in pollution

(e360.yale.edu)
473 points Brajeshwar | 4 comments | 10 Dec 25 15:25 UTC | HN request time: 0.708s | source
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lkbm ◴[10 Dec 25 15:34 UTC] No.46218856[source]▶
> Particulates issued from tailpipes can aggravate asthma and heart disease and increase the risk of lung cancer and heart attack. Globally, they are a leading risk factor for premature death.

Minor nitpick, but tailpipes aren't the primary source of emissions. The study is about PM2.5[0]. which will chiefly be tires and brake pads. Modern gasoline engines are relatively clean, outside of CO2, though diesel engines spit out a bunch of bad stuff.

[0] https://www.nature.com/articles/s44407-025-00037-2

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Aurornis ◴[10 Dec 25 16:27 UTC] No.46219741[source]▶
> though diesel engines spit out a bunch of bad stuff.

Exactly. The noxious tailpipe emissions in a city are usually from diesel trucks, small vehicles like motorcycles (small or absent catalytic converters), modified vehicles (catalytic converter removed or diesel reprogrammed to smoke), but not modern gasoline ICE vehicles.

The love for diesel engines in many European countries was always confusing to me.

PM2.5 is also a broad category of particulates that come from many sources. The PM2.5 levels in the air depend on many sources, with wind being a major factor in changing PM2.5 levels. It’s hard to draw conclusions when a number depends on the weather and a lot of other inputs.

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1. SoftTalker ◴[10 Dec 25 16:49 UTC] No.46220037[source]▶
Modern diesel engines with DPF and DEF are pretty clean from a particulate and NOx standpoint. Of course there are still older diesels on the road, mainly buses and trucks. In the USA, diesel is so unpopular as a passenger car engine that it's not even worth worrying about.
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2. SR2Z ◴[11 Dec 25 13:48 UTC] No.46231321[source]▶
I don't think you can just say diesel is less popular in the US without bringing up the emissions scandals. It genuinely seems to me like companies can't deliver clean emissions and efficiency gains at the same time for it.
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3. two_handfuls ◴[11 Dec 25 15:28 UTC] No.46232559[source]▶
We would believe that except that car companies are known for lying about diesel emissions.
4. SoftTalker ◴[11 Dec 25 19:32 UTC] No.46236053[source]▶
The scandals don't matter. The number of people in the USA who buy diesel passenger cars rounds off to "nobody." There's just no point in even bothering. Supposing you could make an ultra-low emission diesel (without cheating), you'd still sell almost none.