Could this be related to lead exposure? Leaded gasoline was fully banned for new vehicles in 1996.
Think of it this way, not only was lead gasoline banned, but over the last 30 years we have moved manufacturing jobs to Asia (which has not seen the decline in dementia that the west has).
Manufacturing exposes workers and the surrounding area to all kinds of dusts, chemicals, etc.
I do wonder what we interact with regularly that future people would have to be paid very well to even be in the same room with, and will think we were nuts for ever thinking was OK. I'm guessing "basically anything plastic, especially if contact with food" is a likely candidate. Fire retardant chemicals in construction materials and furniture, probably.
That was DDT. Occassional exposures like that aren't linked to anything horrible in humans. It was banned for its impacts on birds, specifically their eggs. (Google "silent Spring".)
Would you apply hand sanitizer to your hands? Would you drink a bottle of it?
Found the person that didn't see Batman Begins;
If you think dancing around in aerosol'ed hand sanitizer would be okay, you've clearly never gotten alcohol in your eye, nose, or dare I say throat.
Perfume is also a really interesting one, because some of us do sneeze every time we smell Abercrombie or do start anaphylaxis around flowers or other certain plants. Which comes right around to soap, which, yes, people are allergic to dyes and fragrances in, so we make pure and hypoallergenic.
Chlorine, in pools; We've made drastic progress on that one in society in the last 30 years; from barrels of chlorine when we didn't understand it, to carefully measuring it, to now we have salt reactors that continuously meter it.
In other words, despite there being many cases of egregious mistakes in safety assumptions due to our bad understanding of science (and/or malice) in the past, we're tempted nowadays to err on the side of caution and probably overestimate the ratio of chemicals we use in our daily life that turned out to be bad, to the ones that we got right.
Sizeable parts of the populace nowadays associates the word chemical with unhealthy. Yet, they buy products that have the word "natural" on it, crafted by mixing and processing products of natural origin. But nature is full of chemicals. Mixing them and processing them, grinding them, heating them up, etc, is what chemical processing is about.
> DDT is classified as "moderately toxic" by the US National Toxicology Program (NTP) and "moderately hazardous" by WHO
> studies document decreases in semen quality among men with high exposures (generally from indoor residual spraying)
> Indirect exposure of mothers through workers directly in contact with DDT is associated with an increase in spontaneous abortions
> studies found that DDT or DDE interfere with proper thyroid function in pregnancy and childhood
> Mothers with high levels of DDT circulating in their blood during pregnancy were found to be more likely to give birth to children who would go on to develop autism
Is bioaccumulative, in fatty tissues, and a probable human carcinogen. Acute exposures in girls are said to increase x5 the probability of developing breast cancer as adult.
I am betting on combustion engines. It is ridiculous that we have hundreds of millions of those on our streets, releasing the fumes straight into the air where we live our whole lives.
Oil-based cars and trucks kill people in cities and exacerbate many illnesses like asthma. When they are gone people will wonder why they were ever allowed.
The engine tech may go away. The vehicles wont. CO2 doesn't cause asthma. Most particulates, at least from non-diesel vehicles, comes from things other than the enigne. Brake pads, tires, even the road surface itself. They all wear down, turning into dust, and get inhaled into our lungs. Electrification won't change that.
One interesting line of research is carbon fiber fires, and increasing problem as many high-end EVs are using CF to reduce weight. One CF vehicle, on fire after an accident, will release a massive amount of very fine particulates that could drift on the wind for many miles.
Then there are the knock-on social mobility benifits such as being able to switch jobs without having to move your family. Or, at a lower level, not having to rent your house/appartment/shack from your employer. Many people see cars as evil today, but realize that today is not yesturday.
Of course we don't really have traffic problems, but I wonder how we are supposed to build similar amounts of infrastructure?
Should we stop living here and move somewhere with more people?
Vastly enhanced point-to-point mobility seems like a pretty clear upside to me. Absent cars, public transportation would doubtless be better. But people would have far less flexibility in where they lived, where they went for recreation, and in many other things.
Sparing use? Buses, perhaps, emergency vehicles, and possibly delivery trucks? Probably a solid, significant improvement. Individual automobile use on public streets in and around urban areas, and all the adjustments necessary for that to happen or consequent of car-influenced growth patterns? Way, way murkier than one might initially expect, but now very expensive and difficult to reverse regardless, so we're stuck spending a lot more to travel farther and save, if we buy cheap cars and have a high paying job, a little time.
Walking and bicycles provide no protection from the elements. Depending on where you live and your occupation, the ability to travel in climate-controlled conditions and arrive with your work clothes unsoiled can be a massive utility benefit.
>>once a city's adjusted its girth to account for cars, the points most often factoring into ones point-to-point mobility are much farther apart than they'd have been without adjustments made due to widespread use of cars. Notably this doesn't include only people choosing to move farther apart, but everything being pushed apart by large setbacks from unpleasant roads
I'd argue that the land area dedicated to roads is a small portion of what forces businesses apart, and that low-density construction and inherently smaller buildings is the major contributing factor. There's only so many shops you can fit into 3-story buildings with narrow footpath-like streets between them. Hanoi is a good example of that. 48QWJ8705424314 (MGRS, paste into Google Maps)
I think the flexibility would still exist, but with a different layout
Twice. From 7yo to his early sixties. Given that horses are active participants in traffic and they will go out of their way to not step on you, they would seem to be orders of magnitude safer compared to cars.
Besides, I'd expect a professional cowboy to know how to protect himself from horses, just like a professional driver is going to have fewer car accidents.
But I quickly read through the entire thing (JSTOR still has free access: cool!) and AFAICT automobiles were far more dangerous than horses, both in absolute fatalities and presumably even more so adjusting for the number of horses and cars per capita. Toward the end the author tacks on train and streetcar deaths just to make automobile deaths look better. Indeed, it's not until the very end where the author isn't constantly drawing conclusions and providing anecdotes that seemingly contradict his own hard data. Only on a per mile basis, and then only a few decades into the age of the automobile (i.e. after traffic controls become common and pedestrians become persona non grata on the street), are automobiles indisputably safer.
Considering the utter lack of almost all traffic controls prior to the automobile and the way that pedestrians intermixed with horses, the figures are actually astonishing. More astonishing when you look at train and streetcar deaths, which were apparently incredibly lethal. I'm glad I found that paper because almost all other sources I found--which completely lacked any hard evidence--claimed horses were far more dangerous. (So does this one, though the data suggests otherwise.)
This might be a controversial opinion but I think that's a big plus. Look at old European cities with tiny streets that were mostly designed in times before carriages & cars; vs modern American cities (e.g. upper Manhattan) with large streets, a lot of driving and walking space, etc. Sure, the European model might be more romantic but the US one is definitely more functional (density isn't an issue either; London is much less dense than Manhattan).
True for tires and road, but EVs wear brake pads much slower, due to regenerative breaking.
And IC engine, when engine braking, uses virtually no fuel. Meanwhile being in neutral does use fuel.
I do think this is significantly different in ICE cars from regenerative braking in EV cars which actually stores the energy and can use it to drive the engine later. This still comes out ahead against ICE cars which don't burn much energy while going downhill.
Regenerative power for starter in frequent start-stop cycle must help a lot too.
Lights do add up too. I remember when a good decade ago day lights were made mandatory all around the year all day long. Very few cars had LED daylights so most people had to run dipped lights. Some people did backyard tests that lights add 0.5L/100km or so. Obviously now LEDs are much more efficient. On the other hand, infotainment system is ever bigger beast. But if regenerative braking power can take off the edge... Why not.
Anyway, I'm not saying that ICE is better than EV. Just saying that ICE can make use of regenerative power.
Carbon Fibre is expensive and irrelevant, and fires from it even more so, unless you want to minimise the impact of oil based cars on health in cities. Most popular EVs don't use it.
Traffic is a major source of particulates (20-30%) [1] so reducing it would help a lot, in particular diesel cars and trucks, though yes some things like rubber from tyres would only be helped by traffic reduction, simply switching to EVs would help a lot.
Moving to walking, bikes and public transport for most journeys in cities is the sustainable answer I suspect we'll end up at, and from that future our reliance on individual polluting cars will seem insane. It would require a rethink of some city planning of course, but many people happily live without cars in Europe at the moment.
0. https://airqualitynews.com/2020/02/07/air-pollution-responsi...
1. https://ec.europa.eu/jrc/en/news/what-are-main-sources-urban...
Because they're FUN. https://youtu.be/-mqXXqB7SBQ Just like eating red meat. It has consequences for you health, but bacon-wrapped filet mignon, in moderation, is worth the consequences.
A core part of our transportation network that delivers nearly every product we purchase and moves people around so they can work and have a social life.
People are going to wonder that?
Yes, people are going to wonder why it was ok to kill others with pollution by driving through cities with combustion engines.
Didn't help there was a parking garage in the building below me taking up half of the first floor.
Not sure what causes that oily dust
It's pretty exciting to be living during a transition period to cleaner energy. Just as exciting is signs of tangible evidence that this movement is indeed better for our longevity and quality of life. I'm hopeful we will keep progressing.
It's obviously not DDT now, as asserted down thread, but it definitely still goes on.
I don't know if it's less frequent today or if cities are more discrete about it considering modern paranoia. Growing up in the 90s in Florida I remember the trucks driving by on occasion, usually around dusk. If they did it late at night I'd be asleep and would be less likely to notice, so I couldn't say with any certainty how frequently they sprayed.
Also, looking at those videos, the method seems to be different and less noticeable. I remember huge, dense fogs that would envelope the whole neighborhood. In the above videos the spray disappears almost instantly.
There are any number of not-good things in tobacco smoke. The modern reality that we no longer live in a costant haze of other poeple's smoke is probably a huge factor in overall rates for many diseases.
It's more general than that. Fine particulate matter (like smoke/soot) tends to get in everywhere and with all the complex molecules in living organisms it's pretty much guaranteed that it will react with something and in large enough quantity that tends to cause disease.
https://pubs.rsc.org/en/content/chapter/9781849730822-00153/...
I doubt you encountered enough mercury, and for long enough, to be any problem unless you were doing something unusual with it. Eating a lot of fish is much more dangerous mercury-wise.
> Researchers striving to understand the origins of dementia are building the case against a possible culprit: lead exposure early in life. A study spanning 23 years has now revealed that monkeys who drank a lead-rich formula as infants later developed tangles of a key brain protein, called tau, linked to Alzheimer's disease. Though neuroscientists say more work is needed to confirm the connection, the research suggests that people exposed to lead as children—as many in America used to be before it was eliminated from paint, car emissions, water, and soil—could have an increased risk of the common, late-onset form of Alzheimer’s disease.
Of course there are some newer GA planes that use JetA (kerosene) instead, but due to heavy regulations, it's really hard to make/certify new planes, so most people still fly 40+ year old carburetor planes.
In vanishingly small quantities and even smaller concentrations (i.e. thinly distributed in the atmosphere making it hard for anyone to get a large dose) to the point which you can pick pretty much any other class of vehicles or source of lead and be reasonably sure it is causing more disease and death. I know it's easy virtue points to rag on it but leaded avgas is just not an issue. GA has no lobby or economic impact to speak of so it's not like it's sticking around through regulatory capture.
There's literally a foundation that spends tens of millions of dollars every year on small pilot interests:
It looks unleaded first became available in 1986 [1] in Ireland and leaded petrol wasn't eliminated until 2000 [2].
[1]: https://www.rte.ie/archives/2016/1011/823260-unleaded-petrol...
[2]: https://www.irishtimes.com/news/leaded-petrol-to-be-phased-o...