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Car tires biggest likely source of microplastics in California coastal waters

latimes.com

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Re: Car tires biggest likely source of microplastics in California coastal waters

#191

Post by newnewpdro »

cwkoss wrote: post #190
newnewpdro wrote: post #152

Earlier quoted context omitted.

Sure, in small quantities, it's not the majority of the volume they collected though.

Mining operations rarely find pure metals in the ground. Ore is a dilute mixture of rock with trace metals which must be extracted through processing.

To categorize what's found on the shoulders of highways entirely as an ore of some trace metal is to completely dismiss the rest of its content as irrelevant, despite being the bulk of its volume, in a discussion ostensibly about pollution.

Re: Car tires biggest likely source of microplastics in California coastal waters

#192

Post by souprock »

takk309 wrote: post #183
bonestamp2 wrote: post #173

Earlier quoted context omitted.

> I can't fathom why the US insists on stop signs and traffic lights everywhere. A neighborhood I used to drive through on my way to work had 4 way stops sprouting up constantly. I don't mean to sound snarky or judgemental, so please understand that is not my intention... Sometimes they do this to dissuade people from commuting to work through neighborhoods. Again, I don't mean to judge, that might be the best/safest…

I may be being a bit of a pedant but do you mean roundabout? Traffic circles and roundabouts are different. A traffic circle, in the modern sense, does not have much horizontal deflection on the entering legs. The diameter is also smaller and there is not a truck apron. A roundabout on the other hand has some form of horizontal deflection and a truck apron. Often times a traffic circle can be installed by placing a r…

Traffic circles and roundabouts don't exist. Those things are all called rotaries. The tiny ones are inherently defective, especially for large vehicles. The larger rotaries can be nice, especially when installed above a freeway that intersects with low-volume roads, but they are too costly unless the land is very cheap.

A decent use of a rotary is in Massachusetts where Drum Hill Road and Old Westford Road meet US 4 (North Road) right over top of Interstate 3. It's a 6-way intersection, with the elevated rotary helping to deal with the high speed of Interstate 3. The intersection used to be even nicer, free of traffic lights and with a smooth elliptical shape, prior to Interstate 3 being widened.

Re: Car tires biggest likely source of microplastics in California coastal waters

#194

Post by souprock »

phkahler wrote: post #172
rconti wrote: post #163

Tangentially related; I can't fathom why the US insists on stop signs and traffic lights everywhere. A neighborhood I used to drive through on my way to work had 4 way stops sprouting up constantly. The massive waste of resources involved in hauling 2 tons of steel and glass down from speed to 0, for _absolutely no reason 99% of the time_, accelerating it back up to speed again, just to do the same, over and over, bo…

Round abouts dont reduce evergy use much. If you reduce speed by 50 percent, you've still converted 75 percent of your kinetic energy to heat. I agree that many of the stopsigns are not needed.

We could recover the energy.

mgh = 0.5mvv

Cancel out the mass, round g to 10 m/s/s, assume a velocity of 30 m/s, and solve for h:

h = 45

We thus need a rotary that is elevated 45 meters above the road. That is about 150 feet. This could work for a highway, especially if it is in a road cut.

Re: Car tires biggest likely source of microplastics in California coastal waters

#195

Post by hnick »

hinkley wrote: post #61
bpodgursky wrote: post #12

Earlier quoted context omitted.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/ > Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved > Results: Almost all commercially available plastic products we sampled—independent of the type of resin, product, or retail source—leached chemicals having reliably detectable EA, including those advertised as BPA free. In some cases, BPA-free products released ch…

I was just floored when the BPA problems arose and all these people I knew were trading in one plastic bottle for a different one. I'm switching to glass and stainless and everyone else is buying more plastic . Just... don't understand why we learn so slow.

The expert interviewed here agrees with you.

https://www.youtube.com/watch?v=BIvHrC_mS_M

Big fan of this channel in general, he at least tries to back up his research (there's a recent one on the perceived danger of overheating non-stick pans).

Re: Car tires biggest likely source of microplastics in California coastal waters

#196

Post by hnick »

tyri_kai_psomi wrote: post #24
bpodgursky wrote: post #12

Earlier quoted context omitted.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/ > Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved > Results: Almost all commercially available plastic products we sampled—independent of the type of resin, product, or retail source—leached chemicals having reliably detectable EA, including those advertised as BPA free. In some cases, BPA-free products released ch…

(DISCLAIMER: I am hoping we can discuss this from a purely intellectual perspective and not bring ideology into it) I have always postulated that the increase of estrogenic compounds may have some impact on what seems to be an utter surge of reported cases of gender dysphoria amongst others other disorders that typically arise when you mess with hormonal/endocrine systems. Has there been any scientific research done…

It's accepted that male fertility rates are lower than in the past in the developed world, but further to that I recall reading that it also applies to our dogs, who are exposed to many of the same environmental factors despite a different diet in many cases.

Re: Car tires biggest likely source of microplastics in California coastal waters

#197

Post by hnick »

lotsofpulp wrote: post #80
luckydata wrote: post #40

Earlier quoted context omitted.

the last mile problem can be solved in a million different ways: bikes, taxis, uber, walking, buses... Eliminating car culture is non optional if we want to save the planet.

The last mile problem can only be solved by eliminating single family detached homes. You can only reduce the amount of energy required to move bodies so much, at some point you have to start reducing the distances traveled.

VR, then?

Re: Car tires biggest likely source of microplastics in California coastal waters

#198

Post by manigandham »

technofiend wrote: post #97
umvi wrote: post #44

Earlier quoted context omitted.

It's easy to say "use trains" when you live in a highly dense area. But America-the-continent is massive and not very dense on average. I'm not convinced trains would be viable economically like they are in Japan.

>I'm not convinced trains would be viable economically like they are in Japan. In my opinion I think rail would displace a great deal of airline traffic because air travel security is such a chore, airlines have done their very best to squeeze out every last nickel and concerns about how green air travel is or is not. Add in the fact that there is far more room per passenger in a train and with dining cars (which are…

Current technologies are too far behind in speed though. Passengers will trade better wifi, food, space, etc, in exchange for longer travel times but only up to a point. If a New York to LA trip goes from 5 to 25 hours then it's no longer viable. Unfortunately the radius that trains can be competitive barely reaches from LA to SF.

Re: Car tires biggest likely source of microplastics in California coastal waters

#199

Post by manigandham »

toephu2 wrote: post #125
jumpingmice wrote: post #35

Imagine all the problems that would be solved if someone invented a car with metal wheels, maybe one that can hold hundreds of people, goes really fast, is quiet and efficient....

The Michelin airless tire is getting close.. (still uses rubber but not nearly as much as conventional tires) https://michelinmedia.com/michelin-uptis/

They've been working on this for decades already, with the Tweel getting some attention in 2005: https://en.wikipedia.org/wiki/Tweel

It'll be a long time still before this actually gets to any kind of production use, unless regulation steps in.

Re: Car tires biggest likely source of microplastics in California coastal waters

#200

Post by liveoneggs »

sp332 wrote: post #27
liveoneggs wrote: post #20

in atlanta soil near roads tends to have a lot of lead. A daycare near me had to shutdown their playground/garden because it was testing really high in lead.

Why does it have lead?

I think because of train tracks everywhere
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