100LL: EPA proposed endangerment finding

[N201MKTurbo]

14 minutes ago, ilovecornfields said:

Tell me how I can use this Chernobyl data to tell my patient (or their parent) what the risk of a head or chest CT is and how this changes if they’re 6 months, 6 years or 60 years old. How about male or female?

Background radiation can’t be avoided. Radon can be mitigated and is a huge industry. Health effects from Radon (low level, low exposure, inhaled) are likely to be much different from a CT scan (high level, ultra short exposure). Again, very difficult to generalize the effects of one and apply it to the other.

Not sure how to respond to your black box comment since I’m not sure how it applies to the discussion. The difference between G100UL and 100LL is like using fire retardant vs. non-fire retardant material for your interior - not like building a plane out of lead (or whatever they make the black box out of.)

I agree I am more conservative than most when it comes to risk. I’m ok with that. I meet the less risk averse every day at work.

@N201MKTurbo - pubmed is free but most of the articles are owned by the publisher so you need an individual or institutional subscription. If you really want them I can try to pull them up and send them to you next time I’m at work. I think it’s a copyright violation to repost them publicly.

Can’t you get the same data from an MRI scan? 
 

CAT scans have been around since the 70s and X-rays have been around for over a century. The modern CT scanners use way less than the fluoroscopes of days gone by. You would think there would be enough data available. On X-ray exposure.

I would read the articles if you sent them, but I have to assume the first one uses data from before lead was taken out of car gas. Just the fact that the study was at air bases that used avgas. The military hasn’t used avgas for decades. And the fuel they used had more than 6gm/gal. The current 100LL has less than 2gm/gal.

[Pinecone]

19 hours ago, 1980Mooney said:

 still longing for that Chevy Bel Air that cost $2,166 new, no seat belts, no pollution controls, vacuum tube radio and all....

My first car was like that.  But my Dad, being a Naval Aviator did install seatbelts.

He bought it new, and then the year before I started driving, but built is a hot rod.

 

[FlyingDude]

1 hour ago, ilovecornfields said:

How about male or female?

I thought we weren't allowed to ask that anymore.  

Well, I don't actually know what kind of radiation is emitted from CT machines, but my team designed infrared and Ghz-wave incabin monitoring systems.  We had ISO standards for instantaneous and cumulative exposures and we made sure that the exposure levels were well below those.  I don't want to think that they made and sold tons of CT machines without nailing that first.

My pet peeve is about the "1-2$ cost adder" because I find it to be the generic left-wing approach of "making small sacrifices for the greater good." Putting up with unnecessary TSA screening, phone tapping, limitations on your freedoms, because one believes that one will achieve safety by making a tiny sacrifice.  Pay your dues and you will be redeemed.  Well, I believe that same safety can be achieved without requesting further sacrifices.  Gas prices are already well above the norm.  Take the lead out.  I am all for that.  But don't ask me to spend more "because I, the filthy-rich capitalist plane owner, can afford it".  Unless, you want to apply punitive taxation on all other luxury items, such as golfing, boating, designer clothing, vacation traveling, etc. and by the time you're done, anything except for basic staples will be on the "punitive taxation" list.  That's what happens in Europe with 20+% VAT.

[Shadrach]

3 hours ago, ilovecornfields said:

I know facts don’t matter these days, but the association between lead and harm is well established and so is the association between people around GA airports and lead levels.

I still think facts matter quite a bit. Taking your statement at face value it appears you are suggesting that the association between lead and harm is as well established as the association between GA airports and lead levels in those "around" them (could mean many things).  Those are two different things. The first is indeed a fact. The second may very well be true, but I have not seen a compelling study that addresses that question.  Perhaps you have.  If so, would you share?

[ilovecornfields]

59 minutes ago, N201MKTurbo said:

Can’t you get the same data from an MRI scan? 
 

CAT scans have been around since the 70s and X-rays have been around for over a century. The modern CT scanners use way less than the fluoroscopes of days gone by. You would think there would be enough data available. On X-ray exposure.

I would read the articles if you sent them, but I have to assume the first one uses data from before lead was taken out of car gas. Just the fact that the study was at air bases that used avgas. The military hasn’t used avgas for decades. And the fuel they used had more than 6gm/gal. The current 100LL has less than 2gm/gal.

With respect to the MRI scan, the answer is usually no. For things like the central nervous system (stroke, tumor) and musculoskeletal system, MR is far superior. For things like pulmonary embolism, most intrathoracic conditions and intracerebral hemorrhage, CT is better. Part of that is speed - I can get a CT in 5 minutes 24/7 but an MRI can take hours (and many hospitals don’t even have them). A lot of people can’t get MRI because of implants, pacemakers, claustrophobia. MRI also takes a long time so if you can’t stay still for 30 min you get useless images. A head CT takes about 15 seconds to acquire.

 
The current thinking is that since MRI doesn’t use any ionizing radiation the cancer risk is negligible. That might change in 30 years so I tell patients “as far as we know now, …” Unfortunately, that’s how science works. You can only act on the information you have available at the time.

You’re correct that CT scans now have less radiation than they used to or fluoroscopy does. The problem is the sheer number of CT scans people get now is huge. I’ve seen women with chronic abdominal pain or men with kidney stones in their 40s who’ve had 20-30 CT scans.  It’s not unusual to see people in their 20s with 10-15 CT scans. I’ve seen people CALL their doctor with abdominal pain and get a CT ordered without even a physical exam and patients now demand it because their Googled their condition and know what’s best for them (I’m not saying patients can’t decide what’s best for them, just that things are usually more nuanced than Dr. Google lets on).

It’s a double edged sword because the CT scanner (“the donut of truth”) can be really helpful in diagnosing life-threatening conditions and very few surgeons will take an adult to the OR without a CT scan. But then the scans are often negative in which case you get the radiation exposure but no therapeutic benefit. 

There is a calculator to guess at your risk (https://www.xrayrisk.com/calculator/calculator-normal-studies.php) but it’s only as good as the model and, again, the model is not based on ultra-short exposure to higher doses of radiation (like a CT scan).

I get it - we all have different values, beliefs, political persuasions and risk tolerance. The part I don’t get is that with all the other crap going on in the world right now why anyone would choose this topic to get all worked up over. Must be nice to have nothing more important to worry about than unleaded AVGAS.

[Pinecone]

3 hours ago, ilovecornfields said:

How do you know that GA pilots don’t have higher rates of all these conditions? One of the problems with studying small exposures and long-term effects is that you have to follow a lot of people (or animals) for a long time to quantify the effects.

For example, we know radiation is bad but we don’t know how bad. Most of our data on this comes from Hiroshima and Nagasaki but we don’t have good studies to show how this compares to ultra short exposures to high radiation environments (like a CT scan). To quantify this we would need to follow hundreds of thousands of people for their lifetimes in order to determine what effect the radiation has on their risk of cancer. We can’t do that. So we’re stuck knowing there is a risk but not how big that risk is. We do know that any level of radiation exposure can increase cancer risk and that higher radiation exposures further increase this risk so instead we try to expose patients to “as little as possible” in terms of radiation (and maybe use ultrasound or MRI instead of a CT or not get a CT at all if the risks don’t seem to justify the benefits).

Lead is the same as radiation. There is no safe established level of lead so (putting my public health hat on) the goal should be to expose people to “as little as possible.” I wear gloves when I sump the tanks, wash my hands afterwards and I barely smell the fuel (I was a chemistry major so I’ve received specialized training in smelling things). I don’t let my son sump the tanks, touch the gas caps or fuel the plane either.

I know facts don’t matter these days, but the association between lead and harm is well established and so is the association between people around GA airports and lead levels.

I certainly can’t tell anyone how they should spend their time, but as my wife (a psychiatrist) often tells her patients “is this really the hill you want to die on?” You really want to be the last person supporting leaded fuel when there is clear evidence of harm just because you (and I don’t mean you personally, @NotarPilot) are a cheap ba$tard? If $1-2/gal prices you out of aviation then you probably should pick a different hobby.

Studies no one will read:

https://pubmed.ncbi.nlm.nih.gov/24261063/

 

https://pubmed.ncbi.nlm.nih.gov/21749964/

 

https://pubmed.ncbi.nlm.nih.gov/16181659/

 

We  DO know the effects of radiation.  Both lower dose, longer term exposures and high dose short term.

And the same issues with determining low dose effects occur with other agents than radiation.  You need to follow a LOT of people, a LONG time and you have to have access to an equal number with no exposure.  And then have to make sure that you actually have causality, not just correlation.  

There was a study published about the effects of extremely low frequency RF radiation from power lines.  Based on the voltage and number of phases on the distribution through neighborhoods.  After it was published, another person showed that the data could have been used to compare the same health effects to the number of cars going by per day.  This was since the power lines follow roads and the further you get into neighborhoods, the lower the transmission line voltage and also less traffic as there are less houses served by that road.

In general, EPA uses a linear dose response curve model.  That is, they consider the only safe dose to be 0.  But a lot of things are actually beneficial or required in low doses.  Such as Zinc.  A lot of zinc is bad.  If you had a diet of 0 zinc, it would also be bad.

Lead has been implicated in developmental issues in children.  In adults, there are less issues, especially in low doses.  And lead that does get into an adult, is secreted over time.  In the old days, lead miners would be exposed to high levels and have health effects.  The "cure" was to have to not work in the mines, but they would spend their shift walking around in a very hot room.  This would increase the rate the lead was excreted, and get them back to work in the mines faster.  Not exactly acceptable practice today.

 

[Shadrach]

3 hours ago, ilovecornfields said:

I know facts don’t matter these days, but the association between lead and harm is well established and so is the association between people around GA airports and lead levels.

I still think facts matter quite a bit. Taking your statement at face value it appears you are suggesting that the association between lead and harm is as well established as the association between GA airports and lead levels in those "around" them (could mean many things.  Those are two different things. The first is indeed a fact. The second may very well be true, but I have not seen a compelling study that addresses that question.  Perhaps you have.  If so, would you share?

[ilovecornfields]

19 minutes ago, FlyingDude said:

I thought we weren't allowed to ask that anymore.  

Well, I don't actually know what kind of radiation is emitted from CT machines, but my team designed infrared and Ghz-wave incabin monitoring systems.  We had ISO standards for instantaneous and cumulative exposures and we made sure that the exposure levels were well below those.  I don't want to think that they made and sold tons of CT machines without nailing that first.

My pet peeve is about the "1-2$ cost adder" because I find it to be the generic left-wing approach of "making small sacrifices for the greater good." Putting up with unnecessary TSA screening, phone tapping, limitations on your freedoms, because one believes that one will achieve safety by making a tiny sacrifice.  Pay your dues and you will be redeemed.  Well, I believe that same safety can be achieved without requesting further sacrifices.  Gas prices are already well above the norm.  Take the lead out.  I am all for that.  But don't ask me to spend more "because I, the filthy-rich capitalist plane owner, can afford it".  Unless, you want to apply punitive taxation on all other luxury items, such as golfing, boating, designer clothing, vacation traveling, etc. and by the time you're done, anything except for basic staples will be on the "punitive taxation" list.  That's what happens in Europe with 20+% VAT.

I’m not sure you read the earlier posts. We know exactly what kind of radiation is emitted from CT scans, exactly what the dose is and the part of the body receiving that dose. This is documented on every scan.

What we don’t know is the magnitude to which these scans cause long term health effects and in a prior post I explained what it would take to show that and why we’re not going to have that information.

With respect to your political comments, I’m not going to respond to them. If that’s how you see the world then nothing I say or do is likely to change that.

[M20F]

8 minutes ago, ilovecornfields said:

Must be nice to have nothing more important to worry about than unleaded AVGAS.

I worry more about ethanol, let’s get this thread another 10-15 pages.  

[Ragsf15e]

https://generalaviationnews.com/2022/09/25/how-the-search-for-unleaded-avgas-is-like-two-elephants-mating/
 

this is a good read about the difficulties, liabilities and expense of making 100ll and g1000ul.  Some things to consider…

[FlyingDude]

1 hour ago, ilovecornfields said:

With respect to your political comments, I’m not going to respond to them. If that’s how you see the world then nothing I say or do is likely to change that.

We don't have to agree on everything.  We can still be friends.

We both want lead out of avgas.  You are willing to pay more, I am not.  No biggie.

 

[N201MKTurbo]

2 hours ago, ilovecornfields said:

There is a calculator to guess at your risk (https://www.xrayrisk.com/calculator/calculator-normal-studies.php) but it’s only as good as the model and, again, the model is not based on ultra-short exposure to higher doses of radiation (like a CT scan).

Well, the calculator was kind of interesting. It seems like there is over a 100/1 difference between the worst CT dosage (head and neck) and the lowest (hand) At my age getting 20 of the head and neck scans brought my cancer risk almost up to the risk of dying in a car accident.

So, giving one of your patients a bunch of CT scans is about equivalent to giving them a pilots license.

[Pinecone]

1 hour ago, 1980Mooney said:

We had a '55.  After a panic stop that threw me into the unpadded metal dash my dad put in seatbelts also. The '62 Chevy didn't come with seatbelts either.

Our 63 Chevy Impala wagon had them from the factory.

Our 71 Monte Carlo had shoulder harnesses, but they were separate from the seatbelt and were a royal PITA.  I don't think they ever got used. 

73 Capri had real 3 point with inertial reel shoulders.  As every car since then.

[ragedracer1977]

13 hours ago, Shadrach said:

I still think facts matter quite a bit. Taking your statement at face value it appears you are suggesting that the association between lead and harm is as well established as the association between GA airports and lead levels in those "around" them (could mean many things.  Those are two different things. The first is indeed a fact. The second may very well be true, but I have not seen a compelling study that addresses that question.  Perhaps you have.  If so, would you share?

None of the studies really say that the increase in lead levels has anything to do with airports.

 

One I read (can’t remember the state, but maybe Tennessee or one of the Carolinas) studied an entire state. They found that kids living near airports had elevated lead levels. Unless you’re a pilot, or familiar with airports, you wouldnt even notice that kids living within 1/2 mile of the big class B had nearly identical elevated levels as the kid that lived within 1/2 mile of a grass strip in the middle of nowhere that has zero based aircraft and probably doesn’t see more than 20 operations a year.

 For some reason, the study authors left out how many operations there were and let a reader who doesn’t know a thing about airplanes believe an airport is an airport.

 

 

[ragedracer1977]

https://ibb.co/N3MY9XR

Have a look at this chart. I believe this data was collected for the entire year of 2011 or 2012. 
 

look at the airports. how is it that a tiny airport with a 2600’ runway has nearly ten times the airborne lead as an airport with parallel runways, and about 5 times as many operations?

 

 How is it that the airports with the highest concentrations are all relatively closely located in CA? And no where near the busiest.
 

If you know airports and operations, this chart alone heavily suggests to me that aircraft are NOT the cause of elevated lead.

Edited October 13, 2022 by ragedracer1977

[NotarPilot]

19 hours ago, ilovecornfields said:

How do you know that GA pilots don’t have higher rates of all these conditions? One of the problems with studying small exposures and long-term effects is that you have to follow a lot of people (or animals) for a long time to quantify the effects.

For example, we know radiation is bad but we don’t know how bad. Most of our data on this comes from Hiroshima and Nagasaki but we don’t have good studies to show how this compares to ultra short exposures to high radiation environments (like a CT scan). To quantify this we would need to follow hundreds of thousands of people for their lifetimes in order to determine what effect the radiation has on their risk of cancer. We can’t do that. So we’re stuck knowing there is a risk but not how big that risk is. We do know that any level of radiation exposure can increase cancer risk and that higher radiation exposures further increase this risk so instead we try to expose patients to “as little as possible” in terms of radiation (and maybe use ultrasound or MRI instead of a CT or not get a CT at all if the risks don’t seem to justify the benefits).

Lead is the same as radiation. There is no safe established level of lead so (putting my public health hat on) the goal should be to expose people to “as little as possible.” I wear gloves when I sump the tanks, wash my hands afterwards and I barely smell the fuel (I was a chemistry major so I’ve received specialized training in smelling things). I don’t let my son sump the tanks, touch the gas caps or fuel the plane either.

I know facts don’t matter these days, but the association between lead and harm is well established and so is the association between people around GA airports and lead levels.

I certainly can’t tell anyone how they should spend their time, but as my wife (a psychiatrist) often tells her patients “is this really the hill you want to die on?” You really want to be the last person supporting leaded fuel when there is clear evidence of harm just because you (and I don’t mean you personally, @NotarPilot) are a cheap ba$tard? If $1-2/gal prices you out of aviation then you probably should pick a different hobby.

Studies no one will read:

https://pubmed.ncbi.nlm.nih.gov/24261063/

 

https://pubmed.ncbi.nlm.nih.gov/21749964/

 

https://pubmed.ncbi.nlm.nih.gov/16181659/

 

You bring up many very good points. At the very least I will be wearing gloves when I pump and sump the gas. 
 

As far as the studies go, you’re right. I guess I just assumed there would have been a study of leaded fuel and the effects on GA owners and pilots. Hell, it seems like there have been studies on everything else on this planet, why not that? 

[Shadrach]

19 hours ago, ilovecornfields said:

I’m not sure you read the earlier posts. We know exactly what kind of radiation is emitted from CT scans, exactly what the dose is and the part of the body receiving that dose. This is documented on every scan.

What we don’t know is the magnitude to which these scans cause long term health effects and in a prior post I explained what it would take to show that and why we’re not going to have that information.

With respect to your political comments, I’m not going to respond to them. If that’s how you see the world then nothing I say or do is likely to change that.

Which comment was political?

How precisely does he view the world?

[A64Pilot]

We all KNOW that agricultural chemicals like defoliants, fungicides cause cancer correct? It a well known fact, right?

The NAAA https://www.agaviation.org has paid for several cancer studies over the years to asses the risk and to come up with mitigation strategies for the pilots and loaders who are of course exposed to high levels of these chemical very frequently.

Believe it or not but there wasn’t any significant differences between them and the general population, so the survey must be incorrect, so they had other surveys taken by other means.

There just didn’t seem to be any higher incidence rate, even among the older pilots that have been flying through the spray without respirators for decades. As you fly passes through the same field, you fly through some of your spray from the pass before, reason why Ag planes have good windshield washers and wipers.

I’m not making any claims, I’m not educated enough to do so, but it’s odd that the Ag pilot population isn’t eaten up with several forms of cancer. If nothing else Roundup which is used to defoliate just about everything ought to be getting them

Lead is a natural not rare metal, it exists in higher concentrations in some areas than others. I’m not saying that being natural makes it good or safe, but I’m sure there are detectable amounts of airborne lead that occur naturally, be interesting to know if there have been any studies of airborne lead not around airports?

Finally I’ll leave you with this thought, aircraft mechanics are exposed to a whole lot more of the leaded fuel and lead, heck we wash parts in it sometimes, and change oil that’s full of lead, bead blast valves, pistons, spark plugs that are fouled with lead. 

Be interesting to see if there has been any health surveys on aircraft mechanics? Or tests of blood levels compared to the general population.

A possible issue I have is, that often we get rid of some chemical because it’s bad, but later the replacement is found to be worse often for completely other reasons, I know there has been a lot of concern over aerobatics in auto fuel for a long time, just Google it.

In 1982 when I was an Army helicopter mechanic we used Acetone for almost everything, then it got banned because it was bad, MEK replaced it, years later it was found to be worse than Acetone, so did we bring Acetone back? Of course not we replaced MEK with MIK. I bet by now MIK has been found to be worse than MEK, and Acetone.

[N201MKTurbo]

19 minutes ago, A64Pilot said:

 

I used to work on Joe Henderson's (RIP) AirTractors. One day he was about to spray a field and there were some people in the middle of it. He made a few passes over them, but they wouldn't leave, so he sprayed anyway. 

They complained to the ADEQ about how sick they got. they clamed they were throwing up and got sores all over them. The ADEQ contacted Joe and asked what he was spraying. The answer was alfalfa seed.

https://www.newspapers.com/clip/72609644/arizona-republic/

http://www.getipm.com/articles/arizona-spray.htm

[A64Pilot]

The funny thing is I know several of those pilots in the second article, and at least one I wouldn’t think would be reckless etc. Probably shouldn’t name names.

 

[Hank]

2 hours ago, N201MKTurbo said:

I used to work on Joe Henderson's (RIP) AirTractors. One day he was about to spray a field and there were some people in the middle of it. He made a few passes over them, but they wouldn't leave, so he sprayed anyway. 

They complained to the ADEQ about how sick they got. they clamed they were throwing up and got sores all over them. The ADEQ contacted Joe and asked what he was spraying. The answer was alfalfa seed.

That's the entitlement mindset. "We were here first, we aren't leaving for you." Followed by thoughts on how to get rich quick at someone else's expense. I just hope they had actual doctor bills they paid out of their own pockets for the con they tried to run . . . .

[jaylw314]

On 10/12/2022 at 9:04 AM, Pinecone said:

We  DO know the effects of radiation.  Both lower dose, longer term exposures and high dose short term.

The number of cases of diagnosed acute radiation syndrome in history numbers only a few thousand, and the number of deaths from it I'm guessing is only a couple hundred, with extremely large variations in quality and quantity of exposure.  That is not a sufficient base to draw good conclusions from.

The converse of low dose, long-term exposure results in very tiny percentage of consequences, and any time that occurs, it is also very difficult to draw good conclusions about cause and effect.

I'm not sure radiation exposure is a terribly good comparison to lead for those reasons. 

Edited October 13, 2022 by jaylw314

[jaylw314]

On 10/12/2022 at 12:33 AM, NotarPilot said:

I’m not trying to be smart here and this is a sincere question but if lead based aviation fuel was this tremendous danger to people wouldn’t small GA piston owners and pilots have demonstrably higher levels of cancer, anemia, weakness, and kidney and brain damage than the rest of the public that isn’t directly around this stuff? I know some of you may argue, based on my previous posts, that I’ve suffered some brain damage but let’s think of me as the outlier. 
 

Any of you ever get a little bit of a gas on your hands or fingers while sumping the fuel out of your tanks before a flight?

I'd say this effect on our generation is probably washed out by the fact that we exposed EVERYONE to higher levels of lead during childhood.  It's really only kids in the last 30 years who've had the benefit of lower lead exposure.

How often did we complain that only kids could figure out how to program VCR's?  Maybe that was the reason!   

[jaylw314]

3 hours ago, A64Pilot said:

Finally I’ll leave you with this thought, aircraft mechanics are exposed to a whole lot more of the leaded fuel and lead, heck we wash parts in it sometimes, and change oil that’s full of lead, bead blast valves, pistons, spark plugs that are fouled with lead. 

One of the studies @ilovecornfields listed was specifically regarding aircraft mechanics.

The counterargument is that contact exposure is limited in area and can be practically mitigated by hand-washing, protective gear and safety practices.  Airborne exposure doesn't have those upsides

[Shadrach]

2 hours ago, jaylw314 said:

One of the studies @ilovecornfields listed was specifically regarding aircraft mechanics.

The counterargument is that contact exposure is limited in area and can be practically mitigated by hand-washing, protective gear and safety practices.  Airborne exposure doesn't have those upsides

Everyone on this forum over the age of thirty was exposed to leaded auto gas exhaust to some degree. Those of us born in the 70s or earlier played in driveways where cars burning leaded gas were started, idled and shut down on a daily basis. If you lived in a major city from about 1950 to 1985 you were surrounded by leaded auto fumes all the time.  Being in proximity to leaded auto fuel was once a way of life for every family in this country and indeed most the world.
If leaded Avgas exhaust from run up areas and departure corridors is dangerous to home owners 1000 yards away, then everyone over the age of 50 should have lead poisoning. Yet there’s no evidence for that. I agree that lead should go away. I am perplexed that as a nation, we lived with it as our main source of auto fuel for nearly 4 decades without poisoning the whole population.