Small Children and Avgas: Lead exposure

[Seth]

I may be taking my just turned 1 year old and wise to a family event in North Carolina in July. That's 6-7 hours of driving plus stops (so 10 hours each way) or a two hour flight each way.

This is the exact mission for my Mooney!  However, the idea of both oxygen depletion in small children and exposure to leaded Avgas worries me.

I've done a lot of research on my own, but from the collective Mooney Spaxe environment, what are the facts?  What are your individuals practices?  And why?

 

We'll go on at least one flight prior to ensure she's comfortable flying. I have to figure out earplugs and child headsets or sound safety equipment.  I'll post my inteoductoon of my daughter to flying plan in a separate thread.

For this thread again, what are the lead poisoning facts from Avgas and what are your practices and why?

 

Thanks

 

-Seth

[mooniac15u]

The toxicology of lead exposure in general aviation is complicated by the fact that lead is present in multiple forms including tetraetyl lead in the gas as well as lead oxide and lead bromide in the exhaust. 

Exposure to the tetraetyl lead should likely be a non-issue as long as you keep her away from direct contact with the fuel. 

Exposure to lead oxide and lead bromide would probably be dependent on whether your exhaust system leaks. With a well functioning exhaust I would expect the lead salts to be dispersed pretty rapidly. 

Disclaimer: I'm a chemist not an MD or OHS specialist. 

[carusoam]

Some ideas...

1) Hearing safety: Somebody recently posted some pictures of their new twins with the pink and blue children's headsets/ear protection...

My kids sat in the back of the C and used ear cup style noise protectors from Sears/craftsman.

There is not much high level noise in the back seats of an M20C.

what you can do to measure it...  The IPhone has an app for that.  90 decibels is the usual limit.  Know the iPhone is not the best device for this.

2) Lead ingestion: Sure, if your smelling exhaust, your getting CO, and some lead compounds are floating around...  It is going to take a lot to be a serious problem.  Anyone over 50 has had a lot of leaded gas in their system from automobiles...

what you can do to measure it: use a carbon monoxide sensor/alarm to measure the CO and assume there is going to be some lead compounds that come with it.  I can get my alarm to peep if I sit around idling.  It's a reminder to move on...  Remember the short exhaust stack is about your feet, not 15' behind you...

3) be aware of the nasal congestion issues that some kids can have.  Slow descents to avoid serious aches and pains.

 

Overall, my kids seem OK.  One is in highschool, the other went to engineering school.  

Probably not a statistical valid discussion.  But, it's what I have...

Best regards,

-a-

[DXB]

Fantastic question - leaded gas is perhaps the single most bothersome thing to me about this flying hobby, even without having a child to expose to it.  The amount of tetra-ethyl lead in 100LL is roughly on par with the amount that was in leaded automotive gas through the 1970s, and so there is decent toxicology data I think from people having decades of exposure.  The tetraethyl lead in our gas is very readily absorbed through inhaled fuel vapor and skin contact, as is the lead in combustion products from it in inhaled exhaust. I hate breathing it or getting it on my hands, even though the risk from occasional low level exposures in adults seems fairly low.  Regardless I try to avoid as much as possible. Even getting a  little splash when sumping the tanks or filling up really bothers me, though wearing gloves every time doesn't feel practical. I do use the GATS jars to sump because I think the splash exposure is less. It is a very potent neurotoxin and kidney toxin in large quantity in adults and accumulates over time. Cognitive development in children seems quite sensitive to it even at much lower level exposures, and so I would strive for the absolute minimum exposure possible - probably just means never letting them fill up, sump the tanks, or roll around on the hangar floor. It was banned from automotive gas in the US for compelling health reasons, not just because it kills the catalytic converters in modern cars. 

I think it's a disgrace that we haven't replaced it yet in Avgas.  But I look forward to reading more about it on this thread as I am hardly an expert.  Any toxicologists here???

47 minutes ago, Seth said:

 However, the idea of both oxygen depletion in small children and exposure to leaded Avgas worries me.

Luckily I doubt you need to sweat the oxygen depletion part.  Kids adapt fine and can live permanently at elevations that mimic the O2 levels experienced during normal flying without issue.

[mooniac15u]

Just now, DXB said:

Fantastic question - leaded gas is perhaps the single most bothersome thing to me about this flying hobby, even without having a child to expose to it.  The amount of tetra-ethyl lead in 100LL is roughly on par with the amount that was in leaded automotive gas through the 1970s, and so there is decent toxicology data I think from people having decades of exposure.  The tetraethyl lead in our gas is very readily absorbed through inhaled fuel vapor, skin contact, and (ugh) inhaled exhaust. I hate breathing it or getting it on my hands, even though the risk from occasional low level exposures in adults seems fairly low.  Regardless I try to avoid as much as possible. Even getting a  little splash when sumping the tanks or filling up really bothers me, though wearing gloves every time doesn't feel practical. I do use the GATS jars to sump because I think the splash exposure is less. It is a very potent neurotoxin and kidney toxin in large quantity in adults and accumulates over time. Cognitive development in children seems quite sensitive to it even at much lower level exposures, and so I would strive for the absolute minimum exposure possible - probably just means never letting them fill up, sump the tanks, or roll around on the hangar floor. It was banned from automotive gas in the US for compelling health reasons, not just because it kills the catalytic converters in modern cars. 

I think it's a disgrace that we haven't replaced it yet in Avgas.  But I look forward to reading more about it on this thread as I am hardly an expert.  Any toxicologists here???

Luckily I doubt you need to sweat the oxygen depletion part.  Kids adapt fine and can live permanently at elevations that mimic the O2 levels experienced during normal flying without issue.

I believe that for most children the harmful lead exposure from leaded auto gas came from the resulting large quantities of lead in the environment rather than acute exposure to the gasoline. 

[Hank]

I always read that the amount if lead in 100LL is a fraction of what was in regular gas in the 60s and 70s. Don't let her play in a fuel puddle in the ground, or your sample cup / dipstick and she should be fine. Just ask any of the people here who grew up flying with their parents on 100 Octane before the introduction of the Low Lead formula . . .

Fly everyone to the family in the Carolinas. The greatest danger will be your decision making along the route regarding weather, terrain, other air traffic, etc. Be safe and have fun! I grew up making epic 10-12 hour family road trips, and doing it in 2 hours is a large part of why I bought an airplane.

[DXB]

Interesting historical perspective on gas and tetraethyl lead toxicity...

http://www.wired.com/2013/01/looney-gas-and-lead-poisoning-a-short-sad-history/

wikipedia info on amount of lead in Avgas (sorry- too lazy to look up for real- I'm sure someone here will correct if wrong):

"TEL remains an ingredient of 100 octane avgas for piston-engine aircraft. The current formulation of 100LL (low lead, blue) aviation gasoline contains 2.12 grams of TEL per gallon, half the amount of the previous 100/130 (green) octane avgas (at 4.24 grams per gallon),^[39] but only slightly less than the 2.2 grams per gallon historically permitted in automotive leaded gasoline and substantially greater than the allowed 0.001 grams per gallon in automotive unleaded gasoline sold in the United States today.^[40]  "

[Hank]

I believe wiki is referring to the specification limits for TEL, not the amount actually in it. See if you can find a recent analysis, I recall seeing numbers in some of the many Unleaded Replacement Fuel articles a couple of years ago that what is often produced now, the amount of TEL starts with "0" rather than the permitted "2."

[DXB]

1 hour ago, Hank said:

I believe wiki is referring to the specification limits for TEL, not the amount actually in it. See if you can find a recent analysis, I recall seeing numbers in some of the many Unleaded Replacement Fuel articles a couple of years ago that what is often produced now, the amount of TEL starts with "0" rather than the permitted "2."

Certainly appears you are correct, but still can't find now much is actually in it. I imagine it's somewhat refinery and batch specific since the goal is obtaining the octane rating?  Out of my depth here...

It is worth noting though that the CDC states that there is no known safe level of exposure to lead for children.  

[Yetti]

I was one year old in the 60s. I am sure that I was exposed to leaded exhaust alot.  I am just fine. At least most people would say so.

[bradp]

Lead testing is common and easy to do.  There is also chelation therapy available.  Talk to you pediatrician at your next visit.  

[Ron McBride]

I have been flying as a child since 1968 and since.   I have been around construction most of my adult life and before more regulations, and have been reloading lead ammo for years. I was tested last year, and did not show any levels of lead.

My understanding is, that as adults we will make new brain cells to replace the ones damaged by lead, but CHILDREN under 8 can not.???   This is the reason for all of the restrictions today.

I am not an expert or a Doctor.  Please double check for your self.

Ron

[steingar]

Oh for Odin's sake!  Children grow up and live in Lhasa!  How much higher are you going to be flying that that?  Lots of us grew up with leaded gasoline, in cities with all kinds of cars spewing the stuff everywhere.  And believe me, most of the cars were more poorly maintained that our aircraft.  We're still here.

Lots of things to worry about with a child, the job of a parent isn't an easy one.  This dog just don't hunt.

[N201MKTurbo]

Unfortunately, TEL is the best anti-knock compound ever found. They have been looking for a replacement for almost 100 years. If they haven't found it yet I don't think they will. there are two choices, reduce the performance of our engines or burn lead.

I know Swift and the lot are trying to make lead free 100 octane. Whatever they come up with will be inferior and more expensive then what we have now.

[carusoam]

Summary...?

1) Lead is bad.

2) Lead isn't going away soon.

3) Lead poisoning is serious to brain cell development.

4) Minimizing contact with the fuel and exhaust is the best alternative.

5) don't let fuel seep into the cabin.  The nose is a good monitor for most people.  If you smell fuel when you open the plane's door, that may be a hint.  Fuel level sensor seals were originally made of cork. After 50 years, it was common to leak fuel into the cabin leaving a blue stain on the carpet.  Really easy to fix.

6) don't let exhaust seep into the cabin. Aroma and carbon monoxide sensors are pretty good ways to tell.  Sealing the cabin from the outside has improved over the years.

7) know that some noses are not as sensitive as others.  Sensitivity changes with age

8) ignoring it doesn't make it go away. Some people don't know to do anything about it.

9) The unlucky kid I went to highschool with lived near the gas station.  His house used well water.  The gas station had leaky tanks. It probably took 16 years to find out his problems were caused by lead poisoning.  According to reports: The aroma of gasoline could be smelled in the water.    Circa 1980...

Other examples are caused by ingestion of lead based pigments in old paints.  Small amounts can be serious.

10) ingesting fuel and it's byproducts of combustion are best to be avoided when possible. not just the Pb...

braincells take a really long time to replace. Try not to kill any knowingly or accidentally, 

That's a tough topic to cover.

Best regards,

-a-

 

[Tom]

13 hours ago, DXB said:

Luckily I doubt you need to sweat the oxygen depletion part.  Kids adapt fine and can live permanently at elevations that mimic the O2 levels experienced during normal flying without issue.

"Normal flying" needs to be qualified.  There's a lot of very uncomfortable findings in research on hypobaric hypoxia. 

What altitudes are we talking about?

For the lead keeping the plane clean, keeping the kids away from fueling operations and components, and being careful with hand in mouth activities is about all you can do.  I wouldn't sweat this.

 

 

[Marauder]

This discussion about the effect of leaded gas finally explains something. As a kid, growing up when leaded gas WAS the only gas available, it is probably the reason I am brain damaged. Why else would I spend the tens of thousands of dollars on a 40 year airplane?

[Andy95W]

1 minute ago, Marauder said:

This discussion about the effect of leaded gas finally explains something. As a kid, growing up when leaded gas WAS the only gas available, it is probably the reason I am brain damaged. Why else would I spend the tens of thousands of dollars on a 40 year airplane?

I knew there was a logical explanation for my behavior.  Now to convince my wife...

[aviatoreb]

There are all sorts of noxious chemicals in fuels.  I would guess, but I don't know, that if there were enough exposure to measurably increase lead, then there would also be poisoning due to the many other ugly chemicals.    Keep your CO monitor running and if it is clean than I would guess, again I don't know, but then you would be also free from all those other products in the exhaust stream including lead.

Here is a lead worry I had when my kids were growing up here in a small town near all sorts of lovely rivers.  My oldest son grew up just the ultimate fisherman.  Fly fishing.  He would fish just about every day in the summer, since age 6 or 8.  He eventually was even making his own flies.  Well silly me, I saw one day when he was about 12 that he was pinching little lead weights onto his line by crushing them with his teach.  Then it hit me, also just handling the stuff it rubs off on his fingers.  Talk about lead exposure - put little lead balls in your mouth!  And fingers and eat with them.  Well...let's just say I got him a pair of tweezers.  He seems ok.  That still didn't seem to ruin him.  He was valedictorian.  And, still in passionate about rivers, he has gone to Cornell where he just finished his first year, majoring in environment and sustainability. 

[DXB]

43 minutes ago, Tom said:

"Normal flying" needs to be qualified.  There's a lot of very uncomfortable findings in research on hypobaric hypoxia. 

What altitudes are we talking about?

For the lead keeping the plane clean, keeping the kids away from fueling operations and components, and being careful with hand in mouth activities is about all you can do.  I wouldn't sweat this.

 

 

Yes of course normal flying means no hypoxia,  using O2 with the delivery system  appropriate for a given altitude along with routine pulse oximetry.    

[kerry]

My 94 year old friend has been around aviation since he was born.  His Father was a WWI fighter pilot and my friend grew up around leaded fueled airplanes probably more than the average aviation folk.  My friend who is 94 is as healthy as can be expected for his age.  I find it humorous every time I read or hear the bad effects leaded Avgas has on our children. 

[1964-M20E]

Good to be concerned but fly there and don't think about it anymore.

 

I can remember putting my face in the exhaust stream of a running car in the 70's I have no obvious problems except for that aggravating twitch.

 

 

 

 

Edited June 9, 2016 by 1964-M20E

[mooniac15u]

If you have serious concerns about lead exposure you could take the industrial approach and create a chemical safety plan. Since you generally aren’t worried about addressing spills and other accidents the plan would probably have 3 parts: 1) risk assessment, 2) controls, 3) monitoring.

The risk assessment is essentially what you are trying to do now. However, most of what you have gotten here is internet speculation so take it for what it’s worth. If you are concerned enough then your risk assessment conclusion may be that exposure is enough of a danger that you want to mitigate the risk.

For hazardous chemical exposure, “controls” are used to mitigate the risk.  Controls generally come in three forms: Administrative Controls, Engineering Controls, and Personal Protective Equipment (PPE).  Administrative controls are policies and SOPs that try to minimize who might have exposure. In the case of Avgas one might establish an SOP that passengers (e.g children and spouses) will not be within 50 feet of the aircraft during refueling. Engineering controls in this might be related to containing the fuel within the fuel system. As was just mentioned you should ensure that fuel isn’t leaking into the cabin. PPE is used for people who must have contact with hazardous material. It is things like gloves and respirators which shouldn’t be necessary for a kid riding in a plane but for those who are concerned about exposure while fueling you should decide what level of PPE is appropriate.

Monitoring in a case like this would probably be blood tests for lead. It would be best practice to have baseline tests so you can assess the exposure from the new activity. Some might feel a lot of blood tests might be invasive for a young child. A baseline for yourself might be useful and informative. If your test revealed no lead then you might be reasonably confident that a child would be safe in the GA environment.

Disclaimer: Once again, I am a chemist not an MD or OHS specialist. I have worked with hazardous chemicals and safety plans but I am not an expert on industrial hygiene in general or lead exposure in particular. Everything here should be treated as a general opinion and not as a recommendation for your specific situation.

[Marcopolo]

This may be a good stone to toss at both birds:

  Set the little one up with her own personal oxygen tank and cannula.  Chances are that she will be asleep shortly after take-off and shouldn't fuss much with the device before then.  Maybe have your wife sit with her to keep her busy til she nods off.  This should quell the concern fully on the oxygen depletion and definitely help with the reduction of if not the complete elimination of the lead ingestion / inhalation concern.  Just a thought!

[Marauder]

Anyone born in the 50s-70s will have been exposed to tons  of lead in car petrol (gas), can someone please point out to me as a 60s child how this has affected me, because to be honest i dont think it has.  

Are we worrying too much and moli kodling our children too much.  I personally think (as someone who ised to eat coal as a baby)  that unless you are bathing your child and  asking them to drink thenstuff then the lead factor is irrelevant.   With regards to  CO, it will affect you exactly the same as it will the children so you need to have a co alarm in the aircraft and if it goes off, get out FAST. 

Andrew

I think if you look at my grade school photo, you'd have to say it has had some impact.

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