BA's in-flight safety chief warns about toxic cabin fumes
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Except the smell *may* denote *what is conjectured to be* lethally toxic gas *that may* cause life-shattering or fatal injuries down the line
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Fume events "may" be triggered by a whole range of contaminants, not all of them toxic. But It's not in dispute that organophosphates, a chemical constituent of jet oil, are very harmful indeed and cause serious long-term health issues.
Last edited by ShotOne; 7th Dec 2016 at 18:28.
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Radiation dose-effects and hormesis
ShotOne, as far as “the implication that the radiation risk experienced by flight crew is very low” is concerned, my points are that (1) radiation risk is dependent upon specific variables: radiation type, dose, and dose-rate, and (2) below a certain threshold, radiation exposure has little risk or even a benign effect. It all depends on the numbers in each person’s case. Of course, if a pilot’s exposure exceeds that threshold, there would be an X probability of cancer.
The article and personal radiation-dose computation worksheet links provided in my earlier posts provide some perspective.
It is quite probable that a significant level (especially at high altitudes) of long-duration-UV exposure can cause skin cancer.
Paradoxically, sunlight is not the only significant variable. As my dermatologist tells me, skin melanoma often occurs without lifetime high exposure to sunlight. There are other factors involved such as genetic predisposition. Nonetheless, since I live in Florida, I try to minimize sun exposure.
Speaking more generally, the devil is in the details. Different (other) kinds of radiation (alpha, beta, gamma) have different biological effects. According to MIT News: “Because x-rays and gamma rays are less damaging to tissue than neutrons or alpha particles, a conversion factor is used to translate the rad or gray into other units such as rem (from Radiation Equivalent Man) or sieverts, which are used to express the biological impact.”
Another variable is dose rate. The same dose received within a small span of time has a greater negative effect than that received during a much longer duration.
There is growing evidence supporting radiation hormesis, the theory that low doses are harmless and may even have a beneficial effect by stimulating cell-repair mechanisms. Science sometimes takes a long time to change course, and challenging its conventional wisdom in a highly contradictory way means opposing its massive inertia, which is like that of a super tanker.
The scientific challenge is to define more precisely the boundary between the harmful and beneficial levels of both radiation dose and dose-rates, so that we can transition from the woolly generalization that all radiation is bad.
That can lead to use of low-level radiation to improve health in specific, scientifically proven contexts, and also reduce overextended radiation protection regulation that unnecessarily increases the cost of compliance for industry and government.
The current Linear No-Threshold (LNT) model underlying worldwide radiation protection standards is imprecise and clumsy. As Wikipedia (which provides an excellent overview of the LNT pros and cons) notes:
“The linear no-threshold model (LNT) is a model used in radiation protection to quantify radiation exposure and set regulatory limits. It assumes that the long term, biological damage caused by ionizing radiation (essentially the cancer risk) is directly proportional to the dose. This allows the summation by dosimeters of all radiation exposure, without taking into consideration dose levels or dose rates. In other words, radiation is always considered harmful with no safety threshold, and the sum of several very small exposures are considered to have the same effect as one larger exposure (response linearity).” https://en.wikipedia.org/wiki/Linear...el#Controversy
According to the World Nuclear Association:
“Some of the ultraviolet (UV) radiation from the sun is considered ionizing radiation, and provides a starting point in considering its effects. Sunlight UV is important in producing vitamin D in humans, but too much exposure produces sunburn and, potentially, skin cancer. Skin tissue is damaged, and that damage to DNA may not be repaired properly, so that over time, cancer develops and may be fatal. Adaptation from repeated low exposure can decrease vulnerability. . . . Our knowledge of the effects of shorter-wavelength ionizing radiation from atomic nuclei derives primarily from groups of people who have received high doses. The main difference from UV radiation is that beta, gamma and X-rays can penetrate the skin. The risk associated with large doses of this ionizing radiation is relatively well established. However, the effects, and any risks associated with doses under about 200 mSv [20 rem], are less obvious because of the large underlying incidence of cancer caused by other factors. Benefits of lower doses have long been recognised, though radiation protection standards assume that any dose of radiation, no matter how small, involves a possible risk to human health. However, available scientific evidence does not indicate any cancer risk or immediate effects at doses below 100 mSv [10 rem] per year. At low levels of exposure, the body's natural mechanisms usually repair radiation damage to DNA in cells soon after it occurs (see following section on low-level radiation). However, high-level irradiation overwhelms those repair mechanisms and is harmful. Dose rate is as important as overall dose.” Radiation | Nuclear Radiation | Ionizing Radiation | Health Effects - World Nuclear Association
More documentation about hormesis by other sources:
“In 1990, the ICRP [International Commission on Radiological Protection] (in its Publication 60) conceded that hormesis might exist but said that “the available data on hormesis are not sufficient to take them into account in radiological protection.” With the publication of a great deal of evidence on hormesis since 1990, the converse is now true, viz: that the ICRP would need to be very confident that radiation hormesis does not occur if it is going to recommend the assumption of LNT [the Linear No-Threshold concept].” --Dr. Donald J. Higson, Australasian Radiation Protection Society ICRP: Consultation view comment
“The conclusion of zero threshold dose for carcinogenic effects of radiation in the recent updated report on the atomic bomb survivor cancer mortality data appears to be unjustified and may be the result of the restrictive functional forms that were used to fit the data. Also, the shape of the dose-response observed in the recent update of atomic bomb survivor data is clearly non-linear with the significant reduction in cancer mortality rate in the dose range of 0.3 Gy to 0.7 Gy. This raises doubts about the LNT model and possibly shows evidence for the phenomenon of radiation hormesis when a correction is applied for a likely bias in the baseline cancer mortality rate. Though the use of radiation hormesis was proposed more than three decades ago as a method of reducing cancers, no prospective human cancer prevention studies have been conducted so far to determine its validity due to carcinogenic concerns based on the LNT model. . . . Low dose radiation may also be helpful in improving outcomes in cancer patients by cure of early stage cancers, as an adjuvant to standard radiation therapy to improve tumor control and reduce metastases, and to reduce the incidence of second cancers. Pilot clinical trials are needed to determine the effectiveness of low dose radiation in these applications. Success in such clinical trials can help to reduce the concerns regarding low dose radiation and enable the study of cancer prevention using radiation hormesis.”--”Linear No-Threshold Model VS. Radiation Hormesis,” by Mohan Doss, PhD, Associate Professor, Fox Chase Cancer Center, Philadelphia, PA https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3834742/
The article and personal radiation-dose computation worksheet links provided in my earlier posts provide some perspective.
It is quite probable that a significant level (especially at high altitudes) of long-duration-UV exposure can cause skin cancer.
Paradoxically, sunlight is not the only significant variable. As my dermatologist tells me, skin melanoma often occurs without lifetime high exposure to sunlight. There are other factors involved such as genetic predisposition. Nonetheless, since I live in Florida, I try to minimize sun exposure.
Speaking more generally, the devil is in the details. Different (other) kinds of radiation (alpha, beta, gamma) have different biological effects. According to MIT News: “Because x-rays and gamma rays are less damaging to tissue than neutrons or alpha particles, a conversion factor is used to translate the rad or gray into other units such as rem (from Radiation Equivalent Man) or sieverts, which are used to express the biological impact.”
Another variable is dose rate. The same dose received within a small span of time has a greater negative effect than that received during a much longer duration.
There is growing evidence supporting radiation hormesis, the theory that low doses are harmless and may even have a beneficial effect by stimulating cell-repair mechanisms. Science sometimes takes a long time to change course, and challenging its conventional wisdom in a highly contradictory way means opposing its massive inertia, which is like that of a super tanker.
The scientific challenge is to define more precisely the boundary between the harmful and beneficial levels of both radiation dose and dose-rates, so that we can transition from the woolly generalization that all radiation is bad.
That can lead to use of low-level radiation to improve health in specific, scientifically proven contexts, and also reduce overextended radiation protection regulation that unnecessarily increases the cost of compliance for industry and government.
The current Linear No-Threshold (LNT) model underlying worldwide radiation protection standards is imprecise and clumsy. As Wikipedia (which provides an excellent overview of the LNT pros and cons) notes:
“The linear no-threshold model (LNT) is a model used in radiation protection to quantify radiation exposure and set regulatory limits. It assumes that the long term, biological damage caused by ionizing radiation (essentially the cancer risk) is directly proportional to the dose. This allows the summation by dosimeters of all radiation exposure, without taking into consideration dose levels or dose rates. In other words, radiation is always considered harmful with no safety threshold, and the sum of several very small exposures are considered to have the same effect as one larger exposure (response linearity).” https://en.wikipedia.org/wiki/Linear...el#Controversy
According to the World Nuclear Association:
“Some of the ultraviolet (UV) radiation from the sun is considered ionizing radiation, and provides a starting point in considering its effects. Sunlight UV is important in producing vitamin D in humans, but too much exposure produces sunburn and, potentially, skin cancer. Skin tissue is damaged, and that damage to DNA may not be repaired properly, so that over time, cancer develops and may be fatal. Adaptation from repeated low exposure can decrease vulnerability. . . . Our knowledge of the effects of shorter-wavelength ionizing radiation from atomic nuclei derives primarily from groups of people who have received high doses. The main difference from UV radiation is that beta, gamma and X-rays can penetrate the skin. The risk associated with large doses of this ionizing radiation is relatively well established. However, the effects, and any risks associated with doses under about 200 mSv [20 rem], are less obvious because of the large underlying incidence of cancer caused by other factors. Benefits of lower doses have long been recognised, though radiation protection standards assume that any dose of radiation, no matter how small, involves a possible risk to human health. However, available scientific evidence does not indicate any cancer risk or immediate effects at doses below 100 mSv [10 rem] per year. At low levels of exposure, the body's natural mechanisms usually repair radiation damage to DNA in cells soon after it occurs (see following section on low-level radiation). However, high-level irradiation overwhelms those repair mechanisms and is harmful. Dose rate is as important as overall dose.” Radiation | Nuclear Radiation | Ionizing Radiation | Health Effects - World Nuclear Association
More documentation about hormesis by other sources:
“In 1990, the ICRP [International Commission on Radiological Protection] (in its Publication 60) conceded that hormesis might exist but said that “the available data on hormesis are not sufficient to take them into account in radiological protection.” With the publication of a great deal of evidence on hormesis since 1990, the converse is now true, viz: that the ICRP would need to be very confident that radiation hormesis does not occur if it is going to recommend the assumption of LNT [the Linear No-Threshold concept].” --Dr. Donald J. Higson, Australasian Radiation Protection Society ICRP: Consultation view comment
“The conclusion of zero threshold dose for carcinogenic effects of radiation in the recent updated report on the atomic bomb survivor cancer mortality data appears to be unjustified and may be the result of the restrictive functional forms that were used to fit the data. Also, the shape of the dose-response observed in the recent update of atomic bomb survivor data is clearly non-linear with the significant reduction in cancer mortality rate in the dose range of 0.3 Gy to 0.7 Gy. This raises doubts about the LNT model and possibly shows evidence for the phenomenon of radiation hormesis when a correction is applied for a likely bias in the baseline cancer mortality rate. Though the use of radiation hormesis was proposed more than three decades ago as a method of reducing cancers, no prospective human cancer prevention studies have been conducted so far to determine its validity due to carcinogenic concerns based on the LNT model. . . . Low dose radiation may also be helpful in improving outcomes in cancer patients by cure of early stage cancers, as an adjuvant to standard radiation therapy to improve tumor control and reduce metastases, and to reduce the incidence of second cancers. Pilot clinical trials are needed to determine the effectiveness of low dose radiation in these applications. Success in such clinical trials can help to reduce the concerns regarding low dose radiation and enable the study of cancer prevention using radiation hormesis.”--”Linear No-Threshold Model VS. Radiation Hormesis,” by Mohan Doss, PhD, Associate Professor, Fox Chase Cancer Center, Philadelphia, PA https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3834742/
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Ho ho! Except the smell denotes lethally toxic gas causing life-shattering or fatal injuries down the line Unfortunately it's only quite recently that such entries started getting much in the way of priority for treatment or rectification.
My point is, don't expect anyone else to protect you. Protect yourself by donning your masks. Or just keep your trap shut, your fingers crossed, and don't bother putting anything in the tech log!
Because by the time you land, it's too late!
This makes for an interesting read.
https://avherald.com/h?article=425f6a41&opt=0
https://avherald.com/h?article=425f6a41&opt=0
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Just to put the radiation bit to rest for good and all.
My dad's best friend (MRC) was the UK expert on radiation and industrial accidents.
He was always called out when it anything hit the fan.
Cosmic radiation has been steadily increasing over a number of years (mostly gamma), as the sun's activity has been steadily falling. (so much for global warming eh?)
When there's a CME (coronal mass ejection) the cosmic ray flux drops sharply in a FORBUSCH decrease.
This is a quote from Space weather, which is most informative, especially on why we get Aurorae (as is highly likely for christmas).
My dad's best friend (MRC) was the UK expert on radiation and industrial accidents.
He was always called out when it anything hit the fan.
Cosmic radiation has been steadily increasing over a number of years (mostly gamma), as the sun's activity has been steadily falling. (so much for global warming eh?)
When there's a CME (coronal mass ejection) the cosmic ray flux drops sharply in a FORBUSCH decrease.
This is a quote from Space weather, which is most informative, especially on why we get Aurorae (as is highly likely for christmas).
This plot displays radiation measurements not only in the stratosphere, but also at aviation altitudes. Dose rates are expessed as multiples of sea level. For instance, we see that boarding a plane that flies at 25,000 feet exposes passengers to dose rates ~10x higher than sea level. At 40,000 feet, the multiplier is closer to 50x. These measurements are made by our usual cosmic ray payload as it passes through aviation altitudes en route to the stratosphere over California.
What is this all about? Approximately once a week, Spaceweather.com and the students of Earth to Sky Calculus fly space weather balloons to the stratosphere over California. These balloons are equipped with radiation sensors that detect cosmic rays, a surprisingly "down to Earth" form of space weather. Cosmic rays can seed clouds, trigger lightning, and penetrate commercial airplanes. Furthermore, there are studies ( #1, #2, #3, #4) linking cosmic rays with cardiac arrhythmias and sudden cardiac death in the general population. Our latest measurements show that cosmic rays are intensifying, with an increase of more than 12% since 2015:
Why are cosmic rays intensifying? The main reason is the sun. Solar storm clouds such as coronal mass ejections (CMEs) sweep aside cosmic rays when they pass by Earth. During Solar Maximum, CMEs are abundant and cosmic rays are held at bay. Now, however, the solar cycle is swinging toward Solar Minimum, allowing cosmic rays to return. Another reason could be the weakening of Earth's magnetic field, which helps protect us from deep-space radiation.
The radiation sensors onboard our helium balloons detect X-rays and gamma-rays in the energy range 10 keV to 20 MeV. These energies span the range of medical X-ray machines and airport security scanners.
The data points in the graph above correspond to the peak of the Reneger-Pfotzer maximum, which lies about 67,000 feet above central California. When cosmic rays crash into Earth's atmosphere, they produce a spray of secondary particles that is most intense at the entrance to the stratosphere. Physicists Eric Reneger and Georg Pfotzer discovered the maximum using balloons in the 1930s and it is what we are measuring today.
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This subject has already been covered here ad nauseam.
http://www.pprune.org/medical-health...ion-doses.html
AMS Gatwick, Airline and Airport Aviation Medical Examiners
However you have to look no further than concorde for all the info you might ever need, and/or if paranoia is really taking hold.
The supersonic aircraft with the greatest range of all, being able to outfly military aircraft.
The civil aircraft with the greatest radiation exposure profile, because of altitude to reduce drag, c/w highest maximum cruise altitude (60,000ft).
One of the most advanced SST aircraft with the longest unbroken service period (27 years), the only other being TU144 which was a FAIL.
The only civil aircraft fitted with a dosimeter as standard.
This unit was developed and calibrated with the help of Aldermaston nuclear weapons AWRE lab.
You can read about it here:-
At 60 000ft, the a/c internal usual dose rate is usually around 1mR/h.
For x-rays and gamma rays, 1 rad = 1 rem = 10 mSv
For neutrons, 1 rad = 5 to 20 rem (depending on energy level) = 50-200 mSv
TBQH there are places in the UK, which have almost as high background radiation levels at ground level 24/7/365 than you would get in a/c at FL30. (eg. chiltern hills around High Wycombe).
"nuff said?
http://www.pprune.org/medical-health...ion-doses.html
AMS Gatwick, Airline and Airport Aviation Medical Examiners
However you have to look no further than concorde for all the info you might ever need, and/or if paranoia is really taking hold.
The supersonic aircraft with the greatest range of all, being able to outfly military aircraft.
The civil aircraft with the greatest radiation exposure profile, because of altitude to reduce drag, c/w highest maximum cruise altitude (60,000ft).
One of the most advanced SST aircraft with the longest unbroken service period (27 years), the only other being TU144 which was a FAIL.
The only civil aircraft fitted with a dosimeter as standard.
This unit was developed and calibrated with the help of Aldermaston nuclear weapons AWRE lab.
You can read about it here:-
At 60 000ft, the a/c internal usual dose rate is usually around 1mR/h.
For x-rays and gamma rays, 1 rad = 1 rem = 10 mSv
For neutrons, 1 rad = 5 to 20 rem (depending on energy level) = 50-200 mSv
TBQH there are places in the UK, which have almost as high background radiation levels at ground level 24/7/365 than you would get in a/c at FL30. (eg. chiltern hills around High Wycombe).
"nuff said?
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It doens't help when the union medical expert doesn't believe in it..
Perhaps because they've been trained to believe evidence and carefully tested theories rather than anecdotes and 3rd-hand tales?
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Nemrytter you do write a lot of sense but you are UK based and therefore have no excuses to ignore the disgrace over the Organo Phosphate decades of denial, spin and lies for the farming community.
Did the methodologies you describe equally apply there too? Or that mild sleeping assistance, Thalidomide?
The record is not perfect and vested interests have always been deeply involved in these previous tragedies.
Rob
Did the methodologies you describe equally apply there too? Or that mild sleeping assistance, Thalidomide?
The record is not perfect and vested interests have always been deeply involved in these previous tragedies.
Rob
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Just on the topic of fume events...
British airlines to be sued because 'planes contain toxic air' | The Independent
British airlines to be sued because 'planes contain toxic air' | The Independent
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Nemrytter you do write a lot of sense but you are UK based and therefore have no excuses to ignore the disgrace over the Organo Phosphate decades of denial, spin and lies for the farming community.
Did the methodologies you describe equally apply there too? Or that mild sleeping assistance, Thalidomide?
The record is not perfect and vested interests have always been deeply involved in these previous tragedies.
Rob
Did the methodologies you describe equally apply there too? Or that mild sleeping assistance, Thalidomide?
The record is not perfect and vested interests have always been deeply involved in these previous tragedies.
Rob
We know that certain substances can, in great enough doses, cause harm. We know that those substances can be present in aircraft cabin air. What we don't know is how often these substances are present, and whether they are present in amounts great enough to cause any harm. Current research based upon interviewing flight crews suggests that they may, on rare occasions, be present in great enough doses. Current research based upon actually measuring the concentrations of these substances suggests that they are not present in such doses.
Obviously there's more research to be done, and is being done right now by many different groups of researchers (some independent, others not). Quite frankly the hyperbolic comments by many (not just here) are silliness. Websites with skull-and-crossbones, talk of conspiracies and a general hyperbolic exaggeration of the slightest fume incident don't help. In fact, I'd say that this type of stuff hinders a proper understanding of fume events and how they may cause health issues. I was at a meeting a few weeks ago where we had one crew representative who was shouting that "these aircraft are killing us, we will all be dead within a decade". That talk is deeply unhelpful.
Yes, I know that's easy to say and harder to do when you believe you're being exposed to these fumes but, unfortunately, that's life. Screaming about it and presenting some hideously distorted version of events makes things harder for everyone. Again, that goes both ways. Figuring out the facts will be done, but it can't be done instantly and it does require solid facts and evidence - something proponents of 'aerotoxic' are a little short of at this time.
(edit) The news article above is a perfect example of this: Rather than trying to get expert opinion they try to push something through the courts, knowing there's not enough evidence available. Deeply unhelpful.
It is rather frustrating when suffering these toxic effects to be told for decades that one day the truth will out. The problem lies in the fact that apart from occasional extreme occurrences the day to day accumulations of low exposure take years before symptoms show.
Those of us who regularly fly or flew some types know well the odour associated with oil fumes. Back in the 90s we were unaware of the cumulative toxic nature of these fumes.
It is strange that these toxic substances are still being inflicted on passengers and crew. One day no doubt we will look back and wonder how it was allowed to happen, over the years this has often been the case in industrial poisoning.
Those of us who regularly fly or flew some types know well the odour associated with oil fumes. Back in the 90s we were unaware of the cumulative toxic nature of these fumes.
It is strange that these toxic substances are still being inflicted on passengers and crew. One day no doubt we will look back and wonder how it was allowed to happen, over the years this has often been the case in industrial poisoning.