From: B.Hamilton@irl.cri.nz (Bruce Hamilton)
Subject: Re: Ethyl - product details
Date: Aug 08 1997
Jim Davidson <email@example.com> wrote:
>Bruce Hamilton wrote:
>> >I don't believe that the toxicity of TEL was ever shown.
>> Nonsense, the parts of the FAQ that you carefully omitted *pointed* to
>> references on the subject , and I'll include some others also from the
>However, the toxicity of tetra ethyl lead is not the only relevant
>issue. When tetra ethyl led is burned in an engine, it forms lead
>oxide, which is not especially desirable but is also not especially
No. What is formed is a range of lead compounds and metallic lead
- depending on the combustion conditions. These compounds will
deposit in the combustion chamber, exhaust manifold, and exhaust
system and the engine soon ceases to function. As the FAQ notes,
right up until the 1950s it was common to find balls of metallic
lead rolling around inside the muffler because the scavenger
formulation was not optimum.
>However, ethylene dibromide is another typical additive, often
>used in combination with tetra ethyl lead which burns to form products
>which combine with lead oxide to form lead bromide. Lead bromide is
>toxic and volatile, and is one of the more troublesome of the compounds
>produced from the burning of leaded gasoline.
Either ethylene dichloride and/or ethylene dibromide can, and are,
used as scavengers usually around equal amounts of each, and it is
only in aviation gasoline where ethylene dibromide is solely specified
( to reduce the corrosion of aluminium ).
[Stuff about catalyst poisoning deleted, all in the FAQ, along which
other toxic emissions such as the organohalogens like dioxin ]
>> Review the early history of the manufacture of TEL in the early 1920s,
>> and a large number of workers were harmed, and some killed, before all
>> the appropriate precautions were taken.
>I find this argument entirely specious. Obviously when the manufacture
>of a new compound is developed, there can be some risk.
Well I'm stunned. I point to several reasonably-accessible
publications and, rather than read them and comment, you
instead " find this argument entirely specious "
Let's just review some of that "specious" history, most of
which filled the American Journal of Public Health during
the 1920s. This was not your typical new industrial chemical...
1910s - Alice Hamilton had shown that lead was an industrial toxin,
and a major hazard to exposed workers.
1921 - 9 December, Midgley discovers the anti-knock properties of TEL.
1922 - W.M.Clark, a chemistry professor wrote to the Assistant Surgeon
General at the Public Health Service warning of "a serious menace
to public health " and expresseed concern about the accumulation
of the toxin near roads " on busy thoroughfares it is highly
probable that the lead oxide dust will remain in the lower stratum".
There were already reports available to him about incidents involving
TEL in laboratories, although the researchers understood the
1922 The PHS couldn't afford to undertake an investigation into TEL, so
they wrote to Ethyl Corp. asking what research they had undertaken.
Thomas Midgley replied that no experiments had been performed.
1923 - 1st February, First gasoline containing TEL additive marketed.
1923 Ethyl Corp. realised they needed an "independant" assessment, so
they contracted the Bureau of Mines, however they specified that
no interim results should be made public by either party.
1924 July, Graham Edgar ( the inventor of Octane rating scale ) of Ethyl
wrote to the American Medical Association claiming that the BoM
research showed " that there is no danger of acquiring lead poisoning
through even prolonged exposure to exhaust gases of cars using Ethyl
fluid ", even though the preliminary report had not been released.
1924, 26 October Five workers die, thirty others show neurological
symptoms of organic lead poisoning, after an accident at the
Standard Oil Research Labs. Of the 49 workers and researchers in
the TEL plant, over 80% were severely poisoned ( went insane ).
The newspapers started to call TEL the " Looney Gas ".
As public health and labour officials ( Federal and State ) started
to investigate, they demonstrated, and Ethyl admitted " that it was
known that this gas had collected a previous toll of death and
1924 New York City, Philadelphia, and other municipalities and states
banned the sale of leaded gasoline.
1924 Midgley takes a prolonged vacation to cure himself of lead poisoning.
1925 Evidence is discovered that 2 people had previously died of
lead poisoning at GM Research at Dayton, and four more at the
DuPont site at Deeepwater. The New York Times discovered that there
were 300 cases of lead poisoning at Deepwater over the previous two
1925 The BoM report is issued after long, protracted negotiations which
had resulted in Ethyl Corp providing funds on the condition that they
had to approve all released reports. The released report was roundly
criticised by the public and the health officials as the claims of no
potential harm were obviously incorrect.
1925 Midgely blames all the incidents on careless workers. When questioned
by a reporter, he responds by washing his hands in some Ethyl fluid,
and states " I'm taking no chances whatever. Nor would I take any
chances doing that every day ". History doesn't record if he had
another extended vacation.
1925 20 May, the Surgeon General calls a conference of all the leading
participants in the TEL debate. Kettering, Midgley and the industry
supportors were on one side, and the opponents were lead by Alice
Hamilton, the country's foremost expert on lead poisoning, and
Yandell Henderson, of Yale University. After the conference, Ethyl
suspended all manufacture and distribution of TEL until an
"independent' investigation had been performed. Because Ethyl claimed
that TEL was essential for the economic well-being of the nation, the
investigation was only given a few months to examine and report.
1925, December. The report was predictable. they had examined 252 workers,
mostly garage attendents and chauffeurs, of which approx 20% were
controls, and another 20+% from inorganic lead dust industries. They
found no good grounds for prohibiting the use of TEL, but recommended
that more extensive government-funded studies be performed. Ethyl Corp.
quickly publicised the first, and no government-funded studies were
performed, with all susseqyuent studies were performed by scientists
funded by Ethyl Corp.
>appropriate precautions were taken, as they were for dozens of years
>during the period from the 1930s to the 1970s when leaded gasoline was
>commonplace, a vast quantity of tetra ethyl lead was produced without
>harm to large numbers of workers.
You are claiming that there were no further alkyl lead fatalities
or poisoning during that period, please provide the reference, as
I've got publications that clearly show otherwise.
Have you ever worked with pure TEL?, I have worked with 100ml
quatities. Let me describe what my employer considered appropriate.
First, a visit to the local occupational health specialist to check
my general state of health and take hair and blood samples for
background lead levels. These were repeated weekly, up until
one month after the last exposure, with a six monthly followup check.
First you strip, shower, and then you put on disposable cotton
undergarments. Next you put on heavy PVC trousers and a heavy
PVC jacket, buttoned and flap sealed at the back. Next follows
gumboots which are sealed inside the PVC trouser legs via ties.
Next is a positive pressure, filtered air supply hood with airline,
or a full BA system if high mobility is required. Then surgical
gloves followed by heavy PVC gauntlets that are sealed into the
sleeves. When you have finished, you pass through a high pressure
shower to thoroughly rinse the outer layers before starting to
change. At the completion of the work all clothing was disposed
of as heavy-metal contaminated.
Many of the above ( selection of healthy workers, daily monitoring,
rubber gloves, gas masks, and not wearing working clothes away from
the plant ) were already in place at the Baywater plant in the early
1920s before the poisoning.
Now, just in case you believe the above is an over-reaction, consider
the recent tragic case where an eminent researcher ( Karen E Wetterhahn )
spilt "one to a few drops" of dimethylmercury. The compound permeated
her latex gloves and was absorbed into her blood and she died. Details
can be found in C&EN 12 May 1997 p7,and C&EN 16 June 1997 p11,12.
Compounds like TEL,TML, and DMM are highly toxic, and the only reason
>Of course, the additives for unleaded gasoline have not been discussed.
>Safety issues involved in the production of these alternative additives
>as well as the pollution hazards of compounds they create when burned in
>an engine have been thoroughly underevaluated.
Well, if you had bothered reading some of the Gasoline FAQ, and
the references cited therein, you would know that the pollution
hazards of the compounds when burnt were extensively investigated
in the Auto/Oil programme, with the notable exception being the
potential for global carbonyl pollution - which is difficult and
The problems lie more with the pollution problems due to the
different water solubility of the oxygenates and the inhalation
hazards of the oxygenates in the fuel during refuelling, rather
than combustion properties. The major issue is whether they are
actually effective in reducing pollution.
>A person far more cynical than I would note that the patents on leaded
>gasoline had run out, as well as on the various lead-related gasoline
>additives, by the time the phase out of tetra ethyl lead was in full
What patents?. The TEL discovery was made on 9 Dec 1921, marketed on
1 February 1923, and TML was first marketed in 1960 by Standard Oil
Company of California. Give us the patent numbers, as a cynical
person like myself might assume you have no evidence.
>Might it have been an interested chemical company or two that
>wanted their new additives to have a protected and preferred place in
>the market who were the driving force behind the adoption of the
>unleaded gasoline laws?
Come on, the battle to retain lead in the early 1970s is well
documented. Associated Octel and Ethyl were unable to discover
a viable lead-tolerant exhaust catalyst, and there were no obvious
alternative octane enhancers that were viable, hence the octane
rating of the fuel dropped dramatically. For your claim to be
valid, there had to be an alternative available - there wasn't.
From: B.Hamilton@irl.cri.nz (Bruce Hamilton)
Subject: Re: Ethyl - product details
Date: Fri, 15 Aug 1997 20:08:43 GMT
Jim Davidson <firstname.lastname@example.org> wrote:
>Bruce Hamilton wrote:
>> Jim Davidson wrote:-
>>> When tetra ethyl led is burned in an engine, it forms lead
>>> oxide, which is not especially desirable but is also not
>>> especially toxic.
Note this claim is discussing "tetra ethyl lead ", not formulated
lead additive ( with scavengers ) - such as " Ethyl fluid ".
>> No. What is formed is a range of lead compounds and metallic lead
>> - depending on the combustion conditions. These compounds will
>> deposit in the combustion chamber, exhaust manifold, and exhaust
>> system and the engine soon ceases to function. As the FAQ notes,
>> right up until the 1950s it was common to find balls of metallic
>> lead rolling around inside the muffler because the scavenger
>> formulation was not optimum.
>One of those compounds is lead oxide.
Yes it is, and it is also non-volatile, and thus deposits in the
engine, manifold, and exhaust as above. That's the reason why TEL
was formulated with scavengers when added to gasoline. As far as
I'm aware, the investigation of scavengers immediately followed the
discovery of the anti-knock properties of TEL and by 1928 fuels
contained both ethylene dibromide and ethylene dichloride, thus
there was only a four year period when TEL could have been
marketed without scavengers. Your reference has yet to
be supplied that indicates lead oxide deposits in significant
quantities on the seat from leaded gasolines. One reference I have
states that lead halides deposit on the seat and oxides on the valve.
( " Exhaust Valve Recession with low-lead gasolines " Automotive
Engineering v.95 n.11 p.72-76 (1987).
>"Soon" seems to be an ill-defined term. I know of internal combustion
>engines that have operated for 40 years on leaded gasoline.
Strange, please cite your sources, as there was a maximum period
of four years when tetra ethyl lead ( the subject of your claim )
was used without scavengers. I suspect that you have now changed
your claim to "leaded gasoline" - which includes scavengers, and
thus supports my claim.
>> You are claiming that there were no further alkyl lead fatalities
>> or poisoning during that period, please provide the reference, as
>> I've got publications that clearly show otherwise.
>No, I made no such claim.
>Your documentation clearly shows, as you indicate, that with proper
>precautions, vast quantities of TEL were produced without harm to
>large numbers of workers.
Nowhere does my documentation claim that. TEL wasn't produced
worldwide " from the 1930s to the 1970s ... with proper
precautions " as you claim. There were hundreds of incidents
involving serious exposure of workers to TEL, including eight
fatalities in a single US incident more than thirty years after
the introduction of TEL ( " Tetraethyl Lead Poisoning Incident with
Eight Deaths " Am.Ind.Hyg.Assn.J. v.21 p515-517 (1960)). There were
incidents virtually every year, even though the known toxicity of
TEL had produced increasingly sophisticated production systems that
minimised the numbers of workers potentially exposed, and extensive
worker training was given.
Disproportionate numbers of workers were harmed by TEL - compared
to those handling and manufacturing of most other chemicals that
were also routinely available to the general public. The industry
expended great effort to minimise public concern and government
toxicological research during the period and yet, unlike asbestos,
the evidence of toxicity was comprehensive and compelling.
I finished my history of alkyl lead in 1928, but if you want to
learn about how the industry used several "scientific institutes",
including the " Mellon Institute " and the " Charles F.Kettering
Foundation and Kettering Laboratory of Applied Physiology " to
monopolise the public health research on TEL and lead hazards, then I
suggest you read " Hegemony through Science: Information Engineering
and Lead Toxicology, 1925-1965 " W.Graebner. Chapter 9 of
Dying for Work: Workers' Safety and Health in Twentieth-Century
America. Indiana University Press ISBN 0-253-31825-4 (1987).
TEL was not, and is not, a typical industrial chemical, and
is highly toxic. The production and distribution cost the lives
and health of many workers. Whilst the USA banned alkyl leads
because of their adverse effect on exhaust catalysts, other
countries ( such as the UK ) severely curtailed their use of alkyl
leads because of the adverse health effects of lead emissions,
especially on children.
TEL was required in the 1920s and 1930s to progress the development
of the internal combustion engine, and to efficiently produce
gasoline, and it served those purposes admirably well. However,
the dark side was the legacy of death and madness that persisted
right up until the 1970s, when public health officials finally
realised that the costs far outweighted the benefits, and that
society would benefit from the removal of alkyl leads.