Transcript Slide 1

MTBE
As a fuel additive, is it more harmful than helpful?
Slides produced by:
Robert Bennigsdorf
What is MTBE?
Technically speaking, it’s “Methyl Tert-Butyl Ether”
Visually it is:
Q: But what is it used for?
A: As a fuel additive.
PURPOSE OF MTBE:
When gasoline is burned, one possible byproduct is carbon monoxide
CO =
One way to eliminate the production of carbon monoxide is to add
an oxidizing agent to turn the carbon monoxide into carbon dioxide.
CO + Oxidizer
CO2
But was MTBE always the oxidizing agent used?
Answer: NO!
Fuel used to have lead in it (thus the reason why we buy unleaded
fuel now).
The lead used to act as the oxidizing agent until the 1970s when
the adverse health effects from lead were fully realized and then
new additives had to replace it.
Currently we use a combination of alcohols, ethers and the
highly toxic and cancer-causing benzene.
The ether that we use is known as MTBE.
THE PROBLEM WITH MTBE
Simply put, the problem with MTBE is that it is way too soluble in water.
Approximately 50,000 mg per liter can be dissolved.
When gasoline enters the environment, the solubility of MTBE is far
greater than that of gasoline or the other additives, this creates the
current problem where MTBE quickly enters the ground water and
travels it is wherever it goes – even to the water supply.
How does MTBE enter the environment?
MTBE (through gasoline) can enter the environment
through 4 main ways:
1. Through leaking underground tanks
Many of the tanks that store gasoline at factories or gas stations
are old and in need of repairs or replacement. In a study from 2000
from the USGAO showed that 29% of USTs were in need of repairs
(accounting for 14,500 leaks). 1
2. Spills
Gasoline spills from filling accidents and car accidents
3. Watercrafts
Watercraft engines routinely release some unused fuel into the oceans.
4. Vaporization
Every time you fill up with gas, some escapes
as vapors, with MTBE.
Moyer, Ellen. MTBE Remediation Handbook, Amherst: Amherst
Scientific Publishers, 2003. pg 7.
WHAT HAPPENS ONCE THE MTBE GETS INTO THE
WATER SUPPLY?
Honestly….it stays there.
MTBE is extremely difficult (and therefore extremely expensive) to clean
up. Reason: it is just too darn soluble in water!
California Data of MTBE contamination is:
0.8% of drinking water supply contained detectable
levels of MTBE
95% contained no MTBE, of the remaining 5%:
73% were below the level the state
recommended. 2
2. Moyer pg 68
Then why all the attention?
In 1997 the city of Santa Monica did reach the level of contamination
had was forced to shut down half of it water wells.
This resulted in a 75% loss of the groundwater supply for the city
and $3 million had to be spent bringing in bottled water.3
-WELL, what actually can MTBE do to you if its so bad?
Honestly…nothing that we can really say.
3. Jacobs, James. MTBE effects on soil and groundwater
resources. London: Lewis Publishers, 2000. pg 11.
HAS ANY HUMAN EVER DIED FROM MTBE?
Not that we know of
HAS ANY HUMAN EVER GOTTEN CANCER FROM MTBE?
Not that we know of
Can MTBE actually cause cancer in humans?
Not that we know of
IS MTBE CLASSIFIED AS A CARCINOGENE?
No
According to a 1998 publication from the California State Senate:
“There are studies in rodents showing MTBE has potentially carcinogenic
properties in high doses. Exposure was associated with a dose-related increase in
leukemia and lymphomas in female rats and an increase in benign testicular
tumors in male rats. There are two studies of the potential carcinogenicity of MTBE
after inhalation exposure. One study showed exposure caused an increase in the
incidence of kidney tumors, both malignant and benign, as well as testicular
tumors in male rats. The other showed significant increases in malignant liver
tumors in male mice and non-malignant liver tumors in female mice.”4
But how high is this “high dose” mentioned above?
It is 1,000mg per 1kg body mass for 104 days.5
Do we need to worry about this concentration being present
right now?
Not really, since we can smell MTBE at 20 ppb and
taste it at 40 ppb.
4. Does California need MTBE? California State Senate publication 98-4/A May
1998.
5. Jacobs pg 26.
Did these studies have any effects?
Yes they did.
Former Governor Gray Davis encouraged the phasing out of MTBE by
December 31, 2001
Furthermore the US government has begun investigation the use of
alternative fuel additives that can do the same thing.
What else can do it?
Well, I mentioned that there were three things that could be
fuel additives:
Ethers
Benzene
Alcohols
THE WONDERFUL WORLD OF ETHANOL
Ethanol is a wonderful compound with many great properties…..
Such as also being an oxidizing agent
Ethanol can also oxidize carbon monoxide into carbon dioxide,
though obviously not as well since we’d be using ethanol instead of
MTBE this whole time, which really would make this presentation
unnecessary since there is no danger of ethanol invading our water
supply except for maybe more homeless people drinking out of
water fountains and for the nonexistence bottle water companies…
So what is the big problem with using ethanol??
$$$$$$
If we were to switch over to only ethanol and no MTBE, gasoline
would cost a WHOLE BUNCH MORE.
You want proof? California already requires a high
percentage of ethanol that other states (Davis….) and it is
reflected in gas prices:
The latest data from CNN.com showed national average for
regular gas was $1.98 gallon, whereas California was second
highest with $2.25 (only hawaii higher where they have like 1000
miles of ocean to get it to there).
So we can see that if we were to change completely to ethanol we would
decrease the amount of MTBE in the groundwater, but we’d also decrease the
amount of money in our wallets.
Is Congress then going to stop pushing ethanol?
Unlikely, see, ethanol can come from corn, which is grown in
the good old US of A (think Iowa and Nebraska, not much there
but corn, lots and lots of corn…)
In fact, I got from the library a 195 page transcript of a hearing from July 2,
2003 from the committee on government reform of the US House of
Representatives titled: “California Gasoline Markets: from MTBE to
ethanol”
Side note:
My least favorite part of the transcript was when the discussion of ethanol’s
higher vapor pressure would cause a decrease in the volume of gasoline
actually produced versus MTBE. This would cause an increase in cost per
gallon of 3 to 6 cents per gallon just from that loss. This would equal $33 to
$66 million per month from California drivers to ethanol producers in Iowa
and Nebraska
So, it is a choice between the environment and money?
Yes and no.
To suggest that MTBE is horrible for the environment and
that ethanol has no negative affects is wrong.
Ethanol can also negatively affect the environment by not
working as well as MTBE and thus allowing more
poisonous carbon monoxide into the atmosphere.
There is also one more downside to ethanol, and that is the
problem of energy.
There exists a good argument against the move to ethanol, and this one
of the energy required to refine ethanol.
I said earlier that ethanol can be refined from corn, though I never
said how this is done. The answer, as in all things, energy.
The energy required to refine the ethanol from corn is actually greater
than the energy that the ethanol will ultimately produce when burned, and
this difference is much greater.
The problem lies in where this energy comes from…fossil fuels of
course!!
This doesn’t really help the environment to burn fossil fuels in order to keep
the groundwater clean, or so goes the argument.
So what are we to do? Clean Air or Clean Water?
This is the ultimate question, and one that is not easily answered, the
only help that I will leave is a quote found in the front of one of the
books on MTBE:
“The significant problems we face
cannot be solved at the same
level of thinking we were at when
we created them.”
-Albert Einstein