MTBE is not terribly toxic

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There was that thread in the off topic section on ethanol fuels, but I just wanted to address one claim that MTBE is toxic. Certainly it is toxic, but no more so than gasoline - and it would require breathing in the vapors deeply. It's actually used in medical treatments. The small quantities that ended up in groundwater weren't really much of a health concern.

The big deal with MTBE was that when it got into the environment, a very tiny amount in water would create a foul, turpentine-like odor/taste.

Quote:
https://archive.epa.gov/mtbe/web/html/water.html

Is MTBE harmful to humans?

The majority of the human health-related research conducted to date on MTBE has focused on effects associated with the inhalation of the chemical. When research animals inhaled high concentrations of MTBE, some developed cancers or experienced other non-cancerous health effects To date, independent expert review groups who have assessed MTBE inhalation health risks e.g., Interagency Assessment of Oxygenated Fuels) have not concluded that the use of MTBE-oxygenated gasoline poses an imminent threat to public health. However, researchers have limited data about what the health effects may be if a person swallows (ingests) MTBE. EPA's Office of Water has concluded that available data are not adequate to estimate potential health risks of MTBE at low exposure levels in drinking water but that the data support the conclusion that MTBE is a potential human carcinogen at high doses. Recent work by EPA and other researchers is expected to help determine more precisely the potential for health effects from MTBE in drinking water.

EPA reviewed available health effects information on MTBE in its 1997 Drinking Water Advisory guidance and decided that there was insufficient information available to allow EPA to establish quantitative estimates for health risks and as such would not set health advisory limits. The drinking water advisory document indicates that there is little likelihood that MTBE in drinking water will cause adverse health effects at concentrations between 20 and 40 ppb or below.

How do I know if I have MTBE in my water?

It is possible your water would taste and/or smell like turpentine if MTBE is present at levels around or above 20-40 ppb (some people may detect it at even lower levels).
 
I find It near impossible to believe anything a politician or government employees says.
 
Originally Posted By: CT8
I find It near impossible to believe anything a politician or government employees says.

There's plenty of independent research on this. The biggest obstacle to using MTBE is that small amounts in H2O give drinking water a highly objectionable taste and that once it started leaking it got into water at an extremely fast rate.

It had one advantage that was extremely valuable, which was that it could be transported through existing pipelines without causing excessive corrosion.
 
Originally Posted By: y_p_w
Originally Posted By: CT8
I find It near impossible to believe anything a politician or government employees says.

There's plenty of independent research on this. The biggest obstacle to using MTBE is that small amounts in H2O give drinking water a highly objectionable taste and that once it started leaking it got into water at an extremely fast rate.

It had one advantage that was extremely valuable, which was that it could be transported through existing pipelines without causing excessive corrosion.


+1. Not sure how CT8 could reject objective results from analytical chemical assessments, but I'm sure there will be a good answer to support the agenda.

I'm no fan of either, but I am a fan of not smelling stinky cars in the winter mornings.
 
Originally Posted By: JHZR2
Originally Posted By: y_p_w
Originally Posted By: CT8
I find It near impossible to believe anything a politician or government employees says.

There's plenty of independent research on this. The biggest obstacle to using MTBE is that small amounts in H2O give drinking water a highly objectionable taste and that once it started leaking it got into water at an extremely fast rate.

It had one advantage that was extremely valuable, which was that it could be transported through existing pipelines without causing excessive corrosion.


+1. Not sure how CT8 could reject objective results from analytical chemical assessments, but I'm sure there will be a good answer to support the agenda.

I'm no fan of either, but I am a fan of not smelling stinky cars in the winter mornings.

MTBE isn't being used any more because of the most obvious effect on the taste when it gets into water supplies. I guess it's not great that it might do that, but sometimes tanks leak, pipelines leak, or a tanker overturns and spills. Certainly it's proven toxic in large quantities, but there's not much evidence that small amounts carry a lot of health risks.

If fuel distributors could go back to using MTBE they've do it immediately. I did hear about an ethanol alternative. I think it's butanol, which is supposed to have fewer drawbacks. I heard it could be shipped blended with gasoline in pipelines.
 
MTBE is also slower to degrade when it DOES get into the environment.

Hands up everyone in the thread who wants their water to taste like turpentine, even if it's minimal risk ?
If it did, what would you expect to be done about it ?

Hands up who doesn't care if their neighbour's water tastes like turpentine...after all it's not going to hurt them ?
 
"EPA's Office of Water has concluded that available data are not adequate to estimate potential health risks of MTBE at low exposure levels in drinking water..."
I don't see anything that says it is not toxic at low exposure levels, it's says they don't have enough info to judge that yet. Seems to me that this is a case of the OPer reading this to mean what he wanted it to.

Some folks in my town got free connections to town water due to their wells being contaminated and it was quite a job to extend the network to them. I'm not sure exactly how things got paid for in the end, but some of the money came from the town and it would have been nice for that to go to schools or roads instead. I felt for the residents affected and I know one of them died from cancer not long after the whole debacle...yes, I know it is unlikely that it was related to MTBE, but I'm sure his family will always wonder.
 
Originally Posted By: Shannow
MTBE is also slower to degrade when it DOES get into the environment.

Hands up everyone in the thread who wants their water to taste like turpentine, even if it's minimal risk ?
If it did, what would you expect to be done about it ?

Hands up who doesn't care if their neighbour's water tastes like turpentine...after all it's not going to hurt them ?

I personally have no problem with either ethanol or MTBE being used. Perhaps I should have stated that it's not generally considered to be more toxic than gasoline. However, there seem to be assumptions that MTBE was mostly discontinued because of its toxicity, while the primary reason was that leakage makes drinking water unpalatable. Quite a few people buy bottle water for its taste compared to local tap water, so of course the taste of water is an important concern.
 
There is a difference between knowing something is terribly toxic and not knowing enough to determine that is the case. If you actually read the information on MTBE, it falls in the latter - they don't know enough to say it is or isn't at low level of exposure. This is NOT the same as saying it isn't toxic. And it is toxic at higher levels, but to get that level of ingestion you'd be way beyond the amount that tastes bad.

Yes, MTBE was banned because of its solubility in groundwater and its effects on taste and odor. The fact of the matter is that if MTBE was in the groundwater, that meant gasoline with MTBE was leaking into the groundwater as well. Neither is good news, but MTBE travels further faster than gasoline making it less easily contained. On top of that, it is harder to remove. Not a good recipe...
 
Originally Posted By: y_p_w
I personally have no problem with either ethanol or MTBE being used. Perhaps I should have stated that it's not generally considered to be more toxic than gasoline. However, there seem to be assumptions that MTBE was mostly discontinued because of its toxicity, while the primary reason was that leakage makes drinking water unpalatable. Quite a few people buy bottle water for its taste compared to local tap water, so of course the taste of water is an important concern.


Now that we've widespread catalytic converter use, electronic control systems and the like, why are we playing with oxygenates at all ?

Oxygenates were there to reduce photochemical smog...not a problem with cats and closed loop, not like the bad old days.

We can get Octane without TEL with modern refining.

So why either Ethanol or MTBE ?

As to why it was phased out for toxicity...here's what Harvard say...

http://www.law.harvard.edu/students/orgs/elr/vol28_2/mcgarity.pdf

Oh, a failure due to legislators picking winners, and the law of Unintended consequences that arises from it.
 
Originally Posted By: Shannow
Originally Posted By: y_p_w
I personally have no problem with either ethanol or MTBE being used. Perhaps I should have stated that it's not generally considered to be more toxic than gasoline. However, there seem to be assumptions that MTBE was mostly discontinued because of its toxicity, while the primary reason was that leakage makes drinking water unpalatable. Quite a few people buy bottle water for its taste compared to local tap water, so of course the taste of water is an important concern.


Now that we've widespread catalytic converter use, electronic control systems and the like, why are we playing with oxygenates at all ?

Oxygenates were there to reduce photochemical smog...not a problem with cats and closed loop, not like the bad old days.

We can get Octane without TEL with modern refining.

So why either Ethanol or MTBE ?

As to why it was phased out for toxicity...here's what Harvard say...

http://www.law.harvard.edu/students/orgs/elr/vol28_2/mcgarity.pdf

Oh, a failure due to legislators picking winners, and the law of Unintended consequences that arises from it.

Still - the primary reason for an effective phase out of MTBE was how leaks affected water supplies. Any concerns about the toxicity in small levels that would appear from water contamination is speculative at this point.

Right now the cost of oxygenates is less than for gasoline, so obviously that's a plus considering the high blending octane. Refining only gets you so far, and it's not really refining per se that produces higher octane fuel streams but a chemical process that has limits. Throw in the increased demand for higher octane fuels, and it make a lot of sense to use ethanol simply for that.
 
Originally Posted By: y_p_w
Right now the cost of oxygenates is less than for gasoline, so obviously that's a plus considering the high blending octane. Refining only gets you so far, and it's not really refining per se that produces higher octane fuel streams but a chemical process that has limits. Throw in the increased demand for higher octane fuels, and it make a lot of sense to use ethanol simply for that.


OK a list of statements that need some backing...links would be good.

Honestly, you state that we can't get the Octane without oxygenates ?

I can get 98 and 100RON unleaded, ethanol free...how is that possible ?

by that further chemical process you are referring to cracking right ?

As to cheaper...is that Ethanol, which I can't see being cheaper in Oz or the US coming from grains, unless it's subsidised (removal of transport taxes from the Ethanol component is still a subsidy).

MTBE is made from Butane (from NG and Crude processing), and Methanol (manufactured from Crude)...so how can it be cheaper than regular hydrocarbons from crude ?
 
There is a depot near me that had a pipeline leak for years with the MTBE contaminating the ground water. The person who was complaining was some sort of a lawyer and their house sat on top of the leaking area. A lawsuit was filed and after about 15 years Shell and Phillips had to pay out millions in damages, they also extended the city water out to the rural areas at cost of more millions. Ironically soon after the suit was settled the lawyer's house burnt to the ground with the lawyer in it.....
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Originally Posted By: Shannow
Originally Posted By: y_p_w
Right now the cost of oxygenates is less than for gasoline, so obviously that's a plus considering the high blending octane. Refining only gets you so far, and it's not really refining per se that produces higher octane fuel streams but a chemical process that has limits. Throw in the increased demand for higher octane fuels, and it make a lot of sense to use ethanol simply for that.


OK a list of statements that need some backing...links would be good.

Honestly, you state that we can't get the Octane without oxygenates ?

I can get 98 and 100RON unleaded, ethanol free...how is that possible ?

by that further chemical process you are referring to cracking right ?

As to cheaper...is that Ethanol, which I can't see being cheaper in Oz or the US coming from grains, unless it's subsidised (removal of transport taxes from the Ethanol component is still a subsidy).

MTBE is made from Butane (from NG and Crude processing), and Methanol (manufactured from Crude)...so how can it be cheaper than regular hydrocarbons from crude ?

Well - the spot price of MTBE (which is still legal in some parts of the United States) is less than gasoline. It's comparable to ethanol, and has quite a few advantages such as up to 15% considered acceptable, which would make the price of the finished fuel cheaper and the ability to transport through pipelines. The spot price of ethanol in the United States is still less than gasoline, and it's not because of subsidies. There hasn't been a subsidy on corn ethanol in years. Page 10 has the spot price in March 2017 of MTBE at about $1.55/gallon.

https://www.opisnet.com/images/ProductSamples/OPISnewsletter-sample.pdf

If it would be possible to make as much 93 AKI octane fuel out of all the gasoline fractions of crude oil without oxygenates, you don't think that oil companies would be trying to do that? Of course it's possible to make 93 AKI octane fuel without ethanol, MTBE, or methanol - solely with distillation and no chemical processes. However, what do you do with the leftover output that isn't acceptable for anything more than camp fuel? It's probably possible to turn lower octane fuel streams into higher octane fuel using chemical processes, but my understanding is that it takes additional energy and results in a loss of fuel volume. The various blending exercises done by oil companies are to meet all the regulatory requirements and to sell as much of what they have without having unsaleable products. Obviously oxygenates with a high blending octane rating are extremely desirable because they cost less while boosting the octane rating.
 
I don't know what you would call an EPA mandate to use ethanol if it's not a subsidy. I do believe some blenders still get a kickback for using ethanol. At least in tradeable carbon credits if nothing else. Not to mention the fact FI engines don't need oxygenated fuel.


Federal Subsidies for Corn Ethanol and Other Corn-Based Biofuels
Quote:
Subsidies for corn ethanol also litter the tax code – including tax breaks for biodiesel and blender pumps which dispense higher blends of ethanol– in addition to Department of Energy programs and other subsidies scattered throughout the federal government such as the Renewable Fuel Standard (RFS) mandate for the use of corn ethanol administered by the Environmental Protection Agency (EPA). Late last year, Congress passed a tax extenders package that once again extended the Alternative Fuel Vehicle Refueling Property Credit, which provides a 30 percent tax break for gasoline stations or other facilities installing biodiesel or 85 percent ethanol (E85) blender pumps. The credit received a one-year retroactive extension for calendar year 2014. While Congress has signaled an intent to take a different approach than routinely extending this package of tax breaks each year, time will tell if any wasteful tax credits are ended later this year.
 
Originally Posted By: SHOZ
I don't know what you would call an EPA mandate to use ethanol if it's not a subsidy. I do believe some blenders still get a kickback for using ethanol. At least in tradeable carbon credits if nothing else. Not to mention the fact FI engines don't need oxygenated fuel.


Federal Subsidies for Corn Ethanol and Other Corn-Based Biofuels
Quote:
Subsidies for corn ethanol also litter the tax code – including tax breaks for biodiesel and blender pumps which dispense higher blends of ethanol– in addition to Department of Energy programs and other subsidies scattered throughout the federal government such as the Renewable Fuel Standard (RFS) mandate for the use of corn ethanol administered by the Environmental Protection Agency (EPA). Late last year, Congress passed a tax extenders package that once again extended the Alternative Fuel Vehicle Refueling Property Credit, which provides a 30 percent tax break for gasoline stations or other facilities installing biodiesel or 85 percent ethanol (E85) blender pumps. The credit received a one-year retroactive extension for calendar year 2014. While Congress has signaled an intent to take a different approach than routinely extending this package of tax breaks each year, time will tell if any wasteful tax credits are ended later this year.

Your quotes have little to do with the common use of E10.

As a practical matter of cost and availability, the use of E10 makes a ton of sense from a cost and as an octane booster. I mean - a fuel that's cheaper by volume AND it's an octane booster? It shouldn't be a surprise that it's common and would be simply on the basis of it's effect on octane rating.
 
Originally Posted By: y_p_w
However, what do you do with the leftover output that isn't acceptable for anything more than camp fuel?


You still aren't bringing much more than opinion and conjecture...

By "chemical process", you ARE referring to cracking aren't you...something that's done at nearly every refinery to fine tune the yield(s).

You seem to have the mistaken impression that you refine oil for gasoline then have to dispose of the rest...

Here's the "natural yield" on the left, versus the typical demand on the right of a couple of crudes.



See the demand for all those "waste" streams ?

And that's before cracking, that's just distillation.

I've been trying to find anything that supports your assertion that oxygenates are essential for modern fuel production...but can't.

But surely you can bring something to the table.
 
Originally Posted By: Shannow
Originally Posted By: y_p_w
However, what do you do with the leftover output that isn't acceptable for anything more than camp fuel?


You still aren't bringing much more than opinion and conjecture...

By "chemical process", you ARE referring to cracking aren't you...something that's done at nearly every refinery to fine tune the yield(s).

You seem to have the mistaken impression that you refine oil for gasoline then have to dispose of the rest...

Here's the "natural yield" on the left, versus the typical demand on the right of a couple of crudes.



See the demand for all those "waste" streams ?

And that's before cracking, that's just distillation.

I've been trying to find anything that supports your assertion that oxygenates are essential for modern fuel production...but can't.

But surely you can bring something to the table.

Nice strawman. I wasn't referring to the other fractions that are useful as jet fuel and various industrial products like asphalt. I'm talking about the combination of all the suitable gasoline blend stocks. After distillation and cracking, if the output is combined it's still not going to be higher than maybe 89 AKI octane without some energy/cost-intensive process.

It may not have been that critical when the vast majority of vehicle operated just fine on regular unleaded, but these days even small cars are tuned to require higher octane rated fuel in order to meet fuel economy standards. Add to that many high performance vehicles tuned for 91 (or even 93) AKI and it's really hard to meet that requirement. Back around 2001 the standard "premium fuel" in California started transitioning from 92 to 91, in part due to the demand for premium in California with a higher proportion of high performance and luxury cars.

Using some sort of oxygenate is the most cost effective means to improve the octane rating of fuels. That's not conjecture. The use of ethanol is already built into the commodity market, such as with RBOB.
 
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