BP Gulf oil blowoutstill gushes chemicals in the air, in the water and on the ground. Benzene, Hydrogen Sulfide, Methyl Chloride, Sulfur Dioxide and Cyclohexane are the dangerous chemicals to watch out for. Chris Landau (geologist/meteorologist)
Understanding which petroleum gases will stay near the ground and which will be carried up to mix with our rain clouds.
Air has a density of about 1.2 kg per cubic meter (kg.m-3) at 60 degrees F.
Vapor Pressure is the tendency of that liquid or solid to evaporate to a gaseous form. A substance with a high vapor pressure at normal temperatures is often called volatile. Liquids start to change to gaseous form as soon as they change from solid to liquid. Some like carbon dioxide sublimate and go directly to a gas without first becoming a liquid. Naphthalene, one of the heavier fractions of crude oil, also begins to change to a gas from a solid, but does have a liquid phase too.
The atmospheric pressure boiling point of a liquid (also known as the normal boiling point of that compound) is the temperature at which the vapor pressure of that compound equals the ambient atmospheric pressure (760 mm) or 1 atmosphere or 101325 Pascal. Water has a normal boiling point at 212 degrees F. Propane is at -44 degrees F. Above those temperatures propane and water will have a higher vapor pressure and will boil faster or convert more rapidly to a vapor.
Water, for example has a vapor pressure of only 17.5 mm at 70 degrees Fahrenheit, but 760 mm at 212 degrees Fahrenheit. So water likes to stay a liquid unless the atmosphere or surface gets hot. Water vapor is very light. It is about 70 times lighter than air. Once it forms a gas, it rises rapidly to high altitudes where, it is cold enough to become liquid or solid. It then becomes much denser than air, about 833 times heavier than air, so water falls as rain, snow or hail.
Propane likes to stay a gas because it has a vapor pressure of 6000 mm at 70 degrees F. At this temperature propane wants to be a gas 343 times more than water does. We say propane is more volatile than water. To get propane to be a liquid, the temperature must be reduced tremendously down to -44 degrees F before it will begin to change from gas to liquid. Once propane is released from natural gas and oil reservoirs deep within the earth or from our household pressurized storage tanks, it is twice as heavy as air, so tends not to rise, but stays near the ground, creating atmospheric pools of flammable gas that can accumulate in hollows and create explosive zones.
Propane is only slightly soluble in water at 0.04 g/liter so it will not rise on its own to form clouds on our earth. It will tend to remain a gas unless lifted by a hurricane force winds to high altitudes where it could form a temporary liquid which would change back to a gas as it fell.
The volatile gases from the oil that probably will not make it into the rain are those that are much heavier than air. Those that have a low volatility will also not make it easily into the upper atmosphere. Some gases from the oil, like methane and helium will go up to the top of our troposphere (the zone of air we play in, fly airplanes in and in which our clouds and hurricanes develop, in other words the weather zone)
Gases that will cause problems for us through their toxicity and carcinogenetic nature will be from the middle-heavy and heavy compounds. The ether-alcohol compounds, like the Corexit dispersants are generally heavier than the other elements, here and have a poor vapor pressure so they will tend to stay in the water and not vaporize.
A 760 mm vapor pressure or the pressure of our air at sea level is reached by different compounds at different temperatures. Those with a low boiling point reach it first and change from a liquid to a gas at temperatures often below -100 degrees F. These compounds start to vaporize soon after melting from a solid. They are completely gas at their boiling points; often well below the freezing point of water. Air melts from a solid at -352.12 F and is then a liquid which is also slowly turning into a gas, until at -318.10 F; it reaches its boiling point, a vapor pressure of 760mm. All air then exists as a gas as it warms further. Dry air is made of about 78 % nitrogen, 21 % oxygen and about 1% argon. There are trace amounts of water vapor, carbon dioxide, neon, helium, krypton, methane, hydrogen, Xenon and Radon. So air will only begin to condense back to liquid air and rain out of our atmosphere at -318.1 F. There is no place that cold on the earth's surface, so air can only exist here as a gas and only as a liquid when it is compressed and put into compressed air cylinders. The table below ranks the gases into three groups, based on how dense or how heavy they are.
Chemical Compound Approx gas density at kg.m-3 60 F Vapor Pressure [mmHg] at 70 F
What is this stuff called? How light is it? Does it float up? How much does this stuff want to
stay as a gas? The higher the
the number, the more it wants to
remain a gas. The lower the number the
more it wants to return to a liquid or
solid.
LIGHT COMPOUNDS WILL GO UP INTO THE CLOUDS LIKE BALOONS
These compounds in light blue are lighter or equal to nitrogen and oxygen, our predominant gases (air).
Hydrogen is the lightest. Air is the heaviest.
Chemical Compound Approx gas density at kg.m-3 60 F Vapor Pressure [mmHg] at70 F
1) Hydrogen 0.07 kg.m-3 >9865mm
2) Helium 0.14 kg.m-3 >1729mm
3) Water Vapor 0.017 kg.m-3 17.5mm
4) Methane 0.68 kg.m-3 >53200 mm
5) Ammonia * 0.73 kg.m-3 6749 mm
6) Natural gas 0.8 kg.m-3 > 50736mm
7) Carbon Monoxide 1.184 kg.m-3 > 26600 mm
8) Nitrogen* 1.185 kg.m-3 >25839 mm
9) Air 1.2 kg.m-3 >28660 mm
MEDIUM HEAVY COMPOUNDS WILL RISE WITH STRONG UPDRAFTS
Some of these compounds are found in trace amounts in our air such as Argon, ozone and carbon dioxide. Oxygen makes up the heavier fraction of our air.
Chemical Compound Approx gas density at kg.m-3 60 F Vapor Pressure [mmHg] at 70 F
10) Ethane 1.264 kg.m-3 29108mm
11) Oxygen * 1.354 kg.m-3 > 38327mm
12) Hydrogen Sulfide 1.45 kg.m-3 13376 mm
13) Argon 1.67 kg.m-3 >37225mm
14) Methyl Chloride 1.74 kg.m-3 3800mm
Soluble in water (5.325g/l) flammable, carcinogenic and causes birth defects
15) Carbon Dioxide 1.87 kg.m-3 44460mm
16) Ethanol* 1.90 kg.m-3 67.5 mm
17) Ozone * 2.14 kg.m-3 > 760 mm
HEAVY COMPOUNDS WILL TEND TO STAY CLOSE TO THE GROUND OR THE WATER SURFACE.
Chemical Compound Approx gas density at kg.m-3 60 F Vapor Pressure [mmHg] at 70 F
18) Propane 2.42 kg.m-3 6000 mm
19) Butane 2.7 kg.m-3 1650 mm
20) Benzene 2.7 kg.m-3 75 mm
Relative density of the vapor/air-mixture at 20C for benzene (air = 1): 1.2kg.m-3
21) Sulfur Dioxide 2.77 kg.m-3 2614mm
22) Cyclohexane 2.9 kg.m-3 78 mm
23) Pentane 2.99 kg.m-3 460 mm
24) Hexane 3.0 kg.m-3 124 mm
Relative density of the vapor/air-mixture at 20C for hexane (air = 1): 1.3 kg.m-3
25) 1,2 Propane diol (Corexit) 3.12 kg.m-3 0.129 mm
(Soluble/miscible in water)
26) Toluene 3.14 kg.m-3 21 mm
27) Nitrogen dioxide* 3.4 kg.m-3 750 mm
28) Heptane 3.5 kg.m-3 40 mm
29) Ethyl Benzene 3.7 kg.m-3 7.1 mm
30) O-Xylene 3.8 kg.m-3 7mm
31) M-Xylene 3.8 kg.m-3 9 mm
32) P-Xylene 3.8 kg.m-3 9 mm
33) 1,2,4 Trimethyl benzene 4.15 kg.m-3 0.41 mm
34) 3-Ethyl Toluene 4.15 kg.m-3 10.34 mm
35) 1,3,5 Trimethyl benzene 4.15 kg.m-3 1.86 mm
36) Cycloheptane 3.39 kg.m-3 44 mm
37) Methyl cyclohexane 3.4 kg.m-3 37 mm
38) 2-Methyl hexane 3.46 kg.m-3 65 mm
39) 2,2,3 Trimethylbutane 4.14 kg.m-3 48 mm
40) Naphthalene (slightly 5.3 kg.m-3 0.08 mm
Soluble 30mg/liter)
41) 2-Butoxyethanol (Corexit) 4.88 kg.m-3 0.88 mm (Soluble/miscible in water)
42) Polypropylene glycol butyl 5.47 kg.m-3 0.85 mm
ether (PnB) (Corexit) OR
2-butoxy-1-propanol
(Soluble in water 60g per liter)
43) dipropylene glycol (Corexit)7.78 kg.m-3 0.06 mm
mono butyl ether OR
DPnB; 1-(2-butoxy-1
-methylethoxy)-2-
Propanol (Soluble at 45g/liter)
Chemicals or compounds marked with a star "*' are to give the reader an idea of the density of common compounds such as nitrogen in the air and ethanol and ozone, which are NOT found in crude oil. Ethanol can be added to our gasoline.
The dispersant ether-alcohol compounds of Corexit (HIGHLIGHTED IN YELLOW) which are lethal in concentrations of about 2 to 2.5 grams per kilogram body weight in rats on which these products were tested.
I feel WE MUST LOOK OUT for the following volatile, light and deadly and carcinogenic compounds. They are:
1) Benzene
2) Hydrogen Sulfide
3) Methyl chloride
4) Sulfur dioxide
5) Cyclohexane
Methyl chloride is busy forming in large quantities in the Gulf due to the action of salt water on methane gas. Methyl chloride or chloromethane is a highly volatile explosive chemical that has been known to cause birth defects and cancer in the lung, kidney and stomach of animals. It also causes kidney, liver and lung damage. It is being produced in vast quantities in the Gulf by the action of salt water on methane gas. It is also soluble in water. It was once used as a refrigerant and also binds with ozone. It is a light as argon and carbon dioxide but far more deadly. It will therefore be found in the water and air and is a highly reactive, light and mobile compound. It has a faint sweet smell. It is absorbed through the lungs, the skin and the eyes. Frostbite to skin and eyes may result. The Permissible Exposure Limit (PEL) should not exceed 100ppm. A maximum of 5 minutes exposure should not be exceeded in every 3 hours. There is immediate danger to life and health (IDLH) at 2000ppm. See the National Institute for Occupational Safety and health. The link is below.
http://www.cdc.gov/niosh/npg/npgd0403.html
On inhaling chloromethane gas central nervous system effects, like drug overdose results. People begin to feel sleepy, can become dizzy or confused and have difficulty breathing. Gasping and choking, walking and speaking are made difficult. At higher concentrations, paralysis, seizures and coma may happen.
Lastly almost all the compounds from crude oil and natural gas are highly flammable and explosive, IN HIGH CONCENTRATIONS. They may cause a person to stop breathing, by excluding oxygen and staying close to the ground. Avoid low lying areas. These middle heavy and heavy compounds are therefore toxic, asphyxiating and explosive. Check with the daily EPA data base to see how these chemicals might be building up in your area. They will be listed under volatile organic compounds (VOC'S), benzene, xylene and toluene and hydrogen sulfide. Hydrogen sulfide becomes lethal above 350 parts per million. (ppm)
Benzene is the most dangerous of these. It is carcinogenic and more volatile. It is carcinogenic at 1ppm for long term daily exposure or 1000 parts per billion (ppb). Levels are starting to reach 72 parts per billion according to the EPA for the last week of June 2010. CONCENTRATIONS ARE NOW AT ONE 15TH OF THAT LEVEL.
Higher benzene concentrations have been found at these places.
http://www.epa.gov/bpspill/data/taga-june25.pdf
Detection Limit for benzene on 06/25/2010 =1.1ppbv
DATE 6/25/2010 TIME14:23 BENZENE (ppb) 72.831 LATITUDE NORTH 30.319024 LONGITUDE
WEST -87.424129
Chris Landau (geologist/meteorologist)
07/05/2010
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