How To Defend Yourself From Benzene Emissions From Using Gasoline

Defend Yourself From Benzene Emissions When Using GasolineBob Falco, PhDProfessor of Mechanical EngineeringDirector, Institute for Energy Resourcefulness

Cancer rates in the USNewsweek Oct 2012

CFDC Issue Brief: Improving Air Quality through Transportation Fuels 2011

Douglas A. Durante, Executive DirectorClean Fuels Development Coalition4641 Montgomery Avenue | Suite 350 | Bethesda, MD 20814301 718 0077 | 301 718 0606 FAXcfdcinc@aol.com | www.cleanfuelsdc.org

3The average cancer risk in 1999 for Americans was forty-eight in a million, and 29% of this risk was attributable to mobile sourceswhich works out to a mobile-source cancer risk for the average American of about fourteen in a million.1/3 of the cancer risk in the US is due to vehiclesEPA Technology Transfer Network National Air Toxics Assessment, 1996 This results in an ADDITIONAL 4340 deaths every year! OCTANE, CLEAN AIR, AND RENEWABLE FUELS:A MODEST STEP TOWARD ENERGY INDEPENDENCE

C. BOYDEN GRAY & ANDREW R. VARCOE

4Gasoline contains Benzene, and Vehicles create additional Benzene from burning exhaust in their catalytic convertersAdded at the refinery

Created in the catalytic converter

Benzene is the major Carcinogen Benzene produces leukemia

There is no agreed upon lower limit of exposure!No agreed upon minimum exposure that is safe!Health numbers differ by100 million times

Regulatory advisory numbers differ by 1000 times

We dont know how dangerous benzene is!!!

EPA Jan 2012Concentration (mg/m^3 EUlimitBefore showing the experimental results it is recalledthat the threshold value for benzene concentrationstated by EU (Dir. 2000/69) until 31/12/2005 is10 mgm3 as average value of average daily concentrationmeasured in one civil year. The threshold value willdecrease regularly from 1/1/2006 to reach the value of5 mgm3 on 1/1/2010.7

EPA sets cancer odds what are they?The EPA Cancer OddsIncreased cancer deaths13-45 micro grams per cubic meter 1 in 10,000 increase in cancer deaths (30,000/year)1.3-4.5 micro grams per cubic meter 1 in 100,000 increase in cancer deaths (3,000/year).13 to .45 micro grams per cubic meter 1 in 1,000,000 increase in cancer deaths (300/year)The results show that benzene is present at high concentration level in the street canyon. Two-day averageconcentration up to 23.8 mgm3 was detected. In all the samples the benzene concentration at 3m on the road level washigher than the threshold limit value of 10 mgm3.

WHO -- No specific guideline value has been developed for air. Benzene is carcinogenic to humans, and no

safe level of exposure can be recommended. For general guidance, the concentrations of airborne

benzene associated with an excess lifetime risk of leukaemia of 104, 105 and 106 are 17, 1.7 and 0.17 g/m3, respectively.9Ways You Are Exposed to Benzene from Gasolineand the Amounts Inhaled

3 ways to inhale benzene200 pounds per yearThat black smoke is benzeneEvaporative emissions during fill-upGas tank filler cap leaksTail pipe emissionsVapor release during gasoline refueling

We cant see the benzene that this special camera shows as black smoke, but we can smell it.Do you smell the sweet odor of benzene when you fill-up?BENZENE HAS AN ODOR THRESHOLD OF 5 MILLEGRAMS PER CUBIC METERThus, if you are smelling the sweet odor of benzene as you fill-up you are being exposed to 1000 times that determined the 1 in 100,000 number, so that if continually exposed to this you would have a 1 in 100 chance of getting cancer.Of getting leukemia!EPA benzene vapor protectionPhase II installed in 1993 -60% effective

ORVR in all vehicles newer than 2006 98% effective

EPA ORVREPA Phase IIBenzene emissions during fill-up if ORVR is 98% effectiveWhen filling your gas tank the EPA expects emission of 12 ppm over the5 minute fill-up.The industrial standard set by OSHA for the Short Term Exposure Limit is 5 ppm over 15min.The industrial standard set by NIOSH for the Short Term Exposure Limit is 1 ppm over 15 min.Thus,The amount coming out of your tank is 2.5 times the OSHA STELand,12 times the NIOSH STELWe are by no means out of the woods!RecommendationsTo avoid evaporative emission exposure:Do not stand over the gas tank while filling it.Lock the nozzle open, and walk away.Close the windows and doors of your car when filling especially if you have children in it.

Note: the benzene level in the convenience store are likely much higher than outdoors.

Exhaust EmissionsThree-way catalytic converter does reduce benzene emissions in the normal range of driving.However, when accelerating from rest or driving at high speeds the catalytic converter produces more benzene.Furthermore, as shown a few slides ahead, when the catalytic converter is cold, as it is for a few minutes after starting your car, it does not reduce the benzene emissions.The Exhaust Plume

1 in 10,000

Where should you position your car?

Car following in laneWang and Zhang 2012 Coupled turbulence and aerosol dunamics modeling of vehicle exhaust plumes using the CTAG model. Atm Environment Vol 59 Nov 2012 pg 284-293.18The Exhaust PlumeAt 2 car lengths you are exposed to 1/36 the amount of benzene as at the tail pipe.

If you stay right behind the vehicle in front of you,your car is in taking a good portion of the plume, which has benzene concentrations that result in an additional 1-in-10,000 chance of cancer if inhaled regularly.

1 in 10,0001 in 700,00019Catalytic Converter Benzene GenerationBenzene (pre-catalyst) or,during cold start

Benzene (post-catalyst)

At high speed, greater than 75 mph, you should drive even further back. 75 mph20Cold StartingWhen your car is cold started, or you are driving behind one that has just been started, the catalytic converter is not removing the benzene (left plot on previous slide).In this condition the curve on the left (previous slide) shows that the amount of benzene is very, very high at all speeds.Often, when in city driving, you are on the road along with your neighbors going through lots of lights on the way to work while your car is warming up. Conditions are very bad.RecommendationsThe spreading of the exhaust plume is asymmetric and you get its full effect as you follow behind in-lane.1. When in moving traffic, try to stay at least 2 car lengths behind the car in front of you. Your dose will be 1/36 of the emission level at the exhaust pipe.2. When stopping for a light, stop at least 1 car length behind the vehicle in front of you. Although the acceleration blast (see last slide) is up to 20-30x steady state, it will diffuse to - that which exists at the exhaust pipe at 1 car length distance. This is still a high dose. And is especially high if youre in traffic full of newly started cars.3. Change lanes if possible to one with no car stopped in front of you.4. Turn off the A/C and vents at the lights.Gas Tank Cap LeaksIt is estimated that 200 lbs of gasoline leaks from the average cars tank through the gas cap per year. This is 25 gallons.The biggest problem is that this gas will collect in your garage. So you get a good dose as you enter your garage.But, perhaps worse, if you have an attached garage, it will get into your house.RecommendationsCheck the tightness of the gas cap. Replace it if leaks are found. Benzene is very volatile and leaks easily.Let your garage air out before entering it.Make sure the garage door leading into your house is well sealed.Vent your garage.Benzene effects are cumulativeEPA has just enforced the 0.62% benzene limit.Reduction from 1.05%Vapor emission during filling will be halved, but still over the OSHA and NIOSH STEL limits by 125% and 600%This does little to change the exhaust emission picture, for as the Swiss studies show: when cold starting, when accelerating, and when driving at high speed, the benzene emissions can be up to 100x the steady state rates.

And, the EPA allows refineries to trade benzene credits. A result is that some regions are suffering see next slide.Oregon example

ConclusionsThe effects of the exposure to benzene are long term. Think of them as you do the effects of smoking.The western world, and particularly the US has very high rates of leukemia compared to the rest of the world.I leave it to you to decide whether to ignore the precautions.

I also want to make you aware that your car does not need to run on gasoline, and can actually run better on alcohols like ethanol and methanol (see presentations in references on the following slide).ReferencesFalco -- YouTube Channel on Alternative Fuelshttp://www.youtube.com/user/bobfalco12345/videos?flow=grid&view=1Falco SlideShare Sitehttp://www.slideshare.net/BobFalco