Wayne L Feyereisn MD FACP Disclaimer No financial disclosures Research performed on personal time References are based on peer reviewed journal articles except where noted What is needed section is authors conclusions based on the information presented ID: 142381
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Slide1
Potential Public Health Risks of Silica Sand Mining and Processing
Wayne L Feyereisn MD FACPSlide2
DisclaimerNo financial disclosures
Research performed on personal time
References are based on peer reviewed journal articles except where noted
“What is needed “ section is authors conclusions based on the information presented. Slide3
The Main MessageSlide4
What is Silica Sand?Slide5
Why is “our” sand important?
It’s Round – therefore it works better to pipe it down wells and Prop open fractured layers of shale
Its Hard- 8000 PSI of compression strength
Its PlentifulSlide6
Why our sand is plentifulSlide7
Why is it risky?
Our lungs have a great clearing mechanism in the bronchi- Anything larger than 10 microns is effectively cleared. Deposited in the mucus layer, goes to our gut and gets cleared.
Anything smaller than 10 microns, especially those particles smaller than 4 microns easily go all the way to the alveoli (air sacs )Slide8
Size MattersSlide9
Why is it risky?Slide10
What does it look like?Slide11
What else?
Silicosis is a Class 1 Carcinogen- that is it is known to cause cancer.
Implicated in cases of COPD Chronic Obstructive Pulmonary Disease
Implicated in autoimmune diseases including
Scleroderma
Rheumatoid Arthritis
Lupus
Wegener’s Granulomatosis
Scleroderma
Rheumatoid Arthritis
Lupus
Wegener’s Granulomatosis
IgA NephropathySlide12
What is special about Silica?Slide13
What is special about Silica?Slide14
What is special about Silica?
We have special cells (macrophages) to clear anything that makes it to the level of the alveoli (the air sacs).
The macrophages have a limit about how much they can clear
If the limit is exceeded, the cell dies, scar tissue happens. Scar tissue limits lung expansion and oxygen exchange= SILICOSISSlide15
What is “the Limit”?
This is the million dollar question.
Studies based on gold and hardrock mining.
Kreiss &Zehn 41.6 years
Exposure of .05 mg/m3 30 cases/100 workers
Exposure of 0.10 mg/m3 90 cases/100 workers.
Other studies Hnizdo & Suis-Cremer 1993, Muir et al 1991, somewhat similar findingsSlide16
What is the limit?
Only 5 states have standards
The State of California has done several research studies around sand and gravel mines and its OEHHS has set a standard of 3 ug/m3 as a maximal exposure risk (Myers 2010)
It requires monitoring of air around all sand mines and processing plantsSlide17
What is the big deal about standards?
Death rates by state 1996 to 2005 – MN 40 deaths in that period of time. Slide18
Niosh has a different standard of 50ug/m3
How much respirable crystalline silica is the NIOSH REL (Reasonable exposure limits)?
500 micrograms (
μ
g’s)
Photo: Geoff Plumlee, USGS
NIOSH REL = 0.05 mg/m
3
TWA
0.05 mg/m
3
= 50 micrograms (μg)
mg/m
3
1 m
3
of air = 1,000 liters
Normal breathing rate (moderate work, 1 work day) = 10 m
3
(10,000 liters of air)
50 micrograms x 10 m
3
= 500 μg’s Slide19
Really-How much is this?
500 ugSlide20
Why is it difficult to figure out what the silica will do if you have daily exposure?
Data from new cases 1993 to 2006 in Michigan and New Jersey –CDC eWorldSlide21
Its just the construction workers right?
Primary Cases of silicosis 2000-2002 in California by Occupation.Slide22
Facts and Fallacies
Statements made by proponents of sand mining
Facts about the issues they comment onSlide23
Proponent statement“Industrial Silica Sand is Safe”
Depending on use for natural gas or for oil. Sand used for fracking is generally in the 20-70 sieve size range.
Pure round sand, with no contaminants, after processing- “Should be safe”
BUTSlide24
We just take off the top layers which are the Industrial Sand that carries no health risk-we leave the rest aloneSlide25
Silica Sand is a mix
25-50% of sand they mine they refer to as “fines”
Simply put this is sand below their usable size limit of .2mm or 70 sieve
All sands are mixtures in their natural state though there may be more fine sand at the bottom of a vein of sand than near the top. Slide26
What about the washed sand when its ready for transport its safe correct?
Worker Exposure to Crystalline Silica During Hydraulic Fracturing – Eric Esswein MSPH et al.Slide27
Silica exceeded exposure limits
92 of 116 (79%) air samples collected at hydraulic fracturing sites exceeded the NIOSH REL for PM2.5
36 of the 116 (31%) samples exceeded the NIOSH REL by a factor of 10 or more.
The significance of these findings is that even if workers are properly using half-mask air-purifying respirators, they would not be sufficiently protected . Slide28
Silica sand is no different than Sandbox SandSlide29
FallacyHow Industrial Silica Sand is different
MAGNITUDE:1 cubic yard vs 1000’s of cubic yards at a sand mine
DURATION:Sandbox’s operate for an hour Sand Mines operate for 16 hours day
AGGITATION AND MANIPULATION: Front end loaders, crushers, blasting, trucking vs hand shovel and plastic bucket.Slide30
Silica Particulate Monitoring
This is a Sharp Thermoscientific Model 5030 It can detect PM2.5 down to
0.5 ug/ m3Slide31
EOG Chippewa FallsMonitoring by Crispin Pierce PhD and students
Ongoing studies with perimeter monitoring.
Studying PM 10 PM2.5 Preliminary finding of some readings above New York standards and at or near current California standards. Slide32
Ambient Silica is At or Near Standards from Other States
WOHL
Preliminary PM 4 silica data from an industry-sponsored study (John Richards, PhD) has measured the presence of silica at EOG (and the Towns of Howard and Cooks Valley mines) at around 0.0005—0.001 mg/m3).Slide33
Silica StandardsStandards in 5 states for Silica in Ambient Air
California 3 mcg/m3- based on non-cancer (silicosis risk)
Texas 0.27 mcg/m3- based on cancer risk exceeding 1/100,000
New York 0.6 mcg/m3
Minnesota NO STANDARD
Wisconsin NO STANDARD
Are you seeing a problem here?Slide34
PM2.5 Study EOG Plant Operating
By Crispin Pierce et al U of W Eau Claire
http://people.uwec.edu/piercech/InitialPM.pdfSlide35
PM 2.5 Under Varying conditions
Crispin Pierce et al http://people.uwec.edu/piercech/InitialPM.pdf Slide36
We use polyacrylamide as a flocculent and it is perfectly safe
Fact or Fallacy?
Polyacrylamide IS safe.
It breaks down to Acrylamide- not safe at all
Heat breaks it down
Shear forces break it down
Acrylamide is a neurotoxin, that is, it damages peripheral nerves and the brain. It also is considered a class 2b carcinogenSlide37
Acrylamide
Its concentration can increase in a holding pond due to UV irradiation. It also after a period of time will start to decrease in concentration.
It can be spread in a thin layer over dirt and be rendered inert.
If it washes quickly through sand into the aquifer it is toxic
.5 parts per billion makes water undrinkable
World Health Organization standard 2011Slide38
Spills don’t happen do they?
Preferred Sands Blair WisconsinSlide39
Sand Spills don’t happen do they?When the pond spills so does the acrylamide
Soderbeck mine near Grantsburg WISlide40
b
Sediment-filled water overflows holding pond and flows downhill to creek
Polluted water flows to beaver dam, then to St. Croix RiverSlide41
Additional Medical Risks
Diesel Particulates
Known carcinogen in concentration
It shortens the lives of 22,000 people/year
http://www.4cleanair.org/comments/cancerriskreport.pdf
Known risk for cardiovascular events -50% increased risk of heart attacks with acute exposure. Greater risk walking or riding a bike than in a car.Slide42
Additional Medical Risks
Diesel Particulates
http://www.catf.us/diesel/dieselhealth/county.php?c=27169&site=0
Winona
The
lifetime
cancer risk from
diesel soot
in your community exceeds the risk of all other air toxins tracked by EPA combined. 80
th
Percentile of all US Counties
The average lifetime diesel soot cancer risk for a resident of Winona County is 1 in 22,418
This risk is 45 times greater than EPA's acceptable cancer level of 1 in a million.Slide43
How the Risk from Diesel Soot in Winona County Compares to Other Minnesota Counties:Rank Within State: 13 of 87 counties
Winona counties cancer risk is 45 times greater than EPA's acceptable cancer level of 1 in a millionSlide44
Diesel use by minesEAW’s for Dobelstein and Yoder (example) each would use 500,000 gallons of diesel /year
All of Minnesota’s diesel use per day of #2 diesel at the retail level is 250,000 gallonsSlide45
Additional Medical RisksTraffic Safety
1 in 5 collisions with trucks this size= death
Water Quality
During Mining
Diesel and hydraulic leakage
Chemicals in sand hauled back to mineSlide46
Additional Medical RisksWater Quality Risks after mining complete
Alteration in pH due to sulfites exposed during mining
Contaminants entering ground water through Karst Topography- continued enhanced risk of chemicals and bacteria after finished with reduced filtration bed.Slide47
What is needed
Silica air standards , review of current standards and determine which one, but choose one
Require that all sand mining and processing operations install air monitors every 1000 feet on the perimeter and meet three standards:
The 3 or .27 or 0.6 ug/m3 standard for silica
The EPA PM 10 NAAQS standard
The EPA PM 2.5 standardsSlide48
What is neededAcrylamide monitoring of pond water
Acrylamide monitoring of drying facilities at sand processing site for air
Acrylamide monitoring of sand returned to the sand mine
Minimize diesel use (no roadway transport of sand)Slide49
What is needed.
Sand mines and processing are coming AHEAD of the regulation-That is a problem
The safest way to mine and process sand is:
Start by having the plant and processing facility in the least densely populated area’s
-The further from the epicenter of this activity the lower the risk
Rail spurs directly into the facility-No trucks to transportSlide50
The Main MessageSlide51
Questions?
Wayne L Feyereisn M.D. FACPSlide52
References
Silica Sand Mining Information. Winona County.
http://www.co.winona.mn.us/page/3038
Occupational silica exposure and risk of various diseases: an analysis using death certificates from 27 states of the United States.
Calvert, G M 1; Rice, F L 2; Boiano, J M 1; Sheehy, J W 3; Sanderson, W T 1 Occupational & Environmental Medicine. 60(2):122-129, February 2003.
Silica, crystalline (as respirable dust). Nov 2010. Centers for Disease Control and Prevention.
http://www.cdc.gov/niosh/npg/npgd0684.html
Exposure to silica and silicosis among tin miners in China: exposure–response analyses and risk assessment. Occup. Environ. Med. 58, 31–37. 2001. Chen, W., Zhuang, Z., AttWeld, M.D., Chen, B.T., Gao, P., Harrison, J.C., Fu, C., Chen, J.Q., Wallace, W.E.,
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References
Silicosis: State-Based Surveillance. Dec 2012. Nation Institute for Occupational Safety and Health. Centers for Disease Control and Prevention.
http://www2a.cdc.gov/drds/worldreportdata/FigureTableDetails.asp?FigureTableID=2599&GroupRefNumber=F03-05
Worker Exposure to Crystalline Silica During Hydraulic Fracturing. May 2012. Esswein E, MSPH, Kiefer M, MS, Snawder J. PhD, Breitenstein M, BS.
http://blogs.cdc.gov/niosh-science-blog/2012/05/silica-fracking/
Regulatory Toxicology and Pharmacology 43 (2005) 292–300. doi:10.1016/j.yrtph.2005.08.003. Development of a chronic inhalation reference level for respirable crystalline silica. Collins J, Salmon A, Brown J, Marty M, Alexee G.
Silica Crystalline Forms. Oct 2009. Development Support Document. TCEQ.
http://www.tceq.com/assets/public/implementation/tox/dsd/final/october09/silica_crystalline_forms.pdf
Fracturing Sand Mining and Processing[Absract]. Epidemiology. 23(5s) (ISEE 2012 Conference Abstracts). September 2012. University of Wisconsin-Eau Claire. Pierce C, Fay K, Nelson G.Slide54
References
Crispin Pierce. Personal Communication and Posted Results. UW Eau Claire. http://www.uwec.edu/CONHS/programs/enph/silica/silicaresearch1.htm
Environmental Degradation of Polyacrylamides II. Effects of Environmental (Outdoor) Exposure Ecotoxicology and Environmental Safety v.37, n.1, 1jun97
Also see
Monsanto, Roundup, and Glyphosate
. Eldon A. Smith,*,1 Susan L. Prues,* and Frederick W. Oehme
*GEO-CENTERS, Inc., at Naval Medical Research Institute Detachment (Toxicology), Building 433, Area B, 2612 Fifth Street, Wright-Patterson AFB, Ohio
45433-7903; and †Comparative Toxicology Laboratories, College of Veterinary Medicine
"Environmental degradation of polyacrylamides. II. Effects of environmental (outdoor) exposure."
Ecotoxicology and Environmental Safety
37 (1): 76–91. (June 1997).
DOI
:
10.1006/eesa.1997.1527
. Smith EA, Prues SL, Oehme FW
http://www.mindfully.org/Plastic/Polymers/Polyacrylamides-Degradation1jun97.htm
.
Degradation of Polyacrylamide by Shear Forces. Taeho Rho, Jonseong Park et al “degradation of polyacrylamide in dilute solution” Polymer Degradation and Stability 51 (1996) 287-293 rnnfm.korea.ac.kr/publication/2008/1995_51_287.pdfSlide55
References
Basic Information about Acrylamide in Drinking Water. May 2012. United States Environmental Protection Agency.
http://water.epa.gov/drink/contaminants/basicinformation/acrylamide.cfm
Acrylamide in Drinking-water. WHO/SDE/WSH/03.04/71/Rev/1
http://www.who.int/water_sanitation_health/dwq/chemicals/acrylamide.pdf
.
National Toxicology Program, Department of Health and Human Services. Diesel exhaust particulates report on carcinogens. 12th Edition. 2011. http://ntp.niehs.nih.gov/ntp/roc/twelfth/profiles/DieselExhaustParticulates.pdf.
International Agency for Research on Cancer. Monographs on the Evaluation of Carcinogenic Risks to Humans. Diesel and gasoline engine exhausts and some nitroarenes. Lyon (France): vol. 105; 2012. p. 5–12. Available at: http://www.iarc.fr/en/mediacentre/
aircrews/2012/mono105-info.php.
Slide56
References
McDonald JD, Campen MJ, Harrod KS, et al. Engine-operating load influences diesel exhaust
Composition and cardiopulmonary and immune responses. Environ Health Perspective 2011; 119(8):1136–41. Pronk A, Coble J, Stewart PA. Occupational exposure to diesel exhaust: a literature review. J Expo Sci Environ Epidemiology 2009; 19:443–57.
Acute exposure to diesel exhausts induces immediate platelet activation. Wauters A., Dreyfuss C., Hendrick P., Wijns W., Pradier O., Berkenboom G., Van De Borne P., Argacha J.-F. European Heart Journal. ESC Congress 2012 Munchen Germany... Conference Publication: (var.pagings). 33 (pp 307-308), August 2012. [Journal: Conference Abstract] Oxford University Press
Diesel Soot Health Impacts. Clean air Task Force.
http://www.catf.us/diesel/dieselhealth/faq.php?site=0
A Multi-City Investigation of Exposure to Diesel Exhaust in Multiple Commuting Modes. CATF Special Report 2007-1. Version 1.1 April 2010. L. Bruce Hill, Ph.D. James Gooch.
http://www.catf.us/resources/publications/files/Multi_City_Commuter_Exposure_Report.pdf