Tuesday, June 30, 2015

Silica Sand on OSHA's Cross Hairs: Over two million American workers are exposed to silica dust in industries like hydrualic fracturing, construction, mining, road repair and sand blasting.

Proposed OSHA regulations target fatal disease that remains daily risk for many workers

June 29, 2015
Originally published on June 30, 2015 9:52 am 
 
Over two million American workers are exposed to silica dust in industries like construction, mining, road repair and sand blasting. WXXI’s Michelle Faust reports the Occupational Safety and Health Administration - OSHA - is now pushing for tougher limits on how much silica dust they can be exposed to in the workplace. But the proposed rules will come too late for many workers who’ve already contracted the potentially fatal lung disease, silicosis. 
“It was one particular job that was up in Rome, New York. We had these big brick buildings and we had to remove a lot of the damaged brick…And that’s how I got sick.”

Chris Johnson from Port Byron, New York learned about silicosis the hard way. He’s a mason and worked in construction since he graduated from high school, like his father, uncles, and cousins. He was 29-years old on the job that changed his life.

Credit www.newlabor.org 
 
The white disposable masks Johnson wore on the job were supposed to protect him.
 
“After every time I got done cutting you’d have stuff up in your nostrils that you’d blow out.”

The tiny dust particles that ended up in Johnson’s lungs were silica - one of the most common earth minerals. Job’s like his that call for drilling or cutting into bricks or mortar send tiny silica particles into the air.  In Johnson’s case, the exposure was so acute silicosis came on in just a few months. For most people who contract the disease--it’s plagued stone workers since the Ancient Greeks - it develops over five to ten years. 

The Rome Housing Authority buildings where Chris Johnson worked.
Credit Maryam Jameel/Center for Public Integrity
 
Dr. Bill Beckett was Johnson’s physician. He says workers can’t see or feel the silica they’re inhaling.
 
“And it doesn’t really bother you, but the dust is building up in your lungs. So, after a period of what may be months or years, there is enough silica dust stuck in your lungs that it can cause permanent damage. And by then, it’s too late to do anything about it.”
 
The U.S. Department of Labor produced the film Stop Silicosis way back in 1938 and in its narration, “A wave of fear was sweeping the country. Silicosis was taking its toll from the ranks of American Workers The cause of the disease: dust. The results of the disease: disablement, poverty, death. The cure for the disease: none.”
Nearly 80 years on since that  film was made, there are still 1600 new cases of silicosis every year and around 100 fatalities

It’s time says David Michaels, Assistant Secretary at OSHA, to put tougher regulations in place. 

Silica is probably the major chemical exposure out there that we know of that’s causing hundreds of workers to get sick every year that we have a totally antiquated standard for. When we issued that standard, and once it goes into effect, it’s going to prevent hundreds of cases of silicosis every year, and save hundreds of lives, both from silicosis but also lung cancer.”
 
The benchmark proposed by OSHA back in 2011 would halve the current Permissible Exposure Levels for respirable silica over 8-hours. The agency estimates that well over 600,000 construction workers  exceed those levels on any given day.

Keeping the silica out of workers lungs is a matter of keeping the dust down with water or vacuum. In some cases workers would need to wear a respirator.
Michaels sees the new OSHA rules as a simple solution that will save lives, but the Construction Industry Safety Coalition sees a threat to jobs. 

In a letter to Michaels the industry calls it the most expensive OSHA rule ever, with an estimated 4.9 billion dollar price tag threatening more than 50,000 jobs.
But Michaels and OSHA disagree with industry numbers. They say they’re committed to working with the Obama administration to get them adopted despite a lengthy bottle neck in the Office of Management and Budget as the rules are reviewed.

President Obama has made it very clear – he is committed to getting the silica standard out while he’s president.  And we will work with him and the White House to make sure that happens.”

Michael’s acknowledges that OSHA’s rate of inspections - around 40,000 a year - has been static over the past decades and that the new standards will rely largely on employers to implement them.

Now aged 40, married and with three stepchildren, Chris Johnson's life expectancy is an open question. Although financially secure for the moment, He’ll never work again.

Chris Johnson from Port Byron, New York
Credit Maryam Jameel/Center for Public Integrity
 
 
Looking back, he wishes he could have avoided the whole process.
“So if you can protect yourself and wear a respirator rather than it affecting your whole entire life, and possible death, I think it’s five seconds taking the respirator and putting it on, it’s more important.”

This story was reported and produced through a partnership with the Center for Public Integrity. For more on this story visit publicintegrity.org

 ///-------------------////



Cancer-Causing Substances in the Workplace and Home -Crystalline Silica

What is crystalline silica?
Crystalline silica is a basic component of soil, sand, granite, and many other minerals.  It is used extensively in many industrial applications because of its unique physical and chemical properties.  Quartz is the most common form of crystalline silica.  Cristobalite and tridymite are two other forms of crystalline silica.  All three forms may become respirable size particles when workers chip, cut, drill, or grind objects that contain crystalline silica.  During the last few years, thousands of workers have been exposed to crystalline silica during hydraulic fracturing activities because several thousand tons of pure crystalline silica are injected into the subsurface at every single gas well to keep the shale fractures open.
Sand, the most common size fraction of natural crystalline silica, has many applications. For example, it may be used in foundry castings, Portland cement, abrasives and sandblasting materials, and hydraulic fracturing.  It may also be used as a raw material for the production of silicon and ferrosilicon metals, or as a filter for large volumes of water, i.e. in municipal water and sewage treatment plants.  When sand has more than 98% silica and low iron content it can be used for glass and ceramic production.  Flours are formed by the grinding or quartz, quartzite, sand and sandstone. Flours are very fine grades of crystalline silica and are used in the ceramic and pottery industry, in the manufacturing of chrysotile cement, as a filler in rubber and paints and as an abrasive in soaps and cleaners.
What are the hazards of crystalline silica?
Silica exposure remains a serious threat to more than 2 million U.S. workers, including more than 100,000 workers in high risk jobs such as abrasive blasting, hydraulic fracturing, foundry work, stonecutting, rock drilling, quarry work and tunneling.  The seriousness of the health hazards associated with silica exposure is demonstrated by the fatalities and disabling illnesses that continue to occur in sandblasters and rockdrillers.  Crystalline silica has been classified as a human lung carcinogen. Additionally, breathing crystalline silica dust can cause silicosis, which in severe cases can be disabling, or even fatal.  The respirable silica dust enters the lungs and causes the formation of scar tissue, thus reducing the lungs’ ability to take in oxygen.  There is no cure for silicosis.  Since silicosis affects lung function, it makes one more susceptible to lung infections like tuberculosis.  In addition, smoking causes lung damage and adds to the damage caused by breathing silica dust.
What are the symptoms of silicosis?
Silicosis is classified into three types:  chronic /classic, accelerated, and acute.
Chronic/classic silicosis, the most common, occurs after 15–20 years of moderate to low exposures to respirable crystalline silica.  Symptoms associated with chronic silicosis may or may not be obvious; therefore, workers need to have a chest x-ray to determine if there is lung damage.  As the disease progresses, the worker may experience shortness of breath upon exercising and have clinical signs of poor oxygen/carbon dioxide exchange.  In the later stages, the worker may experience fatigue, extreme shortness of breath, chest pain, or respiratory failure.
Accelerated silicosis can occur after 5–10 years of high exposures to respirable crystalline silica.  Symptoms include severe shortness of breath, weakness, and weight loss.  The onset of symptoms takes longer than in acute silicosis.
Acute silicosis occurs after a few months or as long as 2 years following exposures to extremely high concentrations of respirable crystalline silica.  Symptoms of acute silicosis include severe disabling shortness of breath, weakness, and weight loss, which often leads to death.
Where are construction workers exposed to crystalline silica?
Exposure occurs during many different construction activities.  The most severe exposures generally occur during abrasive blasting with sand to remove paint and rust from bridges, tanks, concrete structures, and other surfaces.  Other construction activities that may result in severe exposure include: jack hammering, rock/well drilling, hydraulic fracturing, frac sand mining and loading and unloading, concrete mixing, concrete drilling, brick and concrete block cutting and sawing, tuck pointing, tunneling operations.
Where are general industry employees exposed to crystalline silica dust?
The most severe exposures to crystalline silica result from abrasive blasting, which is done to clean and smooth irregularities from molds, jewelry, and foundry castings, finish tombstones, etch or frost glass, or remove paint, oils, rust, or dirt form objects needing to be repainted or treated.  Other exposures to silica dust occur in cement and brick manufacturing, asphalt pavement manufacturing, china and ceramic manufacturing and the tool and die, steel and foundry industries.  Crystalline silica is used in manufacturing, household abrasives, adhesives, paints, soaps, and glass.  Additionally, crystalline silica exposures occur in the maintenance, repair and replacement of refractory brick furnace linings.
In the maritime industry, shipyard employees are exposed to silica primarily in abrasive blasting operations to remove paint and clean and prepare steel hulls, bulkheads, decks, and tanks for paints and coatings.
How is OSHA addressing exposure to crystalline silica?
OSHA has an established Permissible Exposure Limit, or PEL, which is the maximum amount of crystalline silica to which workers may be exposed during an 8-hour work shift (29 CFR 1926.55, 1910.1000). OSHA also requires hazard communication training for workers exposed to crystalline silica, and requires a respirator protection program until engineering controls are implemented.  Additionally, OSHA has a National Emphasis Program (NEP) for Crystalline Silica exposure to identify, reduce, and eliminate health hazards associated with occupational exposures.
What can employers/employees do to protect against exposures to crystalline silica?
Replace crystalline silica materials with safer substitutes, whenever possible.
Provide engineering or administrative controls, where feasible, such as local exhaust ventilation, and blasting cabinets.  Where necessary to reduce exposures below the PEL, use protective equipment or other protective measures.
Use all available work practices to control dust exposures, such as water sprays.
Wear only a N95 NIOSH certified respirator, if respirator protection is required.  Do not alter the respirator. Do not wear a tight-fitting respirator with a beard or mustache that prevents a good seal between the respirator and the face.
Wear only a Type CE abrasive-blast supplied-air respirator for abrasive blasting.
Wear disposable or washable work clothes and shower if facilities are available. Vacuum the dust from your clothes or change into clean clothing before leaving the work site.
Participate in training, exposure monitoring, and health screening and surveillance programs to monitor any adverse health effects caused by crystalline silica exposures.
Be aware of the operations and job tasks creating crystalline silica exposures in your workplace environment and know how to protect yourself.
Be aware of the health hazards related to exposures to crystalline silica.  Smoking adds to the lung damage caused by silica exposures.
Do not eat, drink, smoke, or apply cosmetics in areas where crystalline silica dust is present.  Wash your hands and face outside of dusty areas before performing any of these activities.
Remember: If it’s silica, it’s not just dust.
How can I get more information on safety and health?
OSHA has various publications, standards, technical assistance, and compliance tools to help you, and offers extensive assistance through workplace consultation, voluntary protection programs, strategic partnerships, alliances, state plans, grants, training, and education.  OSHA’s Safety and Health Program Management Guidelines (Federal Register 54:3904-3916, January 26, 1989) detail elements critical to the development of a successful safety and health management system. This and other information are available on OSHA’s website.
For one free copy of OSHA publications, send a self-addressed mailing label to OSHA Publications Office, 200 Constitution Avenue N.W., N-3101, Washington, DC 20210; or send a request to our fax at (202) 693–2498, or call us toll-free at (800) 321–OSHA.
To order OSHA publications online at www.osha.gov, go to Publications and follow the instructions for ordering.
To file a complaint by phone, report an emergency, or get OSHA advice, assistance, or products, contact your nearest OSHA office under the U.S. Department of Labor listing in your phone book, or call toll-free at (800) 321OSHA (6742). The teletypewriter (TTY) number is (877) 889–5627.
To file a complaint online or obtain more information on OSHA federal and state programs, visit OSHA’s website.
This is one in a series of informational fact sheets highlighting OSHA programs, policies, or standards. It does not impose any new compliance requirements. For a comprehensive list of compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal Regulations. This information will be made available to sensory-impaired individuals upon request. The voice phone is (202) 693–1999. See also OSHA’s website at www.osha.gov.






Silica (Crystalline)
Fibers and Dusts – Known Carcinogen (IARC 1)
CAS No. 14808-60-7 (Quartz)
CAS No. 14464-46-1 (Cristabolite)

Photo: Wikimedia Commons [1]
IARC Monograph Vol. 68, 1997 (Group 1)
IARC Monograph Vol. 100C, 2011. (Group 1)
Silica is one of the most common minerals on earth and is a basic component of soil, sand, and rocks including granite and quartzite. Silica exists in both crystalline and amorphous (non-crystalline) forms.[2] Conversion from amorphous to crystalline form can occur at high heat.[3] Quartz is the most common form of crystalline silica and the most commonly used industrially.[4] Cristobalite also has important industrial uses. Tridymite is found in rocks and is not an important industrial product.[4] There are numerous other synonyms and product names for silica; see IARC for more information.[2]
Crystalline silica is used extensively in many industrial applications because of its unique physical and chemical properties.[4] Health concerns arise when silica containing products are disturbed by grinding, cutting, drilling or chipping, creating respirable particulate.[5]
IARC’s classification in 1997 of crystalline silica as a Group 1 carcinogen (carcinogenic to humans) is specifically for quartz and cristobalite silica inhaled from occupational sources.[2] A recent IARC review of Class 1 carcinogens reaffirmed this classification.[15] Epidemiological studies have shown a relationship between occupational exposure to crystalline silica and increased risk of lung cancer, with the strongest link in quarry and granite workers and workers involved in ceramic, pottery, refractory brick and diatomaceous earth industries.[4] Increased risk was not evident with exposure to amorphous silica.[2]
Silicosis, a non-reversible fibrotic lung disease, is caused by the inhalation of crystalline silica particles.[6] Silicosis is typically categorized as chronic (> 10 years exposure), accelerated (high concentrations over 5-10 years) or acute (short term exposure at high concentrations).[5] Besides silicosis and lung cancer, occupational silica exposure has also been linked to pulmonary tuberculosis, chronic obstructive pulmonary disease, and autoimmune disease (rheumatoid arthritis).[7,8]
Occupational Exposure Limits (OEL)
Canadian Jurisdictions
OEL1 (mg/m3)
Canada Labour Code
0.025 [r]
AB, BC, MB, NL, NS, PE
0.025 [r]
NB
0.1 [r]
SK
0.05 [r, cristobalite, quartz]
0.1 [r, tripoli]
ON
0.05 [cristobalite]
0.1 [quartz, tripoli]
NU, NT, QC
0.05 [r, cristobalite, tridymite]
0.1 [r, quartz, tripoli]
YT
300 particles/mL [quartz]
150 particles/mL [cristobalite, tridymite, tripoli]
Other Jurisdiction
OEL (mg/m3)
ACGIH 2014 TLV
0.025 [r]
1: OEL for both quartz and cristobalite, unless otherwise specified.
2: Exposure limit determined with a konimeter, an instrument that measures dust in mines.
mg/m3 = milligrams per cubic meter
r = respirable fraction
Canadian Environmental Guidelines
Jurisdiction
Limit
Year
Health Canada
DSL – high priority substances with greatest potential for exposure (quartz cristobalite)
2006[9]
Challenge to Industry
Batch 12B (Health) for quartz and cristobalite
2006[10]
Crystalline silica was not included in other Canadian government environmental guidelines reviewed.[11] For further information on silica and the Hazardous Products Act and Controlled Products Regulations in Canada, please refer to the Health Canada pages for non-respirable silica[12] and diatomaceous earth.[13]
Applications for silica differ depending on the particle size, which is divided into three general size categories: lump silica, 0.3 – 15 cm; sand, 75 μm – 3 mm; and flour, < 75 μm. The approximate proportion of use per size category in Canada in 2005 were lump (29%), sand (68%) and flour (3%).[14]
Lump silica is used as flux for smelting operations, in silicon and ferrosilicon alloys and for silica brick.[14] This size fraction is not of concern for health effects as it is too large to inhale. Sand, the most common size fraction of natural crystalline silica, has many applications. For example, it may be used in foundry castings, Portland cement, abrasives and sandblasting materials, and hydraulic fracturing.[4,14] It may also be used as a raw material for the production of silicon and ferrosilicon metals, or as a filter for large volumes of water, i.e. in municipal water and sewage treatment plants.[4,14] When sand has more than 98% silica and low iron content it can be used for glass and ceramic production.[4] Flours are formed by the grinding or quartz, quartzite, sand and sandstone. Flours are very fine grades of crystalline silica and are used in the ceramic and pottery industry, in the manufacturing of chrysotile cement, as a filler in rubber and paints and as an abrasive in soaps and cleaners.[14]
Quebec, Ontario and Alberta are the primary silica producers in Canada, followed by Saskatchewan, BC and Nova Scotia. There are silica deposits in all Canadian provinces, however not all are in commercial operation.[14]
Canadian production of silica fulfills most of its domestic requirements, however high quality sands for glass and foundry applications are imported from the US.[14]
Production and Trade
Activity
Quantity
Year
Canadian Production*
ON: 435,537 t
B: 515,409 t
QC: 523,313 t
TOTAL: 1,893,022 t
2006[14]
Industrial Consumption of Silica
2,568,393 t
2003-2005[14]
Export: Mainly to US
154,903 t of ‘silica sands and quartz sands’
2010[17]
Import: Mainly from US
1,271,444 t of ‘silica sands and quartz sands’
2010[17]
*These totals represent all quartz production, not exclusively respirable silica; they likely include this fraction, however.
t = tonne
Inhalation is the most important route of occupational exposure to silica.[4] CAREX Canada estimates that approximately 380,000 Canadians are exposed to silica in their workplace. The largest industrial group exposed is construction. More specifically, the largest exposed groups are within the construction sector are specialty trade contractors, building construction, and heavy and civil engineering construction. In terms of occupation, the largest occupational groups exposed to silica were construction trades labourers, heavy equipment operators, and plasterers and drywallers.
Exposure to crystalline silica, especially quartz, may also occur in a number of other industries and occupations due to its wide and variable use.[2] Workers can be exposed in industries such as mining, agriculture, and various manufacturing industries.[2,4,5] Job tasks that are typically associated with exposure include grinding, sandblasting, crushing, chipping, mixing and plowing.
For more information, see CAREX Canada’s occupational exposure estimates for silica.
Our team has performed a detailed scan of exposure control resources and assembled a compilation of key publications and resources. These are organized by type of exposure (environmental or occupational) and by specificity (general or carcinogen-specific). Please visit our Exposures Reduction Resources page to view.
http://www.carexcanada.ca/cdn/P_PolicyDirectoryEN_150.jpg
We also recommend exploring the Prevention Policies Directory, a freely-accessible online tool offering information on policies related to cancer and chronic disease prevention. Providing summaries of the policies and direct access to the policy documents, the Directory allows users to search by carcinogen, risk factor, jurisdiction, geographical location, and document type. To learn more about policies specific to silica on the Directory, click here. For questions about this resource, please contact a member of the Prevention Team at the Canadian Partnership Against Cancer at primary.prevention@partnershipagainstcancer.ca.
  1. Wikimedia Commons Photo: A-quartz
  2. IARC monograph summary, Volume 68 (1997) (PDF)
  3. Key-Schwartz, R., et al (2003) and NOISH 2002; NIOSH Manual of Analytical Methods: Determination of Airborne Crystalline Silica
  4. NTP 12th Report on Carcinogens for Silica, Crystalline (2011) (PDF)
  5. OSHA Fact Sheet: Crystalline Silica Exposure Health Hazard Information (2002) (PDF)
  6. CICAD Document No. 24: Crystalline Silica, Quartz (2000) (PDF)
  7. G M Calvert, F L Rice, J M Boiano, J W Sheehy, W T Sanderson (2003). ‘Occupational silica exposure and risk of various diseases: an analysis using death certificates from 27 states of the United States.’ Occupational & Environmental Medicine; 60:122-129
  8. Parks, C. et al (1999). ‘Occupational Exposure to Crystalline Silica and Autoimmune Disease.’ Environmental Health Perspectives, Vol. 105, Supplement 7, pp. 793-802
  9. Health Canada’s Prioritization of the DSL
  10. Challenge to Industry List of Substances
  11. CEPA List of Toxic Substances
  12. Health Canada Environmental and Workplace Health. Substance Specific Issues: Silica
  13. Health Canada Environmental and Workplace Health. Substance Specific Issues: Diatomaceous earth (calcined) with respect to carcinogenicity
  14. Canadian Minerals Yearbooks: Silica/Quartz, 2006
  15. IARC Monograph Volume 100: A review of human carcinogens—Part C: metals, arsenic, dusts, and fibres (2009)
  16. US EPA: Ambient Levels and Non-cancer Health Effects of Inhaled Crystalline and Amorphous Silica Health Issue Assessment (1996)
  17. TradeMap (Free subscription required)
Other Resources
  1. Maciejewska, A. (2008). ‘Occupational Exposure Assessment for Crystalline Silica Dust: Approach in Poland and Worldwide.’ International Journal of Occupational Medicine and Environmental Health, Vol. 21, No. 1, pp. 1-23 (PD