Because the 100-year-old Central Cocoanut neighborhood lies directly in the path of the facilitys emissions, what appears to be potentially toxic concrete dust blankets the homes, the cars, the leaves on trees, the gutters that line the streets, and the playground equipment at Mary Dean Park three blocks away.
For years heavy equipment on the three-acre parcel has rattled windows, shuttered to keep out the fine gray powder. In emails and phone calls to public officials, residents have expressed fears that the powder that clings to everything contains asbestos and other cancer-causing elements.
But it wasnt until residents took their concerns to the Florida Department of Environmental Protectionthat there was anypromise of change. Even after major issues were identified by local and state environmental officials, U.S. Recycling has been allowed to continue flouting the rules, so far without apparentrepercussions.
City and county officials have inspected the property almost a dozen times since 2016 and have dismissed each citizen complaint, records show. In February, a joint inspection by local and state environmental officials revealed that U.S. Recycling was operating a concrete crusher on the three-acre parcel without a state-mandated air quality permit.
Christopher Williams, the owner of U.S. Recycling, continued to use the crusher, a machine that pulverizes concrete, even after officials told him to stop. After Williams obtained the permit, a localofficial said he illegally refused to allow inspectors inside unless officials revealed who was complaining against him. Records show the county has yet to take enforcement action against him.
In 2009, just a year before the property was sold to U.S. Recycling, an environmental consulting firm had detected high levels of arsenic in the groundwater. The cancer-causing metal was four times higher than state requirements.
Hardened concrete can be crushed and reused as a construction material. It can be used as a road base andas fill at someconstruction sites. Its unclear how long Williams has been allowed to operate on the property without a permit, which would have required him to follow best management practices and monitor and report samples.
Its also unclear whether Williams was following rules outlined by the federal Environmental Protection Agency. In communication with DEP, Williams vowedto install water spray bars to mitigate dust emissions and maintain landscaping to reduce fugitive emissions, according to his Feb. 12 permit application.
Sarasota County maintains its own oversight of air and water quality. Its responsible for responding to and investigating these complaints. The county declined repeatedrequests to be interviewed for this story.
Tracy Dunkin lives on 15th Street and her front door is about as far from the facility as the pitchers mound is from home plate at Ed Smith Stadium. From her window, she and her neighbors have watched children avoid dust clouds as trucks roar down Central Avenue loaded with slabs of old roadway and concrete.
But dust problems dont just stop at 15th Street. Prevailing winds carry it as far away as Mary Dean Park three blocks away. A city worker told the Herald-Tribune that he comes to the park to clean the dust off playground equipment everyfew weeks.
Air pollution due to fine particulate matter can lead to cardiovascular and respiratory disease and cancer, according to the World Health Organization. The ZIPcodes that make up Newtown and the Central Cocoanut district have the highest rate of emergency room admissions and hospitalizations for asthma of any ZIP code in Florida, according to the Florida Department of Health.
Dr. Lisa Merritt is the founder and director of the Multicultural Health Institute, the group formed over concerns that fine particulate matter that results from facilities processing cement on county land in Sarasota County just across the street from Booker High School.
Where you live shouldnt divide whether you have to worry about the toxic effects of environmental pollution, Merritt said. Then there are the psychological aspects of an eyesore in a blighted environmental area where you live and not feeling valued enough or people to acknowledge your concerns, health and welfare.
Thomas Rodgers owns Robertsons Billiards and Spas, a shop adjacent toU.S. Recycling. Dust clings to everything the fruit trees he planted, an old pool table, even the chickens that roam the side of his building. On recent afternoon, Rodgersbrushedthe fine gray powder from the ridges of his building.
Residents have also reported sludge coming from the access road and down Central Avenue toward storm drains that spill into Hog Creek. The Hog Creek watershed runs through Pioneer Park and dumps into Sarasota Bay right at Centennial Park, a popular recreational area.
However, environmental watchdogs and residents are concerned about the concrete washout potentially carrying toxic metal, according to the Environmental Protection Agency. It contains a PH level nearly twice the levels the agency considers safe. It can harm fish gills, eyes and interfere with reproduction.
Since 2016, officials from the city of Sarasota and Sarasota County have inspected the U.S. Recycling property almost a dozen times. Code enforcement and county environmental officials have marked these issues as unfounded and have even questioned whether there are any issues at all, according to records and interviews with residents.
Stewart visited the facility twice in January, attributing the issue to dust kicked up from the access road, records show. However, he did not indicate in thereport whether Williams had a permit for the concrete crusher.
In February, a joint inspection by local and state environmental officials revealed that U.S. Recycling was operating a concrete crusher without thestate-mandated air quality permit. Records show that Williams, the owner of U.S. Recycling, admitted to continuingusing the crusher, a machine that pulverizes concrete, even after officials told him to stop.
In April, residents reported to county environmental officials that large clouds of dust were coming from the U.S. Recycling facility. When officials showed up, Williams refused to allow a county inspector inside to look around, according to the inspection report. Williams reportedly demanded to know who was making complaints against him.
Robert Stewart, a county environmental official, warned Williams that by denying access, he was in violation of state law. Records show the county has yet to take enforcement actions in either of these cases.
Outside of U.S. Recyclings facility earlier this month, Williams briefly told a Herald-Tribune reporter that he believed that dust issues were caused by the poorly maintained access road that kicks up dust when semi trucks roll by. Williams declined to comment further.
The state agency is involved out of an abundance of caution and is conducting several tests of the air and groundwater. Environmental officials are also trying to determine whether the company needs a wastewater permit, as the facility is only a few blocks from Sarasota Bay.
I dont even get to use my backyard anymore, Stephens told commissioners in March. I have to plan my days around their days. When I say that, I mean if I want to cook out, I have to wait and see if there are any trucks coming back kicking up dirt, blowing it directly at my house.
Harry Owen owns a boat repair business that borders U.S. Recycling to the south. Owen said at a recent public meeting he has dealt with the dust fallout and health hazards for the last eight to 10 years.
Owen said that his merchandise frequently has to be cleaned of dust and that he has lost a substantial amount of money. He said he built his property in 2004 and followed the applicable zoning rules. He asked city commissioners: Why hadnt his neighbor?
I dont want to get into the specifics of where weve been, Robinson said. But as we move forward, were giving this 100% of our attention to try to bring this to a conclusion that both works for the community and U.S. Recycling.
The Central Cocoanut Historic District is just north of downtown. Although not historically an African American neighborhood, the majority of the residents are Black, despite recent demographic changes.
In 2003, FDEP found multiple environmental violations and fined Viera $4,200 for failing to clean up oil that leaked on the ground and for not properly labeling or storing hazardous materials such as batteries.
Records show that Viera dismissed efforts to recover penalties and failed to comply with corrective measures. In 2004, FDEP sued Viera in the 12th Judicial Circuit. It took five years and severallitigation efforts to finally force him to pay fines and produce a groundwater assessment study.
By 2007, Geologic and Environmental Testing Inc., the company hired by Viera to conduct the studies, found that contaminants had been released and that samples were shown to exceed the groundwater cleanup target levels for arsenic, chromium and lead.
Still, the assessment proved to be incomplete and when state officials demanded a more complete test, a representative from Geologic and Environmental Testing said that Viera had failed to pay him and cut all communications after he received the results, records show.
Environmental officials asked for additional testing in 2009, according to a letter from DEP to Viera and Joseph Spina IV, who would later take over the company. The state feared that arsenic contamination found in the groundwater could have potentially moved off site.
Freedom Estates financed the purchase with a $300,000 loan from hard-money lender Stephen Witzer. Williams, the owner of U.S. Recycling Company, would later take over Freedom Estates as title president.
State records show that there are five businesses operating out of the property: U.S. Recycling Company, Freedom EstatesInc., American Scrap Recycling CompanyInc., CRW Property Holdings Inc., U.S. Rock Company and United Scrap Recycling Company Inc.
According to the citys planning rules that govern neighborhoods, Sarasota is supposed to encourage planning that aims to strike a balance between residential and nonresidential uses. Its also supposed to discourage truck traffic on residential streets.
Residents have pointed out in public emails several alleged code violations, including that work being done on the property is generally required to be done within enclosed buildings. There is one partially enclosed building on the property.
The city of Sarasota is investigating whether U.S. Recycling and others who have owned the property have followed the citys zoning rules. It is also hoping to make road improvements on the access road to help mitigate pollution issues.
In the majority of pleural mesothelioma cases, doctors can link the diagnosis to on-the-job exposure to asbestos, a toxic mineral fiber. Occupational asbestos exposure was most common in miners, shipyard workers and factory workers.
According to World Health Organization estimates, approximately 125 million people face workplace exposure to asbestos worldwide. This exposure accounts for more than 100,000 occupational deaths per year from diseases like pleural mesothelioma, lung cancer and asbestosis.
Starting in the late 1800s, when Canadian companies first began mining asbestos on a massive scale, dozens of industries embraced the fibrous mineral for its natural resistance to heat, flame, electricity and chemical damage. These desirable qualities, in addition to its affordability, motivated companies around the world to incorporate asbestos into thousands of consumer and industrial products, including textiles, insulation and building materials. Prior to the 1960s, the public knew little to nothing about the potentially fatal consequences of asbestos exposure.
By the mid-1970s, approximately 200,000 Americans made their livings manufacturing asbestos products. Some of these workers handled the toxic mineral on a daily basis, often in poorly ventilated areas and without adequate safety equipment. Millions more worked in secondary industries regularly plagued by excessive on-the-job exposure, including shipbuilding, construction and automobile repair. According to one study, 27 million workers were exposed to airborne asbestos fibers in the United States between 1940 and 1979.
Thousands of these workers have developed related cancers including lung cancer and mesothelioma. Asbestos-related lung cancer accounts for 4% of all lung cancer cases in the U.S., and it is the most common asbestos-related cancer. Mesothelioma is the second-most common, and it is almost exclusively caused by exposure to asbestos.
Pleural mesothelioma, lung cancer and other asbestos-related diseases can arise when workers inhale asbestos dust. In certain occupational settings especially those where workers mine and process raw asbestos, manufacture asbestos-containing products or repair buildings or machinery with asbestos components the risk for harmful exposure is high.
While a dramatic reduction in asbestos use has reduced harmful exposure in industrial settings, construction workers continue to face serious exposure risks while repairing and demolishing asbestos-contaminated buildings.
Since the 19th century, extensive use of asbestos in factories, shipyards and dozens of other industrial settings has polluted countless job sites with airborne fibers. Activities like mining, pouring and mixing raw asbestos release deadly clouds of asbestos dust into the air. Workers have also suffered asbestos exposure while servicing asbestos-containing automotive brakes, cutting asbestos-coated cement pipes and applying spray-on asbestos fireproofing materials.
When workers perform tasks like these without taking proper safety measures as was often the case before the dangers of asbestos were widely known the microscopic fibers circulating in the air enter the lungs. Unlike some other airborne contaminants, the body has difficulty expelling asbestos fibers. The inhaled asbestos becomes trapped and accumulates in the lungs over time. The fibers can penetrate the lung tissue and enter the pleura, two layers of tissue that surround and protect the lungs.
As the fibers migrate about the lungs, they cause scarring that worsens over time and can severely impair breathing. Eventually, sometimes 10 to 50 years after the initial exposure, the asbestos can trigger genetic changes in the cells of the pleura that cause cancerous tumors to form.
Before federal organizations like the U.S. Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) enacted strict regulations on asbestos use, numerous industries hailed the material as a cheap, effective insulator and put it to extensive use. Manufacturers used asbestos to make numerous products ranging from gaskets and brakes to insulation, cement and drywall.
Workers who processed raw asbestos, manufactured asbestos products or worked with asbestos-containing materials were regularly exposed to the deadly fiber, generally without any knowledge of its cancerous health effects.
One of the most hazardous occupations in terms of asbestos exposure was mining. While all miners historically struggled with low pay and hazardous working conditions, the high risk for pleural mesothelioma and otherasbestos-related diseasesmade asbestos mining particularly dangerous.
In order to preserve the valued physical properties of asbestos, miners would excavate it dry a technique that amplified the amount of dust released into the air. Once the raw asbestos ore arrived at the mill, workers fed it into primary crushers where it was crushed and sorted. As the milling process continued, more and more dust was generated. One of the most dangerous steps was bagging, which involved pressing the fiber into burlap sacks by hand.
The use of asbestos aboard Navy and civilian ships exposed countless workers to the toxic mineral. According to Dr. Irving J. Selikoff, one of the first medical researchers to link asbestos to cancer, all U.S. merchant marine vessels built before 1975 contained extensive asbestos insulation materials. Shipbuilders sprayed asbestos onto bulkheads and deckheads and used the material to insulate pipes and machinery from bow to stern.
During World War II, the pressure to rapidly produce ships took precedence over the safety of workers. And the dangers of asbestos werent exclusive to shipbuilders. Other people who shared workspaces at the shipyards, such as electricians, faced exposure as well. Navy sailors and the crew aboard civilian ships also experienced considerable risks.Veteransof the Navy and other branches of the military faced regular asbestos exposure throughout their careers and often found work in other asbestos-reliant industries after serving their country.
U.S. Maritime Commission studies revealed that a ships motion at sea and engine vibrations causes asbestos materials to crack and flake. The agitation releases fibers into the air, and on-board ventilation systems circulate the dust to living quarters, mess halls and other ship compartments. In Selikoffs study investigating the asbestos-related lung injuries of more than 3,000 U.S. merchant marine seamen, researchers found that the most dangerous exposure occurred in the engine departments, decks and mess halls of ships.
In the first half of the 20th century, countless factories and industrial plants across the United States subjected workers to asbestos dust. Factory workers employed by asbestos manufacturing giants like Johns-Manville and Raybestos-Manhattan endured heavy exposure on a daily basis, as they often handled raw asbestos before it was processed into insulation, millboard, textiles and a wide range of other products.
Plenty of factory jobs not directly related to the asbestos industry were frequent sites of harmful exposure as well. Paper mills, textile mills, chemical plants and power plants all contained products or machinery that housed asbestos. Boilers, pipes and turbines housed asbestos insulation that would deteriorate over time and pollute the air.
Heavy occupational exposure to asbestos peaked in the 1960s and 1970s and declined in the years that followed as the government heightened workplace safety regulations. Since then, the industrial use of asbestos has significantly decreased.
Today, workers in the construction industry experience the heaviest exposure to asbestos. Tasks like maintenance, repair, renovation, demolition and asbestos abatement often put workers in contact with asbestos that is friable, or easily crumbled by hand. Compared with nonfriable asbestos, which poses minimal risks to health, friable asbestos can easily release fibers into the air. Nonfriable asbestos can become friable if it is crushed, sawed, sanded or disturbed in another way that releases dust.
Construction activities in older buildings are most dangerous since insulation and many other building materials manufactured before 1975 contain asbestos. While the government has phased out most asbestos-containing materials, asbestos can still be found in roofing materials, vinyl tile, cement pipe and corrugated sheeting. Workers must handle and dispose of these materials properly to ensure safety and avoid asbestos exposure.
According to the Agency for Toxic Substances and Disease Registry, the incidence of asbestos-related disease among occupationally exposed people is beginning to peak, and is expected to decline over the next two decades.
Snehal Smart is the Pleural Mesothelioma Centers in-house medical doctor, serving as both an experienced Patient Advocate and an expert medical writer for the website. When she is not providing one-on-one assistance to patients, Dr. Smart stays current on the latest medical research, reading peer-reviewed studies and interviewing oncologists to learn about advancements in diagnostic tools and cancer treatments.
Our Patient Advocates can answer your questions about mesothelioma, eligible treatment options, finding the best doctor and cancer center for your diagnosis, filing a VA claim, financial assistance as well as support and guidance for you and your loved ones.
Asbestos is a naturally occurring mineral composed of soft and flexible fibers that are resistant to heat, electricity and corrosion. These qualities make the mineral useful, but they also make asbestos exposure highly toxic.
Asbestos is an effective insulator, and it can be used in cloth, paper, cement, plastic and other materials to make them stronger. But when asbestos dust is inhaled or ingested, mineral fibers can become permanently trapped in the body.
Over decades, trapped asbestos fibers can cause inflammation, scarring and eventually genetic damage. A rare and aggressive cancer called mesothelioma is almost exclusively caused by asbestos exposure. Asbestos also causes other forms of cancer as well as progressive lung disease.
No amount of asbestos exposure is safe, but asbestos generally has the worst effects when a person is exposed to an intense concentration of it, or they are exposed on a regular basis over a long period of time.
Fibers are easily inhaled once they become airborne. It is important to avoid disturbing products that may contain asbestos. Additionally, people who live near naturally occurring asbestos deposits should avoid disturbing soil that may be contaminated.
The majority of patients with asbestos-related diseases are men in their 60s or older. This is because asbestos-related diseases have a long latency period, often taking decades to develop. They usually trace back to occupational exposure at workplaces historically staffed by men.
The Agency for Toxic Substances & Disease Registry shows about 27 million workers were exposed to asbestos between 1940 and 1979. Regulations have reduced the risk of exposure in the workplace, but a degree of risk remains for many occupations.
Living in the vicinity of an asbestos-contaminated mine or processing facility puts individuals at risk of environmental exposure. Asbestos industry work sites have existed across the United States, such as in the town of Ambler, Pennsylvania, and at landmarks such as Grand Central Terminal in New York.
For example, decades of vermiculite mining near the Superfund site at Libby, Montana, caused one of the worst environmental disasters in U.S. history. The ore contained traces of asbestos that contaminated the surrounding area for miles, eventually causing the deaths of hundreds of Libby residents.
Hundreds of manufacturers used asbestos insulation in steam engines, piping and locomotives. Thousands of other uses later emerged, and companies began putting it in products such as boilers, gaskets, cement, roofing materials and automotive brake pads.
Microscopic asbestos fibers cannot be seen, smelled or tasted. Unless it is clearly marked as asbestos, the only way to detect asbestos in an unmarked material is to send a sample to a lab for testing or hire an accredited asbestos inspector.
Some situations require the removal of asbestos-containing materials. But it may be safer to leave the materials undisturbed or encapsulate them with a sealant. Consult a certified asbestos abatement professional for the best advice.
Asbestos is not banned in the United States, but it is highly regulated. The asbestos industry has powerful lobbying organizations protecting its interests. The toxic mineral is still commonly used in Russia, China, India and Mexico.
From the beginning of the modern asbestos industry, doctors documented the lethal effects of asbestos exposure in scattered medical reports. As early as the 1930s, business executives also quietly researched the issue and found that asbestos exposure causes lung disease.
Asbestos companies made enormous profits by selling insulation to shipbuilders during World War II, and they expanded their business further during the postwar building boom. These companies even paid unscrupulous researchers, such as J.C. Wagner, who helped them deny any responsibility.
However, the publication of new information about asbestos and medical evidence linking the mineral to cancer could no longer be ignored. Labor unions began to fight back. American companies phased out most uses of asbestos in the 1980s, but it was too late for the workers who had been handling asbestos products for decades.
Former employees are filing lawsuits against asbestos companies, and so are the workers who used asbestos products on the job. Family members who develop mesothelioma through secondhand exposure are also eligible to file a legal claim.
Hundreds of thousands of patients and families have sought compensation for illnesses caused by the negligence of the asbestos industry. These claims hold the asbestos industry liable for the harm theyve caused and provide much-needed compensation to cover medical bills and lost wages.
You should see a doctor if you develop respiratory or gastrointestinal symptoms that progress and dont go away on their own. Tell your doctor about your history of asbestos exposure and ask them to screen you for related diseases. If you are diagnosed with mesothelioma, it is extremely important to get a second opinion from a mesothelioma doctor.
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Tina Giles Murphy, Stephen Bornstein, John Oudyk, Paul A Demers, A Quantitative Retrospective Exposure Assessment for Former Chrysotile Asbestos Miners and Millers from Baie Verte, NL, Canada, Annals of Work Exposures and Health, Volume 65, Issue 1, January 2021, Pages 113126, https://doi.org/10.1093/annweh/wxaa092
Despite numerous studies of asbestos workers in the epidemiologic literature, there are very few cohort studies of chrysotile asbestos miners/millers that include high-quality retrospective exposure assessments. As part of the creation of the Baie Verte Miners Registry in 2008, a two-dimensional job exposure matrix (JEM) was developed for estimating asbestos exposures for former chrysotile asbestos miners/millers. Industrial hygiene data collected between 1963 and 1994 were analysed to assess validity for use in a retrospective exposure assessment and epidemiologic study. Registered former employees were divided into 52 exposure groups (EGs) based on job title and department and mean asbestos concentrations were calculated for each EG. The resulting exposure estimates were linked to individual registrants work histories allowing for the calculation of cumulative asbestos exposure for each registrant. The distribution of exposure for most EGs (82.6%) could be described as fitting a log-normal distribution, although variability within some EGs (55%) exceeded a geometric standard deviation (GSD) of 2.5. Overall, the data used to create EGs in the development of the JEM were deemed to be of adequate quality for estimating cumulative asbestos exposures for the former employees of the Baie Verte asbestos mine/mill. The variability between workers in the same job was often high and is an important factor to be considered when using estimates of cumulative asbestos exposure to adjudicate compensation claims. The exposures experienced in this cohort were comparable to those of other chrysotile asbestos miners/millers cohorts, specifically Italian and Qubec cohorts.
The Hammer Mill is used either as a one-step primary crusher for reducing run-of-quarry material to as small as <1-in. size, or as a secondary crusher taking 4~8-in. primary-crusher product down to <-in. or finer. Its use as a rock crusher is almost wholly confined to the softer, easily crushable materials such as phosphates, gypsum, barite, asbestos rock, cement rock, and the like, medium-hard limestone being the hardest rock commonly crushed; as a secondary it is used for more abrasive material, especially if this is brittle, and scattered instances are reported of its use on siliceous gravels; in general, however, high maintenance is to be expected, if the siliceous content of a feed is in excess of 5%. The mill is particularly useful for clayey material that would clog reciprocating-type primary crushers. It also has wide use in crushing bituminous coal at coke-oven and power plants, and in disintegration, by shredding, of various fibrous organic materials such as plant stems (wood and straws), bones, and hoofs.
The Hammer Mill of which a number of different forms are shown below, comprises essentially a plurality of flailing hammers a which strike rock particles either when they are falling freely through air or as they rest on a stationary metal surface g inclined more or less in the direction of the hammer travel, and the struck particles, or fragments thereof, are thereupon, thrown with great force against other fixed surfaces k surrounding the flailing hammers, or are pinched at an angle between the moving hammers and fixed surfaces i usually perforate.
Machines of the general hammer mill type vary widely in details of construction, particularly as regards the conformation and material of the hammers, the placing and conformation of the breaker plates, the presence or absence of and the type of exit grating, and the position of the feed inlet. A typical medium-duty grate type machine is shown below, item A. The hammers a are suspended by pins b between heavy steel disks c, which are spaced along shaft d by suitable spacers and keyed thereto. The shaft d is carried in heavy bearings in the ends e of the main frame. A heavy flywheel is mounted on one end of the shaft; the other end is fitted with a drive pulley or is attached, through flexible coupling, directly to the driving motor. Rotation of the machine illustrated is counter-clockwise. The bottom of the feed hopper f carries heavy breaker plates, which may be moved forward, to compensate for wear, by suitable adjusting screws. A grid or screen for determining product size is formed by the longitudinal grate bars i. The top of the crushing zone is enclosed by an imperforate cover j. As the hammers wear beyond the limits of adjustment of the breaker plate g, they may be rehung further from the center of rotation, in other holes (l). In most forms of the hammer mill, the grid frame is also hinged (Items E and F) or otherwise arranged for gradual adjustment toward the center of rotation, as well as for dropping away for quick discharge of the load in case of a clog-up or sudden shutdown.
In some hammer mills (Type I) entering coarse material is first struck while partly supported against a stationary plate (Items A, E, G) and the hammers tend to drive broken fragments toward the grid; in others (Type II) entering material is first struck by rising hammers (Items B, D, F) and fragments are thrown against breaking elates along the top and down-coming sides, from which they bounce back into the hammer path for further blows before they reach the grid; and in yet others (Type III) the first blow is substantially horizontal (Items C, H, J, and, to a certain extent, in G), with some opportunity for reflection into the coarse-crushing zone before falling into the fine-crushing zone on the grid. The form I has heavy anvil bars carried on adjustable plates, so that the bars may be spaced at the most favorable distance from the hammers. On the grid the crushing action is, in part, simple impact against unbacked-up particles, and in part shear of pieces wedged between or lying upon the bars. Type I machines are medium-to light-duty; Types II and III heavy-duty.
The rotor is usually speeds up for such service, but, even so, there is no positive guard against discharge of oversize, and if a definite limiting upper size is important, the machine must be put in closed circuit with a screen. In secondary crushing and in pulverizing service a separate circuit-closing screen should always be used whether the machine contains a grate or not.
Tramp iron in feed is a source of grate-bar and hammer breakage, with possible resultant wreckage of the entire machine. Where possible, it is best removed by a magnet on the feed line. Some forms (Items G and H) provide a catch pocket a into which it is hoped the iron will be somewhat preferentially flung by centrifugal force and held for cleanout.
Main frame in large heavy-duty primary machines is made of deeply ribbed cast-steel sections with the main bearings and the bearings for the swing shaft for breaker plates and grid frame cast integral in a one-piece base. The upper housing is either cast or built up of plate and structural shapes. In either case flanged joints, carefully machined, are provided for bolting the housing to the frame. The hopper is made of rolled steel shapes and plates. In machines for lighter duty only the ends of the base are heavy iron or steel castings, with cast seats for the main bearings; rolled structural shapes and heavy plate are used for the balance of the frame and housing.
Housing should be kept down in size as much as is consistent with sufficient spacing of anvils or breaker plates. These latter are necessarily tough as well as hard; they consequently flow when worn unless properly backed. If the necessary backing is made an integral part of them, the discard is relatively enormous; hence either they, must be backed against the housing, or a special backing frame must be provided inside the housing.
Disks (Item A) are made of cast steel, with heavy hubs, bored and key-seated for the main shaft, and carefully bored in register with each other for the hammer-spending pins. They should be made without projections from face or edge essential to their functioning, as these wear excessively and thus shorten life. Designs that can be adapted to either stirrup or slugger hammers are useful.
Hammers are made of chilled iron, forged high-carbon steel, cast manganese steel, or special tough hard alloy steels, and in a variety of shapes according to service. They weigh from a few pounds to 250 lb. each.
Forms A, B, and C are BAR TYPE for light duty; A and C for relatively coarse product, B for a finer product produced by more attrition grinding on the grid. Forms D, E, and F are of the so-called SLUGGER TYPE, for heavy duty; in each of these forms some provision is made for saving discard metal.
Such forms are usually heat-treated to produce hard heads and tough shanks. Form E is cast with a cored-out head to permit compensation for wear by means of additions of lead in the cored cavity, with the idea of thereby decreasing troublesome and possibly destructive vibration due to uneven wear. In some forms, e.g., form F, the hole for the rotor pin is cored out for bushings of various eccentricities to permit maintenance of a relatively constant hammer circle, as a remedy to vibration. Form G has a replaceable head, designed to be pinned to the shank; this is better than similar forms with riveted heads, but the pins bend in service and are hard to remove; heads held on by lugs are better, if they are so designed as to insure against loss while running. Forms H and I are light and heavy STIRRUP TYPES respectively; they strike with greater impact than the slugger types, and are more effective in attrition grinding on the grid, but when they are forced back, more of the effective hammer circle is lost, and with them the rotor gets out of balance more frequently owing to uneven wear. A later form, designed with deeper sides, a bridge at the center, and with the face troughed, gave definitely longer life and lower metal costs per ton; the deeper sides increased the area of striking surface, which reduced both circulating load and wear on hammer arms; the bridge prevented deformation and thus made removal of worn heads a simpler and quicker job. The average new weight of heads was 28.6 lb. and the discard weight, 18 lb. If sides are made too deep for complete penetration, rejection weight increases owing to lack of wear at the inner portion. The trough reduced discard weight without reducing life. This change in design reduced metal cost for manganese-steel hammers and for chrome-steel. The essence of hammer design is to so apportion the metal that the head will maintain a face as large and as nearly in a radial plane as possible until wear has reached the point that breakage is imminent. With renewable tips, one shank will usually last as long as 3 or 4 tips.
Capacity of open circuits is decreased, and circulating loads in closed circuits tend to increase rapidly after the hammers are about half-worn, but the net reduction per hp-hr. is not greatly affected by hammer wear except near the end, provided penetration is complete.
A diagnosis of asbestosis, which is a long-latency, fibrotic lung disease, has implications for the patient in terms of prognosis, treatment and compensation. Identifying and quantifying asbestos exposure is difficult without a detailed occupational history, and the threshold dose of asbestos required to cause asbestosis is not well understood. We reviewed all cases of asbestosis diagnosed between 2001 and 2016 at the Birmingham Regional NHS Occupational Lung Disease Service to determine the industries and occupations most frequently implicated in causation, in order to help clinicians identify where asbestosis might enter the differential diagnosis for a patient with chronic respiratory symptoms. A variety of construction trades were frequently reported including carpenters and joiners, pipe fitters, laggers, labourers, painters and shop fitters. Traditionally heavily exposed occupations such as shipbuilding were not commonly seen.
Asbestosis is a diffuse interstitial fibrosis caused by inhalational exposure to asbestos after a latent period >20 years.1 It is a diagnosis made through a history of exposure, exclusion of other causes and the characteristic computer tomography (CT) appearances of usual interstitial pneumonia; that is, bilateral subpleural reticulation in a basal distribution, with bronchial dilatation and honeycombing.2 Current National Health Service (NHS) policy prevents prescription of antifibrotics for asbestosis3 though workers with confirmed asbestosis are eligible for state compensation.4 Thus, differentiating asbestosis from idiopathic pulmonary fibrosis (IPF) through exposure history is important but can be difficult, particularly because the dose of asbestos required to cause fibrosis is unknown.5 Heavy exposures as seen with asbestos miners, millers and textile workers has caused severe fibrosis with relatively short latency,6 but our current experience is one of asbestosis with comparatively lower exposures but longer latencies from work undertaken in the 19601970s, before the impact of UK regulations banning the import and use of asbestos.7 We aimed to identify the industries and occupations in patients diagnosed with asbestosis at a UK regional NHS occupational lung disease service to help clinicians identify those in whom a full exposure history is indicated.
There were 160 cases of asbestosis diagnosed between 1 January 2001 and 31 December 2015 [20012005 (34), 20062010 (35), 20112015 (91); median=10 cases per annum, interquartile range (IQR)=513]. Of 160 patients, 158 (99%) were males and median age at diagnosis was 74 (IQR=6979) with age distribution as follows: 5160 years (3%), 6170 years (33%), 7180 years (43%) and 8190 years (21%). At diagnosis 41 patients (26%) had asbestosis only, 117 (73%) had additional benign asbestos pleural disease (BAPD), 2 (1%) had mesothelioma (one with BAPD), and 2 (1%) had bronchial cancer (one with BAPD).
Commonly encountered industries and occupations are shown in Table 1. Construction was the commonest industry (44%) and most frequently identified across each 5-year period, becoming proportionally more common after 2005 (Fig. 1). Construction workers were most likely to be carpenters or joiners (12; 17%), laggers or laggers mates (10; 14%), painters or decorators (7; 10%), shop fitters (7; 10%), roofers (5; 7%), labourers (5; 7%), pipe fitters or fitters mates (4; 6%), plumbers (4; 6%), plasterers (4; 6%), floorers and tilers (4; 6%), sheet metal workers (2; 3%) or other (7; 10%). The two female patients were (1) a secretary from a British-based asbestos supply company and (2) a Portuguese civil servant now living in Britain, who worked in an asbestos mine near Chimoio in Mozambique between 1968 and 1972.
Common industries implicated in causation of asbestosis 20012016 at Birmingham Regional NHS Occupational Lung Disease Service. Construction was consistently the most frequently encountered industry during each 5-year period, becoming proportionally more common in 20062010 (p=0.02) and 20112016 (p=0.15) when compared to 20012005
A variety of trades within the construction industry were commonly responsible for exposure sufficient to cause asbestosis: particularly carpenters and joiners, laggers, painters and shop fitters. Pipe fitters, labourers, steel workers and welders were also frequently implicated, seen in a number industries (including construction). Work in naval engineering, train carriage manufacture and in power stations were also regularly encountered, but other traditionally heavily exposed UK occupations such as shipbuilding were not seen commonly.
Asbestosis was first described in the UK in 1924 in a 33-year-old female asbestos factory worker.8 Although further health risks of asbestos subsequently emerged, UK asbestos consumption increased throughout the twentieth century.9 Its properties of low cost, strength, flexibility and resistance to chemical corrosion, heat and fire made it desirable, particularly during World War II and the construction boom that followed. Consumption in the UK reached a peak in the 1960s, though the highest risk of asbestosis is observed 4060 years after first exposure;10 thus annual deaths and compensated cases have continued to increase year on year since 1978.11 In the UK, insulation workers followed by asbestos stripping/removal workers have the highest risk of asbestosis, followed by shipbuilders and construction workers.10
In this study, it is not possible to infer and quantify risk from employment without knowing when and how much exposure occurred or without population figures for the number of exposed workers at the time. Moreover, an increase in reported cases does not necessarily imply an increase in incidence of asbestosis, and other factors such as better and more frequent CT imaging, and the evolution of multi-disciplinary team decision making (i.e. physician, thoracic radiologist, etc.) may contribute to this. This is the experience of one regional UK centre and employment characteristics in other regions may vary, for example, one might expect to see more shipbuilders in Scotland and the North-East, where UK shipyards were concentrated, but not in the West Midlands. Indeed historically the West Midlands has seen lower rates of asbestosis than average for England, and significantly less than the North-West and North-East,11 suggesting different levels of exposure by region.
These results are broadly supported by studies which have shown heavy exposure and increased risk of lung cancer and mesothelioma in UK carpenters,12,13 thought to be due to the use of asbestos insulation board, and an increased risk in other construction trades (electricians, plumbers, pipe fitters and steel workers) elsewhere.14 A small number of workers in this study had co-existing thoracic malignancy at the time of diagnosis, though future risk of bronchial cancer and mesothelioma cannot be extrapolated from this data.
The advent of UK asbestos control legislation during the 1970s and beyond has resulted in lower workplace exposures to asbestos.15,16 The current trend of increasing incidence of asbestosis reflects the latency from previous heavy exposures. If, as the Health and Safety Executive (HSE) maintains, heavy asbestos exposures are required to cause clinically significant asbestosis during an exposed workers lifetime, one would predict a decline in incidence during the next decade.10 However, there is a strong association between asbestos imports and mortality from IPF, a disease whose incidence is rising. This is similar in magnitude to the association between asbestos imports and mesothelioma and this has raised an as yet unanswered question, about whether a proportion of IPF is actually asbestosis, caused by hidden or low-dose asbestos exposures.17
Asbestosis is an important diagnosis to suspect since the natural history may be different to IPF; there is an increased risk of mesothelioma when asbestos exposure has been recognized, and workers are eligible for state compensation. It is worthwhile considering asbestosis and referral for a full occupational history in patients who have worked in construction trades, presenting with chronic respiratory symptoms.
All cases of asbestosis diagnosed at the regional NHS Occupational Lung Disease Service in Birmingham, UK between 1 January 2001 and 31 December 2016 have been retained on a Microsoft Excel clinical database containing pseudo-anonymized data (by reference to hospital identification number only). These local data are used for monthly notifications to the UK Health and Safety Executive (HSE) national Surveillance of Work-related Respiratory Disease (SWORD) voluntary surveillance scheme for occupational lung disease.18 Diagnosis of asbestosis is based on exposure history and expert opinion on whether dose is sufficient to cause asbestosis, CT appearance and exclusion of other causes of usual interstitial pneumonia. From the database the following data were gathered, without recourse to individual patients medical records: age at diagnosis, gender, presence of additional asbestos-related diseases at diagnosis of asbestosis, and industry and occupation where exposure occurred. Descriptive analyses were performed; non-normally distributed data were displayed using median and IQR, and categorical data with percentages. Chi-squared testing at the 95% confidence level was used to look for significant differences between categories. The study was considered to be a service evaluation by UK Health Research Authority and Heart of England NHS Foundation Trust, and as such no ethical approval was sought.
Department for Work and Pensions (UK). Industrial Injuries Disablement Benefits: Technical Guidance. https://www.gov.uk/government/publications/industrial-injuries-disablement-benefits-technical-guidance (2013).
Wolff, H., Vehmas, T., Oksa, P., Rantanen, J. & Vainio, H. Asbestos, asbestosis, and cancer, the Helsinki criteria for diagnosis and attribution 2014: recommendations. Scand. J. Work.Environ. Health 41, 515 (2015).
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Walters, G.I., Robertson, A.S., Bhomra, P.S. et al. Asbestosis is prevalent in a variety of construction industry trades. npj Prim Care Resp Med 28, 11 (2018). https://doi.org/10.1038/s41533-018-0078-6Get in Touch with Mechanic