Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/581365
AGGREGATES MANAGER October 2015 44 by Bill Langer Bill Langer is a consulting research geologist who spent 41 years with the U.S. Geological Survey before starting his own business. He can be reached at Bill_Langer@hotmail.com In Stone B y 1892, Barre granite had become a premier stone for monuments, mausoleums, and gravestones. PneuRockmatic machinery was introduced to help meet the skyrocketing demand. Along with pneumatic machinery came dust and silicosis. Silicosis plagued the Barre granite cutters who worked in the manufacturing sheds during the first few decades of the 20th century. Doctors and laymen alike had long recognized dust as a problem for granite cutters and other dusty trades, but, ironically, a major medical breakthrough confounded the discussions about phthisis (lung disease) in granite cutters. During the 1870s, the work of Louis Pasteur brought microscopic bacteria and germs to the attention of the medical community. Robert Koch, a German physician, followed his lead and, in 1882, he discovered Mycobacterium tuberculosis, the bacterium that causes tuberculosis (TB). Koch's discovery led to almost universal agreement among American medical personnel that germs, not dust, caused phthisis. All cases of lung disease suddenly were diagnosed as TB. Researchers mocked the theory of quartz lungs, and, in the U.S., the study of industrial causes of phthisis ceased. Many granite cutters, including shed owners who worked alongside them, accepted the medical opinion that their illness was a form of TB caused by germs from unsanitary practices at work and home. Support of the biological cause of phthisis continued into the mid 1920s. But beginning in 1912, British investigators published a series of papers documenting that non- infectious cases of phthisis could occur when tuberculosis was grafted onto a fibroid growth in the lung originally caused by dust. Unfortunately, many of their reports did not reach American researchers. Around 1922, the U.S. Bureau of Labor Statistics (BLS) published a report that concluded phthisis from exposure to dust was distinct from TB and was caused by the inhalation of minute particles of silica. Insurance company statisticians reported that exposure to dust from silica- rich rocks such as granite produced a statistically significant predisposition to phthisis whereas dust from limestone did not. The BLS admonished the medical community for focusing on bacteriological causes of phthisis and ignoring workplace related causes. Concurrently, D.C. Jarvis, a doctor practicing in Barre, observed that granite cutters' phthisis was not recognized by local doctors. He endeavored to convince both physicians and granite cutters that the disease was caused by work in a dusty environment, not from biological sources. Meanwhile, the workforce of skilled stonecutters was being greatly impacted through the silicosis-based deaths of some of its most skilled and senior workers. Those workers not only left the workforce prematurely, but were unable to mentor apprentices. Immigration quotas passed during 1917, 1921, and 1924, greatly complicated the ability of shed owners to replenish the workforce with skilled stonecutters from Europe. With a clearer understanding of the causes of stonecutters' phthisis, and faced with a shortage of workers, shed owners looked in earnest for means to protect their workers from the harmful effects of dust. During the 1920s and 1930s, they introduced dust control methods including sweeping the floors, wearing masks, and the installation of what turned out to be ineffective ventilation equipment in the sheds. More efficient dust control systems were developed, and during 1936, an agreement was reached that required all manufacturing sheds to install effective suction equipment on all dust-generating machines. There have been no silicosis deaths in Vermont granite industry workers that were hired after 1940. The discovery of the bacteria that causes tuberculosis set safety precautions back by nearly 50 years. SILICOSIS Combating Monument of Louis Brusa, a Barre sculptor, and his wife, Mary. Brusa died of silicosis.