Chimney sweeps

In 1775, the British surgeon Sir Percivall Pott suggested that scrotal cancer in chimney sweeps was caused by soot. This was the first proposal that cancer could be caused by chemicals present in the workplace. 

Man has served as the unintentional guinea pig for the identification of some major classes of carcinogens. These include the polycyclic aromatic hydrocarbons (PAH), or polyarenes, which have been identified as the active components of soot, which was recognized by the London surgeon Percivall Pott two centuries ago as responsible for cancer of the scrotum in chimney sweeps. Subsequently, polycyclic hydrocarbons have been implicated as agents responsible for skin cancer in other occupations such as shale oil distillation and mule spinning in the cotton industry. 

Modem toxicology has its roots in the occupational environment. The earliest recorded observations relating exposure to chemical substances and toxic manifestations were made about workers. These include Agricola s identification of the diseases of miners and Pott s investigation of scrotal cancer incidence among chimney sweeps. Occupational toxicology, as its name implies, concerns itself with the toxicological implications of exposure to chemicals in the work environment. 

Sir Percival Pott published in 1775 the first record of occupation-ally related human cancers this London physician recognized the link between cancer of the scrotum and the occupation of chimney sweep. More of Sir Percy s work will be described in Chapter 5. 

Because adverse skin responses are so easily recognizable, this organ was among the earliest subjected to scrutiny, mostly by physicians interested in occupational diseases. Bernardino Ramazzini s tract of 1700, De Moribis Artificum Diatriba, contained many examples of skin diseases associated with occupational exposures, and, as will be seen in the next chapter, the seminal work of Percival Pott on occupationally induced cancers, published in 1775, revealed the role of soot in the production of cancers on the skin of the scrotum in London chimney sweeps. 

Human cancers were much discussed by Galen and most medical commentators ever since, and dozens of hypotheses regarding the origins etiologies) of these diseases are recorded in the medical literature. A seminal event relevant to our present concerns about the environment occurred in 1775. A British surgeon, Percival Pott, published his observations on high rates of cancer of the scrotum among London chimney sweeps. Pott attributed the cancers to the soot with... 

Another type of biological evidence that supports a case for causation derives from experimental work with animals if the substance under consideration is carcinogenic in animals, associations seen in epidemiology studies become biologically supportable. Sometimes it is possible to conduct a study after intervening to remove the suspect substance if risk declines following such an intervention, the case for causation strengthens (recall Pott s chimney sweeps). 

The history of the relationship between environmental agents and cancer is a long one. To begin with, the British surgeon Percival Pott noted in 1775 that young boys employed in London as chimney sweeps suffered an abnormally high frequency of scrotal cancer. Clearly, there was something in the coal tar to which they were exposed in their miserably filthy work that elicited this cancer. 

The first description of an occupational cancer was made by a British surgeon, Percival Potts in 1775. This was cancer of the scrotum in young chimney sweeps in the 18th century in Britain. Many young boys, who were small enough to climb up chimneys, were employed to remove the soot. They probably worked whilst clad in very few clothes so that there would be frequent damage to the scrotum which, with direct exposure to soot, could lead to the development of cancer, which was known as chimney sweep s cancer or epithelioma of the scrotum. 

Percivall Pott made one of the first observations of a health risk related to occupational exposure. In 1775, he noted that chimney sweeps had a higher incidence of cancer of the scrotum. A century later, in 1895, it was observed that workers in the aniline dye industry were more likely to develop bladder cancer. 

In 1775, Pursevil Pott first noted that the compounds associated with soot caused scrotal cancer in British chimney sweeps (] ). Not having modern methods of Instrumental analysis available to him, Pott was unable to specify the chemical structures of these compounds. It remained until 1933 before Cook et al. identified the exact structure of benzo[a]pyrene and demonstrated its carcinogenicity ( ). Thus, polycyclic aromatic hydrocarbons (PAH) are one of the few groups of compounds which are known to be carcinogenic to man. 

Although there are few chimney sweeps in business today, people are still exposed to considerable amounts of polycyclic aromatic hydrocarbons. Cigarette smoking, for example, is a major source of PAH ( ) coke production also has high PAH emissions (O. 

Percival Pott proposed that the high rate of cancer of the scrotum incurred by London s chimney sweeps was due to the presence of certain chemicals in the fireplace soot (i.e., POM) to which they were heavily exposed (Pott, 1775). Some 150 years later, Passey (1925) reported that organic extracts of such domestic soot induced tumors in experimental animals. 

Sal ammoniac (ammonium chloride) had been known from antiquity, it being easily obtained by sublimation from animal refuse (urine) and from coal soot, chimney sweepings, etc. Its virtues seemed to lie in its volatility, that is its spirituality. Here are a few remarks from Lemerys book. 

Cancer was first recognized as an occupational hazard in 1775 when the prevalence of scrotal cancer among London chimney sweeps was noticed. The chemical origin of this form of cancer was not universally accepted until 1922 when it was demonstrated that tumors could be induced on mouse skin using an etheral soot extract (60). Skin cancer was also noted to be an occupational hazard of workers exposed to pitch dust in the coal-briquetting industry (61) and to workers exposed to cmde tar (62). In 1915, tumors were produced in rabbits ears by prolonged application of cmde coal tar (63). Some 38 cases per year have been reported of cutaneous epithelioma in the tar distilling industry over a 25-year period up to 1945 (64). 

Probably the earliest such observation was by Sir Percival Pott, an English physician, in 1775. He noted that chimney sweeps, who tended to suffer from scrotal cancer, were also exposed to soot and tar. He correctly connected these two events. More recent research confirmed that coal tar and the aromatic hydrocarbons it contains will cause cancer of the skin in experimental animals. 

In contrast to the high degree of specificity of oestrogen receptors, the receptors for androgens are not as well-defined. Nevertheless, a paper published in London more than 200 years ago [492] reported that a high incidence of cancer of the scrotum and testicles was detected among chimney-sweeps. This disease could be associated with the chronic contact with soot. It is well known that the androgen, testosterone, is formed and accumulated mainly in the testes. 

There were some important developments during the eighteenth century. Probably the best known is the publication of Ramazini s Diseases of Workers in 1700, which led to his recognition as the father of occupational medicine. The correlation between the occupation of chimney sweeps and scrotal cancer by Percival Pott in 1775 is almost as well known, although it was foreshadowed by Hill s correlation of nasal cancer and snuff use in 1761. 

Two of the earliest observations that exposure of humans to certain chemicals or substances is related to an increased incidence of cancer were made independently by two English physicians, John Hill in 1771 and Sir Percival Pott in 1776. Hill observed an increased incidence of nasal cancer among snuff users, while Pott observed that chimney sweeps had an increased incidence of scrotal cancer. Pott attributed this to topical exposure to soot and coal tar. It was not until nearly a century and a half later in 1915 when two Japanese scientists, K. Yamagiwa and K. J. Itchikawa, substantiated Pott s observation by demonstrating that multiple topical applications of coal tar to rabbit skin produced skin carcinomas. This experiment is important for two major... 

Eric J. Hall (1998) From Chimney Sweeps to Astronauts Cancer Risks in the Workplace... 

Percivall Pott, 1775 born in 1714 and apprenticed to Edward Nourse, made some groundbreaking discoveries in the fields of cancer research and surgery techniques. He discovered the link between occupational carcinogens and scrotal cancer in chimney sweeps and wrote multiple scientific articles in his lifetime. 

Cancer, in fact, has afflicted humans around the world and throughout recorded history. The origin of the word cancer is credited to the Greek physician Hippocrates (460-370 Bc), considered the father of medicine. Hippocrates used the terms car-cinos and carcinoma to describe non-ulcer-forming and ulcer-forming tumors. Bernardino Ramazzini, an Italian doctor, reported in 1713 the high incidence of breast cancer in nuns. Percival Pott of Saint Bartholomew s Hospital in London described in 1775 an occupational cancer in chimney sweeps, cancer of the scrotum, caused by soot collection under the scrotum of workers. 

As men and women can spend up to a third of their lives at work, what they are exposed to in the workplace is of great importance. One of the first diseases that was clearly recognized to be due to an occupational hazard was cancer of the scrotum, which occurred in chimney sweeps. This was first recognized and described by Sir Percival Pott in 1775. It was, apparently, due to the exposure to soot and coal tar. It was not until much later (in 1916) that it was shown experimentally that coal tar could cause cancer in rabbits exposed to it. In many cases of industrial diseases resulting from exposure to chemicals, especially in earlier times, the association has been made by studying populations (epidemiology), while the basic experimental work has provided the evidence only later. 

In England in 1775, Dr. Percivall Pott wrote a paper on the high incidence of scrotal cancer in chimney sweeps who were typically boys small enough to fit inside chimneys and clean out the soot. Pott suggested that chimney soot contained carcinogens that could cause the growth of the warts seen in scrotal cancer. Over a 150 years later, chimney soot was found to contain hydrocarbons capable of mutating DNA. 

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