Pitch workers

Coaltar Lung, larynx, skin, bladder Gas house workers, coke oven workers, coal tar and pitch workers... 

Some pitch components that are soluble in sebum can stimulate epithelial cell production. Hair follicles and sweat-gland openings can be mechanically plugged by the CTP particles and by the resulting cell proliferation. Secondary retention of sebaceous material, pustule formation, and inflammation often result (Schwartz et al. 1957). Acneiform lesions were much more common in pitch workers (93%) than in controls (31%) with a peak incidence of these lesions in the 40-to 49-year-old age group (Hodgson and Whitely 1970). 

In pitch workers, pure comedonal acne develops on areas such as the face and neck, which are exposed to fumes but not to friction whereas, folliculitis, characterized by papules and pustules, most often occurs on the thighs, forearms, and back, where there is friction and occlusion from clothing in addition to pitch exposure (Crow 1970 T.F. Downham, unpublished observations). Other authors observed that even pilo-sebaceous follicles on the proximal phalanges and thumb webs can be covered by black comedo-like plugs (Ross 1948 Combes 1954). Pitch acne usually clears quickly and results in minimal scarring however, it is not uncommon for pitch workers to have a few persistent comedones which, despite regular extraction, still reappear even 10 years later (Crow 1970). 

Cysts filled with sebaceous and keratinaceous debris have also been described (Ross 1948). Crow found that straw-colored cysts, which were typical of chlor-acne, were rarely seen in pitch workers (Crow 1970). In a different series, sebaceous retention cysts and... 

Papillomas generally result between 6 months and 43 years after exposure. The shiny and sessile lesions mainly occur on exposed skin of the hands and forearms. Interestingly, there were more benign papillomata in their control group (73%) than in the pitch workers (58%) (Hodgson and Whitely 1970). 

The earliest lesions that can be detected after only a few months of exposure to pitch are small raised, flattened keratoses (1-5 mm) on the dorsal aspects of the hands, forearms, or face. These lesions may resemble flat warts and are usually stable over many years. Rarely, hypertrophic growth may result in formation of cutaneous horns (Ross 1948). Pitch keratoses (squamous keratoses) were slightly more common in pitch workers -12% compared with 10% in the control group (Hodgson and Whitely 1970). 

Thirteen and one-half percent of pitch workers had proliferative scrotal lesions, of which 3.5% had keratoacanthoma and one worker had squamous cell carcinoma (SCC). Velvety scrotal plaques found in 4.2% were associated with proliferative lesions caused by pitch elsewhere and may have been the result of friction and/or chemically induced inflammation. All of the workers with the velvety scrotal plaques had presented with keratoacanthomas elsewhere, and five showed evidence of other chronic CTP dermatoses. All diagnoses of scrotal lesions were made clinically without biopsy confirmation (Hodgson and Whitely 1970). 

In one study, basal cell carcinomas only occasionally occurred in pitch workers (0.7%), in sharp contrast to a much higher rate observed in the control population (12.5%) (Hodgson and Whitely 1970). 

Hodgson GA (1973) Pitch worker s skin. Br J Dermatol 89[Suppl 9] i05-i07... 

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