Public health has received more attention than occupational health. Since entire populations were vulnerable, including the affluent, interest in communal health preceded that of issues relating to specific trades. The importance of sanitation and clean drinking water were recognized early on but this was largely lost in the Middle Ages. Epidemics were the subject of fear and the concept of spread of contagious disease is very old. However, there were many wrong hypotheses concerning how disease was transmitted and what the harmful agents underlying infection disease actually were. The causality of disease remained speculative until the identification of bacterial pathogens. Large numbers of workers in relatively small spaces, all exposed
to similar hazards, allowed epidemiological conclusions to be drawn.
There exist good descriptions that were assembled in the nineteenth century, of characteristic ailments relating to exposure to coal tar, silica dust, cotton dust, and aniline dyes. Later on quantitative evidence for harmful nature of several chemicals and radiation was collated. More recently, human toxicity of pesticides, solvents and a range of metals have been documented using health data derived from an occupational setting. Both communal and workplace health have been adversely affected by the neglect of old knowledge. Important information is identified, disseminated and then forgotten, sometimes for centuries, until it is once again rediscovered.
Last date updated on June, 2014