46 PITCH INDUSTRIES AND CANCER 



tracted. Extracts of washed pitch so treated no 

 longer induced cell-division or excitation. 



The question whether pitch from tar so treated 

 is no longer dangerous can only he answered hy 

 the use of such pitch (provided it is still suitable 

 for the manufacture of fuel) in briquette works 

 for a period of several months, to see if the 

 incidence of warts, ulceration, and epithelioma 

 is reduced. Unfortunately, the Home Office 

 Regulations, if imposed, would render fallacious 

 such an experiment, because it would be im- 

 possible to ascertain whether any amelioration of 

 the incidence of cancer if such occurs is due 

 to the use of pitch made from the so-treated tar, 

 or to the bathing accommodation and overalls 

 supplied for the workmen. In our opinion the 

 Regulations, which are based on the obvious 

 principles of hygiene and cleanliness, are very 

 necessary, but it might be of great value to 

 cancer research if it could be definitely ascer- 

 tained before the Regulations were imposed 

 whether the dangerous principles can be effectively 

 removed from the tar or pitch. An inquiry is 

 to be held on the subject shortly, to consider 

 some objections to the Regulations raised by the 

 Patent Puel Companies ; and it is possible that 

 this experimental corroborative evidence as to 

 there being cell-division-inducing agents in the tar 

 and pitch may be useful to the parties concerned. 



Since the above was written we have heard that 

 the inquiry stands adjourned for some time owing 

 to strong objections raised against the Regulations. 

 This will give us an opportunity to see if the 



