Enhancement of DMN-induced kidney tumors by 1,2-dichlorovinylcysteine in Swiss-Webster mice.

1,2-Dichlorovinylcysteine (DCVC) is known to cause enlarged nuclei in renal proximal tubule epithelium. This study further characterized the cellular changes induced by DCVC. Also a preliminary investigation of the initiator and promoter potential of DCVC was conducted.

RESPIRATORY SYMPTOMS AND SMOKING HABITS OF SENIOR INDUSTRIAL STAFF.

The prevalence of respiratory symptoms and the smoking habits of 224 industrial `executives' aged 30 to 69 years in Social Classes I and II were ascertained by means of the Medical Research Council's questionnaire on respiratory symptoms; 31% had persistent cough, 25% had persistent phlegm, and 21% were short of breath on hurrying or going up a hill; 9% had had one or more chest illnesses in the past three years lasting for about a week, and 4% had `chronic bronchitis'—defined as persistent phlegm and one or more chest illnesses in the past three years; 67% were smokers, 21% smoking more than 25 cigarettes (or equivalent tobacco) per day; another 20% had stopped smoking. The prevalence of cough, phlegm, and breathlessness was closely related to smoking habit. Data for those aged 40 to 59 years are compared with that obtained from London Transport Board workers and a sample of the population studied by the College of General Practitioners.

HEALTH EXAMINATIONS OF SENIOR STAFF IN INDUSTRY.

Of 228 senior staff participating in schemes for their health supervision who were asked for their opinions on the examinations, 26% said they had derived a lot of benefit, 53% a little, 20% no benefit, and 1% were unable to express an opinion. The degree of benefit felt was influenced by the number of routine examinations; age was relatively unimportant. Detection of hidden illness was considered the most important objective of the examinations, and the value of reassurance, usually in the absence of abnormal clinical findings, was mentioned by 65% of the respondents.

A STUDY OF BYSSINOSIS, CHRONIC RESPIRATORY SYMPTOMS, AND VENTILATORY CAPACITY IN ENGLISH AND DUTCH COTTON WORKERS, WITH SPECIAL REFERENCE TO ATMOSPHERIC POLLUTION.

An epidemiological survey of 414 English and 980 Dutch male cotton workers was undertaken to determine the prevalence of byssinosis and respiratory symptoms, and to compare the ventilatory capacities in the two populations, with particular reference to the influence of air pollution. The English workers were employed in six mills in Lancashire and the Dutch workers in three mills in Almelo spinning similar grades of cotton. The methods used included a questionnaire on respiratory symptoms and illnesses, the collection and examination of sputum, and the measurement of the forced expiratory volume over 0·75 sec.