The prevalence of varicose veins was studied in 504 women cotton workers in England and 467 in Egypt, by a standardized questionary and a specially developed method of examination. The English mill population showed a much higher prevalence of varicose veins than the Egyptian, probably owing to environmental rather than ethnic reasons.Among the European women the prevalence of varicose veins was significantly related to age, parity, body weight, type of corsetry, and occupation-that is, whether or not they stood at their work. After standardizing for the other variables there was a statistically significant excess of varicose veins in women wearing corsets and roll-ons compared with those wearing less-constrictive garments. After a similar standardization a significant excess was found in women who stood at their work compared with those whose jobs entailed walking or sitting.

1969). Brit. J. industr. Med., 26,[202][203][204][205][206][207][208][209][210][211][212][213][214][215][216]. An investigation of lead absorption in an electric accumulator factory with the use of personal samplers. Thirty-nine lead workers and controls, in stable conditions of exposure, each wore personal lead-in-air samplers daily for two weeks. During the second week samples for blood lead, urinary lead, urinary coproporphyrin, urinary 8-aminolevulinic acid (ALA), the punctate basophil count, and haemoglobin were taken daily. Duplicate estimations were made on one day.The lead exposures of men doing almost identical jobs differed by ratios of up to four to one. This could be attributed only to personal differences in working habits.The correlation coefficients and regression equations of the biochemical tests with lead-inair and with each other were determined. The-mean values and 95 % confidence limits of single determinations of some of the biochemical tests corresponding to the two commonly accepted TLVs of lead-in-air (0-20 and 0 15 mg./m.3) were calculated from the regression equations.For each biochemical test the variation due to analytical error, the variation from day to day within subjects and the residual variation about the regression on lead-in-air were calculated. Previous estimates of the latter are not known. Excessive confidence may be placed in an index of exposure due to its low coefficient of variation within subjects unless the coefficient of variation between subjects about regression is taken into account.The correction for specific gravity of estimations of lead and ALA in spot samples of urine was found to reduce slightly the residual variation between subjects about the regression on lead-in-air and to increase the correlations with lead-in-air and with the other biochemical tests, but these changes were not statistically significant.The modified method used for estimating blood lead and urinary lead is described and validated.

M. (1969). Brit. J. industr. Med., 26,[121][122][123][124][125]. Circadian variation of F.E.V. in shift workers. The one-second forced expiratory volume (F.E.V.1.0), the forced vital capacity, and the oral temperature were measured in a group of men working a rotating three-shift system-2 to 10 p.m. one week, 10 p.m. to 6 a.m. the next week, and 6 a.m. to 2 p.m. the third week. The outside air temperature at the London Weather Centre was also obtained. Measurements were made on Mondays and Fridays at the beginning, middle, and end of the shift.The mean F.E.V.L.O of 19 normal men showed an increase of 0 15 litre (4-1 %) between the beginning and end of both the morning shifts, a mean decrease of some 0 05 litre (1I5 %) between the beginning and end of the afternoon shifts, and little change during the night shifts. This circadian variation could not be attributed to industrial fume, smoking or a learning effect.The findings will be of practical importance when F.E.V. is measured in shift workers to determine the effects of toxic substances on ventilatory capacity.Previous studies indicate that there is a circadian variation of ventilatory capacity (Lewinsohn, Capel, and Smart, 1960;McDermott, 1966; McKerrow, McDermott, Gilson, and Schilling, 1958;Bouhuys, Hartogensis, and Korfage, 1963; Walford, Lammers, Schilling, van den Hoven van Genderen, and van der Veen, 1966). A survey of the forced expiratory volume of a group of men working a rotating three-shift system has been made in order to obtain more precise information. Oral temperature was also measured to determine whether there is an association between the circadian variation of oral temperature (e.g., Kleitman, 1963) (174 cm.), with a range of 5 ft. 3 in. (160 cm.) to 6 ft. 5 in. (196 cm.). All the men were Caucasians.