A seasonal variation in the excretion of phenols.

Abstract

By total urinary phenols we mean substances which react with the reagent in the Folin and Denis colorimetric method. The subject studied in this experiment abstained from meat, fish, coffee, tea, alcohol and tobacco; an average figure was taken for a four day sample during such weeks in which there was no sickness, accident or vacation.

Although the level for 1923 is higher than that for 1924, yet, within each year we find about 100 mg. more phenols excreted per day during the summer months of June, July and August, than during the winter—meaning December, January and February; the spring and autumn show intermediary figures, and those for the autumn would probably have been higher had not September been vacation-month. If we combine the two years of 1923 and 1924, we find the following:

Spring, 60 days, average 411 mg.;

Summer, 71 days, average 463 mg.;

Autumn, 60 days, average 388 mg.; and, finally, Winter, 84 days, average 345 mg.; or for 3 winters, 124 days, average 353 mg. of phenols.

As to the cause of such a seasonal variation we at first thought that the analyses were perhaps carried out at somewhat higher temperatures during the summer and that this might be a factor. Tests showed that a standard set at 20° Centigrade compared with a similar standard set at 30° Centigrade gives an increased color in the latter equivalent to a 20 per cent error; however, a certain sample gave 333 mg. of phenols at 30° Centigrade and 338 at 20° when compared with the same standard at the corresponding temperatures. We always kept the standard and the unknown at the same temperature, so this error was not introduced.

Secondly, because the phenols in an exaggerated manner followed the Nitrogen fluctuations of 1924-25, we have included the records of the winter 1925-26, which demonstrates that Nitrogen is not the main factor; for with 12.66 g of N per day for the winter against 21.75 for the summer, the phenols remain low.