In 1882-1883 James Longmore from Liverpool took several patents on separating the colorant by partial saponification of the oil,[3][4] and in 1886 he presented his findings to the local section of the Society of Chemical Industry.

[7] F. E. Withers and F. E. Caruth first attributed the toxic properties of the cotton seed (known since the 19th c.) to gossypol in 1915,[8] and its chemical formula was established in 1927 by Earl Perry Clark (1892-1943).

[12] A 1929 investigation in Jiangxi showed correlation between low fertility in males and use of crude cottonseed oil for cooking.

They concluded that gossypol provided reliable contraception, could be taken orally as a tablet, and did not upset men's balance of hormones.

The studies also discovered an abnormally high rate (0.75%) of hypokalemia (low blood potassium levels) among subjects.

The same study showed taking potassium supplements during gossypol treatment did not prevent hypokalemia in primates.

[16] In addition to the other side effects, the WHO researchers were concerned about gossypol's toxicity: the LD50 in primates is less than 10 times the contraceptive dose,[14] creating a small therapeutic window.

This report effectively ended further studies of gossypol as a temporary contraceptive, but research into using it as an alternative to vasectomy continues in Austria, Brazil, Chile, China, the Dominican Republic, and Nigeria.