There are many compounds in the human environment that can impinge on the action of endogenous estrogens that are naturally occurring in the body. These compounds are referred to as xenoestrogens or endocrine disrupters. Their characteristic feature is modulation of endocrine pathways by interacting with the same estrogen receptors due to structural homology as physiological estrogens. A separate class of xenoestrogens are compounds that, although they have a different structure, may also interact with the estrogen receptor but through other mechanisms. Such compounds are called metalloestrogens, one of them is chromium. This applies to both hexavalent Cr (VI) and trivalent Cr (III) chromium. Exposure to Cr (VI) is associated with environmental exposure and development, and Cr (III) mainly with its widespread use in the form of dietary supplements, multivitamin supplements or sports nutrition. Therefore, this element can play an important role in inducing endocrine disorders. In addition to the receptor mechanism associated with displacement of zinc ions from the zinc-estrogen receptor fingers, chromium ions also show activity in the induction of oxidative stress, the production of free radicals and reactive oxygen species, and damage DNA. In this article, based on available literature, the mechanisms of xenoestrogens and metalloestrogens have been presented, including chromium, which occurs in the body at various degrees of oxidation, as well as their effect on modulation of endogenous estrogen pathways.

Keywords: chromium, estrogens, metalloestrogens, endocrine disruptors.