Contaminant of the month…Hormones

Contaminant of the month…Hormones

What it is:

  • Hormones are chemicals that act as signaling agents.  They are release in one part of an organism and transported to another part where they are recognized by a receptor and bind to the receptor, which results in a biological response.
  • There are endogenous hormones, synthetic hormone analogues and also exogenous chemicals(hormone mimics) that can have hormone-like effects from exposure.
  • Animals, humans and plants produce endogenous hormones.  Plant hormones are called phytohormones.
  • They can be effective at minute concentrations in the organism.
  • Hormones are selective, meaning that a specific chemical structure will bind to the appropriate receptor and result in a specific result.  However, some hormones can be effective to some degree across species and some chemicals are structurally similar enough to also bind to some degree.

Occurrence:

  • Environmental exposures to hormones and hormone mimics are usually very low; although many foods naturally contain phytohormone substances at substantial levels.
  • Total dietary intakes of phytohormones can be in the hundreds of mg a day.
  • Environmental sources (water) of hormones originate primarily from wastewater that receives natural and synthetic hormones that are excreted by humans.
  • Concentrations in wastewater and receiving water are in parts per trillion (ppt) or parts per billion (ppb) range.

Health effects:

  • There are concerns for the potential for health effects that could be caused by environmental exposures to actual hormones, synthetic hormones or chemical mimics.  The latter are often referred to as endocrine active chemicals.  Phenolpolyethoxylate detergents have some weak endrocrine activity.
  • Bisphenol; A (BPA) is a phenolic high volume industrial chemical that has major applications in production of epoxy resins that have numerous uses.  It has low hormonal activity.

Environmental effects:

  • Many hormones are not stable in the environment.  The estrogens and androgens are fairly stable and they have attracted much interest because they have been detected at ppt to ppb levels in receiving waters and source waters.
  • Feminization of fish has been observed in receiving waters of sanitary wastewater discharges.

Water treatment:

  • Conventional drinking water treatment appears to be effective for removing trace amount of steroidal hormones from drinking water.

Regulation:

  • The WHO has reviewed pharmaceuticals, including some hormones and concluded that risks from  drinking water exposure are very small and WHO guidelines are not required.
  • U.S. national regulations for drinking water are under consideration.
  • Several steroidal hormones and some potentially estrogen active synthetic chemicals are listed for monitoring by many drinking water supplies in the U.S. EPA Unregulated Contaminants Monitoring Rule (USMR 4) that is being developed.

Source: Biochemistry, 3rd Edition. G. Subay. Wm. C Brown publishers.  Pharmaceuticals in Drinking Water, World Health Organization, WHOoharmaceuticals_20110601.pdf.  Many food contain phytoestrogens, Academicsreview.org/reviewed-content/geneticroulette.