Endocrine disruptors

Question 1

Endocrine disrupting chemicals (EDCs)

Answer 1

Endocrine disrupting chemicals (EDCs) = exogenous agents that interfere with the production, release, transport, metabolism, binding, action or elimination of bodily hormones.
* Includes: BPA (e.g., plastic bottles / packaging), PCBs, phthalates (e.g., beauty products), heavy metals (e.g., lead, arsenic, mercury), pesticides and herbicides, fire retardants, dioxins, drugs (e.g., NSAIDs). Tap water (contains many of the above).

Question 2

EDCs: Mechanisms

Answer 2

‒ Alter hormone receptor signalling and sex
hormone production, secretion and metabolism.
‒ Induce oxidative stress, mitochondrial damage and epigenetic alterations (DNA damage and chromosome alterations).

Question 3

EDCs: Adverse health effects

Answer 3

Increased risk of cancer, hormonal disorders such as PCOS, early puberty and gynaecomastia; infertility, cognitive deficits and obesity.
* Critical window of susceptibility: In utero, neonatally, in childhood and puberty

Question 4

Xenoestrogens

Answer 4

Xenoestrogens = a sub-category of EDC that are structurally similar to oestrogen and can bind to oestrogen receptor
sites with potentially hazardous outcomes.
* Examples: Pesticides, herbicides, dioxins, parabens, BPAs, phthalates, preservatives. Tap water (chlorine, pharmaceuticals etc.)
* Bioaccumulation: Build up in the fat of meat / fish, dairy products and in human fat cells with age.
* Exposure: Mainly by ingesting via food and
drink. Small amounts may be inhaled or
absorbed through the skin and mucous membranes.

Question 5

Dairy

Answer 5

Dairy — commercial milk is mostly derived from pregnant cows, with increased hormone concentrations in the third trimester.
* E1, E2 and E3 steroid hormones are found in all milks, with a higher concentration in whole milk. Choosing raw or organic milk will make little difference to hormone content.
* Dairy products also contain other hormones, including IGF, PCBs, dioxins, insecticides, bovine growth hormone
(use of growth hormones is banned in EU / UK).
* Whilst amounts are deemed safe, they add to the overall oestrogen load and, therefore, should be avoided in hormonal imbalances.