Toxins Affect Endocrine Function

Every day, more than 82,000 chemicals are released into our air, water, soil, food and consumer products (1,2). Chemicals are not well regulated, and only a fraction of them have been tested for toxicity (2). Thus, we know little about the long-term consequences (3) of these pervasive pollutants.

We do know that since industrialization, medical conditions related to bioaccumulative toxicants have paralleled production of these synthetic chemicals (1,4). The effect of toxins on reproductive and endocrine function is particularly disturbing. For example, we now recognize metal contaminants that change hormones and alter menstruation, ovulation and fertility (5) can also affect a human’s entire lifecycle, starting at preconception. Fetuses, infants and young children are the most susceptible to harmful chemical influences on their hormones (3).

Hormones are biochemical messengers with a significant role in managing growth, energy metabolism, fertility, as well as influence the immune system and behavior. Through communication with the brain, endocrine glands produce, store and secrete hormones throughout the body (6).

Chemicals that interfere with hormone production, metabolism and function are called endocrine disrupting chemicals (3,7) and ample research connects them to low birth weight, some birth defects and neurodevelopmental conditions (attention deficit disorder and autism), gestational diabetes, obesity, and some cancers (4). Plastics and plasticizers (such as bisphenol-A and phthalates), pesticides, industrial chemicals, fuels, flame retardants and perfluorinated compounds are all classified as endocrine disruptors (3,8). 

These man-made chemicals affect both male and female reproduction and development. They are linked to breast and prostate cancer, thyroid dysfunction, cardiovascular endocrinology, estrogen promotion; androgen antagonism; thyroid dysfunction; steroid metabolism; and alterations in neurotransmitters (serotonin, dopamine and norepeniphrine) (7). 

Yikes! What does that mean for us? Let’s look at toxic exposure during one lifespan.

Pre-conception: A woman’s chemical exposure prior to becoming pregnant may alter gene expression (potentially affecting multiple generations)4, and may affect her offspring’s risk for childhood cancer (3). A 2003 study found that every pregnant woman in America is exposed to at least 43 different chemicals (3). That was 15 years ago…

Prenatal: Chemical exposure alters fetal cellular programming and may affect development of sexual organs, thyroid’s role in brain development (7), and may lead to polycystic ovary syndrome later in life (8). Also during gestation, chemicals such as methyl mercury cross the placenta and amass in the fetus (3).

Infancy: During early rapid growth, toxins in the environment, breast-milk and/or soy formulas may hinder development of the hypothalamus or neuroendocrine arrangement, both of which play a role in reproduction (7).

Adolescence: Males may experience premature growth of pubic hair, small testes and either early or delayed puberty (dependent on fetal exposure) (9); females may experience premature breast development and/or puberty, polycystic ovary syndrome and delayed ovulation (7).

Adulthood: A lengthy list of endocrine and reproductive system related disorders includes interference with menstruation, fertility and menopause, and multiple cancers (3,7).

Lifetime: Low-dose, chronic contact with indoor and outdoor toxins is as detrimental to health as one harsh exposure. Sadly, only policy change will help reduce potential contaminants (7).

Meanwhile, we must reduce our toxic load. Shift as many variables to exposure as possible. Start with food – aim for sustainably raised, whole food products free of preservatives, herbicides and pesticides. Eating organic foods in no or toxin-free packaging significantly lowers measured levels of toxins. Test your water – most is treated chemically, and bottled water leaches endocrine-disrupting chemicals from their plastic containers (3).

What else? Consider consulting with an experienced nutritionist (like me!) to inquire about functional lab tests to measure endocrine function or metal burden, to learn about “clean” eating and environmental habits, and perhaps to embark on an individualized, scientifically supported liver-clearing program that addresses all phases of detoxification.

REFERENCES

1 Allen, J., Montalto, M., Lovejoy, J., & Weber, W. (2011). Detoxification in Naturopathic Medicine: A Survey. Journal of Alternative and Complementary Medicine, 17(12), 1175–1180. http://doi.org/10.1089/acm.2010.0572

2 Duncan, D.E. (n.d.). Chemicals within us. National Geographic. Retrieved from https://www.nationalgeographic.com/science/health-and-human-body/human-body/chemicals-within-us/

3 Exposure to toxic environmental agents: Committee opinion no. 575. (2013). The American College of Obstetricians and Gynecologists: Women’s Health Care Physicians, 122: 931-5.

4 Zlatnik, M.G. (2016). Endocrine-Disrupting Chemicals and Reproductive Health. Journal of Midwifery & Womens Health; 61(4): 442-55. doi: 10.1111/jmwh.12500.

5 Sengupta, P., Banerjee, R., Nath, S., Das, S. & Banerjee, S. (2015). Metals and female reproductive toxicity. Human & Experimental Toxicology; 34(7): 679-97. doi: 10.1177/0960327114559611.

6 Dunn, K. (n.d.). How do hormones work? PBS.org. Retrieved from https://www.pbs.org/wgbh/pages/frontline/shows/nature/etc/hormones.html

7 Diamanti-Kandarakis, E., Bourguignon, J.-P., Giudice, L. C., Hauser, R., Prins, G. S., Soto, A. M., … Gore, A. C. (2009). Endocrine-Disrupting Chemicals: An Endocrine Society Scientific Statement. Endocrine Reviews, 30(4), 293–342. http://doi.org/10.1210/er.2009-0002

8 Rutkowska, A.Z and Diamanti-Kandarakis, E. (2016). Polycystic ovary syndrome and environmental toxins. Fertility and Sterility; 106(4): 948-58. doi: 10.1016/j.fertnstert.2016.08.031.

9 Sengupta, P. & Banerjee, R. (2014). Environmental toxins: alarming impacts of pesticides on male fertility. Human & Experimental Toxicology; 33(10): 1017-39. doi: 10.1177/0960327113515504.