Endocrine disrupting chemicals: Impact on human health, wildlife and the environment

Abstract

Endocrine disrupting chemicals are a group of pollutants that can affect the endocrine system and lead to diseases and dysfunctions across the lifespan of organisms. They are omnipresent. They are in the air we breathe, in the food we eat and in the water we drink. They can be found in our everyday lives through personal care products, household cleaning products, furniture and in children's toys. Every year, hundreds of new chemicals are produced and released onto the market without being tested, and they reach our bodies through everyday products. Permanent exposure to those chemicals may intensify or even become the main cause for the development of diseases such as type 2 diabetes, obesity, cardiovascular diseases and certain types of cancer. In recent years, legislation and regulations have been implemented, which aim to control the release of potentially adverse endocrine disrupting chemicals, often invoking the precautionary principle. The objective of this review is to provide an overview of research on environmental aspects of endocrine disrupting chemicals and their effects on human health, based on evidence from animal and human studies. Emphasis is given to three ubiquitous and persistent groups of chemicals, polychlorinated biphenyls, polybrominated diphenyl ethers and organochlorine pesticides, and on two non-persistent, but ubiquitous, bisphenol A and phthalates. Some selected historical cases are also presented and successful cases of regulation and legislation described. These led to a decrease in exposure and consequent minimization of the effects of these compounds. Recommendations from experts on this field, World Health Organization, scientific reports and from the Endocrine Society are included.

Keywords: Endocrine disruption; children; environment; human health; policy; precautionary principle.

Figure 1.

Production of chemicals considered hazardous to health in European Union 28 countries (EU-28), between 2004 and 2016 (million tons). Consumption does not differ significantly from production. However, consumption is generally higher than production, due to importation. Source: Eurostat.

Figure 2.

Trends in cancer incidence, in the selected countries, by year of diagnosis. Data on trends in incidence for breast, prostate and all cancers excluding non-melanoma skin, for the selected countries, were extracted from CI5plus-Cancer Incidence in Five Continents Time Trends (http://ci5.iarc.fr/CI5plus/Default.aspx).

Figure 3.

Worldwide trends in the number of adults with diabetes by region (a) and decomposed into the contributions of population growth and ageing, rise in prevalence and interaction between the two (b). Source: DOI: https://doi.org/10.1016/S0140-6736(16)00618-8 and Creative Commons Attribution Licence (CC BY).

Figure 4.

Representation of endocrine disruption by EDCs. ER: oestrogen receptor; ERE: oestrogen response element; CoA: coactivators; P: phosphorylation; TF: transcriptional factor.

Figure 5.

Molecular structures of common endocrine disrupters.

Figure 6.

Timeline of lead poisoning prevention policies and blood lead levels in children aged 1–5 years, by year – National Health and Nutrition Examination Survey, United States, 1971–2008.^– Available at https://phil.cdc.gov. Accessed 19 November 2018. The symbol ‘*’ denotes National estimates for GM BLLs and prevalence of BLLs ⩾10 µg/dL, by NHANES survey period and sample size of children aged 1–5 years: 1976–1980: N = 2372; 1988–1991: N = 2232; 1991–1994: N = 2392; 1999–2000: N = 723; 2001–2002: N = 898; 2003–2004: N = 911; 2005–2006: N = 968; 2007–2008: N = 817. The symbol ‘†’ denotes NHANES survey period.