Emerging Contaminants and Endocrine Disrupting Chemicals
Contaminants of emerging concern ("emerging contaminants") are chemicals and other substances that have no regulatory standard, have been recently discovered in natural streams (often because of improved detection methods), and may damage aquatic life and human health. They are pollutants not currently included in routine monitoring programs and may be candidates for future regulation.
Emerging contaminants include:
Persistent organic pollutants (POPs) such as some flame retardants, insecticides, and other organic chemical contaminants.
Pharmaceuticals and personal care products (PPCPs), include any product used by individuals for personal health or cosmetic reasons or used by agribusiness to enhance growth or health of livestock. PPCPs comprise a diverse collection of thousands of chemical substances, including prescription and over-the-counter therapeutic drugs, veterinary drugs, fragrances, sunscreens, detergents, and cosmetics.
Endocrine-disrupting chemicals (EDCs), including synthetic estrogens and androgens, naturally occurring estrogens, and other chemicals that affect hormonal functions in aquatic organisms.
Nanomaterials, such as carbon nanotubes, or nano-scale particulate titanium dioxide used in sunscreens, cosmetics, paints and coatings.
Recent research has focused on developing analytical methods to measure contaminants down to trace levels, determining their occurrence, characterizing ways contaminants are reaching the environment, determining what happens to these chemicals and where they go in the environment, and identifying the potential ecologic effects from exposure to these contaminants. Of these emerging contaminants, some are capable of disrupting the endocrine system of animals, including fish, wildlife, and humans; these are termed endocrine disrupting chemicals or EDCs. ( More about studies on our rivers.)
What is the endocrine system?
The endocrine system is distributed throughout the body and includes: glands, hormones synthesized and secreted by the glands into the bloodstream, and receptors in the various target organs and tissues which recognize and respond to the hormones. The system regulates a range of biological processes, including control of blood sugar, growth and function of reproductive systems, regulation of metabolism, brain and nervous system development, and development of an organism from conception through adulthood and old age. Disruptions in hormonal balance at critical life stages may have long-lasting effects.
(Source EPA)
Sources of EDCs in the environment include wastewater effluent, combined sewer overflows, stormwater runoff, industrial discharges, landfills, agricultural runoff, and livestock yard runoff. Some chemicals with endocrine disrupting effects are old, tried and true pollutants, like pesticides and heavy metals and many are emerging contaminants.
EDCs include:
- Human & veterinary drugs (e.g. antibiotics, hormones, steroids)
- Plasticizers
- Fire retardants
- Antioxidants
- Disinfectants
- Fumigants
- Fragrances
- Detergents
- Sunscreens
- Insecticides/ repellants
- Nanomaterials
- Heavy metals
The Endocrine Disruption Exchange has an extensive list of chemicals with documented endocrine disrupting effects.
Effects of endocrine disruption in fish include intersex characteristics (e.g. presence of oocytes in male gonads or presence of spermatocytes in female gonads), female-biased sex ratios, reduced sperm abundance, impaired ovarian function.
The Trail of Evidence: there is a growing body of scientific evidence of the effects of both emerging contaminants and EDCs since the masculinization of female fish was observed in pulp-mill affected streams in the 1970s.
What can be done in the short term?:
- Legislation for prescription medication take-back and product stewardship
- Funding for advanced wastewater treatment processes and alternatives
- Continued research on sources and effects of EDCs
- Strong regulatory action to reduce discharge of harmful emerging contaminants to rivers, lakes and groundwater
