Events, Research

Down the Drain: Emerging Contaminants in the Marine Environment


URI Lecture Series, Part Three
Metcalf Institute for Marine & Environmental Reporting

Dr. Edward Furlong of the United States Geological Survey lectured a full audience at the Metcalf Institute at the University of Rhode Island Bay Campus in Narragansett on Wednesday, June 6. His presentation, “Down the Drain: Emerging Contaminants in the Marine Environment”, informed those present about EC’s, or Emerging Contaminants, in the environment.

Emerging contaminants include detergents, plastics, and notably pharmaceuticals. The very name EC indicates how they are only recently being studied and talked about amongst scientists as does an exponential increase in the amount of journal publications on subject beginning in 1998. EC’s enter the environment through runoff, human waste, and garbage disposal and unknowingly can be absorbed by animals. Pharmaceuticals consumed by humans, cattle, and pigs also easily find their way into waterways. Among the most recent contaminants to gain prevalence are antivirals, animal growth hormones, antidepressants, cytotoxic drugs (Arthritic medicines), and benzotriazole (a versatile drug precursor and corrosion resistant compound).


The environment, both land and waterways, are laden with EC’s in the realm of parts per million. Even in such small quantities, these invasive chemicals have a way of instigating slight environmental change and behavior in animals. The highest concentrations appear where sewage runoff enters streams and rivers where the compounds can be concentrated. Other concentrated sources include the many antibiotics, pesticides, and growth hormones that are used in the cultivation of crops and the raising of domesticated animals. The contaminants seep in the ground and enter groundwater or are introduced to waterways and over time EC’s become diluted and eventually breakdown. For example, anti-depressants, the second most prescribed drug in America (11% of US pop.), are present in most fishes’ brains and tissue and causes them to be slow and lethargic in the water. This makes it more difficult for them to escape predators.

A bulk of the Emerging Contaminants research performed by the United States Geological Survey was done at various waste and water treatment plants throughout the US.

Most of this research was done in regards to freshwater and groundwater as it is more confined and humans use it or drink it every day. Sea water is less confined and more difficult to sample.

Narragansett Bay is fed by several rivers but Rhode Islanders don’t purify the salt water so we are affected by indirect exposure while swimming and eating the fish that live there. A very interesting notion to consider is the exorbitant use of antibacterial soap and hand sanitizers in recent years. The microbes that survive this cleansing multiply and are also immune to it. This is a kind of forced natural selection of bacteria. It is possible that there will be a decline in effectiveness over the years because of this.

In closing, Furlong admitted that more research needed to be done as there can never be enough data collected on a subject. The more data there is, the more accurate an interpretation can be. Aside from the USGS, the National Oceanographic and Atmospheric Administration (NOAA) is also in the process of researching the risks of EC’s for humans with sampling operations in California, South Carolina, and Puerto Rico. The last words that he left the audience with were not to panic and to simply be aware of our environmental impact.