USC Dana and David Dornsife College of Letters, Arts & Sciences

New research categorizes pharmaceuticals as emerging contaminants because of the harmful effects being seen in marine ecosystems. Emerging contaminants such as pharmaceuticals, industrial byproducts, and pesticides are entering marine ecosystems and affecting them in a detrimental way. As defined by the EPA, an emerging contaminant is “a chemical or material characterized by a perceived, potential, or real threat to human health or the environment or by a lack of published health standards.. Though their exact effects on marine ecosystems are not known because of minimal monitoring and lack of extensive research, some studies have shown to be toxic to aquatic life. These contaminants generally from agriculture, industry, and households can interfere with hormone systems affecting reproduction and growth in marine organisms. We should be concerned about the presence of these emerging contaminants because it is unknown where exactly they come from, what their full effects are, or the result of their interactions.

The Southern California Coastal Water Research Projecthas done a lot of research including studies of contaminants in wastewater. For example, these contaminants are known disrupters to the endocrine system interfering with reproductive hormones such as estrogen and testosterone in male flatfish. The presence of estrogen in these waters can be due to the cycling of birth control and through urination, can enter water, and thus affect the reproductive systems of aquatic organisms. One study measured the potential effect of emerging contaminants on the Southern California coast by the collection of hornyhead turbot fish. This fish in particular was chosen because it lives in the depth at which wastewater is released. Samples from the fish from various locations were taken and tested for specific emerging contaminants. “These findings indicate that aquatic life is exposed to a wide variety of emerging contaminants, even after 100- to 1000-fold dilutions of wastewater effluent in the ocean.”

The lack of knowledge regarding emerging contaminants is due to the focusing of specified contaminants recognized decades ago. The list of contaminants is growing continuously, so the use of old data could be disastrous. The difficulties associated with assessment of the contaminants have to do with ”the distribution and bioeffects of these contaminants comes from a lack of detailed understanding of chemical and toxicological interactions in a very complex environment.” There are many unknowns when it comes to emerging contaminants, but NOAA suggests that these difficulties should be approached by infrastructure and new research initiatives.