Study finds nanoparticles could contaminate marine life
Too tiny to see or touch, manmade nanoparticles are increasingly becoming a byproduct of industry and chemical and pharmaceutical technology.
But once these super small materials enter the water supply, do they reach coastal areas and enter salt marshes and tidal zones, where shellfish and finfish grow?
Researchers at the University of South Carolina’s Nanocenter, working with scientists at the National Oceanic and Atmospheric Administration in Charleston, examined whether gold nanorods could readily pass from water to the marine food web.
Their findings, published in this week’s edition of Nature Nanotechnology, suggest that nanoparticles move easily into the marine food web and are absorbed in marsh grasses, trapped in biofilms and consumed by filter feeders, such as clams.
“This is the first study to report on the fate of gold nanoparticles in a complex ecosystem containing sediments, biofilms, grasses, microscopic organisms, filter feeders and omnivores,” said environmental chemist Dr. John L. Ferry of the University of South Carolina.
The gold nanorods – rod-shaped nanomaterials that have applications for medicine and even adding color to stained glass -- were used for this study because of their ability to be traced, he said.
For the study, scientists at the Coastal Center for Environmental Health and Biomolecular Research (CCEHBR), a NOAA National Center for Coastal Ocean Science, created three estuarine mesocosms, which are experimental enclosures replicating a coastal estuarine ecosystem. NOAA scientists constructed a tidal marsh creek, containing natural, unfiltered water from Wadmalaw Island; planted Spartina grass in sediments; and added clams, mud snails and grass shrimp. The gold nanorods were synthesized by researchers at the University of South Carolina and introduced into the ecosystems. At the end of the experiment, the university team developed the techniques necessary to measure the transport of the nanoparticles and found that clams and biofilms accumulated the most.