Artificial fragrances in perfumes, soaps, shampoos, cosmetics, and air fresheners — widely regarded as nontoxic — are not necessarily safe for the marine environment, a study funded in part by California Sea Grant shows. In a series of experiments with California mussels, scientists discovered that synthetic musks, while not directly harmful to an organism, increase its sensitivity to toxic agents in the environment. The finding raises concerns that some common household compounds may pose unanticipated risks to the environment and human health. The results were published recently in Environmental Health Perspectives, a journal of the National Institute of Environmental Health Sciences.
The research, led by David Epel, biology professor at Stanford University, showed that synthetic musks compromise a cellular defense mechanism that normally prevents toxins from entering cells. Because synthetic musks are not degraded by sewage treatment and are common in personal health care products, they continuously enter waterways via sewage discharges and runoff. They also accumulate in the tissues of fish and invertebrates as well as in human adipose tissue, blood plasma, and breast milk.
Epel’s team placed gills removed from live mussels in water containing low concentrations of six commercial synthetic musks. Then, after two hours of exposure, they washed the gills and placed them in musk-free water with a red fluorescent dye. Under normal conditions, efflux transporters in the gill tissue would recognize the dye as a foreign compound and remove it, but instead the dye accumulated in cells, an indication that the transport mechanism was impaired. In control groups unexposed to musks, the dye accumulated at much lower rates. In the study groups, cell functioning continued to be impaired 24 to 48 hours after exposure ended, which the scientists called “troubling” since it implies that brief events such as sewage or chemical spills could have lasting environmental effects. Human cells use the same efflux transporter mechanism as mussels, Epel explained, suggesting that the findings have implications for human health, as well.
David Epel, Professor of Biological Sciences
Phone: (831) 655-6226
E-mail: [email protected]
Marsha Gear, Communications Director
California Sea Grant
Phone: (858) 534-0581
E-mail [email protected].
From Sea Grant