That morning trip to the bathroom - to brush your teeth, wash your hair, and put on perfume or cologne - may not be as benign as you think.
Every day, those chemicals wash down the drain. While they are not themselves poisonous, they may affect biological processes in unexpected ways. Now, Stanford University biologists have the mussels to prove it.
Welcome to the new science of ecotoxicology in which scientists try to understand how the synthetic chemicals we're pouring into our environment affect the way earthly life goes about its business.
Recent research about musk fragrances and mussels illustrates this point. When gills from live mussels were exposed to water with low concentrations of six commercial musks, they were not poisoned, point out postdoctoral fellow Till Luckenbach and Prof. David Epel of Stanford. That was expected.
But after two hours, the researchers washed the gills and put them in musk-free water that also contained a red dye. Cells in the gill tissue took up the dye. That was not expected.
Those cells have a mechanism to detect a foreign substance, such as the dye, and keep it out. That worked for cells not exposed to the musk in the first place. Cells that had been exposed lost this natural defense.
That finding has a disturbing global implication, notes the California Sea Grant program, which provided part of the funding for the study. Cells in many animal species, including humans, use the same protective mechanism to ward off foreign substances.