According to new research, Parabens, a form of preservative widely used in cosmetic and pharmaceutical products, have begun showing up in the tissues of various marine mammal species, including dolphins, sea otters and polar bears.
The preservative is found in shampoos, commercial moisturisers, shaving gels, personal lubricants, topical/parenteral pharmaceuticals, spray tanning solution, makeup, and toothpaste and is used to prevent bacterial growth and extend products’ shelf-lives.
Parabens have long been to known to be found at low levels inside many humans, with an analysis by the Centers for Disease Control and Prevention finding that most Americans whom they tested had detectable levels of parabens in their urine. The potential effects on humans are so far unclear however they have been linked with exhibiting estrogenic activity in animals.
As various waste products containing these preservatives wash into the sewage system, they can potentially be released into the marine environment. In a recent study, Kurunthachalam Kannan and colleagues set out to investigate whether marine mammals who were being exposed to these preservatives through sewage entering the ocean, were accumulating parabens in their body tissue too.
The researchers analysed 121 tissue samples from eight species of marine mammals from the coastal waters of Florida, California, Washington and Alaska. They detected methyl paraben in many of the samples. A metabolite of methyl paraben called 4-hydroxybenzoic acid (4-HB) was in every sample. The levels ranged from trace amounts of methyl paraben in polar bears to tens of thousands of nanograms of 4-HB per gram of tissue in some dolphins and sea otters. The metabolite also occurs naturally in plants, but the scientists say the positive correlation between methyl paraben and 4-HB in samples suggests they come from synthetic sources. The team of researchers add that further research is needed to determine what potential health risks these substances might pose to marine animals.
- Jingchuan Xue, Nozomi Sasaki, Madhavan Elangovan, Guthrie Diamond, Kurunthachalam Kannan. Elevated Accumulation of Parabens and their Metabolites in Marine Mammals from the United States Coastal Waters. Environmental Science & Technology, 2015; 151002094531007 DOI: 10.1021/acs.est.5b03601