Tumors and sex changes: part deux

Suspected Morro Bay pollutant looks more prevalent than previously believed



GROWING CONCERN :  Local scientists guessed last spring that tumors found in Morro Bay goby fish were caused by sewage runoff. After doing the research it turns out they’re probably right. - FILE PHOTO COURTESY OF SARAH JOHNSON
  • GROWING CONCERN : Local scientists guessed last spring that tumors found in Morro Bay goby fish were caused by sewage runoff. After doing the research it turns out they’re probably right.
In spring of 2008, scientists from Cal Poly discovered that about 10 percent of goby fish collected in Morro Bay were plagued by bulbous liver tumors. At the time they hypothesized the gobies were being poisoned by sewage runoff and a common chemical found in everything from detergents to spermicides. After some preliminary research, it looks as though their first guess was right and, perhaps, not broad enough in scope.


The chemical in question is called nonylphenol (pronounced “non-il-fe-NALL”). It results from chemical breakdowns, most commonly during sewage treatment processes. In fact, beyond being a suspected goby carcinogen, nonylphenol has been linked elsewhere as causing gender changes in gobies. The European Union all but banned the chemical in most uses and Canada officials labeled it as toxic. In the United States, however, nonylphenol is considered an inert ingredient, which is part of the problem, according to Dan Berman, program director of the Morro Bay National Estuary Program.


“It’s especially worrisome because the stuff is really ubiquitous,” Berman said. “It’s in personal products like shampoo and it’s not listed on the ingredients because technically it’s not an active ingredient.”


In other words, nonylphenol has an easy avenue into the environment. Nonylphenol concentrations found in Morro Bay are just among the few known studied areas in California. The Cal Poly research group, headed by biologists Lars Tomanek and Dean Wendt, also found nonylphenol in Tomales Bay and as far north as Oregon. Tomanek and Wendt stressed that the data is still very preliminary and, while it points to a correlation between nonylphenol and ecological problems, hasn’t proven a causal link.


Out of 60 organic pollutants studied in Morro Bay, nonylphenol is considered to be the main candidate for causing tumors in gobies, Tomanek said. Levels in the water were fairly low, about .5 parts per billion. The average concentration in sediment, however, was about 32 parts per billion. Sediment concentrations were found as high as 87 parts per billion from samples collected near the State Park marina.


“It’s emerging I think in sort of our collective consciousness,” said Karen Worcester of the Regional Water Quality Control Board. “Probably we need to figure out ways to address it.”


There were nonylphenol concentrations of 716 parts per billion found in samples of goby livers, according to the Cal Poly research. The chemical may also cause liver and gonadal tumors in other organisms.


When the tumors were first discovered one of the unanswered questions was whether nonylphenol was accumulating in other species. According to the research, the answer is a definitive yes.


Some Pacific oysters in Morro Bay had nonylphenol concentrations of up to 363 parts per billion found in their digestive tissues. There is no known health risk for human consumption of nonylphenol. Morro Bay Oyster Company owner Neal Maloney stressed that his company complies with all state health laws.


“We wouldn’t give anything to the public which we and the health department didn’t think was safe for humans and something I wouldn’t eat myself,” Maloney said.


Tomanek and Wendt stressed the same point: nonylphenol has not been shown to be a health risk to humans. They said there’s more work to be done and the findings await peer review. Maloney agreed: “We’re stewards of the bay; we want to find pollution as well. But until the science is done I think it’s kind of premature to blow the whistle.”


Furthermore, the chemical is prevalent throughout the state and really, across all U.S. coastlines.


“This stuff is everywhere,” Wendt said. “Not just in Morro Bay; it is not just a Morro Bay issue.”


After the goby tumors were first discovered, Tomanek and others suspected nonylphenol was produced mostly in septic and other sewage processing systems, then leaked into the bay through other water bodies as treated effluent. In Chorro Creek, upstream of the California Men’s Colony wastewater treatment there was no detectible nonylphenol in the sediment. But 100 meters downstream the sediment contained 610 parts per billion.


In the sludge byproducts tested in a septic pump tank that serves 186 Los Osos homes, there was a staggering 5 million parts per billion. Tomanek and Wendt wrote a letter to county officials raising the nonylphenol issue now that the Los Osos sewer project is nearing construction.


“Although it is not a unique problem to Morro Bay, at this point it occurs that it is the major pollutant threatening the marine life in Morro Bay,” they wrote.


The response: “The Los Osos Waste Water Project would not discharge into any stream or Morro Bay. Sludge from the treatment facility will be disposed in appropriate landfills.”


If the chemical truly is causing tumors in gobies and problems in other marine life, the next steps could still be tricky. There are no regulations in the U.S. as there are in other countries, though the Environmental Protection Agency, in response to court challenges from the Environmental Law and Policy Center, the Sierra Club, and other similar groups, has begun the process to review whether nonylphenol should be on a federal watch list of toxic chemicals in water and sediment. The comment period for the federal review ended on Sept. 15.


Meanwhile, there’s no way to ask people not to use products containing the chemical because it’s not required to be listed in the active ingredients. Asked about possible solutions, Berman said, “Rather than asking people to change their personal behavior, we just need to get this stuff out of the system—if it’s as serious as it’s looking like.”


Staff writer Colin Rigley can be reached at



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