Genetic mutations found in birds living in an industrial harbor in Canada are raising new questions about possible long-term consequences of polluted environments.
Researchers discovered that herring gulls in Ontario’s smokestack-ringed Hamilton Harbour were more than twice as likely to have irregularities in their genetic coding as birds living in more rural areas. The mutations turned up within the birds’ “junk” DNA, strands of genetic material more prone to mutation but unlikely to seriously affect health.
Behavioral ecologist James Quinn of Ontario’s McMaster University suspects the mutations were caused by polycyclic aromatic compounds, byproducts of fossil fuel combustion common in industrial areas. In the Proceedings of the National Academy of Sciences, Quinn describes mutations in parent birds’ egg and sperm cells that were passed on to nestlings.
While acknowledging that there may be other explanations for the scrambled DNA, Quinn notes similarities between the mutations found in the herring gulls and those of people exposed to radiation in the 1986 Chernobyl nuclear accident.
“We’re looking at the same types of changes in mutation rates,” Quinn said. “In Chernobyl, you expected to see changes. Now we’re comparing that to a harbor where people are living peacefully, not thinking about the pollutants that are being pumped into the atmosphere.”