The results are the findings of a DCU report
Scientists at Dublin City University, say the River Liffey in Dublin is a major carrier of pollutants into seawater.
A new study shows untreated sewage disposal in the past has led to higher than recommended concentrations of chemicals in water at Dublin Bay.
Samples were collected from 30 locations in Dublin Bay in June 2010.
Dr. Brian Kelleher from the School of Chemical Sciences in DCU, says the study's findings shouldn't be cause for panic.
According to the research findings announced on the DCU website, the main focus of the study published in the Marine Pollution Bulletin was to determine the distribution and possible sources of Polycyclic Aromatic Hydrocarbons (PAHs) and faecal sterols in Dublin Bay, and whether these man-made pollutants have an impact on microbiological communities on the sea-bed.