This report is one of a series in which the results of the Health Protection Agency (HPA) Environmental Radioactivity Surveillance Programme are presented. It contains the measurement data for the year 2011. Within the main programme, samples of airborne dust and milk are collected routinely from selected locations within the UK, the Channel Islands and the Isle of Man. The activity concentrations of various radionuclides are measured. In general, the radionuclides detected result from nuclear weapons tested in the atmosphere in earlier years and from the nuclear reactor accident at Chernobyl in the Ukraine in 1986, although the programme is able to detect any other sources of significant contamination. In March 2011, the accident at the Fukushima Dai-ichi nuclear power plant in Japan gave rise to very low levels of radioactivity in the environment in the UK. The measurements undertaken by the HPA following the accident are included in this report.
The results from the main programme indicate that concentrations of artificial radionuclides in the general environment remain at the low levels observed in recent years.