Exposure of the adult population resident in Ireland to dioxins and PCBs from the diet

Irish monitoring data on PCDD/Fs, DL-PCBs and marker PCBs were collated and combined with Irish adult food consumption data to estimate dietary background exposure of adults (18-90 years of age) living in Ireland to dioxins and PCBs. The average upper-bound daily intake of dioxins total WHO TEQ (2005) (PCDD/Fs and DL-PCBs) from food contaminated via the environment was estimated as 0.3 pg kg^-1 bw day^-1 and at the 95th percentile at 1 pg kg^-1 bw day^-1. The average upper-bound daily intake of sum of six marker PCBs from food contaminated via the environment was estimated at 1.6 ng kg^-1 bw day^-1 and at the 95th percentile at 6.8 ng kg^-1 bw day^-1. Dietary background exposure estimates for both dioxins and PCBs indicate that the Irish adult population has exposures below the European average, a finding which is also supported by the relatively lower levels detected in breast milk of Irish mothers compared with breast milk levels reported for other European countries. Exposure levels are below health-based guidance values and/or body burdens associated with the tolerable weekly intake (TWI) (for dioxins) or associated with a no observable adverse effect level (NOAEL) (for PCBs). Given the current toxicological knowledge, based on biomarker data and estimated dietary exposure, the authors consider that general background exposure of the Irish adult population to dioxins and PCBs is not likely to be of human health concern.