Dioxins and Polychlorinated Biphenyls in Human Breast Milk: Pilot Biomonitoring Data from Greater Poland Province

Persistent organic pollutants such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) remain a public health concern due to their persistence, bioaccumulation, and potential health effects. Human breast milk is an important biomonitoring matrix for assessing maternal and infant exposure to lipophilic contaminants. This pilot study aimed to determine concentrations of PCDD/Fs, dioxin-like PCBs (dl-PCBs), and non-dioxin-like PCBs (ndl-PCBs) in breast milk samples collected from five lactating women residing in the Greater Poland Province and to explore potential determinants of exposure. Following participant recruitment, sample collection, and questionnaire-based assessment performed by the authors, breast milk samples were analyzed at the accredited Laboratory of Trace Analysis (Cracow University of Technology, Poland) using isotope dilution gas chromatography coupled with tandem mass spectrometry. Toxic equivalency values (TEQ) were calculated using World Health Organization 2005 toxic equivalency factors (WHO-TEFs). WHO-PCDD/F-TEQ ranged from 0.096 to 0.22 pg/g fresh weight. Median lipid-normalized WHO-PCDD/F-TEQ and total WHO-PCDD/F-PCB-TEQ concentrations were 3.5 and 4.7 pg/g lipid, respectively, remaining below the European Food Safety Authority (EFSA) reference level of 5.9 pg/g lipid; only one sample exceeded this threshold (6.2 pg/g lipid). Lipid-normalized WHO-PCB-TEQ correlated positively with maternal age (ρ = 0.949, p = 0.0389). The observed values were within the lower range reported in recent European studies. The congener patterns suggest a combination of chronic exposure to combustion by-products and long-term bioaccumulation of historical industrial pollutants. Although limited by the small sample size, this exploratory study provides preliminary regional biomonitoring data supporting future environmental exposure research.