Assessment of the exposure of breast milk to persistent organic pollutants in Latvia

According to the National Implementation Plan on persistent organic pollutants (POP) for the years 2004–2020 the situation on POP was actualised in Latvia. The aim of the study was to assess the contamination of breast milk with polychlorinated biphenyls (PCB), polychlorinated dibenzodioxins, dibenzofurans (PCDD/PCDF) and some pesticides. Breast feeding mothers (together 30) were selected from probably polluted area, and a control group on the basis of WHO criteria for donor selection. The concentration of POP in milk was detected by gas chromatography with HRGC/HRMS, HRGC/ECD and GC/ECD detection after extraction of milk fat and purification. The results of the survey show comparability of both groups in age, weight, habits, occupation as well as age of the children and the weight at birth and at the time of collecting the samples. PCB were not observed in 15.9%, PCDD/PCDF in 6.6% and pesticides in 14% analyses of the target group and in 26.3%, 7% and 8.6% analyses correspondingly of the control group. The concentration of 18 detected PCB, 17 detected PCDD/PCDF and 8 chlorinated pesticides and its metabolites varied in wide range and the differences of mean values within groups were not statistically significant (p>0.05). The concentration of POPs corresponds to lowest levels detected in European countries. The concentration of dioxine-like PCBs and PCDD/PCDF according to toxicity equivalents does not exceed the WHO accepted level of 15 TEQ pg/g milk fat.