Organohalogens: A persisting burden in Slovenia?

Persistent organic pollutants (POPs) represent a concern for the environment and human health due to their persistence and toxicity. Exposure in Slovenia is geographically differentiated because the country, as part of former Yugoslavia, has a history of industry and regional contamination and is - at the same time - known for its clean nature. The PCB pollution of the Krupa River drew the public's attention to the chemical burden of Slovenians, and the demand for studies has been rising since. We assessed the exposure of men (n = 548) and primiparous women (n = 536) to POPs in 12 regions of Slovenia as well as exposure pathways via questionnaires. Most PCDD/Fs, PCBs, and PBDEs could be determined in pooled samples of maternal milk at low concentrations (1.57 pg/gTEQ, 1.47 pg/gTEQ, and 1076 pg/g fat, respectively), but a much lower number of compounds could be measured above the LOQ in pooled men's plasma samples (PCDD/Fs 0.08 pg/gTEQ, PCBs 0.007 pg/gTEQ, ΣPBDE 920 pg/g), and only HCB, p,p'-DDE, ΣDDT, and the non-dioxin-like PCB congeners 138, 153, and 180 could be determined in individual samples of milk (concentration range 5-60 ng/g fat). In individual samples of men's serum, only p,p'-DDE and ΣPCB were detected at concentrations of 0.25 ng/g and 0.3 ng/g, respectively. Nonetheless, we were able to differentiate between polluted and unpolluted areas on a national level, with higher exposure levels in the PCB polluted region of Bela Krajina, the industrial region Zasavje, and the capital, Ljubljana. Despite low concentrations, determinants of exposure, such as age, proximity to roads, old building materials, private water supplies, and consumption of alcohol, fish, meat, and eggs that have previously been observed only at higher levels could still be identified. Furthermore, levels of PCBs and PBDEs were highly correlated suggesting common exposure sources and pathways, whereas PCDD/Fs were correlated to a lesser extent. The calculated ratio between DDT and DDE in maternal milk samples was decreasing with the year of sampling, suggesting no ongoing exposure to DDT. The study findings suggest low exposure of men and lactating women to legacy pollutants in Slovenia, which gave rise to the hypothesis that Slovenia's geographical location might provide shelter from the long-range transport of POPs via Westerly winds. This hypothesis remains to be confirmed within future studies.

Simultaneous Method for Selected PBDEs and HBCDDs in Foodstuffs Using Gas Chromatography-Tandem Mass Spectrometry and Liquid Chromatography-Tandem Mass Spectrometry.

Flame retardants are added to consumer products to retard the ignition of combustible materials. Technical mixtures of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDD) were massively used for several decades. They are bioaccumulative, persistent, and have adverse effects on organisms. Recognised as persistent organic pollutants, they are banned almost worldwide. Food is the principal source of human exposure. Yet, no maximum residue limits for food have been established in the EU. Nevertheless, monitoring of specific congeners is recommended. Simultaneous analysis of HBCDDs and PBDEs is rarely encountered, especially including BDE-209, as this thermally unstable congener is particularly challenging for analysis. We have developed a method for the simultaneous determination of all relevant PBDEs and HBCDDs recommended for monitoring by the EU. In the method, single sample preparation is used for different types of foodstuffs, applying ultrasound-assisted extraction, clean-up by gel permeation, and adsorption chromatography. Analyses were performed on the same extract, first by GC-MS/MS(EI) method for PBDEs and followed by LC-MS/MS(ESI) method for HBCDDs. The analytical method was validated on a blank sample of milk formula at 2-3 fortification levels, including recommended LOQ level of 0.01 µg/kg wet weight. Satisfactory accuracy with recoveries 85-119%, intra-day precision (1.5-11.3%), and inter-day precision (4.3-18.4%) was obtained. The method ensures LOQs that are compliant with the EU recommendations for all PBDEs and HBCDDs, including BDE-209. Method applicability was further confirmed on proficiency testing samples of baby food, fish, and citrus.