The objective of this study is to comprehensively characterize persistent organic pollutants (POPs) in seawater at Kaohsiung Harbor, focusing on their concentrations, partitioning behaviors, and profiles in both particle and liquid phases. We analyzed 100 L seawater for each sample, finding total dioxin-like toxicity (PCDD/Fs + PCBs + PBDD/Fs) ranging from 0.00936 to 0.167 pg WHO-TEQ/L, with PCDD/Fs accounting for 68 % of total toxicity. POPs predominantly appeared in the particle phase, observed in over 80 % of samples, except for PCBs. The observed correlations between particulate matter (PM) and chlorinated POPs at sites receiving river effluents suggest shared pollution sources. The liquid partition of PCDD/Fs, PCBs, and PBDEs in the seawater shows an inverse relationship with log Kow and a direct proportionality with solubility, particularly above 0.1 μg/L. Furthermore, PBDEs in seawater can transform into PBDD/Fs upon UV light exposure, highlighting another potential pathway for the persistence and spread of these harmful contaminants in the environment. These findings emphasize the need for field-based investigations to assess PBDF formation in aquatic environments and underscore the importance of stronger mitigation strategies, including better wastewater treatment and stricter discharge regulations to reduce POPs in marine ecosystems.
An average 50 ml breast milk samples were collected from 21 lactating primiparous mothers (range 25 to 45 years, mean 33 years), 4-8 weeks after delivery in Penang Island, Malaysia. The geometric mean concentration of the most toxic congeners, 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) was 0.14 pg WHO2005-TEQ g-1 zlipid. The most abundant congeners of PCDD/Fs were octachlorodibenzo-p-dioxin (OCDD) (5.9-75.4%), followed by 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (1,2,3,4,6,7,8-HpCDD) (1.1-30.7%). The geometric mean level of total dioxins and dl-PCBs was 2.2 pg WHO2005-TEQ g-1 lipid, significantly lower than those in developed countries or highly contaminated areas. The total dioxins and dl-PCBs in pg WHO2005-TEQ levels in breast milk were significantly correlated with years of residence at potential contaminated site. The average daily intake of 11.8 pg WHO2005-TEQ kg-1 body weight was estimated for a breastfed infant at 6 months of age. This demonstrates the exposure risk to infants, especially from Penang region, to these pollutants from human milk intake are potentially high during the lactation period.