Spatial variance of POPs and heavy metals in transformer oil-contaminated soil around Tamil Nadu

Lactational exposure to dioxin-like polychlorinated biphenyl 169 and nondioxin-like polychlorinated biphenyl 155: Effects on rat femur growth, biomechanics and mineral composition

Exposure to polychlorinated biphenyls (PCBs), which are persistent lipophilic environmental pollutants, has a variety of adverse effects on wildlife and human health, including bone mineralization, growth and mechanical strength. The present study evaluated the effects of lactational exposure to nondioxin-like PCB-155 and dioxin-like PCB-169, individually and in combination, on pubertal rat femur development and its biomechanics. After offspring delivery, Wistar rat mothers were divided into four groups, i.e., PCB-169, PCB-155, PCB-155+169 and control, and were administered PCBs intraperitoneally. Data on bone geometry, biomechanics and mineral composition were obtained by analysis of femurs from 42-day-old offspring by microCT scanning, three-point bending test and inductively coupled plasma mass spectrometry. Decreased somatic mass and femur size, i.e., mass, periosteal circumference and cross sectional area, were observed in the PCB-169 and PCB-155 groups. Additionally, lactational exposure to planar PCB-169 resulted in harder and more brittle bones containing higher amounts of minerals. Combined exposure to structurally and functionally different PCBs demonstrated only mild alterations in bone width and mineralization. To conclude, our results demonstrated that alterations, observed on postnatal day 42, were primarily induced by PCB-169, while toxicity from both of the individual congeners may have been reduced in the combined group.

Presence and distributions of POPS in soil, atmospheric deposition, and bioindicator samples in an industrial-agricultural area in Turkey

In this study, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were detected in the soil, lichen pine needle, and total deposition samples in the Meriç-Ergene Basin, which is one of the most important regions in terms of industrial and agricultural activities in Turkey. POP concentrations were measured in 192 samples selected to represent four seasons over a 1-year period across four different regions: an intensive industrial area, an industrial + residential area, an agricultural area, and a background area. Total PAH concentrations are found in the range of 69.6-887.6 ng/g, 74.6-1277.7 ng/g, 113.4-588.9 ng/g, and 0.00-937.8 ng/m²-day; total PCB concentrations are 9.98-62.9 ng/g, 6.8-68.1 ng/g, 11.3-32.7 ng/g, and 0.00-144.4 ng/m²-day; total OCPs concentrations are 5.9-83.2 ng/g, 7.3-85.6 ng/g, 9.9-97.1 ng/g, and 0.00-137.6 ng/m²-day respectively for soil, lichen, pine needles, and bulk samples. The data were evaluated according to pollutant groups and spatial and temporal changes. The highest PAH and PCB values were detected in lichen samples from industrial areas. The highest OCP values were detected for total deposition and soil samples and in the agricultural area. The results showed that two- to three-ring PAHs, hepta-PCBs, and cyclodienes were the most widespread pollutant groups. Statistical analyses were performed to evaluate the accumulation and indication properties of the matrices in the study for 0.05 significance level. The pollutant group in which matrices are most similar is PAHs. Total deposition samples showed the most different pattern in terms of indications, especially for PCBs. For OCP results, the concentration values obtained in soil samples were different from all other matrices. It was determined that the indication properties of the matrices identified as pollutant indicators differ markedly from the pollutant type, and this difference is at the lowest level for PAH pollutants. Graphical abstract ᅟ.