Perfluorooctanoic Acid (PFOA) Transport in Soil and Absorption and Distribution in Alfalfa (Medicago sativa)

Perfluorooctanoic acid (PFOA), used as a surfactant in consumer and industrial products, is frequently found in biosolids from wastewater treatment plants. When present in biosolids applied to croplands, PFOA has potential to contaminate feed and fodder used by livestock, but the extent of PFOA transfer from soil to plants is not well characterized. A single dose of [ 14 C]-PFOA was applied to unplanted soil or soil containing growing alfalfa. PFOA transport through unplanted soil and uptake by alfalfa was monitored over a 10-week study period. Radiocarbon was initially measured in roots, stems, and leaves 7 days after PFOA application to soil. PFOA accumulation was greatest in leaves during the 10-week sampling. By week 10, PFOA migration through unplanted soil had reached a depth of 22.8 ± 2.5 cm. In contrast, PFOA migrated to 7.5 ± 2.5 cm in soil containing alfalfa plants. The greatest predictor of PFOA concentration in alfalfa leaves was PFOA concentration in the top 5 cm of soil; PFOA concentrations at lower depths were not correlated with alfalfa PFOA levels. PFOA transport through soil may be slowed by the presence of forage, however PFOA accumulation in edible portions of forage plants may increase food animal exposure to PFOA residues.

Presence and biodistribution of perfluorooctanoic acid (PFOA) in Paracentrotus lividus highlight its potential application for environmental biomonitoring

The first determination of presence and biodistribution of PFOA in ninety specimens of sea urchin Paracentrotus lividus from two differently contaminated sites along Palermo’s coastline (Sicily) is reported. Analyses were performed on the sea urchins’ coelomic fluids, coelomocytes, gonads or mixed organs, as well as on seawater and Posidonia oceanica leaves samples from the collection sites. PFOA concentration ranged between 1 and 13 ng/L in seawater and between 0 and 794 ng/g in P. oceanica. The analyses carried out on individuals of P. lividus from the least polluted site (A) showed PFOA median values equal to 0 in all the matrices (coelomic fluid, coelomocytes and gonads). Conversely, individuals collected from the most polluted site (B) showed median PFOA concentrations of 21 ng/g in coelomic fluid, 153 ng/g in coelomocytes, and 195 ng/g in gonads. Calculated bioconcentration factors of log10BCF > 3.7 confirmed the very bioaccumulative nature of PFOA. Significant correlations were found between the PFOA concentration of the coelomic fluid versus the total PFOA concentration of the entire sea urchin. PERMANOVA (p = 0.001) end Welch's t-test (p < 0.001) analyses showed a difference between specimens collected from the two sites highlighting the potential application of P. lividus as sentinel species for PFOA biomonitoring.

Contamination Of Perfluorinated Compounds In Sediment of The Cau River, Vietnam

Perfluorooctane sulfonate (PFOS) and Perfluorooctanoic acid (PFOA) are recognized as emerging environmental pollutants because of their high persistence in various environmental matrices and toxic effects on humans and animals. In Vietnam, PFOA and PFOS have been detected in surface water and sediment in recent studies. The objectives of this study were to evaluate the occurrence of PFOS and PFOA in the sediment of the Cau river, Thai Nguyen city to determine the partition coefficient between water and sediment, and to elucidate the environmental factors affecting the sorption of PFOS and PFOA to sediment. The concentration of PFOS and PFOA in surface sediment ranged from 1.19 ng/g to 4.73 ng/g and 0.17 ng/g to 1.78 ng/g, respectively, with the highest concentrations, are recorded in the areas that receiving wastewater from domestic and industrial activities. Depending on the depth, the total concentrations of PFOS and PFOA ranged from 8.41 to 19.25 ng/g and tended to decrease with increasing sediment depth. The concentrations in the surface sediments are lower than the second layer, indicating a downward trend in the use and consumption of these compounds in recent years. The water-sediment distribution coefficient (Kd) is relatively different for PFOS and PFOA, with log Kd values ranged from 1.31–1.86 and 0.08–1.31 for PFOS and PFOA, respectively. This study also confirms that the total organic carbon content is the physiochemical property that significantly affected the adsorption to sediments of PFOS and PFOA. No apparent relation was found between PFOS, PFOA concentration in sediment and clay content nor sediment particle size.

The Concentration Levels of Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoic Acid (PFOA) in Qiantang River Waters of China

To characterize the concentration levels of PFOS and PFOA in the Qiantang River waters of China, 12 water samples were collected in May 2013 and analyzed. The concentrations of PFOS and PFOA were from n.d to 0.798 ng/L and from 65.9 to 102.4 ng/L, respectively. PFOS has been observed at a low concentration in these samples, while PFOA was detected in 100% of the samples with higher PFOA concentrations. PFOA concentrations were far higher than those of PFOS in all the samples, which subjected to be influenced by the inflows of the chemicals from a lot of the textile dyeing industry along the south bank of the river. Although the PFOS and PFOA concentration in Qiantang River water samples did not exceeded this provisional health advisory level (limit) established by the United States Environmental Protection Agency for PFOS and PFOA in drinking waters of 200 ng/L and 400 ng/L respectively, continued exposure to even relatively low PFOS and PFOA concentrations in drinking water may increase the risk of health effects.

Perfluorinated compounds (PFCs) in Yodo River system, Japan

There is increasing concern about occurrences of perfluorinated compounds (PFCs) in the environment due to their persistent, bioaccumulation, and potentially toxic effects. We investigated contamination of 11 PFCs (C4-C12) in the Yodo River system, which is a major source of drinking water for more than 11 million people of Kansai region in Japan. PFCs were detected in higher concentration even exceeding more than 1000 ng/L in some cases. Composition profile of total PFCs concentration showed that PFOS, PFHxA, PFOA, and PFNA were occurring dominantly in the river system. PFOS and PFOA concentration were nearly proportional to a previous study in the same river system, indicating continuous sink of the compounds into the river system. Although discharge of PFCs from wastewater effluents at upstream could be one of the major point sources, concentration did not exceed 29.4 ng/L at the downstream of main Yodo River, possibly, due to dilution effects. Total mass load of PFCs in mainstream of Yodo River was estimated 451.7 g/d based on observed river discharge and PFCs concentration. Results showed that Yodo River system could have a unique upstream-downstream linkage of PFCs contamination and the river could be a continuous pathway of PFCs exposure to the people of Kansai region.