Effects of sedimentary sootlike materials on bioaccumulation and sorption of polychlorinated biphenyls

Abstract

Bioaccumulation of hydrophobic organic chemicals from sediments containing soot or sootlike materials has been hypothesized to be limited by strong sorption of the chemicals to the soot matrixes. To test this hypothesis, we quantified bioaccumulation of 11 polychlorinated biphenyls (PCBs) into the aquatic oligochaete Limnodrilus sp. exposed to spiked sediment with and without the sootlike materials coal and charcoal. In addition, sorption experiments with sediment containing varying amounts of coal or charcoal were performed to elucidate the accumulation mechanism. Results showed that coal and charcoal (at realistic levels of 1.5% on a dry-wt basis) reduced PCB accumulation in worms 1.2 to 8.5 times when expressed on a mass basis. Moreover, whereas bioaccumulation from pure sediment increased with molecular planarity of the PCBs (toxic potency), it decreased in case of sediments containing coal and charcoal. In contrast to this advantageous effect, it was hypothesized that coal and charcoal had an adverse influence on the habitat quality of oligochaetes: Organisms inhabiting sediment containing coal or charcoal had significantly reduced lipid contents as compared to organisms from pure sediment. Because of these reduced lipid contents, lipid-normalized PCB concentrations in worms and biota-to-sediment accumulation factors (BSAFs) for most PCBs were higher in sediments containing the sootlike materials as compared to those for reference sediment. Also, measured BSAFs for coal- and charcoal-containing sediments appeared to be much higher than estimated on the basis of equilibrium partitioning theory. Sorption experiments revealed that this was caused by much weaker sorption to the sediment-coal/charcoal mixture than calculated assuming linear additivity of sorption capacities of the distinct phases. It was hypothesized that this weaker sorption resulted from competition between PCBs and dissolved organic carbon molecules for sorption sites on coal/charcoal. This points to a sorption process that is much more complicated than generally assumed.

Characterization of Biochar Derived from Pineapple Peel Waste and Its Application for Sorption of Oxytetracycline from Aqueous Solution

“…In addition, when added to soils, biochar could increase soil nutrients and crop productivity, and improve the soil's physical and chemical properties, such as water retention and nutrient holding capacity (Glaser et al 2009;Laird et al 2010;Paz-Ferreiro et al 2012). Biochar is an excellent sorbent due to its large specific surface area, abundant microporous structure, high hydrophobicity, and aromaticity (Jonker et al 2004). Biochar could effectively remove various pollutants, such as heavy metals, polycyclic aromatic hydrocarbons (PAHs), steroid hormones, pesticides, and antibiotics (James et al 2005;Sarmah et al 2010;Deng et al 2014;Mohan et al 2014;Feng et al 2015).…”

Influence of black carbon and chemical planarity on bioavailability of sediment‐associated contaminants

“…Conversely, the size of nonplanar compounds may exceed the average geosorbent pore size and impair electronic interactions between the compound and the geosorbent surface. Therefore, the steric hindrance caused by bulky atoms, like chlorine in highly chlorinated PCBs, reduced sorption of nonplanar compounds to the geosorbent [1,10,11]. However, BC may strongly sorb some nonplanar compounds, for example, the pesticide diuron.…”

Effects of humic acid and lipid on the sorption of phenanthrene on char

“…It has been observed that sorption ability of BC in the field in the presence of organic matter is not as strong as "intrinsic" BC (Cornelissen and Gustafsson, 2004;Jonker et al, 2004). One of the possible mechanisms is the sorption of natural organic matter (NOM) on BC, leading to the sorption site competition and pore blockage.…”