Partitioning of Polybrominated Diphenyl Ethers to Dissolved Organic Matter Isolated from Arctic Surface Waters

Abstract

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardant that is distally transported to the Arctic. Little is known about the fate of PBDEs in Arctic surface waters, especially in the presence of dissolved organic matter (DOM). DOM has been shown to interact with hydrophobic organic contaminants and can alter their mobility, bioavailability, and degradation in the environment. In this study, the partitioning of six PBDE congeners between Arctic DOM (isolated via solid phase extraction) and water was measured using the aqueous solubility enhancement method. Measured dissolved organic carbon (DOC)-water partition coefficient (KDOC) values were nearly an order of magnitude lower than previously reported values for the same PBDE congeners in soil or commercial organic matter, ranging from 10(3.97) to 10(5.16) L kg(-1) of organic carbon. Measured results compared favorably with values calculated using polyparameter linear free energy models for Suwannee River fulvic acid. Log KDOC values increased with increasing PBDE hydrophobicity. Slightly lower than expected values were observed for the highest brominated congeners, which we attribute to steric hindrance. This study is the first to comprehensively measure KDOC values for a range of PBDE congeners with DOM isolated from Arctic surface waters.

The photodegradation of polybrominated diphenyl ethers (PBDEs) in various environmental matrices: Kinetics and mechanisms

“…Strong hydrophobicity and low solubility in water cause PBDEs to show strong partitioning affinity to organic matrices [20]. This is why the majority of studies of the photochemical behavior of PBDEs in liquids have focused on organic solvents such as methanol, acetonitrile and hexane as a proxy media simulating the natural environment.…”

“…PBDEs are identified as endocrine disruptors that can impact liver enzyme reactivity, affect thyroid hormone levels, induce immunotoxicity, hinder neurodevelopment, and cause DNA damage [14][15][16][17]. Because of their prevalence in various environmental matrices and potential toxicity to wildlife and humans, there have been lots of recent investigations into the environmental fate and treatment technologies for PBDEs,, such as biodegradation [18,19], adsorption [20,21], photodegradation [22,23], zero-valent iron dehalogenation [24,25] and advanced oxidation processes [26] .…”

Role of microgel formation in scavenging of chromophoric dissolved organic matter and heavy metals in a river-sea system

“…The impacts of these materials, including colloid or DOC biopolymers, on the ecosystem, could be vast, for example, in their participation in various biogeochemical reactions such as microbial loop, element exchange, light absorption and food webs [1,2]. Some studies also indicated that DOC alters the mobility of pollutants which in turn affects their bioavailability, and acts as a critical regulator for pollutant toxicity [3][4][5]. The capability of these materials comes from some functional groups present within the natural organic matter structure, such as polysaccharides, proteins, lipids, nucleic acids and various functional group types (carboxylate, sulfate, and phosphate) [6][7][8].…”

Characterization of Dissolved Organic Matter in River Water by Conventional Methods and Direct Sample Analysis-Time of Flight-Mass Spectrometry

“…In recent years research work related with DOM has increased considerably, because of its effect of retention or transport of organic and inorganic pollutants in different natural substrates [5,16,17].…”