Predicting Bioavailability and Accumulation of Organochlorine Pesticides by Japanese Medaka in the Presence of Humic Acid and Natural Organic Matter Using Passive Sampling Membranes

Abstract

Adsorption to dissolved organic matter (DOM) may significantly decrease the freely dissolved concentration of many hydrophobic organic compounds and, hence, result in reduced bioavailability to aquatic organisms. Here, the suitability of using triolein-embedded cellulose acetate membrane (TECAM) as a biomimetic surrogate to assess the bioavailability of organochlorine pesticides (OCPs) in water in the presence of DOM was explored. The accumulation of OCPs was measured in TECAM and pelagic Japanese medaka (Oryzias latipes) in the laboratory after 12 h exposure to water containing different levels of Aldrich humic acid. Further, OCP uptake by TECAM and medaka in real aqueous environments was evaluated after 30 d exposures in two sites. Laboratory results showed that OCP uptake by medaka consistently decreased with increasing levels of humic acid in the range of 0-15 mg C/L in sample solutions. This tendency was closely mimicked by OCP accumulation in TECAM under the same conditions. Field results showed that TECAM accumulated similar OCP patterns as medaka (r 2 ) 0.92 for site 1 and r 2 )0.94 for site 2), although comparison of the in-field eight OCP concentrations in TECAM to those in medaka yielded approximately a factor of 3 (on a wet weight basis). These results suggest that the TECAM method can be used as a simple and useful tool to predict the bioavailability and bioaccumulation potential of poorly biotransformed organic compounds in pelagic fish in aqueous environment.

Seasonal variation and partitioning of endocrine disrupting chemicals in waters and sediments of the Pearl River system, South China

“…For example, due to heterogeneity of the sedimentary organic matter, specific binding mechanisms other than nonspecific hydrophobic interaction are present between EDCs and SOC, including hydrogen bonding and p-p electron donoreacceptor interaction, which may interfere with EDCs accessing to the receptor binding sites of organisms (Yamamoto et al, 2003;Holbrook et al, 2004). The bioaccessibility reduction of EDCs associated with organic matter is probably due to the formation of aggregates too large or too polar to cross biological membranes (Ke et al, 2007). In addition, as a portion of EDCs sequestered in the aged organic matrix of the sediment are not mobile and hard to be desorbed, this resistant fractions are not bioavailable.…”

Comparison of different triolein-based composite semipermeable membranes for passive sampling of organochlorine pesticides

“…Passive sampling theory has been described in previous studies [21]. Briefly, if the amount of a chemical extracted by a passive sampler during a measurement is very small compared to the total amount in solution, the uptake of the chemical by the passive sampler can be simply described by a first-order, one-compartment model:…”

“…Batch experiments were carried out using the previously described negligible depletion sampling method [21]. Briefly, 1 L of each solution was transferred to 1-L conical flasks and spiked with the six test OCPs to give a nominal concentration of 500 ng/L for each analyte.…”

Development of aquatic life criteria in China: viewpoint on the challenge

“…In addition, in a single-species toxicity test, the direct effect of a chemical on a one species is usually evaluated under controlled laboratory conditions that do not necessarily mimic environmental conditions. For example, physiochemical properties like the dissolved organic carbon concentration and temperature have been shown to considerably alter the magnitude of direct effects of chemicals (Ke et al 2007). Multiple species toxicity tests, often termed microcosm or microcosm experiments, have features that promote their use as a realistic way of assessing chemical-induced stress and enable observation of the indirect effects of chemicals caused by interactions among species and physicochemical factors (Giesy and Odum 1980).…”