Atrazine Uptake, Elimination, and Bioconcentration by Periphyton Communities and Daphnia Magna: Effects of Dissolved Organic Carbon

Abstract

The bioconcentration and toxicokinetics of atrazine in three different periphyton communities and in laboratory reared Daphnia magna were studied in natural and artificial waters with different dissolved organic carbon (DOC) concentrations and qualities. The exposure concentrations were similar to those short-lived peak concentrations found in contaminated waters. Atrazine uptake and elimination were very fast, and the bioconcentration was low both in periphyton and D. magna. The bioconcentration factors in D. magna were approx. 16% of those in periphyton. The uptake and elimination rates were also higher in periphyton than in Daphnia. The periphyton properties affected the bioconcentration of atrazine more than the DOC concentration and water quality. A steady state was reached within a few hours of uptake by the periphyton and within 24 h by D. magna. A residue of atrazine was left in the periphyton and D. magna after an 8-h biphasic depuration with clearly distinct fast and slow phases. In D. magna, atrazine may be eliminated during the normal life span of the organism. These results suggest that DOC has a minor influence on the toxicokinetics of atrazine.

Development of negligible depletion hollow fiber–protected liquid-phase microextraction for sensing freely dissolved triazines

“…This phenomenon also was observed for other polar compounds, such as dinitrophenolic compounds [32], bisphenol A [33], and alkylphenols [17]. Biological exposure experiments indicated that statistically, the bioavailability of ATR was not affected by the DOM [28,29], but enhanced uptake by Daphnia magna was observed in cases with low DOC concentrations [28]. Lorenz et al [34] also reported that DOC increased the toxic effect of the triazine herbicide terbutylazine on zebrafish.…”

“…In fact, the effect of DOM on the availability of triazines remains controversial. Membrane dialysis results indicated that ATR could associate with DOM through interior adsorption sites on the DOM molecule by transitory hydrogen bonding and subsequent physical entrapment [27], suggesting that DOM might reduce the availability of ATR, which disagrees with exposure results reported in the literature [28,29]. Ultrafiltration results [30] demonstrated relatively low binding affinity of humic substances for ATR, and the reported K OC values (partition coefficients for the binding affinities of ATR) to 16 different humic materials varied from 87 to 575 L/kg of carbon.…”

“…Chem. 28,2009 X. Hu et al the normalized C free of the triazines were slightly enhanced with the addition of DOC. For the tested humic acid solutions, statistical analysis with one-way analysis of variance indicated that the normalized C free of each analyte in the DOC-present solutions generally was not significantly different from that in the DOC-free solutions ( p Ͼ 0.05), except for SIM or ATR in higher concentrations of DOC (25 or 50 mg/L).…”

The influence of particles on bioavailability and toxicity of pesticides in surface water

“…Moreover, Akkanen et al () found that DOM properties (i.e., origin and phenolic and carboxylic group content in DOM) had no effect on uptake, elimination, or bioconcentration of atrazine in both periphyton communities and D. magna (Akkanen et al ). In another study, the authors concluded that the log K OC of atrazine is too low for its bioconcentration to be affected by the presence of DOM at concentrations up to 21 mg/L (Nikkilä et al ). Schramm et al () suggested, however, that the low experimentally observed lipophilicity of aquatic DOM (which is >50‐fold less lipophilic than the terrestrial DOM) might be the reason for the lack of effects by DOM on the bioavailability of the triazines cyromazine, simetone, and terbuthylazine.…”

Combined effects of a herbicide (atrazine) and predation on the life history of a pond snail, Physa gyrina

“…Bioconcentration factors indicate that atrazine is accumulated by algae 223) and mayfly nymphs (480), but accumulation by amphibians (not detectable), crustaceans (2.2-4.4), freshwater * To whom correspondence may be addressed (ncarmosi@purdue.edu). snails (4)(5), and fish (0.3-12) typically is low [16,21,22]. Although atrazine does not bioconcentrate in many aquatic organisms (log K ow ϭ 2.68), the pesticide is taken up, and transient concentrations can influence life-history traits by disrupting immune and endocrine processes [1,5,[23][24][25].…”