Transfer modelling and toxicity evaluation of the effluent from an installation of cleansing and uranium recovery using a battery of bioassays

Abstract

On July 7, 2008, a leak of effluent from an Installation of Cleansing and Uranium Recovery (Tricastin, France) led to the spillage of uranium in a stream. The acute toxicity of the effluent was evaluated, and compared to the toxicity of uranium nitrate in bioassays using several organisms: Chlamydomonas reinhardtii, Daphnia magna, Chironomus riparius and Danio rerio. A sediment bioassay was also performed on C. riparius using water and sediment sampled along the river. Results showed that effluent EC(50) 72 h was 0.65 mg U/l for algae and LC(50) 48 h was 1.67 mg U/l for daphnia, while values obtained for uranium nitrate were higher. The LC(50) 96 h of effluent to C. riparius was 22.7 mg U/l, similar to value for uranium nitrate; the sediment collected was not toxic to C. riparius larvae. The LOEC of effluent and uranium nitrate on HT(50) of D. rerio were similar (0.03 mg U/l), but larvae were more sensitive to uranium nitrate than to effluent. Our results suggest that other substances contained in the effluent could potentially be toxic to wildlife in association with uranium. In parallel, the modelling of the transfers based on uranium measurements in the surface water was used to fill data gaps and assess the impact along the river. These results provided an estimate of exposure conditions that occurred along the river. This approach allowed us to see that the risk to ecosystem during this incident was certainly low and concerned a short period of time, but it could have existed at least for some species.

Zebrafish exposure to environmentally relevant concentration of depleted uranium impairs progeny development at the molecular and histological levels

“…It is a main by-product of the nuclear fuel cycle, it is used as counterweights in the aircraft industry, in biological shielding for radiation protection and is used as armour penetrator in military conventional ammunitions. High levels of natural [8] and depleted uranium [9] have already been observed, either in the vicinity of former mining sites or after accidental spillage of industrial sites. With the growing world nuclear energy demand, DU concentration in the geosphere is expected to increase in the next decades [10], raising concerns on the long-term effects of this chemical on the environment.…”

Hepatic transcriptomic profiling reveals early toxicological mechanisms of uranium in Atlantic salmon (Salmo salar)

“…Especially near the U mill tailings, U dust particles can be easily washed out by precipitation into surface water. The U concentration in surface water may range from 0.02 μg/L to 3 mg/L, depending on the geological conditions [2–4]. Uranium may accumulate in bone, liver and kidney of an organism, but may not be biomagnified [5].…”

Biology-Based Modeling To Analyze Uranium Toxicity Data on Daphnia magna in a Multigeneration Study

“…Recent studies have investigated chronic toxicity of waterborne depleted uranium on the life cycle and physiology of Daphnia magna . , Uranium is naturally found in freshwaters at concentrations ranging from ≤6 μg L −1 to 2 mg L −1 in the vicinity of uraniferous sites. Locally, these levels are largely exceeded due to anthropogenic activities associated with the use of uranium in nuclear fuel or weapons. − Uranium is a heavy metal and its chemical toxicity is commonly considered of much greater concern in comparison to its radiotoxicity. , Uranium toxic effects were showed to increase across three successively exposed generations, highlighting the necessity for multigenerational toxicity tests in support of ecological risk assessment . Measuring feeding rates with a radiomarker technique showed that a reduction in carbon assimilation was probably involved in the response to uranium.…”