Acute toxicity of a glyphosate herbicide, Roundup®, to two freshwater crustaceans

Abstract

The acute toxicity of a glyphosate herbicide Roundup ® , contaminating freshwater ecosystems in Sri Lanka was investigated with two species of the most common freshwater crustaceans: calanoid copepod (Phyllodiaptomus annae Apstein) and decapod shrimp (Caridina nilotica P. Roux). LC50 values in adult males were determined using standard toxicity assays under static conditions. The 48h LC50 value for P. annae was estimated as 1.06 mg/L and the values of 72 h and 96 h LC50 for C. nilotica were 107.53 and 60.97 mg/L, respectively. The present study reveals that Roundup ® may cause a significant impact on native non-target organisms. Further studies are needed to establish the toxic effect of Roundup ® to the very important structural group in the aquatic ecosystems in Sri Lanka.

Acute toxicity of glyphosate on various life stages of calanoid copepod, Pseudodiaptomus annandalei

“…Inhibition of EPSPS enzyme production can be fatal to plants and animals. Ashoka Deepananda et al (2011) showed that 24 h exposure of glyphosate can kill 50% of Phyllodiaptomus annae as low as 1.059 mg/L. The present results showed that adult stage of P. annandalei (24 h LC 50 ; 11.70 mg/L Gly) demonstrated slightly better tolerant to glyphosate compared to the adult stage of Phyllodiaptomus annae as reported previously.…”

“…This could be attributed to variation in many biotic and abiotic factors such as geographical distribution, species, innate immune response etc. For instance, P. annae was collected from the rivers of Sri Lanka (Ashoka Deepananda et al, 2011), while P. annandalei in this study was collected from an estuary in Matang river, Kuala Sepetang, Perak, Malaysia. The climate and variation in abiotic environmental factors such as temperature, salinity, and diet preference could be direct or indirectly influent the biological reaction, metabolism and physiological changes of the copepods.…”

“…Mortality was confirmed through observation under a microscope, subsequently dead individuals were transferred to new Petri dishes. To confirm the fatality, an individual is considered dead when no sign of heartbeat was observed and the individual did not show any life responses towards teasing using a tip (Ashoka Deepananda et al, 2011). All treatments were performed in triplicate.…”

“…shrimp and some cladocerans. A study showed that 72 h and 96 h LC 50 of the decapod shrimp Caridina nilotica was recorded at 107.53 and 60.97 µg/L respectively after the exposure to glyphosate (Ashoka Deepananda et al, 2011). Cladocerans e.g.…”

ISOLATION AND CHARACTERIZATION OF A MOLYBDENUM-REDUCING AND GLYPHOSATE-DEGRADING Klebsiella oxytoca STRAIN SAW-5 IN SOILS FROM SARAWAK

“…Numerous studies have shown that the formulations and surfactant additives are usually more toxic to test species (Barceló and Hennion, 1995;Giesy et al, 2000). Studies on various organisms such as nematode, juvenile frogs, freshwater crustaceans, microalgae and sturgeons showed that they exhibit significant toxicity to these organisms (Achiorno et al, 2008;Bernal et al, 2009;Ermis and Demir, 2009;Deepananda et al, 2011;Filizadeh and Islami, 2011;Bates and Edwards, 2013;Piola et al, 2013). Removal of glyphosate from soils is best carried out by bioremediation often employing glyphosate-degrading bacteria as the low con-centration of glyphosate in polluted soils make other form of remediation such as chemical and physical more expensive and unpractical.…”