Assessing Acute Toxicities of Pre- And Post-Treatment Industrial Wastewaters With Hydra Attenuata: A Comparative Study of Acute Toxicity With the Fathead Minnow, Pimephales Promelas

Abstract

This study was undertaken to (a) determine wastewater treatment effectiveness using two freshwater organisms (b) compare acute toxicity results from the two species exposed to the wastewaters, and (c) link acute and potential develop mental toxicity of wastewaters in one organism The acute toxicities of several pretreatment and post treatment industrial waste water samples were evaluated with adult Hydra attenuata (92 or 96 h exposure) and fathead minnows (96 h exposure) The acute LCSOs agreed closely when results in Hydra attenuata were compared with those from fathead minnow tests Acute LC50s ranged from 3 to > 100% of sample with hydra, and from 1 0 to > 100% of sample with fathead minnows The results provided strong evidence of treatment effectiveness because toxicity decreased with progressive stages of treatment Previously the Hydra Developmental Toxicity Assay (Hydra Assay) was used as a prescreen mainly for in vitro assessment of developmental toxicity with pure compounds and to prioritize toxicants according to selective toxicity to the developing embryo (A/D ratio) Recently we modified the assay for testing natural waters and wastewaters, hence, some of the wastewater samples also were tested for their developmental toxicity In this case, the relative selective toxicity (A/D ratio) of these wastewater samples ranged from 0 7 to 2 1, indicating that no sample was uniquely toxic to the developing embryo, although acute toxicity was manifested Over all, our results indicate the Hydra Assay functions appropriately In assessments of acute and developmental toxicity of indus trial wastewaters and may be a simple and useful tool in a battery of tests for broader scale detection of environmental hazards

13th Meeting of the Scientific Group on Methodologies for the Safety Evaluation of Chemicals (SGOMSEC): alternative testing methodologies for ecotoxicity.

“…The regeneration assay using body segments appears to be ineffective for the prescreening of chemicals for selective developmental toxicity hazard-potential; however, the use of the artificial embryo in the Hydra developmental toxicity assay agrees with published vertebrate studies (25)(26)(27)(28)(29) (30).…”

Hydra, a model system for environmental studies

“…Another study investigating the developmental hazards of industrial wastewater samples tested on H. vulgaris resulted in a minimal effect concentration (MEC) (based on both adult morphology and artificial embryo toxicity) of 6-31% effluent (Fu et al, 1991). These authors also reported 72 and 96 hour LC 50 ranging from 2.7 to >100% for industrial wastewaters, which closely matched the LC 50 values of fathead minnow (Pimephales promelas) bioassays run in parallel (Fu et al, 1994). As part of a battery of bioassays, Hydra species have been used to assess the toxicity of vinasse (a byproduct of the sugar industry) (Ferreira et al, 2011), animal feed additives (Marroquin-Cardona et al, 2009) and pesticides (Castillo et al, 2006).…”

“…Hydra have been successfully used to examine the teratogenic potential of several chemicals including effluents and water samples (Fu et al, 1991, Fu et al, 1994 and various chemicals (Johnson et al, 1986;Mayura et al, 1991;Yang et al, 1993;Bowden et al, 1995,) including endocrine disrupting compounds Pachura-Bouchet et al, 2006) and pharmaceuticals Quinn et al, 2008b;Quinn et al, 2009). Good correlation was found between the in vitro Hydra regeneration assay and teratogenicity in vivo, as reported by Bowden et al, (1995) and Wilby and Tesh (1990), who proposed it as a screening tool for teratogenicity.…”

“…In several studies the Hydra bioassay, particularly when chronic changes in morphology and reproduction rate were measured, was more sensitive than other bioassays undertaken with invertebrate, vertebrate and plant test organisms (Diaz-Baez et al, 2002;Ronco et al, 2002a;Arkhipchuk et al, 2006b;Oberholster et al, 2008). In particular, sub-lethal effects on Hydra morphology were found to be considerably more sensitive than lethal effects , closely matching the toxicity response of the fathead minnow (Fu et al, 1994) and are generally more sensitive than the Microtox test (Pardos et al, 1999). H. vulgaris is particularly sensitive to Cd and Cu, responding at similar concentrations to G. pulex, an indicator species of freshwater quality and with 48 and 72 hours LC 50 values showing similar sensitivity to Daphnia magna (Beach and Pascoe, 1998).…”

Isolation and Identification of Heavy Metal Tolerant Bacteria from Tannery Effluents

“…Most of these wastewaters are extremely complex mixtures containing inorganic and organic compounds 1 . The tannery operation consists of converting the raw hide or skin into leather, which can be used in the manufacture of a wide range of products.…”