Acute toxicity evaluation of olive oil mill wastewaters: A comparative study of three aquatic organisms

Abstract

Acute toxicity of olive mill wastewaters (traditional and continuous processes) collected from different regions of Portugal was evaluated using three test species (Vibrio fischeri formerly Photobacterium phosphoreum, Thamnocephalus platyurus, and Daphnia magna) and correlated with several physical and chemical parameters. Acute toxicity of these effluents, expressed in LC50 or EC50, ranged from: 0.16 to 1.24% in Microtox test, 0.73 to 12.54% in Thamnotoxkit F test, and 1.08 to 6.83% in Daphnia test. These values reflect the high toxicity of the olive mill wastewaters to all test species. Statistical analysis of the results shows a high correlation between the two microcrustacean bioassays. Microtox test did not correlate significantly with the other bioassays used. A significative correlation (p≤0.05) could also be established between L(E)C50 obtained in the microcrustacean tests and some physicochemical parameters of the effluent. ©1999 John Wiley & Sons, Inc. Environ Toxicol 14: 263–269, 1999

GC-MS, FTIR and 1H ,13C NMR Structural Analysis and Identification of Phenolic Compounds in Olive Mill Wastewater Extracted from Oued Oussefrou Effluent (Beni Mellal-Morocco)

“…Among these organic substances, the rate of phenolic compounds is relatively high and is characterized by its great variety and complexity as part of OMWW [2,[4][5]. In this way, several studies show that phenolic compounds present a major disadvantage for the environment and are primarily responsible for toxicity [11] and phytotoxicity [6,12]. In addition, it is, in fact, a poor biodegradability and a high phytotoxicity due to the presence of a large amount of polyphenols [2], aromatic compounds, free fatty acids and inorganic salts (mainly potassium salts) [13].…”

Biodegradation of Olive Mill Wastewater by Trichosporon Cutaneum and Geotrichum Candidum

“…OMW is recalcitrant to conventional wastewater treatment, and its management and disposal present a serious environmental problem (8). The removal of phenolic compounds is therefore the fi rst step in OMW biodegradation and detoxifi cation (24).…”

“…The phenolic fraction is recalcitrant to biodegradation and is responsible for several biological affects including phytotoxicity and antibiosis (4,6,7). Literature also reports that OMW toxicity is owed to high organic load, phenolic compounds, free fatty acids, low pH, low dissolved oxygen (DO), high total suspended solids, and tannins (7)(8)(9). Some claim that OMW toxicity does not depend on extraction procedure (8), while others report that OMW from the continuous process is less toxic that from the traditional (10).…”

“…Literature also reports that OMW toxicity is owed to high organic load, phenolic compounds, free fatty acids, low pH, low dissolved oxygen (DO), high total suspended solids, and tannins (7)(8)(9). Some claim that OMW toxicity does not depend on extraction procedure (8), while others report that OMW from the continuous process is less toxic that from the traditional (10). The concentration of phenolic compounds in OMW may reach 5 g L -1 to 10 g L -1 due to higher solubility in the water phase than oil (10)(11)(12).…”

“…A number of different microorganisms and processes have been tested to treat OMW (13). Biological processes investigated for OMW treatment are aerobic and anaerobic (6)(7)(8)(9)(10)(11). The major problem with anaerobic processes is the inhibition of anaerobic microorganisms by phenolic compounds and long-chain fatty acids present in OMW and their persistence in effl uent (13).…”