A common practice in Tunisia is to discharge untreated industrial effluents directly into neighbouring water bodies or onto agricultural land. As a result the quality of some local streams and rivers has been degraded to the point where the water is not safe for human or livestock use or for irrigation. Textile, olive oil mill and pharmaceutical wastewaters (TW, OMW and PW) are an environmental pollutants extremely toxics to plants and other living organisms including humans. In previous work [3
mt-2 was revealed able to treat these effluents. However, we cannot accurately locate the toxicity of effluents and a key question arises is that such treatment leads to detoxification. The level of toxicity in the DNA, previously described [3
], may not be sufficient and does not reflect the toxicity of the other part of the body among other things the brain. In this work, a single dose of intraperitoneal administration of pharmaceutical wastewaters caused strongly clonic convulsions (230.5 onset of seizure) which are higher than the reference drug PTZ (180.16 onset of seizure). Despite the difference in chemical structure between PTZ and drugs of PW contents, the latter has a higher convulsion effect. This could be explaining by several hypotheses. In fact, synergic effects between some or all drug of PW contents are responsible for the convulsion effects, or, metabolites deriving from UV or VIS degradation of these drug when released into the environment could show a similar chemical structure than PTZ, and consequently are responsible for the observed convulsion effect. Then, PW could induce epilepsy; this later is one of the most common serious neurological conditions. According to Aalbers et al. [7
] and Luisa [8
] the forbrain is involved in the expression of clonic seizures, whereas the activation of brainstem structures participates in the expression of the tonic component. Convulsive seizures could be attributed to the presence of drugs in PW which blocked γ-aminobutyric acid (GABA) receptor Cl-
]. However, the two other effluents, TW and OMW, do show any convulsing effect. Seizures have traditionally been recognized as a symptom of abnormal neuronal synchronization, and until recently have been thought to be a result of aberrant synaptic communication [9
]. This idea was confirmed by other models such as visceral pain. Among the several models of visceral pain, writhing test has been mostly used as a standard screening method [11
]. All tested wastewaters are reveled able to induce algogenic effects. In fact intraperitoneal administration of the three industrial wastewaters produces significant abdominal contractions throughout the entire period of observation. Similarly, the PW has been proven to be very active and strongly induces pain that result in a remarkable number of cramps (44 ± 2), well above the PBQ (drug reference) (39 ± 2). TW and OMW also induce effects algogenic but lesser degree. The algogenic effect could be attributed especially to the presence of pharmaceutical drug, dyes and phenolic compounds in the PW, TW and OMW, respectively.
The induction mechanism of algogenic effects by these products could be defined according to two hypotheses. Molecules contained in effluents acts indirectly by inducing the release of endogenous mediator, which stimulates the nociceptive neurons sensitive to NSAIDs (non-steroidal anti-inflammatory drugs) and/or opioids [12
] but these molecules-induced writhing response could believed to be produced by the liberation of endogenous substance(s), notably metabolites of the arachidonic cascade [12
According to the toxic effects observed in these effluents, the search of a treatment is imperative. However, removal of numerous classes of pharmaceuticals, textile and olive mill from the industrial wastewater, using conventional wastewater treatment, is incomplete. In this work we suggested that improvement of this situation would require the application P. putida to the treatment of these effluents. This is particularly important for the treatment of industrial effluents, released from pharmaceutical, textile and olive mill industries, which can contain rather high concentrations of toxic compounds. In fact, any toxicity was observed when tested effluents treated by P. putida mt-2.