It is necessary to consider the criteria of toxicity in this case. Toxicity is revealed in mechanisms among which the following can be named: inhibition of oxygen transport, inhibition of electron transport chain, irritating, inhibition of enzymes, penetrating lipid structures, carcinogenic activity, teratogenic activity, radical damage, block of neurotransmission (Williams, James, & Roberts, 2002). As a result, for the estimation of substance toxicity, one should analyze the presence and force of the aforementioned factors.
The inhibition of oxygen transport occurs due to the excess of CO which is produced by the unfinished combustion of organic compounds. This variant can be easily disproved in two ways. Firstly, water is an inorganic matter. Secondly, water combustion is possible in an atmosphere of fluorine with the hydrogen fluoride and the oxygen fluoride release.
The inhibition of the electron transport chain is possible under the influence of zinc and cyanides, for example, hydrogen cyanide. Under these criteria consideration, it becomes obvious that the water molecule is not capable of being toxic. Inhibition of enzymes exists in the presence of hydrogen cyanide, hydrogen sulfide, and metals. The concentration of heavy metals in water, i.e. higher than the maximum permissible level, can be hazardous to health.
Penetration of lipid membranes occurs because of the activities of organic solvents like halogen derivatives and ethanol. It is well known that the solubility of ethanol in water is unlimited. Besides, everyone can experience the toxic effect of this solution.
The irritant action of the toxic gases can be caused by the presence of chlorine or fluorine as well as their derivatives. Taking clean water without the dissolved gases into account, the irritant action is impossible. There is a slight possibility of toxic effect if we consider the chlorinated water which is obtained during the water purification.
Water does not provoke carcinogenic and teratogenic effects. Toxicity could be a characteristic of the formation of the reactive oxygen species which can also be present in water. Block of neurotransmission happens under the effect of snake venoms and poisons. Thereby, water cannot be considered as a source of a harmful substance of this type.