Page 15 - Professorial Lecture - Prof Omoregie

ECOTOXICOLOGY AND MARINE SCIENCE

Distinguished Ladies and Gentlemen, ever since humans started exploiting and
modifying resources from the environment, the issues of waste generation and
disposal have been a great concern. Associated with these wastes are substances
having deleterious effects on the environment; in other words, several
components within the waste are ‘poisons’ causing ‘toxic’ effects on living
organisms.

The scientific study of these poisons and the toxic effects is what comprises the
Science of Toxicology. Toxicology is a very broad term, which, according to the
Society of Toxicology (SOT), is defined as ‘the study of the adverse effects of
chemical, physical or biological agents (‘toxicants’) on living organisms and the
ecosystem (‘ecotoxicology’), including the prevention and amelioration of such
adverse effects’.

Toxicity is the adverse end product of a series of events that is initiated by
exposure to chemical, physical or biological agents (‘pollution’). According to SOT
(2005), toxicity can manifest itself in a wide array of forms, from mild biochemical
malfunctions to serious organ damage and mortality. These `events may be
reversible or irreversible depending on the nature of exposure and prevailing
environmental conditions at time of exposure (Omoregie, 1998).

The broad scope of Toxicology, from the study of fundamental mechanisms to the
measurement of exposure, including toxicity testing and risk analysis, requires an
extensively interdisciplinary approach as noted by SOT (2005). This approach
utilizes the principles and methods of other disciplines, including molecular
biology, chemistry (analytical, organic, inorganic and biochemistry), physiology,
medicine (veterinary and human), computer science and informatics.

The study of these toxicants (‘environmental pollutants’ – as they change the
natural status of the environment), their effects on aquatic organisms and
dynamics within the ecosystem, is the special discipline referred to as Aquatic
Ecotoxicology (Marine Ecotoxicology - when restricted to the Marine
Environment).
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