What is Behavioural Toxicology?

Behavioural Toxicology?

The study of behavioural modifications brought on by exposure to environmental toxins is known as behavioural toxicology. It is a composite science with elements in both toxicology and cognitive science. Neurocognitive toxicology may be a suitable word to define this field of toxicology given the growing overlap between the behavioural sciences and neurology.

This study shows us how medicines, chemicals, or other environmental factors can alter behaviour. Behavioural toxicologists employ changes in behaviour, together with changes in sensation, mood, cognitive function, and motor coordination, to pinpoint hazards associated with exposure to probable toxins those are responsible for this change. They also discover the methods through which toxins can severely alter the central nervous system.

Scientists and governmental entities can make use of data from behavioural toxicology to set limitations on the quantities of toxicant exposure that are appropriate in the environment. Epidemiological data, scientific tests involving human or animal respondents, and analysis-based experiments are some of the strategies utilised in toxicology.

Also Read: Forensic Toxicology and Sample Testing

Behavioural Toxicity in different Poisoning

Metals

A. Mercury

The initial behavioral indications of mercury poisoning in humans include-

1. Irritability
2. Anxiety
3. Insomnia
4. Hyper-reactivity
5. Emotional instability
6. Neuroticism
7. Introversion

The victim is oblivious of the subtle shifts of mood and personality, which result in worsening social difficulties, susceptibility to depression, and chronic anxiety.

B. Aluminium

The initial behavioural indications of aluminium poisoning in humans include-

1. Complications with visual discrimination and reversal stimulus.
2. Irritability
3. Social Anxiety

The hippocampus of the animals contained the greatest levels of aluminium. It appears that this region is particularly good at concentrating other metals like lead and zinc.

Numerous studies have suggested that aluminium exposure may have neurotoxic effects as a significant factor in the onset of Alzheimer’s disease. The discovery of elevated aluminium intensities in the brains of Alzheimer’s sufferers, suggests that metal intoxication may contribute to the phenomenon of dialysis dementia i.e. altered conduct and dementia in patients receiving dialysis, and a number of animal studies with rabbits, rats, and cats are some examples of evidence corroborating this theory.

Organic Solvents

Organic solvents have undergone substantial research in order to determine whether they have any early neuropsychiatric consequences. As a result of this research, the serious disease organic solvent syndrome (OSS) is discovered. The sole cause of this disease is excessive exposure to organic chemical solvents. The signs and symptoms of this toxicity are remarkably comparable to those reported after exposure to heavy metals, and they include:

1. Lack of initiative
2. Inability to focus
3. Excessive fatigue
4. Emotional instability
5. Headache
6. Sexual dysfunction

Gases

The neurobehavioral impact of carbon monoxide, carbon dioxide, and multiple other gases on the CNS’s functionality includes:

1. Lack of initiative,
2. Inability to concentrate,
3. Excessive fatigue,
4. Emotional instability,
5. Headache
6. Sexual dysfunction

Feingold Hypothesis: A Difficulty for Behavioural Toxicity Studying

The notion that certain people may be overly vulnerable to certain chemicals is one of the most problematic challenges plaguing behavioural toxicology. The Feingold hypothesis, named for its discoverer, asserts that certain dietary supplements and colouring agents may contribute to children’s hyperactivity. A tiny percentage of youngsters who are hyperactive do exhibit high hyper-susceptibility to certain food supplements. Hence, the study of behavioural toxicity does not show the proper results for this hyper-activity found in those specific children.

Other Limitations

There are at least two explanations why human behavioural studies of the effects of hazardous chemical exposure on behavioural have trailed behind animal experiments. First, exposing human beings to potentially harmful substances has ethical boundaries. The majority of the approaches used to evaluate the consequences of exposure are not responsive to low-level exposure, which is the second issue. The discovery that behavioural alterations may be the earliest sign of excessive exposure to a hazardous agent grants behavioural toxicology some potential significance.

Conclusion

Scientists have long been aware that chemicals have an impact on both human and animal behaviour. Additionally, because of recent developments in technology and computation, researchers are becoming more and more aware of the detrimental effects that a variety of pollutants and other environmental stressors have on organismal behaviour and the subsequent environmental and economic findings in earthbound and marine ecosystems. Additionally, there is growing criticism that regulatory ecotoxicology does not appropriately take behaviour into account, mostly for the absence of regulated toxicity measures.  As a result, numerous psychological and developmental ecotoxicology research have been left out of chemical risk evaluation.