Mechanisms of Toxicity and Cellular Damage

Reactive Oxygen Species (ROS)

Formation of oxidative damage to DNA, lipids, and proteins.

Covalent Binding to Macromolecules

Toxicants/metabolites bind to DNA, RNA, or proteins, disrupting function and potentially causing mutations.

Disruption of Cellular Energy Production

Interference with mitochondrial production, leading to energy depletion and cell death.

Calcium Dysregulation

Disruption of calcium homeostasis activates harmful enzymes and damages mitochondria.

Immune System Dysfunction

Toxicants suppress or hyperactivate the immune system, leading to infections, allergies, or autoimmunity.

Endocrine Disruption

Interference with hormone signaling, synthesis, or receptor binding, altering physiological functions.

Genotoxicity

Direct or indirect damage to genetic material, causing mutations or chromosomal aberrations.

Receptor Interaction and Signaling Pathway Disruption

Toxicants act as receptor agonists/antagonists, impairing normal cell signaling.

Membrane Damage

Disruption of cellular/organelle membranes leads to leakage of contents and cell death.

Apoptosis and Necrosis

Activation of programmed (apoptosis) or uncontrolled (necrosis) cell death pathways.

Neurotoxicity

Interference with nervous system function through disrupted signaling, transport, or structure.

Carbon tetrachloride (CCI)

Causes lipid peroxidation.

Paraquat

Induces lung toxicity.

Aflatoxin B1

Binds DNA, causing mutations.

Acetaminophen overdose

NAPQI binds liver proteins.

Cyanide

Inhibits cytochrome c oxidase.

Rotenone

Blocks mitochondrial complex I.

Glutamate (excitotoxin)

Causes neuronal calcium influx.

Mercury

Alters signaling.

Asbestos

Causes chronic lung inflammation and fibrosis.

Dioxins

Suppress immune function.

BPA

Mimics estrogen, affecting reproduction.

DDT

Disrupts androgen and estrogen signaling.

Ionizing radiation

Induces DNA strand breaks.

Benzo[a]pyrene

Forms DNA adducts.

Nicotine

Overstimulates nicotinic receptors.

Botulinum toxin

Blocks release of neurotransmitters.

Snake venom toxins

Degrade phospholipids in membranes.

Ethanol

Increases membrane fluidity and induces liver apoptosis with chronic exposure.

Lead

Causes necrosis in kidneys.

Organophosphates

Inhibit acetylcholinesterase.

Methylmercury

Damages developing neurons.