Oxidative stress and name two common toxicants that induce it.

• A. Oxidative stress is an imbalance between reactive oxygen species production and antioxidant defenses, leading to cellular damage; cadmium and benzene are common inducers.
• B. Oxidative stress is the same as inflammation.
• C. Oxidative stress only occurs in plants.
• D. Cadmium and benzene prevent oxidative stress.

Answer: (C)

Oxidative stress is the imbalance between production of reactive oxygen species and the body's antioxidant defenses, leading to damage to lipids, proteins, and DNA. Cadmium and benzene are classic examples of toxicants that induce this state: cadmium disrupts antioxidant systems—depleting glutathione and inhibiting key enzymes—while benzene metabolism produces reactive metabolites that generate ROS. Together, they push the cellular environment toward oxidative damage, which can contribute to various toxic effects.

Some statements don’t fit this concept: oxidative stress is not identical to inflammation, and it occurs in many organisms, not just plants. Additionally, cadmium and benzene do not prevent oxidative stress; they promote it by increasing ROS or weakening defenses.