To understand the physiological effects of selected chemicals, which professional would provide the most useful information?

• A. Chemist
• B. Epidemiologist
• C. Pharmacologist
• D. Toxicologist

Answer: (D)

Understanding how chemicals affect the body at a physiological level is best addressed by a toxicologist. This professional focuses on how toxins interact with biological systems, including dose–response relationships, mechanisms of injury, metabolism, and factors that influence toxicity. Their work translates chemical properties into health risks and safety thresholds, helping to establish protective guidelines and regulatory standards. The other professionals have different primary focuses: a chemist deals with the composition and properties of chemicals, an epidemiologist examines disease patterns in populations, and a pharmacologist studies how drugs affect the body and their therapeutic uses. For information specifically about the harmful physiological effects of various chemicals, the toxicologist is the most relevant source.