Molecular toxicology deals with the effects of various chemical substances on living systems. Applications include that inn biotechnology, pharmaceuticals etc. It is concerned with the principles and methods of molecular and cellular biology as well as genomic sciences which have a major role in understanding principles of mechanistic toxicology.

Toxicologic pathology combines the disciplines of toxicology and pathology Toxicologic Pathology is for the promotion of human, animal, and environmental health spreading through the knowledge, techniques, and guidelines to improve the understanding and practice of toxicologic pathology. This field is to identify the effects of test articles like drugs, chemicals and other therapeutic devices on research models.

Genetic toxicology deals with the study of effects of different physical, chemical and biological substances on genetic material. It identifies the possible reasons for occurrence of birth defects, heritable mutations and carcinogenesis. Mutations are caused due to genetic damage. The property of the chemical agent which causes the genetic damage is studied under genotoxicity. Mutations are the main cause for carcinogenesis.

The study of how drugs exert effects on the biological systems is termed as pharmacology. Pharmacologists mainly deal with the identification of drug targets, mechanisms of drug action and also the changes which the drug undergoes in the body. Applied Pharmacology deals with the application of the basic aspects of pharmacology. 

Human Toxicology includes all the aspects of experimental and clinical studies of functional, biochemical and structural disorder. The Clinical Toxicology is the measurement and interpretation of concentrations of drugs and other toxic substances in human biological fluids for the purpose of patient care, this testing is necessary when there is multiple drug ingestion is involved, the effects of one drug may mask the clinical signs and symptoms of the effects of other drugs. 

Forensic toxicology is the analysis of the biological samples for the presence of toxins, including drugs. It is of forensic science deals with the study of toxic substances or poisons, which also has their chemical composition, preparations and identification. It includes the manner in which the body responds to their presence and the factors which determine the drug safety and effectiveness.

Environmental toxicology is the study of the harmful effects of various chemical, biological and physical agents on living organisms at different levels of ecosystem. Many sources lead to environmental toxicity which includes toxicants from pollutants, insecticides, pesticides, fertilizers, industrial and metallic toxicants. All these agents have a profound influence on the living organisms. This may result in the imbalance of ecosystem.

Drug Toxicology is deals with the safety evaluation of drugs. The primary objective of toxicology studies in the process of development in drug is to evaluate the safety of potential drug. This is done using relevant animal models and validated procedures. Drug toxicology main aim is to translate the animal model responses into an understanding of the risk for human.

Toxicology is a rapidly expanding concept with immense research done on several emerging topics. A new advance always breaks through.

Pharmacology mainly deals with the study of the drugs their uses, effects, the mechanisms of action. Thus it mainly studies the Pharmacokinetics and Pharmacodynamics of the drug. Toxicology is the study of the adverse effects of chemicals which also includes drugs on living systems and which are mean prevent such effects. In addition to the therapeutic agents, toxicologists examine many environmental agents and chemical compounds that are synthesized by humans.

Toxicology consulting is the evaluation of the potential for chemical exposures to affect human and environmental health and welfare. Human beings come into contact with chemicals on a daily basis, which are naturally present in the environment or may be made by humans. Toxicology Consultants are who Provides industry health or environmental managers with information and advices them regarding the health risks of their chemical products to human beings and the environment. 

Pharmacovigilance is the pharmacological science which deals with identifying, collecting, detecting, assessing, monitoring, and preventing adverse effects caused by pharmaceutical products. It mainly focuses on adverse drug reactions or ADRs, which are unintended pharmacological responses. Adverse drugs reactions may be caused due to overdose misuse or abuse of drugs. Pharmacoviglilance departments go into an agreement with patients and health care providers to obtain data which forms their medical literature.