Sub-Chronic and Chronic Toxicity

The length of sub-chronic and chronic toxicity studies typically ranges from three to 12 months during which a variety of adverse effects are examined including changes in body weight, organ weight, blood chemistry, and behavior. Researchers can use the study results to assess the potential risks of the test article to humans and to define safe exposure levels.

Chronic and Subchronic Toxicity Testing: Understanding the Differences

Among the various toxicity tests conducted, chronic and sub-chronic toxicity studies play a crucial role in assessing the long-term health effects of these substances. Both sub-chronic and chronic toxicity testing are essential for ensuring the safety of substances. Sub-chronic testing provides valuable insights into the immediate or short-term effects of a substance, while chronic testing reveals the long-term consequences of exposure.

  • Sub-chronic toxicity testing involves exposing animals to a substance for a period of 28 to 90 days. This type of testing is designed to identify any adverse effects that may occur after repeated exposure over a moderate period.
  • Chronic toxicity testing, on the other hand, involves exposing animals to a substance for a more extended period, often exceeding 90 days or even up to a year or more. This type of testing is aimed at detecting long-term, cumulative, and delayed adverse effects that may only manifest after prolonged exposure.

Drawing from the deep base of knowledge, our team of experts, technical experts, and regulatory advisers plan and conduct chronic and sub-chronic toxicity studies for small molecules and biologics. We are equipped to support your unique needs by creating a specialized core team of discovery, bioanalytical, toxicology, and regulatory advisers drawn from our global network of experts.

PCR samples ready for testing.

Your Guide to General Toxicology
This brochure outlines our general toxicology services, while sharing challenges and the advantages of having Charles River conduct your general toxicology services.
Read the Guide

Administration Routes in Chronic and Sub-Chronic Toxicity Testing

Routes of administration play a pivotal role in chronic and sub-chronic toxicity testing, serving as the pathways through which substances are introduced into the body for assessment. The selection of the appropriate route is of paramount importance, as it can significantly impact the accuracy and relevance of the toxicity study results.

Routes of administration offered include:

  • Oral (by gavage, capsule, or incorporated into formulated laboratory diets)
  • Dermal
  • Subcutaneous
  • Intravenous
  • Infusion
  • Intrathecal
  • Intramuscular
  • Ocular
  • Dietary
  • Inhalation

Additionally, we offer specialized administration routes and designs to cater to your specific requirements.

Request a Consult

Frequently Asked Questions (FAQs) for Sub-Chronic and Chronic Toxicity Studies

  • What is sub-chronic toxicity?

    Sub-chronic toxicity is a harmful effect from repeated exposure to a substance occurring typically after 28 to 90 days. Sub-chronic toxicity studies typically involve exposing animals to a substance through various routes, such as oral ingestion, inhalation, or dermal application. The animals are then observed for signs of toxicity, such as changes in body weight, behavior, or blood chemistry. Their tissues and organs are also examined for any abnormalities.

  • What is sub-chronic toxicity study?

    Sub-chronic toxicity studies, also known as sub-chronic toxicity tests, are preclinical studies that evaluate the potential harmful effects of a substance administered to animals for a moderate period, typically 28 to 90 days.

  • How long is a sub-chronic toxicity study?

    Sub-chronic toxicity testing typically lasts for 28 to 90 days. However, the exact duration of the study may vary depending on the substance being tested and the specific objectives of the study. Some sub-aachronic toxicity studies may last for as short as 14 days, while others may last for as long as 12 months.

  • How long is the study for chronic toxicity?

    Chronic toxicity studies typically last for 12 months or more. The exact duration of the study may vary depending on the substance being tested and the specific objectives of the study. Some chronic toxicity studies may last for as long as 24 months or even longer.

  • What is the difference between acute and chronic toxicity studies?

    Acute and chronic toxicity studies are two types of preclinical studies that are used to assess the safety of substances. The main difference between the two types of studies is the duration of exposure.

    • Acute toxicity studies involve exposing animals to a substance for a short period of time, typically 24 to 96 hours. These studies are designed to assess the immediate health effects of a substance, such as death, organ damage, or behavioral changes.
    • Chronic toxicity studies involve exposing animals to a substance for a prolonged period of time, typically 12 months or more. These studies are designed to assess the long-term health effects of a substance, such as cancer, reproductive toxicity, or developmental toxicity.