Why Epichlorohydrin can cause cancer?

Epichlorohydrin the mechanism of carcinogenesis

The carcinogenic mechanism of epichlorohydrin (ECH) involves several steps that lead to its toxic and potentially cancer-causing effects in humans. When epichlorohydrin enters the body, it can be metabolized into reactive intermediates that can damage DNA and proteins, leading to mutations and other forms of genetic damage that can contribute to the development of cancer.

Here’s a more detailed breakdown of the steps involved in the carcinogenic mechanism of epichlorohydrin:

1. Absorption: Epichlorohydrin can be absorbed through the skin, inhalation, or ingestion. Once inside the body, it can be distributed to various organs and tissues.
2. Metabolism: Epichlorohydrin is metabolized in the body primarily in the liver. The metabolism of epichlorohydrin results in the formation of reactive intermediates, including chlorocholine and chloroacetaldehyde. These intermediates can react with cellular macromolecules, such as DNA and proteins, leading to genetic damage and potentially cancer.
3. DNA and protein damage: The reactive intermediates formed from the metabolism of epichlorohydrin can cause various types of damage to DNA, such as cross-linking, DNA strand breaks, and base modifications. Similarly, these intermediates can also modify proteins, which can affect their structure and function. This damage to cellular macromolecules can interfere normal cellular processes and lead to mutations and other forms of genetic damage.
4. Mutation and cancer: The genetic damage caused by epichlorohydrin can result in mutations in critical genes that control cell growth and division. If these mutations are not repaired properly, they can lead to the uncontrolled growth of cells, which can ultimately lead to the development of cancer.

The carcinogenic mechanism of epichlorohydrin can vary depending on the species and the exposure conditions. Additionally, individual susceptibility to epichlorohydrin-induced cancer can vary based on factors such as genetic background, lifestyle, and overall health.

Related cancers

Based on animal studies, epichlorohydrin has been associated with the following types of cancer:

1. Liver Cancer: Rodents exposed to epichlorohydrin have shown an increased incidence of liver tumors.
2. Kidney Cancer: Some animal studies have suggested a link between epichlorohydrin exposure and kidney tumors.
3. Skin Cancer: There is evidence from animal studies that epichlorohydrin can increase the risk of skin tumors.
4. Lung Cancer: Inhalation exposure to epichlorohydrin in animals has been associated with an increased risk of lung tumors.
5. Leukemia: Some studies in animals have indicated that epichlorohydrin may be associated with an increased risk of leukemia, a type of cancer of the blood-forming tissues.

The mechanisms by which epichlorohydrin causes cancer in animals may not be directly applicable to humans, and the cancer risks may vary with the route and level of exposure, as well as individual susceptibility. The limited human data available has not provided strong evidence of a link between epichlorohydrin exposure and cancer. However, due to the potential risks identified in animal studies and the presence of genotoxic properties, precautions are taken to minimize occupational and environmental exposure to epichlorohydrin.

Potential routes of exposure

Epichlorohydrin (ECH) is primarily used in industrial settings, and as a result, most exposure to it occurs in occupational settings rather than in everyday life. However, there are some potential routes of exposure that could occur outside of industrial environments:

1. Environmental Exposure: Epichlorohydrin can be released into the environment through industrial emissions, wastewater discharge, and the disposal of products containing the chemical. This can result in low-level exposure to the general population through air, water, and soil contamination.
2. Consumer Products: Although epichlorohydrin is mainly used in industrial processes, it can be found in some consumer products, such as adhesives, varnishes, and coatings. These products may contain residual amounts of epichlorohydrin, which could potentially be released during use.
3. Food Packaging: Epichlorohydrin has been used in the production of food packaging materials. While regulations are in place to limit the migration of the chemical from packaging into food, there is a potential for very low-level exposure through this route.
4. Drinking Water: Epichlorohydrin can be used in the treatment of drinking water and may be present in trace amounts in treated water. However, water treatment processes are designed to minimize the levels of residual chemicals, including epichlorohydrin, in the water supply.
5. Hobbies: Individuals involved in certain hobbies, such as model making or working with certain types of resins and glues, may come into contact with products containing epichlorohydrin.

Occupations that are at a higher risk of exposure to epichlorohydrin typically involve workers who are directly involved in the production, processing, or use of the chemical. Epichlorohydrin is widely used in various industrial applications, and as a result, certain jobs may have a greater likelihood of exposure. High-risk occupations include:

1. Chemical Manufacturing Workers: Employees in facilities that produce epichlorohydrin or use it as a raw material in the manufacturing of other chemicals are at risk. This includes workers in epoxy resins, glycerol, and other polymer production.
2. Industrial Maintenance and Repair Workers: These workers may be exposed to epichlorohydrin during the maintenance and repair of equipment and pipelines that transport or contain the chemical.
3. Plastics and Polymer Industry Workers: Epichlorohydrin is used in the production of certain types of plastics and polymers, so workers in these industries may be at risk.
4. Adhesive and Sealant Manufacturing: Workers involved in the production of adhesives and sealants that contain epichlorohydrin can be exposed to the chemical.
5. Paint and Coating Industry Workers: Epichlorohydrin may be used in the production of some paints and coatings, exposing workers in this industry to potential risks.
6. Water Treatment Plant Workers: Epichlorohydrin can be used in water treatment processes, so workers at these facilities may be at risk of exposure.
7. Laboratory Technicians: Researchers and laboratory workers who handle or analyze epichlorohydrin or products containing it are also at risk.
8. Hazmat Handlers: Workers involved in the transportation, storage, and disposal of hazardous materials, including epichlorohydrin, are at risk of exposure.

Workers in these and related industries to follow strict safety protocols, such as wearing personal protective equipment (PPE) and utilizing engineering controls to minimize exposure to epichlorohydrin. Additionally, employers should provide training on the proper handling of hazardous chemicals and implement comprehensive safety programs to protect their employees from potential health risks.

In the United States, the safety levels for epichlorohydrin are governed by the Occupational Safety and Health Administration (OSHA). According to the Centers for Disease Control and Prevention (CDC) and the National Institute for Occupational Safety and Health (NIOSH), the current OSHA Permissible Exposure Limit (PEL) for epichlorohydrin is an average weighted concentration (TWA) of 5 ppm (19 mg/m³) for skin exposure.

Additionally, NIOSH recognizes epichlorohydrin as a potential carcinogen and recommends wearing the most protective respirators at any detectable concentration. These standards and recommendations are in place to minimize the potential health hazards associated with epichlorohydrin exposure, particularly in occupational settings.