The more toxic a material is, the smaller the amount of it is necessary to be absorbed before harmful effects are caused. The lower the toxicity, the greater the quantity of it is necessary to be absorbed.
These values are called LD50 lethal dose or LC50 lethal concentration , and are usually given in weight of material per kg of body weight or airborne concentration of material per set time period respectively. Toxicity is an inherent property of the material. A material may be very toxic, but not hazardous, if it is handled properly and is not absorbed into the body. On the other hand, a material may have a very low toxicity, but be very hazardous. In order for toxicants to affect the human system either they must cause damage to external tissues, such as the skin or eyes, or they must be able to enter the body by some mechanism.
There are three primary routes of entry into the body: ingestion, skin or eye absorption, inhalation and injection. Ingestion- This means taking a material into the body by mouth swallowing. Ingestion of toxic materials may occur as a result of eating in a contaminated work area. Absorption- Substances that contact the eye and the skin may be either absorbed into the body or cause local effects.
For the majority of organic compounds, the contribution from skin absorption to the total exposure should not be neglected. Inhalation- This means taking a material into the body by breathing it in. These materials have toxic effects but these effects may be delayed. The D2 division also has two subdivisions that separate "Toxics" and "Very Toxics". The "Toxic" group here also includes products that produce immediate but less serious reversible effects. The goal of the Globally Harmonized System of Classification and Labelling of Chemicals GHS is to provide a harmonized approach to classifying chemical hazards as well as communicating health and safety information e.
The intent is to have all countries using similar chemical classification, labelling and communication guidelines in order to reduce errors and misunderstandings. Under the GHS system, there are three major hazard groupings -- physical, health and environmental. Toxic materials are categorized under the Health Hazards. Some of the toxic and very toxic materials will have characteristics that place them in more than one class or group e.
The GHS system has set up a method for classifying toxic and very toxic materials using the following health hazard classes:. The GHS classification system is somewhat more complex than WHMIS and a classification of "toxic" in one system does not necessarily translate directly into the other. While the GHS system does goes into more detail regarding the classification of toxic materials than WHMIS does, it does not change the actual hazard associated with the material.
Add a badge to your website or intranet so your workers can quickly find answers to their health and safety questions. Although every effort is made to ensure the accuracy, currency and completeness of the information, CCOHS does not guarantee, warrant, represent or undertake that the information provided is correct, accurate or current.
CCOHS is not liable for any loss, claim, or demand arising directly or indirectly from any use or reliance upon the information. OSH Answers Fact Sheets Easy-to-read, question-and-answer fact sheets covering a wide range of workplace health and safety topics, from hazards to diseases to ergonomics to workplace promotion.
Search all fact sheets: Search. Type a word, a phrase, or ask a question. May cause headache, nausea, dizziness, drowsiness, incoordination and confusion, unconsciousness and death. Causes skin and eye irritation. How do we learn how chemicals affect health? Human Exposures: Information about human exposures that have occurred at work or by accident is very useful, even though it may be incomplete.
For example, if a person has been exposed to more than one substance, it may be hard to find out exactly which substance caused a health effect. Also, some health effects such as cancer don't appear until many years after the first exposure, making the cause of the disease hard to determine.
Even when the substance that caused the health effect is known, the exact dose that caused the effect may not be. Animal Studies: Many toxicity tests are done on animals. Animal tests are often good indicators of chemical toxicity in humans even though animals may not react exactly like people.
Many things are considered when applying the results of animal toxicity tests to humans. For example, animals are smaller, they have shorter lifespans and their bodies sometimes handle chemicals differently from humans.
Large doses are used in the animal studies to see if there will be any effect. When guidelines or standards for human exposure to chemicals are developed, these differences and others are taken into account. What can happen if you are exposed to a chemical? Area of the Body Affected: Chemicals can affect any system in the body, including respiratory nose, air passages and lungs , digestive mouth, throat, stomach, etc.
Some chemicals, like acids, are nonspecific and cause damage on direct contact. Other chemicals, like gasoline, can be absorbed into the blood, and carried throughout the body.
Some chemicals affect only certain target systems or target organs. They can occur directly at the site of contact or elsewhere in the body. For example, inhaled ammonia can irritate the linings of the nose, throat and lungs. Alcohol can cause dizziness. Immediate health effects are sometimes reversible and may disappear soon after the exposure stops. However, some immediate health effects do not go away; acute exposure to a corrosive substance, such as battery acid, may cause permanent damage to skin or eyes.
Protect Yourself Even though chemicals we use or are exposed to every day can be toxic, you can protect yourself and your family from chemical exposures. Before you use a product, read the label carefully and follow the instructions. Pay attention to warnings on the label. Use proper ventilation. Ventilation means getting fresh air into your home or workplace.
When using strong chemicals, open your doors and windows whenever the weather permits. When you use a toxic chemical indoors, you may wish to blow air out the window with a fan. Have another window or door open to let fresh air into the room.
If you use chemicals in your hobbies, use them outdoors or in a well- ventilated area away from your living space. Wear appropriate protective gloves when handling chemicals. If you use substances that are harmful to breathe like fiberglass which can lodge in the lungs , use an appropriate mask.
Store chemicals safely and out of the reach of children. Label all containers and do not store liquids in commonly used household containers such as soda bottles or food cans. If clothes become soiled while handling chemicals, change the clothes as soon as possible to reduce exposure.
Wash soiled clothes separately; then run the machine through a rinse cycle to clean it before washing more clothes. If you must use a toxic substance, buy only the amount needed so there will be less material left for storage or disposal.
Try to avoid using a toxic substance. If that is not possible, choose products that have less toxic ingredients. For example, water-based paints are generally less toxic than oil-based paints.
Indoor air can contain chemicals from outside air, soil or water. Radon, a naturally occurring radioactive gas, can affect your health. It enters homes through holes or cracks in basement floors or walls.
Learn how to test for radon. While not all hazards associated with every chemical and toxic substance are addressed here, we do provide relevant links to other pages with additional information about hazards and methods to control exposure in the workplace.
OSHA's Hazard Communication Standard HCS is designed to ensure that information about chemical and toxic substance hazards in the workplace and associated protective measures is disseminated to workers.
In order to ensure chemical safety in the workplace, information about the identities and hazards of the chemicals must be available and understandable to workers. Employers are required to identify and evaluate the respiratory hazard s in their workplaces. Here is an explanation of some of the different levels. OSHA sets enforceable permissible exposure limits PELs to protect workers against the health effects of exposure to hazardous substances, including limits on the airborne concentrations of hazardous chemicals in the air.
Approximately PELs have been established. However, many of these limits are outdated. Also, there are many substances for which OSHA does not have workplace exposure limits.
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