Decoding SDS Series Section 3: Composition
What should be listed in Section 3 of an SDS?
After establishing what hazards are present in a chemical, Section 3 of an SDS identifies the ingredients contained in the product. These ingredients may include stabilizing additives, possible impurities, and “trade secrets.”
A trade secret is a combination of chemicals that give the producer a competitive advantage over other competitors. Naturally, they do not wish to share this information. As long as the hazards present along with possible exposure effects are disclosed, simply listing “trade secret” is acceptable.
Substances and mixtures have two different lists of required information. If the product is a substance, required information in this section consists of the chemical name, common name and symptoms, impurities and stabilizing additives, and the Chemical Abstract Service (CAS) number. The CAS number is a numerical identifier for every single discovered chemical substance. This includes organic and inorganic compounds, minerals, and alloys, among others. One reason why the CAS number is so important is because it’s the standard for the chemical component. Many chemicals, like 2-butoxyethanol, have various names but the CAS number is consistent making it a good way to identify what exactly is in the product and associated hazards.
If the product is a mixture, all of the required information is the same as a substance, along with a few additional pieces. The chemical name and concentration of all the ingredients identified as health hazards must be listed. The concentration must also be specified exactly unless trade secret is involved, there is batch-to-batch variation, or an SDS is used for multiple mixtures that are similar. In these cases, a range is allowed.
When is it acceptable to not list an ingredient?
Ideally, all ingredients should be listed under Section 3. However, there are caveats to not listing ingredients. If an ingredient is classified as a hazardous substance under the GHS and its content surpasses the cut-off value, it must be disclosed. Depending on the toxicity of the hazard, the cut-off value is either 1% or .1% in most cases.
Non-hazardous contents are not required to be listed under Section 3. As a result, companies typically steer clear of listing these, as they do not want competitors obtaining their formula, tying back to trade secret.
Section 3 is arguably the most important portion of the SDS. All ingredients above the acceptable threshold must be listed. Hazards and possible side effects of the ingredients are known. Therefore, section 3 shows if the SDS is in fact valid. It is not unheard of for companies to deliberately leave out necessary hazardous symbols from Section 2 of the SDS. However, knowing side effects of ingredients in Section 3 can prove whether or not the SDS is accurate.Subscribe to the Chemtek blog and stay up to date on our Decoding SDS series!