LIBERTY, August 31, 2017 - The chemical agents involved in the dangerous situation at the chemical plant in Crosby are called organic peroxides. Below is a discussion of the products.

An organic peroxide is any organic (carbon-containing) compound having two oxygen atoms joined together (-O-O-). This chemical group is called a "peroxy" group. Organic peroxides can be severe fire and explosion hazards. This question-and-answer document summarizes these and other hazards; another document provides information on how to work safely with organic peroxides. 

The plastics and rubber industries are the heaviest users of organic peroxides. Organic peroxides and mixtures containing an organic peroxide are used as accelerators, activators, catalysts, cross-linking agents, curing agents, hardeners, initiators and promoters. Organic peroxides and mixtures containing an organic peroxide are often referred to by these terms. However, using terms like accelerator, activator, etc. to mean "organic peroxide" can be misleading since they can also refer to materials that do not contain organic peroxides. This can cause confusion and a serious accident could result if these substances were mixed with organic peroxides. 

Organic peroxides are available as solids (usually fine powders), liquids or pastes. Some materials, such as water, odourless mineral spirits, and some phthalate esters do not react with organic peroxides and are often used to dilute them. The diluted mixtures or formulations are less likely to explode when exposed to heat or physical shock than the undiluted organic peroxide. Dilution makes the unstable peroxides safer to produce, handle, and use. We use the term "organic peroxide" to refer to both undiluted and diluted organic peroxides, unless otherwise specified. Check the supplier labels on chemical product containers. 

The Canadian WHMIS (Workplace Hazardous Materials Information System) 1988 classifies organic peroxides as oxidizing materials. WHMIS 1988 also classifies many other materials that are not organic peroxides as oxidizing materials. Other hazard symbols may also be present, depending on the particular material.
It is wise to treat any unknown material as very hazardous until it is positively identified.