To better understand how toxic TCDD is, one needs to understand how it and other toxins are measured. In toxicology, the median lethal dose is identified as LD₅₀ (abbreviation for “lethal dose, 50%”).

In the fire restoration industry today, very little attention is given to the toxicity of volatile organic compounds (VOC’s), heavy metals, or the composition of particulate matter and smoke residues.

On April 15, 2019, fire broke out beneath the roof of the Notre-Dame de Paris Cathedral. Over 400 firefighters fought the blaze, which consumed approximately two thirds of the roof structure, including the 300-foot wooden spire. 

During a structure fire, toxic smoke, volatile organic compounds (VOCs), and particulate matter are generated from the vast array of building materials, contents, and household products that combust. These chemicals mix and interact with each other to create a vast array of carcinogens, poisonous gasses, acids, and other toxins that can cause acute and chronic illnesses, cancer, and even death.

After a structure fire, restoration contractors are often on scene within hours to perform emergency services.  This usually begins with boarding up windows and doors and covering holes in the roof cut by the fire department.