Hexachlorobenzene

CAS number 118-74-1

Description

Hexachlorobenzene (HCB) is a white crystalline solid which is not very soluble in water. It is a bio accumulative, persistent, and toxic pollutant.

Uses

Hexachlorobenzene is currently formed as a byproduct during the manufacture of other chemicals (mainly solvents) and pesticides, and no longer produced for commercial use for itself (it was widely used as a pesticide until the late 1960s). Due to HCB’s persistence in the environment, it has been banned globally under the Stockholm Convention on persistent organic pollutants.

Although HCB production and use has ceased in many countries, the compound is still generated inadvertently, as a byproduct and/or impurity in the manufacture of various chlorinated compounds, and released into the environment. Hexachlorobenzene can be found in air, soil, and water after release from the manufacture, and wastage.

Why it can be problematic for human and animal health

Exposure to hexachlorobenzene is primarily through inhalation or ingestion but can also be dermal contact. The chemical is expected to be readily absorbed following oral exposure from contaminated water, food, soil or breast milk through the digestive tract. HCB can also be absorbed through the lungs to a lesser extent.

Hexachlorobenzene is shown in scientific literature as being associated with the following chronic health impacts:

Systemic damage – liver, thyroid, bone, skin, largely from ingesting of this chemical long term
Possible carcinogen, unknown in humans but shown in animal studies
One human study reported abnormal physical development in young children who ingested contaminated bread during a 4-year poisoning incident.
Immune, endocrine, developmental, and nervous systems have been impacted by HCB long term in animal studies - Reproductive, neurotoxic and developmental effects seen in animal studies of young animals exposed long term to this chemical.

No information is available on the acute (short-term) effects of hexachlorobenzene in humans.

Please note any adverse health effects that you may encounter in exposure to a chemical depend on several factors, including the amount to which you are exposed (dose), the way you are exposed, the duration of exposure, the form of the chemical and if you were exposed to any other chemicals.