Polychlorinated biphenyl

Polychlorinated biphenyl (PCB) is a group of toxic organochloride compounds that are widely distributed in the environment and pose great hazard to human health.

Industrial products consisting of a mixture of chlorinated biphenyl congeners and isomers. These compounds are highly lipophilic and tend to accumulate in fat stores of animals. Many of these compounds are considered toxic and potential environmental pollutants.

PCB was used as a coolant for hydraulic and electrical equipment and was also used as a component of adhesives, plasticizers (chemicals that make plastic soft and flexible), inks, pesticide extenders, dyes and carbonless copy paper.

Although much of PCB production was curtailed in the 1970s owing to its toxic nature, it still poses a great environmental and personal health risk. This is not just because it is still used in closed systems such as electrical equipment like transformers and capacitors which can experience accidental leakages, but because PCB can be released into the soil, air and water from numerous sources including landfills containing PCB-containing products, incineration of refuse containing PCB-containing materials, and illegal disposal of PCB materials. PCB is classified as a persistent organic pollutant since it is generally resistant to breakdown by light, heat and air and is easily taken up by soil and water, bioconcentrated in animals and distributed throughout the food chain.

As such, dietary sources such as contaminated water and food are among the greatest sources of PCP exposure. While fish and waterfowl from PCB-contaminated water sources are among the primary dietary sources, there have also been reports of contamination of eggs, poultry and milk. For those who work with PCB-containing products and materials, inhalation and skin contact are likely to be the most significant routes of exposure.

Although there has not been enough research conducted involving humans to clearly establish PCB as a carcinogen (chemical capable of causing cancer), reflecting that there is sufficient evidence that it is carcinogenic to animals, the Environmental Protection Agency (EPA) classifies PCB as a probable human carcinogen.

In addition to its potential cancer-causing effects, toxicity symptoms of PCB intoxication in humans are varied and include acne, hyperpigmentation of the skin, liver damage, and elevated cholesterol levels. PBC has been shown to be capable of uncoupling a cellular energy-producing process known as oxidative phosphorylation with the result being a diminished supply of cellular energy available to power the cells, and therefore, the body.

As PCB is poorly metabolized, it is capable of accumulating in tissues, notably adipose (fat) tissue. PCB is of special concern to pregnant and lactating women as it is a teratogen (chemical capable of causing birth defects) that can cross the placenta and has also been found to be able to concentrate in breast milk.

PCB is of special concern to pregnant and lactating women as it is a teratogen (chemical capable of causing birth defects) that can cross the placenta and can become concentrated in breast milk.

PCB was used as a coolant for hydraulic and electrical equipment and was also used as a component of adhesives, plasticizers (chemicals that make plastic soft and flexible), inks, pesticide extenders, dyes and carbonless copy paper. Although much of PCB production was curtailed in the 1970s owing to its toxic nature, it still poses a great environmental and personal health risk. This is not just because it is still used in closed systems such as electrical equipment like transformers and capacitors which can experience accidental leakages, but because PCB can be released into the soil, air and water from numerous sources including: landfills containing PCB-containing products; incineration of refuse containing PCB-containing materials; and illegal disposal of PCB materials.

As such, dietary sources such as contaminated water and food are among the greatest sources of PCP exposure. While fish and waterfowl from PCB-contaminated water sources are among the primary dietary sources, there have also been reports of contamination of eggs, poultry and milk. For those who work with PCB-containing products and materials, inhalation and dermal contact are likely to be the most significant routes of exposure.

Probable human carcinogen

Although there has not been enough research conducted involving humans to clearly establish PCB as a carcinogen (chemical capable of causing cancer), reflecting that there is sufficient evidence that it is carcinogenic to animals, the Environmental Protection Agency (EPA) classifies PCB as a probable human carcinogen. In addition to its potential cancer causing effects, toxicity symptoms of PCB intoxication in humans are varied and includes acne, hyperpigmentation of the skin, liver damage, and elevated cholesterol levels. PBC has been shown to be capable of uncoupling a cellular energy-producing process known as phosphorylation with the result being a diminished supply of cellular energy available to power the cells, and therefore, the body. As PCB is poorly metabolized, it is capable of accumulating in tissues, notably adipose (fat) tissue.