
Polychlorinated biphenyls (PCBs) are a family of human-created organic chemicals known as chlorinated hydrocarbons. They have been recorded in high concentrations in water bodies since the 1960s due to improper disposal, accidental spillage, and discharge of PCB-containing materials. PCBs have devastating eco-toxicological effects on humans, animals, and ecosystems.
Characteristics | Values |
---|---|
Definition | Polychlorinated biphenyls (PCBs) are a broad family of human-created organic chemicals known as chlorinated hydrocarbons. |
Manufacturing | PCBs were manufactured domestically from 1929 until manufacturing was banned in 1979. An estimated 1.5 billion pounds of PCBs were made for things such as microscope oils, electrical insulators, capacitors, and electric appliances. |
Toxicity | PCBs have a range of toxicity and vary in consistency from thin, light-colored liquids to yellow or black waxy solids. |
Pollution | PCBs have been recorded in water bodies resulting in global pollution of marine environments from nearby industrial activities since the 1960s. |
Dominant Congeners | Lower chlorinated biphenyls are the dominant congeners in the middle reaches and higher chlorinated biphenyls are the dominant congeners in the lower reaches. Tetra-CBs are the dominant congeners in SPM. |
Transport | The transport of PCB18, PCB28, PCB47, and PCB118 in sediment and water did not reach equilibrium yet. |
Partition Coefficient | The SPM-water partition coefficient (Kd) reflects whether the adsorption of chemical substances favors the SPM than the aqueous environment. |
Factors affecting Kd value | Organic matter content, temperature, mineral composition, and median particle size are all important factors affecting Kd value. |
What You'll Learn
Polychlorinated biphenyls (PCBs) are human-made organic chemicals
PCBs are toxic and have a range of toxicity, varying in consistency from thin, light-colored liquids to yellow or black waxy solids. They are harmful to aquatic animals and have devastating eco-toxicological effects on humans, animals, and ecosystems.
PCBs are persistent organic pollutants and have not reached equilibrium in their exchange between sediment and water. This means that they can transport between media and are present in high concentrations in water bodies as a result of improper disposal, accidental spillage, and discharge of PCB-containing materials or effluents.
PCBs are dominant congeners in both water and sediment, with lower chlorinated biphenyls being dominant in the middle reaches and higher chlorinated biphenyls being dominant in the lower reaches. The transport of PCBs in sediment and water did not reach equilibrium, and the fugacity fraction is commonly used to demonstrate the equilibrium state.
PCBs are harmful to the health of aquatic animals and have devastating eco-toxicological effects on humans, animals, and ecosystems. They are toxic to marine environments and have been recorded in high concentrations in water bodies since the 1960s due to industrial activities.
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PCBs are toxic to humans, animals, and ecosystems
Polychlorinated biphenyls (PCBs) are a family of human-made organic chemicals known as chlorinated hydrocarbons. They were manufactured from 1929 until 1979 and are harmful to human and environmental health. PCBs have a range of toxicity and vary in consistency from thin, light-colored liquids to yellow or black waxy solids.
Improper disposal, accidental spillage, and discharge of PCB-containing materials or effluents associated with their long-range atmospheric transport have resulted in marine pollution as well as several devastating eco-toxicological effects on humans, animals, and ecosystems.
PCBs are persistent organic pollutants and have not reached equilibrium in their exchange between sediment and water. The fugacity fraction is commonly used to demonstrate the equilibrium state because the two directions of the equilibrium line (ff = 0.50) represent the same level of the deviation from the balanced state. The value of the fugacity fraction (ff) can be used as one of the indicators to evaluate the transport of PCBs between two phases.
PCBs were banned in the U.S. in 1979 because these chemicals harm human and environmental health. From the 1920s until their ban, an estimated 1.5 billion pounds of PCBs were made for things such as microscope oils, electrical insulators, capacitors, and electric appliances such as television sets or refrigerators.
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PCBs are persistent organic pollutants
PCBs, or polychlorinated biphenyls, are a family of human-created organic chemicals known as chlorinated hydrocarbons. They were manufactured from 1929 until 1979, when manufacturing was banned in the U.S. due to harm to human and environmental health. PCBs have a range of toxicity and vary in consistency from thin, light-colored liquids to yellow or black waxy solids.
The transport of PCBs among multi-matrix compartments is evaluated by selecting predominant PCB congeners in water, sediment, and SPM. The SPM-water partition coefficient (Kd) reflects whether the adsorption of chemical substances favors the SPM over the aqueous environment. The logKd values of PCB18, 28, 47, and 118 were calculated to be 3.50-4.16, 3.20-4.28, 3.17-4.90, and 3.03-4.07, respectively. These values indicate that the four PCBs have similar Kd, and factors such as organic matter content, temperature, mineral composition, and median particle size affect the Kd value.
PCBs have devastating eco-toxicological effects on humans, animals, and ecosystems. High concentrations of low or high-chlorinated PCBs (dioxin and non-dioxin-like congeners) have been recorded in water bodies resulting in global pollution of marine environments from nearby industrial activities since the 1960s. This pollution presents a risk for aquatic animals' health and has improper disposal, accidental spillage, and discharge of PCB-containing materials or effluents associated with their long-range atmospheric transport have resulted in marine pollution as well as several devastating eco-toxicological effects on humans, animals, and ecosystems.
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High concentrations of PCBs are recorded in water bodies
High concentrations of low or high-chlorinated PCBs (dioxin and non-dioxin-like congeners) have been recorded in water bodies resulting in global pollution of marine environments from nearby industrial activities since the 1960s. This pollution presents a risk for aquatic animals’ health both pelagic and benthic as well as invertebrates (plankton, salmons, fishes, shellfishes, farmed fishes, swordfishes, sea birds, sea turtles, sea eagles frogs, dolphins, sharks, whales, seals, and other marine animals). Improper disposal, accidental spillage, and discharge of PCB-containing materials or effluents associated with their long-range atmospheric transport have resulted in marine pollution as well as several devastating eco-toxicological effects on humans, animals, and ecosystems.
PCB contamination is high in the Housatonic River and New Bedford Harbor in Massachusetts. According to the EPA, PCBs belong to a broad family of human-created organic chemicals known as chlorinated hydrocarbons. PCBs were manufactured domestically from 1929 until manufacturing was banned in 1979. They have a range of toxicity and vary in consistency from thin, light-colored liquids to yellow or black waxy solids.
The transport of PCB18, PCB28, PCB47, and PCB118 in sediment and water did not reach equilibrium yet. Thus, just like organochlorine pesticides (OCPs), known as persistent organic pollutants, PCBs have not reached equilibrium in their exchange between sediment and water either. The fugacity fraction is commonly used to demonstrate the equilibrium state because the two directions of the equilibrium line (ff = 0.50) represent the same level of the deviation from the balanced state. The value of the fugacity fraction (ff) can be used as one of the indicators to evaluate the transport of PCBs between two phases.
Two representative types of PCBs (ind-PCBs and co-PCBs) were analyzed as the indicators of environmental pollution and toxicity. The proportion of seven ind-PCBs to ΣPCBs varied between 1.54 and 64.4%. The congener profile of the ind-PCBs is dominated by the tri-CB PCB28 and the penta-CB PCB118, and other congeners contribute much less. Besides, the concentration of co-PCBs is significantly lower in water than in SPM, likely due to the low polarity, poor water solubility, and low content of co-PCBs in water.
Multiple parameters are used to represent the transport of pollutants between media. In this study, predominant PCB congeners in water, sediment, and SPM (including PCB18, 28, 47, and 118) were selected to evaluate the transport of PCBs among multi-matrix compartments. The SPM–water partition coefficient (Kd) reflects whether the adsorption of chemical substances favors the SPM than the aqueous environment. The logKd values of PCB18, 28, 47, and 118 were calculated from Eq. (1) to be 3.50–4.16, 3.20–4.28, 3.17–4.90, and 3.03–4.07, respectively. Hence, the four PCBs have similar Kd. Organic matter content, temperature, mineral composition, and median particle size are all important factors affecting Kd value.
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PCBs are banned in the U.S
Polychlorinated biphenyls (PCBs) are a family of human-made organic chemicals known as chlorinated hydrocarbons. They were manufactured from 1929 until 1979 and were used in a variety of products, including microscope oils, electrical insulators, capacitors, and electric appliances.
PCBs have a range of toxicity and can vary in consistency from thin, light-colored liquids to yellow or black waxy solids. They were banned in the U.S. in 1979 because they were found to harm human and environmental health.
The improper disposal, accidental spillage, and discharge of PCB-containing materials have resulted in marine pollution and devastating eco-toxicological effects on humans, animals, and ecosystems. High concentrations of low or high-chlorinated PCBs have been recorded in water bodies, resulting in global pollution of marine environments from nearby industrial activities since the 1960s.
The transport of PCBs in sediment and water has not yet reached equilibrium, and they are known as persistent organic pollutants. The fugacity fraction is commonly used to demonstrate the equilibrium state because the two directions of the equilibrium line (ff = 0.50) represent the same level of deviation from the balanced state.
The proportion of seven ind-PCBs to ΣPCBs varied between 1.54 and 64.4%. The congener profile of the ind-PCBs is dominated by the tri-CB PCB28 and the penta-CB PCB118, and other congeners contribute much less. The concentration of co-PCBs is significantly lower in water than in SPM, likely due to the low polarity, poor water solubility, and low content of co-PCBs in water.
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Frequently asked questions
PCBs, or polychlorinated biphenyls, are a broad family of human-created organic chemicals known as chlorinated hydrocarbons.
PCBs have been recorded in water bodies resulting in global pollution of marine environments from nearby industrial activities since the 1960s.
PCB pollution has devastating eco-toxicological effects on humans, animals, and ecosystems.
PCBs were banned in the U.S. in 1979 because these chemicals harm human and environmental health.