This includes several factors such as the number of toxicants present in the
environment, bioaccumulation in the food chain, the bioavailability of such toxicants
after absorption process metabolic changes that happen within humans. All these
factors totally combine to form the bioaccumulation level in human tissues. Notably,
once the toxicants get released into the environment, it directly attaches itself to the
food sources, thereby entering the food chain of humans, an important mechanism of
bioaccumulation in terrestrial ecosystems.
14.6.2 Aquatic Ecosystem
According to the USEPA, even a low concentration of dioxins and furans is highly
lethal to aquatic organisms. It is estimated that the aquatic life accumulates such
toxic elements in their body near the vicinity of dioxin- and furan-related industries.
Edible parts of certain fish varieties such as catfish, yellow perches and suckerfish
from Saginaw Bay, Michigan, United States, were estimated for the accumulation of
dioxins and furans which was around 4.0–695 ng/Kg. It was reported that a certain
type of fish variety called “bottom feeder fish” accumulated more dioxins and furans
because it directly feeds on the adsorbed contaminants in water. Dioxins and furans
were also targeted several species of crabs. A mean concentration level of 990 pg/g
was observed in hepato-pancreas of crabs in Sweden which was due to the effluent
discharge from the paper industry. One of the major congeners responsible for
contamination of the aquatic ecosystem is later found to be 2,3,7,8– PCDD/PCDF.
The acute and chronic levels of concentration are estimated to be 0.01 μg/L and
0.001 μg/L, respectively. Thompson et al. (1992) reported the elevated levels of
dioxins and furans in shellfish and fish varieties in Australia. The overall predicted
bioaccumulation factor in aquatic life is estimated to be around 3000–900,000, but
the measured value was around 390–13,000. Assefa et al. (2019) investigated about
the aquatic contamination of dioxins/furans in several species of Atlantic herring
fishes using statistical modelling approach and concluded that the thermal sources
were the biggest toxicants in herring fishes of the Baltic Sea. Biomagnification of
dioxins/furans in lipid content of aquatic fish in China was found to have positive
significant correlation on adverse health effects in humans who consume high-fatcontent fish varieties (Zhou et al. 2019). Recently, Bartalini et al. (2019) reported
inceptive immunosuppression of all sperm whales in the Mediterranean Sea that
surpassed the threshold of 210 pg WHO-TEQ/g l.w.
14.7 Health Effects in Humans
High exposure to dioxin/furan compounds can result in various diseases of several
effects depending on many factors. These factors include dosage of exposure, sex of
the individual, duration of exposure and method of contact with the contaminants.
Dioxins/furans enter into the human system by food chain through dairy products
such as milk, meat, fish and eggs and are accumulated in the system for a very long
14 Biological Implications of Dioxins/Furans Bioaccumulation in Ecosystems
407
environment, bioaccumulation in the food chain, the bioavailability of such toxicants
after absorption process metabolic changes that happen within humans. All these
factors totally combine to form the bioaccumulation level in human tissues. Notably,
once the toxicants get released into the environment, it directly attaches itself to the
food sources, thereby entering the food chain of humans, an important mechanism of
bioaccumulation in terrestrial ecosystems.
14.6.2 Aquatic Ecosystem
According to the USEPA, even a low concentration of dioxins and furans is highly
lethal to aquatic organisms. It is estimated that the aquatic life accumulates such
toxic elements in their body near the vicinity of dioxin- and furan-related industries.
Edible parts of certain fish varieties such as catfish, yellow perches and suckerfish
from Saginaw Bay, Michigan, United States, were estimated for the accumulation of
dioxins and furans which was around 4.0–695 ng/Kg. It was reported that a certain
type of fish variety called “bottom feeder fish” accumulated more dioxins and furans
because it directly feeds on the adsorbed contaminants in water. Dioxins and furans
were also targeted several species of crabs. A mean concentration level of 990 pg/g
was observed in hepato-pancreas of crabs in Sweden which was due to the effluent
discharge from the paper industry. One of the major congeners responsible for
contamination of the aquatic ecosystem is later found to be 2,3,7,8– PCDD/PCDF.
The acute and chronic levels of concentration are estimated to be 0.01 μg/L and
0.001 μg/L, respectively. Thompson et al. (1992) reported the elevated levels of
dioxins and furans in shellfish and fish varieties in Australia. The overall predicted
bioaccumulation factor in aquatic life is estimated to be around 3000–900,000, but
the measured value was around 390–13,000. Assefa et al. (2019) investigated about
the aquatic contamination of dioxins/furans in several species of Atlantic herring
fishes using statistical modelling approach and concluded that the thermal sources
were the biggest toxicants in herring fishes of the Baltic Sea. Biomagnification of
dioxins/furans in lipid content of aquatic fish in China was found to have positive
significant correlation on adverse health effects in humans who consume high-fatcontent fish varieties (Zhou et al. 2019). Recently, Bartalini et al. (2019) reported
inceptive immunosuppression of all sperm whales in the Mediterranean Sea that
surpassed the threshold of 210 pg WHO-TEQ/g l.w.
14.7 Health Effects in Humans
High exposure to dioxin/furan compounds can result in various diseases of several
effects depending on many factors. These factors include dosage of exposure, sex of
the individual, duration of exposure and method of contact with the contaminants.
Dioxins/furans enter into the human system by food chain through dairy products
such as milk, meat, fish and eggs and are accumulated in the system for a very long
14 Biological Implications of Dioxins/Furans Bioaccumulation in Ecosystems
407