14.6.1 Terrestrial Ecosystem
Out of all the sources, food exposure becomes the predominant source of toxic
elements to humans in the terrestrial ecosystem. The main reason behind this
scenario is that the concentration of abundant nutrients in each level of the food
pyramid is different. Since both dioxins and furans are highly lipid-soluble, stable
and less biodegradable, they reach the topmost part of the pyramid instantly. In
terrestrial ecosystems, one of the main concerns is dairy products. Dioxins and
furans emitted by incinerators, fly-ash machines, cement kilns, etc. are found to be
less than 0.1–100 ng/m
3 . Particles of this size are easily deposited on the plants,
grass, weed and even soil because of certain climatic conditions such as precipitation
and atmospheric currents. In vitro bioaccessibility of dioxins and furans from soil
matrix within the human gastrointestinal tract ranged from 34.3% to 62.1% (Roberts
et al. 2019). Cockerham and Young (1983) reported that the beach mice
(Peromyscus polionotus) showed levels of 540–1300 ng/Kg TCDD in liver tissues.
Young et al. (1976) studied the contamination levels in a reptile, Cnemidophorus
sexlineatus, and estimated the levels of dioxins and furans to be around 360 ng/Kg in
the visceral mass and 370 ng/Kg in the trunk of the reptile. Hryhorczuk et al. (1981)
studied the contamination of dioxins and furans in grazing horse cattle and found
levels over 165 ng/Kg in fat tissues and 57 ng/Kg in liver tissues. Cow grazing in an
outside environment is directly exposed to such toxic chemicals contaminating their
feed such as grass and hay. An amount of 1–50 pg TEQ/g (level of contamination) of
dioxins/furans is directly ingested into the system of a higher organism. After
ingestion, the gastrointestinal absorption of dioxins and furans by the animal takes
place, thus resulting in a very low absorption rate. Generally, half-life times
of dioxins and furans in cows are very low because lactation is the only route of
excretion; moreover, the distribution of dioxins and furans throughout the body of
cows is very high since it directly deposits on the adipose tissues of cows. PiskorskaPliszczynska et al. (2017) reported that sugar beet pellets are the main source for
dioxin and furans contamination in cow’s milk. Dioxin and furan contamination has
the ability to increase the chromosomal abnormalities and fragility in sheep
(Perucatti et al. 2006), cow (Di Meo et al. 2010) and buffalo (Genualdo et al.
2012). Meat outlets in France revealed a detectable range of dioxins and furans to
be around <1 pg TEQ/g fat. Similarly, in Austria, the dioxin and furan level goes up
to 69 pg TEQ/g fat in cow’s milk where the location is very close to a copper smelter.
When compared with the bovine fat, the concentration of dioxins and furans in
human fat is nearly 10 times higher. In vivo studies of dioxin and furan contamination on buffaloes reported 1,2,3,7,8-PCDD, 2,3,4,7,8-PCDF, 2,3,7,8-TCDD and
1,2,3,6,7,8-HCDD as the major contributors of TEF (Chirollo et al. 2018).
Schuhmacher et al. (2019) compared the dioxin TEQs of NATO and WHO with
that of the human breast milk TEQ which was significantly independent and moving
in a decreased trend. Breast milk of humans has been observed to contain nearly
10–30 pg TEQ/g. From 2008 to 2011, dioxin and furan concentration in human
breast milk was found to decrease in Canada (Rawn et al. 2017). Further, dioxin and
furan contamination in human breast milk is higher in Europe than in North
14 Biological Implications of Dioxins/Furans Bioaccumulation in Ecosystems
405
Out of all the sources, food exposure becomes the predominant source of toxic
elements to humans in the terrestrial ecosystem. The main reason behind this
scenario is that the concentration of abundant nutrients in each level of the food
pyramid is different. Since both dioxins and furans are highly lipid-soluble, stable
and less biodegradable, they reach the topmost part of the pyramid instantly. In
terrestrial ecosystems, one of the main concerns is dairy products. Dioxins and
furans emitted by incinerators, fly-ash machines, cement kilns, etc. are found to be
less than 0.1–100 ng/m
3 . Particles of this size are easily deposited on the plants,
grass, weed and even soil because of certain climatic conditions such as precipitation
and atmospheric currents. In vitro bioaccessibility of dioxins and furans from soil
matrix within the human gastrointestinal tract ranged from 34.3% to 62.1% (Roberts
et al. 2019). Cockerham and Young (1983) reported that the beach mice
(Peromyscus polionotus) showed levels of 540–1300 ng/Kg TCDD in liver tissues.
Young et al. (1976) studied the contamination levels in a reptile, Cnemidophorus
sexlineatus, and estimated the levels of dioxins and furans to be around 360 ng/Kg in
the visceral mass and 370 ng/Kg in the trunk of the reptile. Hryhorczuk et al. (1981)
studied the contamination of dioxins and furans in grazing horse cattle and found
levels over 165 ng/Kg in fat tissues and 57 ng/Kg in liver tissues. Cow grazing in an
outside environment is directly exposed to such toxic chemicals contaminating their
feed such as grass and hay. An amount of 1–50 pg TEQ/g (level of contamination) of
dioxins/furans is directly ingested into the system of a higher organism. After
ingestion, the gastrointestinal absorption of dioxins and furans by the animal takes
place, thus resulting in a very low absorption rate. Generally, half-life times
of dioxins and furans in cows are very low because lactation is the only route of
excretion; moreover, the distribution of dioxins and furans throughout the body of
cows is very high since it directly deposits on the adipose tissues of cows. PiskorskaPliszczynska et al. (2017) reported that sugar beet pellets are the main source for
dioxin and furans contamination in cow’s milk. Dioxin and furan contamination has
the ability to increase the chromosomal abnormalities and fragility in sheep
(Perucatti et al. 2006), cow (Di Meo et al. 2010) and buffalo (Genualdo et al.
2012). Meat outlets in France revealed a detectable range of dioxins and furans to
be around <1 pg TEQ/g fat. Similarly, in Austria, the dioxin and furan level goes up
to 69 pg TEQ/g fat in cow’s milk where the location is very close to a copper smelter.
When compared with the bovine fat, the concentration of dioxins and furans in
human fat is nearly 10 times higher. In vivo studies of dioxin and furan contamination on buffaloes reported 1,2,3,7,8-PCDD, 2,3,4,7,8-PCDF, 2,3,7,8-TCDD and
1,2,3,6,7,8-HCDD as the major contributors of TEF (Chirollo et al. 2018).
Schuhmacher et al. (2019) compared the dioxin TEQs of NATO and WHO with
that of the human breast milk TEQ which was significantly independent and moving
in a decreased trend. Breast milk of humans has been observed to contain nearly
10–30 pg TEQ/g. From 2008 to 2011, dioxin and furan concentration in human
breast milk was found to decrease in Canada (Rawn et al. 2017). Further, dioxin and
furan contamination in human breast milk is higher in Europe than in North
14 Biological Implications of Dioxins/Furans Bioaccumulation in Ecosystems
405