weathering of cadmium-containing rocks, volcanic activity, forest fires, sea spray,
and mobilization of cadmium previously deposited in soils, sediments, landfills, etc.
It is estimated that 15,000 metric tons of cadmium is transported to oceans through
rivers due to weathering and erosion of rocks (WHO 1992; OECD 1994).
3.2 Anthropogenic Sources
The largest source of anthropogenic atmospheric cadmium emissions is ferrous and
nonferrous metal production (smelting and refining of zinc ores) followed by waste
incineration, production of nickel-cadmium batteries, fossil fuel combustion, iron
and steel plants, electroplating wastes, fertilizer and fungicide application, and
generation of dust by industrial processes such as cement manufacturing (Kazantzis
1987; Huff 1999; ATSDR 2012). From these human activities, an estimated
4000–13,000 tons of cadmium is released into the environment every year (EPA
2004). Cadmium present in soil from industrial emissions or other sources is
selectively taken up by edible plants, resulting in levels much higher than those in
the surrounding soils. Cadmium has also been shown to bio-concentrate in water
plants and in fish. Of special concern are Mollusca and Crustacea; cadmium levels in
crab may be as high as 30–50 parts per million (Schwartz and Reis 2000).
Different ways by which people are exposed to cadmium are:
• Non-smoking population is exposed to cadmium primarily via ingestion of food
(approx. 90%) and, to a lesser extent, via inhalation of ambient air, ingestion of
drinking water, contaminated soil, or dust (Fig. 15.2).
Cigarettes
smoking
Ingestion of
cadmium containing
food and water
Consuming food and
beverages served in
glassware and tableware
decorated with cadmium
based pigments
Cadmium
exposure in
human beings
Breathing
cadmium
containing air
Mouthing or
swallowing
cadmium
containing items
such as inexpensive
children jewelry
Occupational
settings involving
Cd production and
utilization
Fig. 15.2 Different ways of cadmium exposure
362
S. Saini and G. Dhania
and mobilization of cadmium previously deposited in soils, sediments, landfills, etc.
It is estimated that 15,000 metric tons of cadmium is transported to oceans through
rivers due to weathering and erosion of rocks (WHO 1992; OECD 1994).
3.2 Anthropogenic Sources
The largest source of anthropogenic atmospheric cadmium emissions is ferrous and
nonferrous metal production (smelting and refining of zinc ores) followed by waste
incineration, production of nickel-cadmium batteries, fossil fuel combustion, iron
and steel plants, electroplating wastes, fertilizer and fungicide application, and
generation of dust by industrial processes such as cement manufacturing (Kazantzis
1987; Huff 1999; ATSDR 2012). From these human activities, an estimated
4000–13,000 tons of cadmium is released into the environment every year (EPA
2004). Cadmium present in soil from industrial emissions or other sources is
selectively taken up by edible plants, resulting in levels much higher than those in
the surrounding soils. Cadmium has also been shown to bio-concentrate in water
plants and in fish. Of special concern are Mollusca and Crustacea; cadmium levels in
crab may be as high as 30–50 parts per million (Schwartz and Reis 2000).
Different ways by which people are exposed to cadmium are:
• Non-smoking population is exposed to cadmium primarily via ingestion of food
(approx. 90%) and, to a lesser extent, via inhalation of ambient air, ingestion of
drinking water, contaminated soil, or dust (Fig. 15.2).
Cigarettes
smoking
Ingestion of
cadmium containing
food and water
Consuming food and
beverages served in
glassware and tableware
decorated with cadmium
based pigments
Cadmium
exposure in
human beings
Breathing
cadmium
containing air
Mouthing or
swallowing
cadmium
containing items
such as inexpensive
children jewelry
Occupational
settings involving
Cd production and
utilization
Fig. 15.2 Different ways of cadmium exposure
362
S. Saini and G. Dhania