1
Selenium Pollution
Around the World
Introduction
Selenium is a naturally occurring trace element that can be concentrated and released in the waste materials from certain mining, agricultural, petrochemical, and industrial manufacturing operations. Once
in the aquatic environment, it can rapidly bioaccumulate and reach
levels that are toxic to fish and wildlife. Selenium pollution is a worldwide phenomenon and is associated with a broad spectrum of human
activities ranging from the most basic agricultural practices to the most
high-tech industrial processes. Consequently, selenium contamination
of aquatic habitats can take place in urban, suburban, and rural settings alike-from mountains to plains, from deserts to rainforests, and
from the Arctic to the tropics. Few environmental contaminants have
the potential to affect aquatic resources on such a broad scale, and still
fewer exhibit the complex aquatic cycling pathways and range of toxic
effects that are characteristic of selenium. This places additional importance on the need for techniques to identify, diagnose, and respond
to aquatic selenium problems before they become widespread toxic
episodes. For many years, selenium has been a largely unrecognized
pollutant, particularly in developing nations, and it has been overshadowed by issues involving contaminants such as industrial chemicals, heavy metals, pesticides, and air pollutants among many others.
However, during the past decade, aquatic pollution surveillance and
monitoring programs have expanded markedly in terms of both the
areal extent of coverage and the range of substances measured. As a
result, selenium has emerged as an important environmental contaminant, and has gained the attention of natural resource managers and
water quality regulators around the world. This chapter presents an
overview of the wide variety of selenium sources that can lead to pollution of aquatic habitats and gives a sample of the many locations
where impacts to aquatic life have occurred.
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Selenium Pollution
Around the World
Introduction
Selenium is a naturally occurring trace element that can be concentrated and released in the waste materials from certain mining, agricultural, petrochemical, and industrial manufacturing operations. Once
in the aquatic environment, it can rapidly bioaccumulate and reach
levels that are toxic to fish and wildlife. Selenium pollution is a worldwide phenomenon and is associated with a broad spectrum of human
activities ranging from the most basic agricultural practices to the most
high-tech industrial processes. Consequently, selenium contamination
of aquatic habitats can take place in urban, suburban, and rural settings alike-from mountains to plains, from deserts to rainforests, and
from the Arctic to the tropics. Few environmental contaminants have
the potential to affect aquatic resources on such a broad scale, and still
fewer exhibit the complex aquatic cycling pathways and range of toxic
effects that are characteristic of selenium. This places additional importance on the need for techniques to identify, diagnose, and respond
to aquatic selenium problems before they become widespread toxic
episodes. For many years, selenium has been a largely unrecognized
pollutant, particularly in developing nations, and it has been overshadowed by issues involving contaminants such as industrial chemicals, heavy metals, pesticides, and air pollutants among many others.
However, during the past decade, aquatic pollution surveillance and
monitoring programs have expanded markedly in terms of both the
areal extent of coverage and the range of substances measured. As a
result, selenium has emerged as an important environmental contaminant, and has gained the attention of natural resource managers and
water quality regulators around the world. This chapter presents an
overview of the wide variety of selenium sources that can lead to pollution of aquatic habitats and gives a sample of the many locations
where impacts to aquatic life have occurred.
3