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| w |
Threats
can be
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n |
Biological
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n |
Chemical
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n |
Radioactive
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n |
Physical
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| w |
In the
|
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n |
Natural
environment
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n |
Built
environment
|
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|
l |
Home
|
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l |
Workplace
|
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l |
Community
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| w |
They
can be spread by
|
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n |
Air:
indoor and out
|
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n |
Water:
drinking or not
|
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n |
Soil:
direct or indirect
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n |
Or a
combination
|
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| w |
And
caused by
|
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|
n |
Natural
events
|
|
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|
l |
Seasonal
|
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l |
Exceptional
|
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|
n |
Human
activity
|
|
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|
l |
Incidental
|
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|
l |
Deliberate
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