Chemistry Reference
In-Depth Information
7.1.9 o
ccupAtionAl
s
Afety
And
H
eAltH
A
dministrAtion
(osHA)
OSHA has developed Permissible Exposure Limits (PELs) for 20 metals and metal
compounds (
Table 7.1
). PELs are regulatory limits on the amount or concentration
of a substance in the air to protect workers against the health effects of exposure
to hazardous substances (OSHA 2006). OSHA PELs are based on an 8-hour time-
weighted average (TWA) exposure.
7.1.10 u
nited
n
Ations
e
nvironmentAl
p
roGrAm
(unep)
The UNEP provides leadership and encourages partnership in caring for the envi-
ronment by inspiring, informing, and enabling nations and peoples to improve their
quality of life without compromising that of future generations (
http://www.unep.org/
Documents.Multilingual/Default.asp?DocumentID
= 43). The UNEP has developed
6 Health and Safety Guides (HSG) (UNEP 1999), 16 Environmental Health Criteria
(EHC) Monographs (UNEP 2006), Concise International Chemical Assessment
Documents (CICADS) (UNEP 2009a), 8 Poisons Information Monographs (PIMs)
(UNEP 2009b), and 27 International Chemical Safety Cards (ICSCs) (UNEP 2009c)
7.1.11 us e
nvironmentAl
p
rotection
A
Gency
(us epA)
The US EPA implemented four laws that are used to set regulatory limits for met-
als, including the Clean Air Act, the Clean Water Act, the Emergency Planning and
Community Right-to-Know Act, and the Comprehensive Environmental Response,
Compensation, and Liability Act. These laws and the metals for which they set regu-
latory limits are briefly discussed below.
7.1.11.1 Clean Air Act
The US EPA Clean Air Act Amendments of 1990 list antimony compounds, arse-
nic compounds (inorganic including arsine), beryllium compounds, cadmium
compounds, chromium compounds, cobalt compounds, lead compounds, man-
ganese compounds, mercury compounds, and nickel compounds as Hazardous
Air Pollutants (HAPs) (US EPA 2008a). The
compound
designation is defined to
include any unique chemical substance that contains the specified metal as part of
that chemical's structure (US EPA 2008a). The Clean Air Act requires the EPA to
set National Ambient Air Quality Standards (NAAQS; 40 C.F.R. Part 50) for pol-
lutants considered harmful to public health and the environment (US EPA 2008).
Primary standards set limits to protect public health, including the health of espe-
cially sensitive populations (such as asthmatics, children, and the elderly), while sec-
ondary standards set limits to protect public welfare, including protection against
decreased visibility, and damage to animals, crops, vegetation, and buildings. Of
the six principal pollutants for which NAAQS have been set, lead is the only metal.
The primary and secondary standards for lead are the same,
viz
., 0.15 µg/m
3
as a
