Disposal or Other Releases of TRI Chemicals
Disposal or other releases of chemicals into the environment occur
through a range of practices. They may take place at a facility as
an on-site disposal or other release to air, water, land, or an
underground injection well; or they may take place at an off-site
location when a facility transfers waste that contains TRI chemicals
as an off-site disposal or other release.
Evaluating disposal and other releases can help the public identify
potential concerns and gain a better understanding of possible
hazards related to TRI chemicals. It can also help identify priorities
and opportunities for government to work with industry to reduce
toxic chemical disposal or other releases and potential associated
risks.
Figure 4 shows that disposal or other releases of TRI chemicals
have generally decreased in the long-term: down 8% from 2003 to 2011. This downward
trend over the nine-year period was driven by reductions in on-site air emissions. From
2010 to 2011, however, there was an 8% increase in disposal or other releases, mostly
due to increases from the metal mining sector. The number of facilities reporting to TRI
remained relatively steady from 2010 to 2011, decreasing by 1%.
Figure 4. On- and Off-site Disposal or Other Releases, 2003-2011
5,000
4,000
= 3.000
CL
O
oo
C
~ 2,000
Total Off-site Disposal or Other Releases
On-site Land Disposal or Other Releases
I On-site Underground Injection
I On-site Surface Water Discharges
I On-site Air Releases
- Number of Facilities
lllllllll
2003 2004 2005 2006 2007 2008 2009 2010 2011
Year
20,000
15,000
3
cr
n>
5,000
Many factors can affect trends in disposal or other releases, including changes in
production, changes in management practices at facilities, changes in the composition in
raw materials used at facilities and installation of control technologies. However, in the
last few years increases in disposal or other releases have been driven mainly by
increases in land disposal at metal mines, which typically handle large volumes of
material. In this sector, even a small change in the chemical composition of the ore being
mined can lead to big changes in the amount of toxic chemicals reported nationally. In
recent years mines have cited increased production, waste rock disposal, and changes in
the composition of waste rock as reasons for increased land disposal of TRI chemicals.
6 Disposal or Other Releases of TRI Chemicals
2011 TRI National Analysis Overview
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Decreases over time in disposal or other releases have been driven mainly by declining
air releases, down 788 million pounds since 2003. Most of this decline was due to
decreases in hazardous air pollutant (HAP) emissions, such as hydrochloric acid, at
electric utilities. Likely reasons for the decreases include a shift from coal to other fuel
sources and installation of control technologies at coal-fired power plants.
Newly Reported Chemicals for 2011
2011 is the first year that facilities are required to report on 16 new chemicals that
have been classified as "reasonably anticipated to be a human carcinogen" by the
National Toxicology Program (NTP). Twelve
of these chemicals are individually-listed
and four were added to the existing
polycyclic aromatic compounds (PACs)
category.
Reports were received for nine of the 12
new individually-listed chemicals.
Tetrafluoroethylene comprised more than
50% of the total on-site and off-site
disposal and other releases, while the
most reports were received for isoprene.
The majority of releases were on-site
releases to air, as shown in Figure 5.
To learn more about these new chemicals added to TRI, go to www.epa.gov/tri/
lawsandregs/nto chemicals/final.html.
Some of the chemicals on the TRI chemical list have been designated as persistent,
bioaccumulative, and toxic (PBT) chemicals. PBT chemicals are of particular concern not
only because they are toxic, but also because they remain in the environment for long
periods of time, and they tend to build up, or bioaccumulate, in the tissue of organisms.
Here we look more closely at several PBT chemicals: lead and lead compounds; mercury
and mercury compounds; dioxin and dioxin-like compounds; and PCBs.
Lead and lead compounds accounted for the vast majority (98%) of the disposal or other
releases of PBT chemicals in 2011 and tend to drive trends over time for PBTs. The
quantities of lead and lead compounds disposed of or otherwise released rose and fell
between 2003 and 2011, with a substantial increase occurring from 2009 to 2011
(102%); trends were primarily driven by changes in on-site land disposal or other releases
from the metal mining sector.
Mercury, another PBT chemical of concern, has traditionally been used to make products
such as thermometers, switches, and some light bulbs. It is also found in many naturally
occurring ores and minerals, including coal. The overall trend in disposal or other
releases of mercury and mercury compounds is driven by metal mines, which accounted
Figure 5. Individually Listed Carcinogens
added to TRI for RY2011
TRI Disposal or Other Releases, 2011
937 thousand pounds
On-site
Surface Water
Discharges
On-site 9%
7 Disposal or Other Releases of TRI Chemicals
2011 TRI National Analysis Overview
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for 97% of on-site land disposal of mercury in 2011 In the United States, coal-burning
power plants are the largest source of mercury emissions to the air. Electric utilities,
which include coal- and oil-fired power plants, accounted for 65% of the mercury and
mercury compounds air emissions reported to TRI in 2011. Since 2003, air releases of
mercury and mercury compounds decreased by 36%, including a 10% decrease from
2010 to 2011, as shown in Figure 6. Likely reasons for the decreases include a shift
from coal to other fuel sources, and installation of control technologies at coal-fired
power plants.
Figure 6. Air Releases, 2003-2011:
Mercury and Mercury Compounds
160
2003 2004 2005 2006 2007 2008 2009 2010 2011
Year
Dioxin and dioxin-like compounds (dioxins) are not only PBTs but are also characterized
by EPA as probable human carcinogens. Dioxins are the unintentional by-products of
most forms of combustion and several industrial chemical processes. Figure 7 shows
the amount of dioxins disposed of or otherwise released in total grams. Disposal or
other releases of dioxins increased 35% from 2010 to 2011 but decreased by 60%
from 2003 to 2011. In 2011, most (80%) of this quantity was disposed of in on- and
off-site RCRA subtitle C or other landfills. The figure also shows increased off-site
transfers to disposal from 2010 to 2011, which are primarily due to transfers from one
chemical manufacturing facility.
TRI requires facilities to report on 17 types of dioxin and dioxin-like compounds (or
congeners). These congeners have a wide range of toxicities. The mix of dioxins from
one source can have a very different level of toxicity than the same total amount, but
different mix, from another source. These varying toxicities can be taken into account
with Toxic Equivalency Factors (TEFs), which are based on each congener's toxicity
data. The total grams of each congener can be multiplied by its TEF to obtain a toxicity
weight. The results can then be summed for a total of grams in toxicity equivalents
(TEQ).
8 Disposal or Other Releases of TRI Chemicals
2011 TRI National Analysis Overview
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Figure 7. Disposal or Other Releases, 2003-2011:
Dioxin and Dioxin-like Compounds
160,000
140,000
120,000
100,000
E
TJ
k_
80,000
60,000
40,000
20,000
I
I
i
i
2003 2004 2005 2006
2007
Year
Total Off-site Disposal or Other Releases
On-site Land Disposal or Other Releases
I On-site Underground Injection
I On-site Surface Water Discharges
I On-site Air Releases
I
2008 2009 2010 2011
Analyzing dioxins in grams-TEQ is useful when comparing disposal or other releases of
dioxin from different sources, or different time periods, where the mix of congeners may
vary, EPA only recently began collecting comprehensive data on the individual dioxin
congeners, so trends of TRI dioxin data in grams-TEQ are not possible at this time.
Various industry sectors may dispose of or otherwise release very different mixes of
dioxin congeners, Eight industry sectors accounted for most of both the grams and
grams-TEQ of dioxin disposed of or otherwise released in 2011; however, their ranking
in terms of percentage of the total is quite different for grams and grams-TEQ, as shown
in Figures 8 and 9.
Figure 8. Grams
Percent of Total Disposal or Other Releases,
Dioxin and Dioxin-like Compounds, 2011
Figure 9. Grams-TEQ
Percent of Total Disposal or Other Releases,
Dioxin and Dioxin-like Compounds, 2011
Cement: 2%
All Others: 2%
Hazardous
Management: 2%
Paper: 1%
Electric Utilities: 1%
All Others: 1%
Chemicals: 77%
Primary Metals: 18%
Hazardous
Waste Management:
Primary Metals: 44%
In 2011, the chemical manufacturing industry accounted for 77% of the total grams of
dioxin and dioxin-like compounds disposed of or otherwise released, while the primary
metals sector accounted for 18% of the total grams. However, when TEFs are applied,
the primary metals sector accounted for 44% of the total grams-TEQ and the chemical
manufacturing industry for 17% of the total grams-TEQ.
9 Disposal or Other Releases of TRI Chemicals
2011 TRI National Analysis Overview
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Polychlorinated biphenyls (PCBs), another PBT chemical category, are no longer
manufactured or used in new products. Therefore, the disposal or other releases of
PCBs are usually a result of cleanup efforts or capacitors and transformers being taken
out of service and properly disposed of in facilities that minimize risk to human health
and the environment. PCB disposal or other releases typically fluctuate from year to
year, as shown in Figure 10, based on how many significant cleanup activities are
underway or how many PCB transformers are removed from service. Almost 99% of
disposal or other releases of PCBs are disposed of in RCRA (Resource Conservation and
Recovery Act) Subtitle C landfills at hazardous waste management facilities. Note that
in 2003, almost 22 million pounds of PCBs were disposed of in landfills, as shown in
Figure 10 by the black arrow indicating the pounds reported that year exceed the scale
of the figure. This 2003 spike in the trend was primarily due to one hazardous waste
management facility disposing of PCBs in a RCRA subtitle C landfill.
Figure 10. Disposal or Other Releases, 2003-2011:
Polychlorinated Biphenyls (PCBs)
-O
c
o
Q.
6,000,000
5,000,000
4,000,000
3,000,000
2,000,000
1,000,000
2003 value was
22 million lbs
Total Off-site Disposal or Other Releases
On-site Land Disposal or Other Releases
I On-site Underground Injection
I On-site Surface Water Discharges
I On-site Air Releases
2003 2004 2005 2006 2007 2008 2009 2010 2011
Year
10 Disposal or Other Releases of TRI Chemicals 2011TRI National Analysis Overview
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Among the chemicals that are reported to TRI, there are about 180 known or suspected
carcinogens, which EPA sometimes refers to as Occupational Safety & Health
Administration (OSHA) carcinogens. Figure 11 shows that the air releases of these
carcinogens decreased by 50% between 2003 and 2011, with a 3% (1.9 million pounds)
decrease from 2010 to 2011.
Figure 11. Air Releases, 2003-2011:
Carcinogens
140
2003 2004 2005 2006 2007 2008 2009 2010 2011
Year
Trends in pounds of disposal or other releases do not account for potential risk of
chemical releases. Risk can vary depending on chemical toxicity, how chemicals are
released (e.g., to the air or water), where chemicals travel, and where human populations
are located.
To provide information on the potential risk of disposal or other releases, the TRI
program presents its data from a risk-related perspective using EPA's publicly-available
Risk-Screening Environmental Indicators (RSEI) model. The model produces unitless
"scores," which represent relative chronic human health risk and can be compared to
RSEI-generated scores from other years or geographical regions.
RSEI scores are calculated using on-site releases to air and water, transfers to Publicly
Owned Treatment Works (POTWs), and transfers for off-site incineration as reported to
TRI. Note that other release pathways, such as land disposal, are not currently modeled
in RSEI. The scores are calculated based on many factors including: the amount of
chemical released, the location of the release, the chemical's toxicity, its fate and
transport through the environment, and the route and extent of human exposure.
Because modeling the exposure of TRI chemicals is time and resource intensive, RSEI
data through 2010 are currently available, and updates through 2011 are scheduled to
be available in the near future.
11 Disposal or Other Releases of TRI Chemicals 2011 TRI National Analysis Overview
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Figure 12 shows the trend in the RSEI score from 2003 to 2010. Over this time period,
the RSEI score decreased by 43%, indicating that the relative risk of the TRI releases
modeled through RSEI has declined considerably since 2003.
Figure 12. RSEI Score, 2003-2010
1.000
£ 800
o
S 600
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