Report for 1995-2006 (PDF: 2080KB/46 pages)

Hazardous Substances Emergency Events Surveillance
(HSEES)
Report for 1995-2006
Minnesota Department of Health
This report is supported by funds from the Comprehensive Environmental Response, Compensation and Liability Act
(CERCLA) trust fund and the Office of Terrorism Preparedness and Emergency Response of the Centers for Disease
Control and Prevention (CDC), provided to Minnesota Department of Health under a cooperative agreement by the
Agency For Toxic Substances and Disease Registry, Public Health Service, U.S. Department of Health and Human
Services.
Minnesota Department of Health ♦ Division of Environmental Health ♦ P.O. Box 64975, St. Paul, MN 55164
651-201-4899, TTY 651-201-5797
Contents
List of Tables
List of Figures
Executive Summary
Introduction
Methods
Results and Discussion
Overview
Temporal Trends
Geographic Trends
Event type
Industries
Substances released
Victims
Evacuations
Outreach Activities
Limitations
Conclusion
References
Appendix Page iii
iv
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List of Tables
Table 1.
Cumulative data by year - Minnesota Hazardous Substances Emergency
Events Surveillance, 1995-2006
Table 2. Number of events, by county and type of event - Minnesota Hazardous
Substances Emergency Events Surveillance, 1995-2006
Table 3. Frequencies of injuries by type of event - Minnesota Hazardous
Substances Emergency Events Surveillance, 1995-2006
Table 4. Industries involved in hazardous substance events, by category Minnesota Hazardous Substances Emergency Events Surveillance, 1995
2006
Table 5. Frequency of substance categories in all events and events with victims Minnesota Hazardous Substances Emergency Events Surveillance, 1995
2006
Table 6. Top two single substances released by year - Minnesota Hazardous
Substances Emergency Events Surveillance, 1995-2006
Table 7. Events, victims, and victim/event ratio - Minnesota Hazardous Substances
Emergency Events Surveillance, 1995-2006
Table 8. Victims by category - Minnesota Hazardous Substances Emergency
Events Surveillance, 1995-2006
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List of Figures
Figure 1.
Events by year - Minnesota Hazardous Substances Emergency Events
Surveillance, 1995-2006
Figure 2.
Victim events by year - Minnesota Hazardous Substances Emergency
Events Surveillance, 1995-2006
Figure 3.
Events by day of week - Minnesota Hazardous Substances Emergency
Events Surveillance, 1995-2006
Figure 4.
Events by time of day - Minnesota Hazardous Substances Emergency
Events Surveillance, 1995-2006
Figure 5.
Events per 100,000 population, by county - Minnesota Hazardous
Substances Emergency Events Surveillance, 1995-2006
Figure 6.
Number of manufacturing events by county - Minnesota Hazardous
Substances Emergency Events Surveillance, 1995-2006
Figure 7.
Number of agricultural events by county - Minnesota Hazardous
Substances Emergency Events Surveillance, 1995-2006
Figure 8.
Event locations and major roadways - Minnesota Hazardous Substances
Emergency Events Surveillance, 1995-2006
Figure 9.
Event locations and major roadways, Twin Cities Metropolitan Area Minnesota Hazardous Substances Emergency Events Surveillance, 1995
2006
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Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
Executive Summary
The Hazardous Substances Emergency Events Surveillance (HSEES) system,
maintained by the Agency for Toxic Substances and Disease Registry (ATSDR), collects
information to describe the public health consequences of acute releases of hazardous
substances in participating states. Minnesota began participation in the HSEES system in
1995. This report summarizes events reported to Minnesota for 12 years of participation,
1995-2006. Information collected about acute events involving hazardous substances
includes the substance(s) and quantity released; time, place, and cause of the event;
number of victims and injuries sustained; response; and public health protective actions
taken.
A total of 4,566 events were reported. The most commonly reported categories of
substances were inorganic substances (14.6%) and pesticides and fertilizers (13.9%).
During 1995-2006, 283 (6.2%) events resulted in 877 victims (eight deaths). The most
frequently reported injuries were respiratory irritation, eye irritation, and gastrointestinal
system problems. Evacuations were ordered for 447 (9.8%) events.
Highlighted prevention outreach activities include contributions toward a mercury
thermometer sales ban, meth lab-related legislation, and published papers.
Introduction
The Hazardous Substance Emergency Events Surveillance (HSEES) system is
maintained by the Agency for Toxic Substances and Disease Registry (ATSDR). The
purpose of this system is to describe public health effects associated with acute
unplanned or illegal hazardous substance releases and to develop strategies to reduce
releases and related injuries.
Methods
The HSEES system maintains data about acute, unplanned or illegal releases of
hazardous substances and the associated acute public health effects. A released substance
is included if it could cause an adverse health effect, excluding petroleum-only releases.
Threatened releases of hazardous substances are included if the threat prompted a public
health action, such as an evacuation or a shelter-in-place order. Specific substances have
been identified for inclusion at any quantity released, while other substances are included
if the release is one gallon or 10 pounds or greater.
Any person who sustains at least one documented acute averse health effect within 24
hours of the event or who dies as a result of the event is an event victim. Information
collected about victims includes general symptom information, severity of injury
(measured by extent of treatment), general demographic information, distance from the
release, use of personal protective equipment, and decontamination information. HSEES
does not conduct long-term follow-up on victims to assess chronic or latent effects of
acute chemical exposure.
Health symptoms experienced by victims are classified into 11 categories, including
burns, dizziness/central nervous system symptoms, eye irritation, gastrointestinal system
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problems, headache, heart problems, heat stress, respiratory irritation, shortness of breath,
skin irritation, and trauma. An additional category called “Other” is available for
symptoms that do not correspond to the pre-defined categories. When possible, burns are
placed into subcategories of “thermal” and “chemical.” Likewise, trauma injuries are
placed into subcategories of “chemical-related” or “not chemical-related.”
ATSDR classifies substances released into 11 categories: acids, anhydrous ammonia,
bases, chlorine, mixtures, paints and dyes, pesticides, polychlorinated biphenyls (PCBs),
volatile organic compounds (VOCs), other inorganic substances, and “other” substances.
The “mixtures” category includes substances from different categories that were
combined before the release. The “other inorganic substances” category includes all
inorganic substances, except acids, bases, anhydrous ammonia, and chlorine, which have
each been assigned a separate category. The category “other” includes substances that
cannot be classified into any of the other categories. For a full explanation of categories,
see the Appendix.
The definition of an HSEES event has been updated periodically to capture relevant
events and eliminate some common events with few acute health consequences. For all
qualifying events, data collected include, when applicable: substance identity and
quantity; industries involved; event start and end time; location and area(s) affected;
transportation mode or fixed-facility equipment involved; protective public health actions
ordered; response; number of victims; and information about injuries and victim
demographics.
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Sources of preliminary information about events include the Minnesota Duty Officer, the
National Response Center, and the U.S. Department of Transportation Hazardous
Materials Incident Reporting System. Additional information is collected from company
or industry representatives, state and local emergency responders, health and safety
personnel and others with knowledge about the release.
Results and Discussion
Overview
From 1995-2006, there were 4,566 HSEES events in Minnesota. Of these, 47 (1.0%)
were threatened releases and 36 (0.8%) were part actual and part threatened releases.
There were evacuations in 447 events (9.8%) and injuries in 283 events (6.2 %), totaling
877 victims.
Temporal Trends
Overall, the number of HSEES events have been increasing over time (p < 0.001) (Table
1, Figure 1) while the number of victim events has been fluctuating, with a slight possible
increase over time (p = 0.083) (Table 1, Figure 2).
The year with the most HSEES events was 2006 (546), while the fewest were in 1995
(229), the first full year Minnesota participated in the system. Notably, the highest
number of victims were reported in 1995 (172 victims, 23 events), when two events
resulted in several victims. The fewest victims were reported in 1997 (19 victims, 16
events) (Table 1, Figure 2).
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By day of week, the most events occurred on Wednesdays (807 [17.7%]) and Tuesdays
(806 [17.7%]), and the fewest on Sundays (341 [7.5%]). The most victim events occurred
on Tuesdays (59 [20.8%]) and the fewest on Sundays (16 [5.7%]) (Figure 3). However,
Tuesdays and Saturdays had the highest percentage of events resulting in victims (7.3%),
while Wednesdays had the lowest (4.3%).
By time of day, most of the 4525 events (99.1%) with known exact time or time category
occurred during the daytime hours of 6:00 a.m. – 5:59 p.m. (3183 [70.3%]). Slightly
more events occurred in the morning hours of 6:00 a.m. – 11:59 a.m. (1641 [36.3%]) than
in the afternoon hours of 12:00 p.m. – 5:59 p.m. (1542 [34.1%]) (Figure 4).
There were 281 (99.3%) victim events for which an exact time or time category was
available. Most events with injuries (195 [69.4%]) occurred between 6:00 a.m. and 5:59
p.m. (Figure 4). The proportion of events with victims was slightly higher (86 [6.4%])
during the overnight hours of 6:00 p.m. to 5:59 a.m. than the daytime hours of 6:00 a.m.
to 5:59 p.m. (195 [6.1%]), though the difference in the proportion was not significant
(95% conference interval (-0.012, 0019)).
Geographic Trends
The seven counties of the Twin Cities metropolitan area (Anoka, Carver, Dakota,
Hennepin, Ramsey, Scott and Washington) had about half of the events, with 2280
(49.9%) in the metropolitan area and 2286 (50.1%) in the remaining counties. Of the
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seven Twin Cities counties, Hennepin County (674 events) and Dakota County (637
events) had the most events (Table 2). By size of county population, Carlton County had
the most events (55.3 events/100,000 population per year) (Figure 5).
Other geographic trends reflect the economic basis of areas in the state. In agricultural
areas of the west and southern half of the state, pesticides and fertilizer releases are
common. In the populated areas of the Twin Cities, Mankato, Rochester, Marshall, St.
Cloud, International Falls, and Duluth, manufacturing events are more prevalent. In the
far northeast, the population is less concentrated and there are few industrial and
agricultural sites, with corresponding fewer releases overall (Figures 6 and 7).
Many events occur on or near major roadways, as illustrated in the map of the event
locations (Figures 8 and 9). While some of the events represent transportation events,
many events occur in fixed-facilities that are located along the major roadways.
Event type
Fixed Facility
Fixed facilities are fixed locations such as industrial or commercial sites, schools, health
care facilities or residences. For 1995-2006, 3,410 fixed-facility events; 204 events
(6.0%) resulted in 765 victims. Evacuations were ordered in 414 (12.1%) events. The
most frequently released substance in fixed facilities, including events involving mixing
and reactions, was anhydrous ammonia (447 events). Anhydrous ammonia also produced
the most fixed-facility victims (45 events, 127 victims). The most frequently reported
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injury in a fixed facility was respiratory irritation (42.9%) (Table 3). Industries associated
with the most fixed-facility events were manufacturing (1,626 events), utilities (372
events), wholesale trade (297 events) and agriculture, forestry, fishing and hunting (261
events).
Transportation
Transportation events involve chemicals being transported by surface, air, water or
pipeline beyond the boundaries of a fixed facility. During 1995-2006, 1,156 (25.3%)
were transportation events. Seventy-nine events (6.8%) resulted in 112 victims. The most
frequently reported injury in transportation events was trauma, reported for 63 (43.8%) of
the 144 transportation-related injuries (Table 3). (A victim could sustain more than one
injury type.) Evacuations were ordered in 33 events (2.9%). The most frequently released
substance in transportation events was anhydrous ammonia (81 releases). Anhydrous
ammonia also produced the most transportation event victims (9 events, 18 victims).
Industries
The largest proportions of HSEES events were associated with manufacturing (1,690
[37.0%]) and transportation and warehousing (719 [15.7%]) (Table 4). The largest
portion of victim events occurred in the manufacturing industry (67 [23.7%]) resulting in
303 (34.5%) victims. Transportation and warehousing had the second-highest number of
events with victims (36 [12.7%]), resulting in 86 victims (9.8% of the total), but utilities
(11 events with victims, [ 3.9%]) had the second-highest number of victims (91 [10.4%]).
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The high number of victims in events at utilities was related to one mass casualty event
that resulted in several victims with minor injuries.
Substances released
A total of 5,312 substances were released in the recorded events, with an additional 89
chemicals that were threatened to be released. For all events, the number of substances
released ranged from 1 to 197. The majority of events (4,275 [93.6%]) involved release
of one substance. The most frequent type of release was spill only, with 3,140 substances
(59.1%) released in this way. There were 1,367 substances (25.7%) released by air
release only.
By category
Events were assigned a substance category based on the types of substance(s) released. If
more than one substance was released and all were of the same category, the event was
assigned that substance category. If the substances were of different categories, the event
was assigned to a “multiple substances” category.
There were 4,511 events (98.8%) that were assigned a category. The substance categories
with the most events include “other inorganic substances” (661 events [14.7%]) and
“pesticides and fertilizers” (629 events [13.9%]). The anhydrous ammonia category
(which includes ammonium hydroxide) had the highest percentage of events with victims
(18.4%) overall, but events assigned the “hetero-organics” category (26.3%) had the
highest proportion of victim events within its own category (Table 5).
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By substance
Characteristics of the most commonly released substances are described below: Anhydrous ammonia
The substance released most frequently each year was anhydrous ammonia (Table 6),
with 521 events (or 528 events including mixtures) (Table 7). Fifty-four anhydrous
ammonia events resulted in 145 victims. Anhydrous ammonia was associated with the
most victim events for each year except 1995 and 1998, when chlorine resulted in more
events with victims. The three primary sources of anhydrous ammonia releases include:
agricultural activity (267 events), refrigeration (134 events), and illegal
methamphetamine production (51 events). The other 76 events were related to industrial
processes (44 events), transportation events (24 events), mixture events (7), and one
education/research-related project.
Anhydrous ammonia: agricultural events
The widespread use of anhydrous ammonia as a fertilizer in agricultural activities creates
more occasions for release of this substance. Use of agricultural anhydrous ammonia is
most concentrated in the southern and western portions of the state. Anhydrous ammonia
releases related to agriculture are most common during the planting season (April, May,
June) and in the fall when some fields are prepared for the following spring. Other small
releases occur throughout the summer when valves on anhydrous ammonia tanks loosen
or when pressure relief valves vent due to temperature changes. Releases also occur from
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agricultural storage tanks when anhydrous ammonia theft for meth production is
attempted (see Anhydrous ammonia: methamphetamine-related events below). Overall,
agriculture-related anhydrous ammonia releases make up about half [267, (50.6%)] of all
the anhydrous ammonia releases. About 8.2% of these events resulted in victims, with a
victim to event ratio of 13 victims/100 events (Table 7).
Anhydrous ammonia: refrigeration-related events
Refrigerant releases are another major portion (134 events [25.4%]) of all anhydrous
ammonia releases. Many of these releases occur at cold storage or food processing
companies when refrigeration systems become over-pressurized and anhydrous ammonia
is released from pressure relief valves. Releases are also related to other mishaps, such as
accidentally punctured pipes or inadequate draining of pipes before maintenance.
Anhydrous ammonia theft attempts from these systems occur at times, although they are
less common than from agricultural cooperatives and farms. Anhydrous ammonia
refrigeration systems have resulted in the most anhydrous ammonia release-related
victims, with 16 events (11.9%) resulting in 73 victims and a victim to event ratio of 54
victims/100 events (Table 7).
Anhydrous ammonia: methamphetamine-related events
Illegal clandestine labs for methamphetamine have been a significant problem in the state
in recent years. During the past ten years, the HSEES system recorded 51 releases of
anhydrous ammonia (9.7%) that were known to be related to meth activity. There were
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10 events (19.6%) resulting in 23 victims. The victim to event ratio is 45 victims/100
events (Table 7).
Sulfur dioxide
The second most frequently released substance was sulfur dioxide (230 events). Unlike
anhydrous ammonia, this substance was not consistently among the most frequently
released substances by year (Table 6). Often, sulfur dioxide releases were associated with
petroleum refining or manufacturing. There were three events that resulted in 48 victims
with acute symptoms: all of these events were related to manufacturing. After 2005,
unplanned sulfur dioxide releases from emission stacks no longer qualified for HSEES
and sulfur dioxide events in the HSEES system decreased substantially.
Sulfuric acid
Sulfuric acid releases, including battery acid releases, were the third most released
substance (196 events). Several of these releases were related to manufacturing or spills
from batteries. There were 17 events with victims (8.7%) that resulted in 30 victims,
making the victim to event ratio 15 victims/100 events (Table 7).
Chlorine
Chlorine gas
There were 81 releases of chlorine gas from tanks or cylinders during 1995-2006.
Fourteen events (17.3%) resulted in 26 victims, with a victim to event ratio of 32
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victims/100 events (Table 7). These gaseous chlorine releases often resulted from
problems with water chlorination systems or manufacturing process equipment.
Mercury
The number of mercury releases reported to HSEES has risen dramatically in the past few
years, possibly because of increased public awareness after extensive news coverage of
spills in communities and schools. For 1995-2006, there were 154 releases in the HSEES
system. (Data on most mercury spills in 2005 were not collected while the HSEES case
definition was reevaluated.) There were two events with victims (1.3%) (one victim
each), but injuries were related to trauma or thermal burns and not the mercury release
directly. In some instances, people exposed to mercury received follow-up toxicological
evaluations, but no injury was reported within 24 hours of the incident. Common sources
of mercury releases were thermometers, sphygmomanometers (blood pressure gauges),
and barometers.
Victims
Injuries (Symptoms)
Twelve categories of injuries (symptoms) are collected for HSEES, with an additional
category called “Other” for injuries that do not correspond to a specific category. When
possible, burns are placed into subcategories of “thermal” and “chemical.” Likewise,
trauma injuries are placed into subcategories of “chemical related” or “not chemical
related.” The most common injury reported for all events was respiratory irritation,
reported for 584 (41.2%) of the 877 victims. Eye irritation (176 victims [12.4%]) and
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gastrointestinal system problems (160 victims [11.3%]) were the second and third most
reported injuries (Table 3).
Victim categories
Of the 877 victims recorded in the MN HSEES system for 1995-2006, most of the
victims were employees (517), followed by the general public (244) and students at
school (34). (Note: Because the “student” category was not available until 2002, 64
student victims were classified as “general public”.) The victims also included 70
responders: 18 volunteer firefighters, 17 police officers, 10 career firefighters, nine
unspecified first responders, seven company first responders, five firefighters (no
subcategory specified), and four emergency medical service responders. Category was
unavailable for 12 victims.
The victims were most often male (60.8%). Male victims comprised the greater part of
every category except the student and the “unknown” category (Table 8). By age group,
victims were most frequently between 20 and 44 years (46.9% overall), though in the
“general public” category, children 19 years and under represented 43.9% of the victims
(Table 8).
Events involving children
Children age 19 and younger were often involved in HSEES events: in 30 events, there
were 162 child victims. Excluding events recorded as mixture and reactions, the most
frequently released substances resulting in symptoms were pepper gas/pepper spray/tear
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gas (5 events), anhydrous ammonia (3 events) and chlorine-related events (3 events).
Common symptoms sustained by victims include respiratory irritation (126 victims),
gastrointestinal problems (76 victims), and headache (67 victims).
Children also played a role in initiating some HSEES events. While HSEES does not
collect information on individuals responsible for events, some of the record comments
note that one or more children were involved in event initiation, either by mishap or
purposefully. Examples of chemicals released in child-initiated events include mercury,
acids, pepper spray, bleach, and solvents. Some of these events involved injuries to other
children.
Mass casualty events
There were 17 events that involved more than 10 victims, all involving fixed-facility
locations. The event with the most victims (64) involved occupants of a school that were
affected by methyl mercaptan released from a nearby waste treatment company. Most of
the victims experienced respiratory and gastrointestinal symptoms and were evaluated at
a hospital, but none required treatment.
The chemical most commonly released in events with more than 10 victims was
anhydrous ammonia, released in four mass casualty events that resulted in a total of 60
victims. Sources of these releases were refrigeration systems (three events) and illegal
methamphetamine production (one event). While nearly all victims were treated on scene
or in a hospital and released, three required hospitalization. Common symptoms among
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victims were respiratory irritation (60 victims) and eye irritation (22 victims), chemical
burns (2 victims) and gastrointestinal symptoms (1 victim).
Chemicals classified pepper gas, pepper spray not otherwise specified and 2
chloroacetophenone also resulted in four events with 93 total victims. The first event
involved pepper gas in a school from an unidentified source. The second involved an
adolescent prank in a retail store. The third involved an accidental pepper spray release in
a restaurant and the fourth involved an apparent pepper spray release in an airport for an
unknown reason. Seventy six of the victims were treated at a hospital and released, 16
had symptoms reported by an official, and one saw a private physician. None of the
victims were admitted to a hospital. Reported symptoms were respiratory irritation (61
victims), skin irritation (21) victims), and shortness of breath (20 victims) and eye
irritation (17 victims), gastrointestinal symptoms (9 victims), headache (4 victims) and
chills (2 victims).
Other chemicals released in mass casualty events include antifreeze, a bacterial mixture,
chlorine, chlorine dioxide, chloropicrin, ethanol, hydrofluoric acid, mercaptan, and sulfur
dioxide.
Severity of injuries
Fatalities
There were no deaths caused directly by chemical releases in the MN HSEES system for
1995-2006. (Note: One death occurred several months after exposure to anhydrous
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ammonia, but this could not be noted in the HSEES record after the year’s records were
closed.)
There were six events resulting in eight fatalities that were indirectly related to a
chemical release. Six of the deaths were related to trauma and two were related to thermal
burns occurring in conjunction with a hazardous substance release. The trauma events
involved vehicle crashes (4 events) and a welding explosion. One thermal burn victim
was involved in a meth lab event and the other victim was injured in an ethanol tanker
rollover that involved a fire.
Hospitalizations
There were 68 events that resulted in at least one victim requiring hospitalization, with 98
victims hospitalized. Symptoms occurring in at least 15 of those hospitalized included
respiratory irritation (45 victims), chemical or thermal burns (27 victims), trauma (26
victims), gastrointestinal symptoms (20 victims), and eye irritation (16 victims). (A
victim could have more than one symptom.) The top three substances involved in events
requiring at least one victim to be hospitalized were anhydrous ammonia (9 events),
sulfuric acid (5 events), and chlorine gas (4 events). A bacterial/endotoxin mixture
release resulted in the most victims requiring hospitalization (13 victims) with headache,
heart problems, respiratory irritation, eye irritation, and other symptoms.
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Evacuations
There were 447 events (9.8%) involving an evacuation ordered by an official. The
number of people evacuated ranged from 1 to approximately 1,500, with about 25,200
evacuated for all events. The most common evacuation length (mode) was about 1 hour,
while the median evacuation length was 2 hours. Evacuation lengths ranged from 5
minutes to several weeks. Substances released that required evacuations most frequently
included anhydrous ammonia (108 events), chlorine gas (33 events) and mercury (28
events).
One hundred twenty-three (27.5%) events with evacuations resulted in victims, totaling
592 victims. The most common industries involved were manufacturing (40 events
[32.5%]), and education (13 events [10.6%]). Fourteen events (11.4%) with an
evacuation resulted in more than ten victims.
There were 159 events without evacuations that resulted in victims, totaling 284 victims.
(The evacuation status was unknown for one victim event.) The most common industries
of these events were agriculture (29 events [18.2%]) and wholesale trades (including
several farm cooperatives) (28 events, [17.6%]). Three events (1.9%) without an
evacuation resulted in more than ten victims. The rural nature of many of these events,
with the corresponding lower density of populated areas, might have contributed to the
decision not to evacuate and to the lower numbers of victims when compared to events
with evacuations.
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Outreach activities
In effort to reduce injuries and fatalities related to acute hazardous substances releases,
the HSEES system focuses activities on hazards identified through data analysis. Some of
the topics targeted include releases associated with anhydrous ammonia, mercury,
chlorine, pesticides and meth labs. Other outreach activities provide a general overview
of the HSEES program. Some examples of past outreach activities follow.
Anhydrous ammonia papers
The HSEES program published two papers related to anhydrous ammonia releases. One,
called “A description of agricultural releases of anhydrous ammonia in Minnesota” was
published in Chemical Health & Safety in Nov/Dec 2000 (1). This paper describes the
patterns of unplanned acute anhydrous ammonia releases related to agriculture for 1995
1997 in Minnesota. A second paper, published in March/April 2000 in Minnesota Fire
Chief magazine (2), describes anhydrous ammonia hazards and techniques for safe
response to an anhydrous ammonia release.
Mercury thermometer sales ban
When a ban on sale of mercury-containing thermometers was under consideration in the
Minnesota Legislature in 2001, MDH and others were asked for data about mercury spills
and impacts. The MN HSEES program and other state agencies provided data that
demonstrated the problems caused by mercury thermometers. The bill was passed by the
legislature, signed by the governor, and went into effect on January 1, 2002 (3). While
mercury spills from thermometers continue, it is expected that eventually the ban will
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decrease the number of mercury-containing thermometers in the state, thereby reducing
the number of mercury spills over time.
Meth Lab Program and meth response
MN HSEES has been involved in a number of projects related to illegal clandestine drug
labs (meth labs) in recent years. In the late 1990s, the number of meth labs in the state
increased, along with related injuries to general public and responders. As part of the
response, the Minnesota Department of Health supported creation of a Meth Lab Program
in 2001 to address the public health hazards associated with this illegal activity. Using
HSEES and other data, state funds were obtained to implement this program, which
focused primarily on providing education and resource connections for responders, local
community health workers, and many other groups. One Meth Lab Program activity was
a HSEES-supported conference in 2003 that featured panel discussions about safer
response to meth labs and protection of responders and the public from chemical hazards.
In 2005, HSEES data were used for an event called “Meth Day at the Capitol” that
brought attention to proposed meth-related legislation in the Minnesota legislature. The
event incorporated posters, presentations, videos, and static displays to educate legislators
and the public about meth lab hazards. Meth-related legislation, which restricted access to
meth precursors and increased penalties for meth lab-related activity, was passed and
became effective July 1, 2005 (4, 5).
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As part of an effort to evaluate the effectiveness of the meth legislation, the MN HSEES
program conducted two surveys of all Minnesota counties to determine the number of
newly discovered meth labs before and after the meth legislation implementation, and
whether the legislation would have a sustained effect. The results of the surveys showed a
sustained decrease of about 66% in newly discovered meth labs after the legislation was
implemented (6, 7).
In December 2006, the MN HSEES program presented information on illegal meth
related activity and anhydrous ammonia releases at a session at the National
Environmental Health Center/Agency for Toxic Substances and Disease Registry’s
National Environmental Public Health Conference in Atlanta, GA. This session also
covered anhydrous ammonia releases related to anhydrous ammonia refrigeration,
agricultural anhydrous ammonia, and transportation.
Aerial application article
An article concerning hazardous substance releases related to aerial application (also
called “crop dusting”) was published in the Journal of Environmental Health in
November 2005 (8). This article described number of events, substances released, and
types of injuries associated with aerial application as well as safety information.
Limitations
The HSEES system attempts to identify and collect information on all qualifying
hazardous substance release events. However, it is not known how many events occur
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that are not reported to sources available to the HSEES system. Therefore, true trends in
hazardous substance releases may slightly differ from what collected data show. The
HSEES program continuously monitors recognized hazardous substance release reporting
systems, emergency response systems, and media reports, increasing the likelihood that
more qualifying reported events will be captured.
Another limitation in this report concerns the slight variation in the HSEES case
definition over time. The case definition changes can affect the total number of events
entered each year, thereby affecting release statistics derived from the system. This report
included all reported events for 1995-2006 that met HSEES case definition at the time of
entry. Overall, long term trends have not appeared to vary substantially despite the case
definition changes.
Conclusion
The HSEES program serves as a way to monitor the trends in hazardous substances
releases within participating states and in multi-state areas. The system is unique in
providing information not only about the release event, but also in providing information
about victims. This information is useful in identifying and tracking hazards posed to the
public from acute hazardous substances releases.
The HSEES program strives to protect public health through education and outreach
activities when hazards are identified. HSEES continually seeks collaborators to join in
preventing unplanned acute hazardous substances releases and the resulting injuries.
21
References
1) Souther, L., Small-Johnson, J., Messing, R. (2000) A description of agricultural releases of anhydrous ammonia in Minnesota. Chemical Health and Safety, 7(6), 16-22. 2) Souther, L. (2000) April Showers Bring May Anhydrous ammonia Releases. Minnesota Fire Chief, 36(4), 14-16. 3) Minn. Stat. 2007 116.92, Subd. 6 4) Minn. Stat. 2007 152.02 Subd. 6 5) Minn. Stat. 2007 152.136
6) Minnesota Department of Health. 2006. Meth Labs Discovered in Minnesota in 2005. Accessed from
http://www.health.state.mn.us/divs/eh/meth/ordinance/mnmethlabs2005.pdf May 15, 2008. 7) Minnesota Department of Health. 2006. Meth Labs Discovered in Minnesota in 2005 and January to June, 2006. Accessed from
http://www.health.state.mn.us/divs/eh/meth/ordinance/mnmethlabs2006.pdf May 15, 2008. 8) Rice, N., Messing, R., Souther, L., Berkowitz, Z. (2005) Unplanned Releases and Injuries Associated with Aerial Application of Chemicals, 1995-2002. Journal of Environmental Health, 68(4), 14-18. 22
Appendix Table 1. Data by year-
Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006* Events with
victims
Type of event
Year
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
Total
Fixed
facility
193
224
194
341
287
346
338
228
321
325
271
342
3410
Transportation
36
77
71
36
61
73
76
126
117
143
136
204
1156
Total
229
301
265
377
348
419
414
354
438
468
407
546
4566
No.
substances
released
386
340
283
440
370
459
472
374
499
740
456
584
5403
No.
victims
172
73
19
66
62
83
50
85
83
64
52
68
877
No.
deaths
0
0
1
0
0
1
0
1
3
1
0
1
8
No.
23
21
16
22
24
29
19
16
30
26
26
31
283
* Numbers in the table might differ from those reported in previous years because of adjustments in
HSEES qualification requirements for events.
† Percentage of events with victims.
%†
10.0
7.0
6.0
5.8
6.9
6.9
4.6
4.5
6.8
5.6
6.4
5.7
6.2
Table 2. Number of events, by county and type of eventMinnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
Fixed facility Events
County
Aitkin
Anoka
Becker
Beltrami
Benton
Big Stone
Blue Earth
Brown
Carlton
Carver
Cass
Chippewa
Chisago
Clay
Clearwater
Cook
Cottonwood
Crow Wing
Dakota
Dodge
Douglas
Faribault
Fillmore
Freeborn
Goodhue
Grant
Hennepin
Houston
Hubbard
Isanti
Itasca
Jackson
Kanabec
Kandiyohi
Kittson
Koochiching
Lac Qui
Parle
Lake
Lake of the
Woods
Transportation Events
All Events
Events
Victim
Events
Events
Victim
Events
Evacuation
Events
Events
with
Victims
Total
Events
4
104
7
6
14
1
44
17
201
38
5
12
9
23
2
1
13
21
502
22
7
31
16
37
42
5
547
8
9
7
109
6
0
16
16
38
1
12
0
0
0
0
5
1
0
4
1
0
1
0
0
0
1
2
16
0
0
0
2
6
3
0
36
0
1
0
3
0
0
2
0
1
5
58
8
1
6
4
23
13
9
10
0
5
4
9
1
0
2
5
135
6
5
16
8
9
17
7
127
4
2
6
8
7
0
16
3
2
1
4
3
0
0
0
2
0
2
0
0
0
0
0
1
0
0
0
4
0
2
1
0
0
4
1
7
1
0
0
0
1
0
1
1
0
0
18
0
0
0
0
4
5
2
8
1
0
3
3
0
0
1
6
42
1
1
2
1
4
5
1
104
0
2
2
1
0
0
2
0
1
2
16
3
0
0
0
7
1
2
4
1
0
1
0
1
0
1
2
20
0
2
1
2
6
7
1
43
1
1
0
3
1
0
3
1
1
9
162
15
7
20
5
67
30
210
48
5
17
13
32
3
1
15
26
637
28
12
47
24
46
59
12
674
12
11
13
117
13
0
32
19
40
3
0
4
0
0
0
7
5
0
1
1
2
1
6
6
0
0
0
0
0
6
Page 1 of 3
Table 2. Number of events, by county and type of eventMinnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
Fixed facility Events
County
Le Sueur
Lincoln
Lyon
Mahnomen
Marshall
Martin
McLeod
Meeker
Mille Lacs
Morrison
Mower
Murray
Nicollet
Nobles
Norman
Olmsted
Otter Tail
Pennington
Pine
Pipestone
Polk
Pope
Ramsey
Red Lake
Redwood
Renville
Rice
Rock
Roseau
St. Louis
Scott
Sherburne
Sibley
Stearns
Steele
Stevens
Swift
Todd
Traverse
Wabasha
Wadena
Transportation Events
All Events
Events
Victim
Events
Events
Victim
Events
Evacuation
Events
Events
with
Victims
Total
Events
13
2
68
2
4
20
60
14
6
26
16
10
13
12
3
88
27
11
8
10
25
7
264
2
13
31
32
3
22
82
28
60
13
52
44
6
11
9
2
9
3
3
0
3
0
2
1
3
2
2
0
2
1
0
2
0
3
0
4
1
2
3
0
23
0
1
1
2
1
0
5
2
2
0
4
3
2
1
1
0
1
0
11
0
14
1
7
11
14
8
7
4
8
4
7
5
2
28
16
3
1
9
11
5
116
1
9
12
7
5
3
15
13
13
6
24
37
9
9
5
0
2
3
2
0
0
0
0
0
2
0
0
1
0
0
2
1
0
2
2
0
1
3
3
0
3
0
1
0
0
1
1
1
2
1
0
1
3
1
0
1
0
0
1
2
0
9
0
0
3
10
5
1
2
1
1
1
1
0
4
2
2
3
3
4
1
64
0
3
0
6
2
0
14
5
6
3
10
7
0
1
2
0
3
0
5
0
3
0
2
1
5
2
2
1
2
1
2
3
0
5
2
4
2
5
6
0
26
0
2
1
2
2
1
6
4
3
0
5
6
3
1
2
0
1
1
24
2
82
3
11
31
74
22
13
30
24
14
20
17
5
116
43
14
9
19
36
12
380
3
22
43
39
8
25
97
41
73
19
76
81
15
20
14
2
11
6
Page 2 of 3
Table 2. Number of events, by county and type of eventMinnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
Fixed facility Events
County
Waseca
Washington
Watonwan
Wilkin
Winona
Wright
Yellow
Medicine
Totals
Transportation Events
All Events
Events
Victim
Events
Events
Victim
Events
Evacuation
Events
Events
with
Victims
Total
Events
11
237
15
1
22
29
1
14
1
0
4
3
7
101
11
3
6
11
1
1
0
1
0
2
1
28
3
0
5
6
2
15
1
1
4
5
18
338
26
4
28
40
10
0
6
1
1
1
16
3410
204
1156
79
447
283
4566
Page 3 of 3
Table 3. Frequencies of injuries by type of event*Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
Fixed facility
Injury (symptom)
Burns (unspecified)
No.
injuries
%
Transportation
No.
injuries
All events
Total
%
injuries
% of
injuries
2
0.2
0
0
2
0.1
Chemical burns
40
3.1
2
1.4
42
3.0
Dizziness/central nervous system
symptoms
62
4.9
5
3.5
67
4.7
Eye irritation
152
11.9
24
16.7
176
12.4
Gastrointestinal system problems
155
12.2
5
3.5
160
11.3
Headache
116
9.1
4
2.8
120
8.5
20
1.6
0
0.0
20
1.4
0
0.0
0
0.0
0
0.0
22
1.7
0
0.0
22
1.6
547
42.9
37
25.7
584
41.2
Shortness of breath
48
3.8
2
1.4
50
3.5
Skin irritation
64
5.0
0
0.0
64
4.5
Thermal burns
28
2.2
2
1.4
30
2.1
Trauma
19
1.5
63
43.8
82
5.8
Total‡
1275
100.1
144
100.2
1419
100.1
Heart problems
Heat stress
Other
Respiratory irritation
†
* The number of injuries is greater than the number of victims (877) because a victim could have
more than one injury.
†
Of the 82 trauma injuries, one was chemical-related, 38 were not chemical related and 43 were unknown or not specified.
‡
Percentages do not total 100% because of rounding.
Table 4.─Industries involved in hazardous substance events, by category
Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
Industry
Category
Total events
Number
Events with victims
%
Number
Percent
events
with
victims
%
Total
number of
victims
Maximum
victims in
a single
event
Accommodation
and Food
Services
25
0.5
5
1.8
20.0
24
12
Administration
and Support and
Waste
Management
and Remediation
Services
34
0.7
2
0.7
5.9
2
1
Agriculture,
Forestry, Fishing
and Hunting
482
10.6
34
12.0
7.1
39
4
Arts,
Entertainment,
and Recreation
62
1.4
11
3.9
17.7
37
16
Construction
44
1.0
3
1.1
6.8
4
2
Education
Services
98
2.1
15
5.3
15.3
67
38
3
0.1
1
0.4
33.3
2
2
45
1.0
3
1.1
6.7
13
11
5
0.1
0
0
0.0
0
0
1690
37.0
67
23.7
4.0
303
46
36
0.8
1
0.4
2.8
1
1
132
2.9
20
7.1
15.2
34
5
Professional
services,
Scientific and
Technical
Services
12
0.3
3
1.1
25.0
6
3
Public
administration
55
1.2
4
1.4
7.3
12
7
Real Estate,
Rental and
Leasing
19
0.4
5
1.8
26.3
13
6
Retail trade
89
1.9
8
2.8
9.0
34
21
Transportation
and
Warehousing
719
15.7
36
12.7
5.0
86
22
Utilities
396
8.7
11
3.9
2.8
91
64
Wholesale trade
465
10.2
35
12.4
7.5
59
11
Not an industry
97
2.1
15
5.3
15.5
25
7
Unknown
58
1.3
4
1.4
6.9
25
21
4566
100.0
283
100.3
6.2
877
64
Finance and
Insurance
Health Care and
Social
Assistance
Information
Manufacturing
Mining
Other (includes
residences)
Total
Table 5. Frequency of substance categories in all events and events with victimsMinnesota Hazardous Substances Emergency Events Surveillance System, 1995-2006*
All events
Substance category
No.
Events with victims
%
Percent of
events
Percent of
with
all releases victims in
with
substance
victims
category
No.
Acids
423
9.4
29
10.2
6.9
Ammonia (includes
ammonium hydroxide)
523
11.6
52
18.4
9.9
Bases
214
4.7
9
3.2
4.2
Chlorine
160
3.5
24
8.5
15.0
Formulations
14
0.3
1
0.4
7.1
Hetero-organics
19
0.4
5
1.8
26.3
Hydrocarbons
20
0.4
1
0.4
5.0
Mixture
336
7.4
22
7.8
6.5
Multiple substance category
182
4.0
39
13.8
21.4
Other‡
181
4.0
8
2.8
4.4
Other inorganic substances
661
14.7
19
6.7
2.9
Oxy-organics
313
6.9
18
6.4
5.8
Paints and dyes
149
3.3
2
0.7
1.3
Pesticides and fertilizers
629
13.9
35
12.4
5.6
Polychlorinated biphenyls
114
2.5
0
0.0
0
80
1.8
3
1.1
3.8
493
10.9
16
5.7
3.2
4511
99.7
283
100.3
N/A
†
§
Polymers
Volatile organic compounds
Total
¶
* In ATSDR-assigned categories, substances in events that involved multiple substances were counted
only once in a substance category when all the substances were associated with the same category.
If events involved multiple substances from different substance categories, they were counted only
once in the multiple substance category.
†
Substances from different categories that were mixed or formed from a reaction before the event.
‡
Not classified. §
All inorganic substances except for acids, bases, ammonia, and chlorine. ¶
Percentages do not total 100% due to rounding. Of a total of 4566 events, 55 were excluded because they were not assigned a substance category. None of these 55 events had victims.
Table 6. Top two single substances released by year*Minnesota Hazardous Substances Emergency Events Surveillance (HSEES), 1995
2006
Year
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
Substance rank (number of events)
Most frequently released
Second most frequently released
substance
substance
Anhydrous ammonia (20)
Sulfur dioxide (16)
Anhydrous ammonia (34)
Hydrogen sulfide (17)
Anhydrous ammonia (42)
Polychlorinated biphenyls (15)
Anhydrous ammonia (47)
Ethylene glycol (13) and Sulfuric acid
(13)
Anhydrous ammonia (29)
Ethylene glycol (17)
Anhydrous ammonia (30)
Ethanol (26)
Anhydrous ammonia (52)
Sulfur dioxide (20)
Anhydrous ammonia (47)
Sulfur dioxide (21)
Anhydrous ammonia (52)
Sulfur dioxide (36)
Anhydrous ammonia (42)
Sulfur dioxide (39)
Anhydrous ammonia (53)
Paint NOS (24)
Anhydrous ammonia (73)
Paint NOS (51)
* Excludes mixtures and reactions
Table 7. Events, victims, and victim/event ratio
Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
Substance
Anhydrous Ammonia
Sulfur dioxide
Sulfuric acid
Chlorine
Mercury
Event type
Number
events
Number
with
of events victims
Agricultural release
Refrigerant release
Meth labs
Ammonia mixtures
Other ammonia events
All events
All events
Single substance, excluding mixtures and reactions*
Mixures and reactions*
All events
Gas
All events
* An "other ammonia event and a "single substance, sulfur dioxide" event overlapped categories
267
134
51
7
69
528
230
171
25
196
81
154
22
16
10
0
6
54
3
11
6
17
14
2
Percent
victim
events
(%)
Number
of
Victims
Number of
victims/100
events
8.2
11.9
19.6
0.0
8.7
10.2
1.3
6.4
24.0
8.7
17.3
1.3
35
73
23
0
14
145
48
19
11
30
26
2
13
54
45
0
20
27
21
11
44
15
32
1
Table 8. Victims by category - Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
Sex
Employees
General public
Students
Responders
Unknown
Total
Employees
General public
Students
Responders
Unknown
Total
NA = Not available
Total (n)
517
244
34
70
12
877
≤19
20
107
34
1
0
162
%
59.0%
27.8%
3.9%
8.0%
1.4%
100.0%
M
373
90
9
56
5
533
%
72.1%
36.9%
26.5%
80.0%
41.7%
60.8%
%
3.9%
43.9%
100.0%
1.4%
0.0%
18.5%
20-44
299
70
0
41
1
411
%
57.8%
28.7%
0.0%
58.6%
8.3%
46.9%
F
130
69
25
5
2
231
Age (years)
45-64
94
25
0
8
5
132
%
25.1%
28.3%
73.5%
7.1%
16.7%
26.3%
NA
14
85
0
9
5
113
%
18.2%
10.2%
0.0%
11.4%
41.7%
15.1%
>64
11
2
0
0
0
13
%
2.7%
34.8%
0.0%
12.9%
41.7%
12.9%
%
2.1%
0.8%
0.0%
0.0%
0.0%
1.5%
NA
93
40
0
20
6
159
%
18.0%
16.4%
0.0%
28.6%
50.0%
18.1%
Figure 1. Events by year-
Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
600
546
Trendline y = 21.629x + 240.08
(p < 0.001)
500
468
438
Number of Events
419
400
414
407
377
354
348
301
300
265
229
200
100
0
1995
1996
1997
1998
1999
2000
2001
Year
2002
2003
2004
2005
2006
Figure 2. Victim events by yearMinnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
35
Trendline: y = 0.7308x + 18.833
(p = 0.083)
29
Number of Events
30
25
31
30
26
26
2004
2005
24
23
22
21
19
20
16
16
15
10
5
0
1995
1996
1997
1998
1999
2000
Year
2001
2002
2003
2006
Figure 3: Events by Day of Week-
Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
900
807
806
800
740
732
728
700
Number of Events
600
500
Events
Victim Events
412
400
341
300
200
100
46
59
16
35
50
47
30
0
Sun.
Mon.
Tues.
Wed.
Day of Week
Thurs.
Fri.
Sat.
Figure 4: Events by Time of Day-
Minnesota Hazardous Substances Emergency Events Surveillance, 1995-2006
1800
1641
1600
1542
1400
Number of Events
1200
1000
789
800
600
Events
Victim Events
553
400
200
101
94
24
62
0
00:00 a.m. - 05:59 a.m.
06:00 a.m. - 11:59 a.m.
12:00 p.m. - 5:59 p.m.
Time Range
6:00 p.m.- 11:59 p.m.
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