APPENDIX II-CE: Great Rivers Environmental
This appendix is copied from:
http://www.greatriverslaw.org/mosquito_spraying.pdf
GREAT RIVERS ENVIRONMENTAL
LEWIS C. GREEN,
FOUNDING PRESIDENT, 1924-2003
ELSA STEWARD
EXECUTIVE DIRECTOR
KATHLEEN G. HENRY
PRESIDENT
BRUCE A. MORRISON
TREASURER
MELODY
DEVELOPMENT DIRECTOR
__________
TELEPHONE (314) 231-4181
FACSIMILE (314) 231-4184
WWW.GREATRIVERSLAW.ORG
POSITION PAPER
USE OF SPRAYING TO COMBAT
I. PESTICIDES USED BY
This
summer,
of
West Nile Virus (WNV) by spraying pesticides aimed at adult mosquito
populations. News
sources
have kept residents well-informed of the potential dangers of the virus but
have
neglected
to inform the public of the hazards of pesticides. Currently,
pesticide
Anvil 2+2 ULV, which contains sumithrin and piperonyl butoxide as active
ingredients.
The County uses Aqua-Reslin, which contains permethrin and piperonyl butoxide.
Both
pesticides are mixed in a base of petroleum solvents and other undisclosed
ingredients.
A.
Short-term Exposure Toxicity to Humans
Permethrin and sumithrin
are synthetic pyrethroids, a class of compounds which
work by
paralyzing
the nervous system. They are chemically similar to pyrethrins,
toxins found in
chrysanthemum
plants.1 Human
exposure to pyrethroids may cause skin irritation,
eye irritation,
and
asthmatic symptoms.2 Larger
doses may affect the nervous system, causing loss of
1 http://ace.orst.edu/info/npic/factsheets/pyrethrins.pdf.
2 http://ace.orst.edu/info/npic/factsheets/permethrin.pdf.
coordination
or tremors.3 Very
large doses can result in dizziness, headache, nausea, muscle
twitching,
reduced energy, changes in awareness, convulsions and loss of consciousness.4
Whether
a person may experience negative effects depends on the extent of the exposure
and the
person’s
age, sex, genetic makeup, lifestyle, and general health characteristics.5 The EPA
recommends
daily oral exposure limits for 10 different pyrethroids
and has established
tolerances for residues of pyrethrins
and various pyrethroids in foods.6
Piperonyl butoxide
is a chemical that has no pesticide effects on its own but is added to
pyrethroids because it inhibits insects’
ability to break down pyrethroids before they take
effect.
It
has a low potential of short-term effects through direct contact.7 However, any exposure to
piperonyl butoxide
will also include exposure to a pyrethroid.
The
petroleum solvent base may also be toxic. Short-term exposure to high levels
may
cause
eye, skin, nose, throat or lung irritation; vomiting or central nervous system
depression
may
result if petroleum solvents are ingested.8 The
combination of a pyrethroid, piperonyl
butoxide, and a petroleum solvent can
lead to more severe health effects than each ingredient
taken
alone. The Material Safety Data Sheet (MSDS) for Anvil 2+2 warns that skin
contact can
result
in irritation progressing into dermatitis, and ingestion can lead to nervous
system disorders
such
as fatigue, dizziness, headaches, lack of coordination, tremors, and
unconsciousness.
Government
officials emphasize that the amount of spray is too low to cause severe
reactions.
However, New York newspapers report anecdotes of residents being doused by
spray
trucks
while standing at phone booths or coming out of their homes.9 One woman was sprayed
directly
in the face from a truck four to five feet away. Victims suffered from eye
irritation, chest
3 New York State Dept. of Health,
available at http://www.health.state.ny.us/nysdoh/ pest/anvil.htm. June 2002.
4 ATSDR, available at
http://www.atsdr.cdc.gov/tfacts155.html. September 2001.
5
6 http://www.atsdr.cdc.gov/tfacts155.html.
7 http://ace.orst.edu/info/npic/factsheets/pbogen.pdf.
8 http://www.health.state.ny.us/nysdoh/pest/scourge.htm.
9 Patricia Hurtado,
“A Price to Spray.” Newsday. September 19, 2000. Available at
http://www.safe2use.com/caipm/
00-09-19.htm.
tightness,
and nausea which persisted for several days. A local hospital reported more
than 200
calls
from residents who suspected they had been poisoned by pesticides.10
B.
Long-term Exposure Effects
Pyrethroids, including permethrin
and sumithrin, are suspected to be endocrine
inhibitors.
In
a laboratory study at Mt. Sinai School of Medicine, they were found to mimic
the hormone
estrogen
when applied to cells grown in plastic dishes.11
Estrogen-mimickers impair the body’s
natural
ability to regulate the level of hormones. In humans, increased levels of
estrogen is linked
to
breast cancer, decreased fertility, and reduced sperm count.12
Permethrin and piperonyl
butoxide are both classified by the EPA as possible
carcinogens
due
to their correlation with lung and liver tumors in mice during laboratory
experiments. The
EPA
is currently investigating the cancer effects of sumithrin
and has not yet classified the
pesticide.
The long-term and carcinogenic effects on humans are not well studied and many
of
the
potential effects given (including short-term effects) are results of animal
toxicity tests.
C.
Effects on Wildlife
Both
permethrin and sumithrin
are highly toxic to fish and bees and slightly toxic to
birds.
Piperonyl butoxide is only
mildly toxic to fish but highly toxic to other aquatic organisms
and
slightly toxic to birds.13 Wildlife
(and pets) can be exposed through direct contact, ingesting
sprayed
vegetation and insects, inhalation, or grooming.14
The toxicity to fish and birds is
particularly
significant because certain species eat mosquito eggs, larvae, or adults,
thereby
playing
a key role in the reduction of the mosquito population. Furthermore, spraying
with
pesticides
could have the contrary result of increasing mosquito populations by
eliminating their
10 Michael R. Blood, “Artist: I’m
a Victim of Skeeter Spraying.”
Available at http://www.getipm.com/articles/ny-anvil.htm.
11 Vera Go, Joan Garey, Mary S. Wolff, and Beatriz G.T. Pogo. “Estrogenic
Potential of Certain Pyrethroid
Compounds in the MCF-7 Human Breast Carcinoma Cell Line.”
Environmental Health Perspectives, vol. 107, no. 3,
March 1999, pages 173-177.
12 William C. Sugg,
III, Matthew L. Wilson, “Overkill: Why Pesticide Spraying for West Nile Virus
May Cause
More Harm Than Good.” July 2001. Available at
http://www.meepi.org/wnv/overkillma.htm.
13 http://ace.orst.edu/info/npic/factsheets/permethrin.pdf,
http://ace.orst.edu/info/npic/factsheets/pbogen.pdf.
14 http://npic.orst.edu/factsheets/wildlife.pdf.
natural
predators. Conservationists, most notably bird enthusiasts, are also concerned
about the
disturbance
of natural ecosystems. Pesticides indiscriminately kill non-target insects
also,
eliminating
a food source of fish, amphibians, and local and migratory birds. The poisons
are
also
toxic to fish, diminishing another source of food for birds. Although WNV is
extremely
lethal
to birds, environmentalists worry that using pesticides could be worse than the
virus itself.
D.
Efficacy of Mosquito Spraying
In
a joint statement on mosquito spraying, the CDC and EPA state that in order to
be
effective,
spraying must be done under extremely precise conditions: at the ideal
temperature,
with
low winds, at the time of day when mosquitoes are most active, and with
carefully
calibrated
equipment to form droplets the right size.15 Furthermore,
the spray is only effective
against
adult mosquitoes and not eggs or larvae. In an April 2001 report the CDC
stated,
“Adulticiding, the application of chemicals to kill adult
mosquitoes by ground or aerial
applications,
is usually the least efficient mosquito control technique,” and also “The most
effective
and economical way to control mosquitoes is by larval source reduction. …
Control of
adult
mosquito populations by aerial application of insecticides is usually reserved
as a last
resort.”16 The EPA and CDC advocate Integrated Pest Management
(IPM). They explain, “IPM
is
an ecologically based strategy that relies heavily on natural mortality factors
and seeks out
control
tactics that are compatible with or disrupt these factors as little as
possible. IPM uses
pesticides,
but only after systematic monitoring of pest populations indicates a need.
Ideally, an
IPM
program considers all available control actions, including no action, and
evaluates the
interaction
among various control practices, cultural practices, weather, and habitat
structure.
This
approach thus uses a combination of resource management techniques to control
mosquito
populations
with decisions based on surveillance.”17
15 http://www.epa.gov/pesticides/factsheets/mosquitojoint.htm.
16 http://www.cdc.gov/ncidod/dvbid/westnile/resources/wnv-guidelines-apr-2001.pdf.
17 http://www.epa.gov/pesticides/factsheets/mosquitojoint.htm.
In
addition to the uncertainty over whether pesticides effectively exterminate
adult
mosquitoes,
there is also a question as to whether the pesticide is effective in reducing
the
incidence
of WNV. As with any pesticide the insects which survive will be the ones that
are most
resistant
to the pesticide and will breed increasingly resistant generations. In the
past, mosquito
populations
have quickly developed resistance to DDT, malathion
(a pesticide sprayed in
Houston
and New York), and Bacillus thurengiensis israelensis (a
bacteria that kills mosquito
larvae).18 Cities must either continually increase the amount
of pesticide or spray new chemicals.
Some
municipalities must add supplementary chemicals such as temephos
which inhibit the
ability
of mosquitoes to develop resistance to the primary pesticide.19
Conservationists
also question the methods of locating WNV. Health departments tend to
assume
that dead birds indicate a high incidence of WNV since birds are highly prone
to
mortality
from the disease. In response, they mark the location of high mortality as a
hotspot of
WNV
and increase the amount of spraying. This circular reasoning ignores the
possibility that
pesticides
are also a cause of death of birds. Health authorities should conduct testing
to
ensure
that the deaths are not from pesticide poisoning. St. Louis County surveillance
data,
which
plots the occurrence of dead birds in an area, demonstrates this assumption:
“the dead
birds
on the map are not known to have died from WNV. If there is a sudden increase,
however,
it
will be obvious and there is a good chance that WNV is the cause.”20
II. ST. LOUIS COUNTY/CITY MOSQUITO ABATEMENT PLANS
A.
St. Louis County
The
County is responsible for spraying all areas except St. Louis City. The current
plan
includes
surveillance of the incidence of WNV through mosquito trapping, dead bird data,
and
human/mammalian
disease incidence data. However, the spray method is not related to
18 http://www.niaid.nih.gov/dmid/malaria/malafr/vector.htm,
http://www.nypirg.org/mosquito.html,
http://icmr.nic.in/annual/vcrc/vectorbi.pdf.
19 http://www.epa.gov/pesticides/factsheets/larvicides4mosquitos.htm.
20 http://scchealth.org/docs/wnv/wnv_data.html.
surveillance
data. Neighborhoods are sprayed on a weekly basis, though there is no schedule
posted.
There is also no mechanism for notification of residents and the County has
eliminated
the
option of “no spray zones.”
B.
St. Louis City
So
far this summer, the City vector control office has no plans for area-wide
spraying.
The
City will spray on an as-needed basis in response to surveillance data;
however, the Board of
Aldermen
may call for area-wide spraying later this summer if they believe it is
necessary. The
benefits
of an as-needed plan is that it limits the spraying to targeted areas only and
minimizes
unnecessary
spraying. The disadvantage is that giving residents notice is difficult since
there is
no
consistent schedule. City residents may call the vector control office to be
placed on a call list
and
will be called around
III. THE
PRECAUTIONARY STEPS PRIOR TO SPRAYING
In
the absence of long-term medical and environmental data, medical professionals
including
Dr. Daniel McKeel, Professor of Pathology and
Immunology at
University,
advocate the “cautionary principle” route. Concerns remaining to be addressed
include:
long-term human health risks of repeated spraying, impact on complex
ecosystems,
whether
spraying may be counterproductive to eradicating WNV, the rate mosquitoes are
developing
resistance to sprays, and the efficacy of killing adult mosquitoes through
indiscriminate
spraying. Before responding to public alarm about WNV, government officials
should
carefully weigh the threats posed by WNV against the health costs of mosquito
spraying.
A.
City and County publications should be forthcoming on the health effects of
mosquito spray.
spraying
“Anvil 2+2, a product that kills 96% to 98% of the mosquitoes in an area but is
also
completely
biodegradable within four hours.”21 Also,
“The City uses a botanical insecticide that
is
odorless and harmless to humans and pets.”22 However,
the MSDS for Anvil states that it is a
“pungent
aromatic, similar to smell of mothballs,” is extremely toxic to fish (which are
kept in
backyard
ornamental ponds), and can cause a variety of health effects to humans.
Furthermore,
the
New York State Department of Health estimates that sumithrin,
the active ingredient in
Anvil,
has a half- life of 9.4 days in soil and over 9 hours in water.23 That is, half of the amount
originally
sprayed remains after those durations. Next, sumithrin
is a man-made synthetic similar
to
toxins found in the chrysanthemum plant; the chemical itself is not a
botanical. Last, the 96%
to
98% success rate seems rather high for several reasons. First, EPA has
emphasized that
adulticide sprays are only effective
under very precise environmental conditions. Second,
pesticide
expert Barrie Webster, former head of the Pesticide Research Laboratory at the
the
reduction in mosquitoes may last only 12-36 hours.24
City
and County governments should provide websites and hotlines to ensure that
residents
ha ve access to health and safety information about
pesticides, not just WNV. They
should
inform residents of who is most at-risk of adverse health effects (children,
asthma
sufferers,
chemically sensitive people, etc.), provide information on how to limit
exposure, and
provide
information on steps to take if a person believes he has been poisoned by
spraying. Local
clinics,
hospitals, and physicians should also be notified of what pesticides are being
used, along
with
the identification and treatment of such poisoning.
21
http://stlouis.missouri.org/citygov/health/cityhealth12.PDF.
22
http://stlouis.missouri.org/citygov/health/cityhealth15.pdf.
23
24
B.
City and
Bodies
of Water and Storm Sewers.
As
noted above, pyrethroids are extremely toxic to fish
and other aquatic organisms.
Furthermore,
the Clean Water Act prohibits the discharge of pollutants into waters of the
United
States
without a permit. The Anvil 2+2 Material Safety Data Sheet states “Do not
discharge
effluent
containing this product into lakes, streams, ponds, estuaries, oceans, or other
waters
unless
in accordance with the requirements of a National Pollutant Discharge
Elimination
System
(NPDES) permit and the permitting authority has been notified in writing prior
to
discharge.”
Because FIFRA prohibits the use of a pesticide not in accordance with labeling
instructions,
the City and County should first obtain an NDPES permit if they know that
trucks
will
be spraying near bodies of water. Even if the bodies of water are not under the
authority of
the
Clean Water Act, spray operators should be instructed not to spray over ponds
which contain
fish
or other aquatic wildlife. Mosquito spraying is suspected to have a caused a
fish kill in a
goldfish
pond at Lewis Park in
C.
Risk of Adverse Health Effects Warrants Adequate Notice and
The
City’s current plan provides for only several hours notice and no opportunity
to optout.
The
County, which has a weekly schedule for spraying, does not post the schedule
online,
notify
local newspapers, and send newsletters to residents notifying them of the
schedule for
their
area. This is inadequate to protect the health of people who are chemically
sensitive,
asthmatic,
or pregnant. People may be sprayed while in their yards or coming out of their
homes
if
they do not receive adequate notice. Schools and daycare centers should be
specifically
notified
even if spraying occurs after hours, and they should be advised to wash
children’s hands
after
playing outside. While the City’s plan to only spray as-needed is a positive
step in
minimizing
the area affected, the environmental health office should take every step
possible to
notify
residents regardless of whether they have registered for the call list.
Homeowners should
have
the right to opt-out of being sprayed regardless of health concerns.
D.
Area-spraying Should Be a Last Resort
The
Board of Aldermen for
spraying.
As the CDC has stated, this should only be used a last resort. Both the City
and County
should
follow the Integrated Pest Management system advocated by the EPA and CDC. The
program
should focus on removal of breeding sites in public areas and educating
residents on
how
to eliminate breeding sites in their yards. It should take into account natural
ecosystem
dynamics,
including the effects of pesticides on non-target species and how predators
might be
used
to control the mosquito population.
E.
Pesticide Operators Must be Adequately Certified, Trained, and Protected
Pursuant
to
Department
of Agriculture and “[a]ny employee of any agency… who
is not licensed as a
certified
public operator may use restricted use pesticides only under the direct
supervision of a
certified
public operator.”25 Furthermore,
pesticide operators should receive adequate training on
personal
safety and on the proper operation of pesticide trucks. Last, they should be
given
protective
gear such as coveralls, chemical-resistant gloves, goggles, and
chemical-resistant
footwear
plus socks.
F.
Pesticides Must be Stored and Transported in a Safe Manner
Pesticides
must be stored in accordance with label directions, which mandate closed, nonleaking
containers
placed in a cool, dry place. Since these chemicals are sprayed during the
summer
months, they must be kept indoors until use. Journalists in other states have
uncovered
stories
of a pesticide being stored in the hot sun, leading to its degrading into more
toxic
chemicals
which were subsequently sprayed.26 The
containers must also be stored in an area with
secondary
containment to catch any chemical that is spilled or leaked.
Although
pyrethroids are not classified as a hazardous
material under the Department of
Transportation’s
regulations, trucks should take steps to avoid unintentional release of the
pesticide.
In case of a spill, trucks should carry absorbent materials such as sand,
sawdust, or cat
litter.
Workers should also ensure that the sprayers are working correctly and no t
leaking before
each
round of spraying.
IV. CONCLUSION
The
science on the efficacy of spraying on the incidence of WNV has been oftentimes
disparate
and muddled. In order to decide whether to spray,
establish
a panel of citizens and experts to review data on the health effects on humans
and
animals
and also take into account more effective methods of pest control such as
targeting
mosquito
larvae instead of adults and educating the public on the elimination of
breeding sites. If
government
officials decide that spraying must occur, they should notify residents as
early as
possible
prior to spraying, notify schools and daycare centers of when spraying is about
to be
done,
establish a source for medical information about pesticide hazards such as a
website or
hotline,
give homeowners or entire neighborhoods a chance to opt out of having their
property
sprayed,
and ensure residents are aware of this option. Since the goal of spraying is to
protect
public
health, it must be done in a responsible manner that minimizes adverse health
effects.
26 Erik Baard,
“Mutant Malathion: How New York’s Mosquito-Spray
Campaign Spawned a Deadly Neurotoxin.”
The Village Voice.