Draft
2/18/86
AMBIENT AQUATIC LIFE WATER QUALITY CRITERIA FOR
CHLORPYRIFOS
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
ENVIRONMENTAL RESEARCH LABORATORIES
DULUTH, MINNESOTA
NARRAGANSETT, RHODE ISLAND
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NOTICES
This document has been reviewed by the Criteria and Standards Division,
Office of Water Regulations and Standards, U.S. Environmental Protection
Agency, and approved for publication.
Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
This document is available to the public through the National Technical
Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161.
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FOREWORD
Section 304(a)(l) of the Clean Water Act of 1977 (P.L. 95-217)
requires the Administrator of the Environmental Protection Agency to
publish water quality criteria that accurately reflect the latest scientific
knowledge on the kind and extent of all identifiable effects on health
and welfare that might be expected from the presence of pollutants in any
body of water, including ground water. This document is a revision of
proposed criteria based upon a consideration of comments received from
other Federal agencies, State agencies, special interest groups, and
individual scientists. Criteria contained in this document replace any
previously published EPA aquatic life criteria for the same pollutant(s) .
The term "water quality criteria" is used in two sections of the
Clean Water Act, section 304(a)(l) and section 303(c)(2). The term has a
different program impact in each section. In section 304, the term
represents a non-regulatory, scientific assessment of ecological effects.
Criteria presented in this document are such scientific assessments. If
water quality criteria associated with specific stream uses are adopted
by a State as water quality standards under section 303, they become
enforceable maximum acceptable pollutant concentrations in ambient waters
within that State. Water quality criteria adopted in State water quality
standards could have the same numerical values as criteria developed
under section 304. However, in many situations States might want to
adjust water quality criteria developed under section 304 to reflect
local environmental conditions and human exposure patterns before incorporation
into water quality standards. It is not until their adoption as part of
State water quality standards that criteria become regulatory.
Guidelines to assist States in the modification of criteria presented
in this document, in the development of water quality standards, and in
other water-related programs of this Agency, have been developed by EPA.
James M. Conlon
Acting Director
Office of Water Regulations and Standards
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ACKNOWLEDGMENTS
Loren J. Larson
(freshwater author)
University of Wisconsin-Superior
Superior, Wisconsin
Jeffrey L^ Hyland
Robert E. Hillman
(saltwater authors)
Battelle New England Laboratory
Duxbury, Massachussetts
Charles E. Stephan
(document coordinator)
Environmental Research Laboratory
Duluth, Minnesota
David J. Hansen
(saltwater coordinator)
Environmental Research Laboratory
Narragansett, Rhode Island
Clerical Support:
Terry L. Highland
Shelley A. Heintz
IV
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CONTENTS
Page
Foreword iii
Acknowledgments . iv
Tables vi
Introduction I
Acute Toxicity to Aquatic Animals 4
Chronic Toxicity to Aquatic Animals 6
Toxicity to Aquatic Plants 7
Bioaccumulation 9
Other Data 9
Unused Data . ." 13
Summary 15
National Criteria 16
References 39
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TABLES
Page
1. Acute Toxicity of Chlorpyrifos to Aquatic Animals 18
2. Chronic Toxicity of Chlorpyrifos To Aquatic Animals 24
3. Ranked Genus Mean Acute Values with Species Mean Acute-Chronic
Ratios 26
4. Toxicity of Chlorpyrifos to Aquatic Plants 29
5. Bioaccumulation of Chlorpyrifos by Aquatic Organisms 30
6. Other Data on Effects of Chlorpyrifos on Aquatic Organisms .... 31
VI
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Introduction*
Chlorpyrifos** is one of several organophosphorus compounds developed
in the 1960s to replace persistent organochlorine pesticides. It is
the active ingredient in various products designed to control a variety
of pests including fire ants, turf and ornamental plant insects, mosquitos,
cockroaches, termites, lice and hornflies. In the agricultural industry
in the United States, chlorpyrifos is used primarily to control pests on
cotton, peanuts, and sorghum. It also is used extensively in the forest
industry and is directly applied to aquatic environments in mosquito,
midge, and blackfly abatement projects. Gray (1965) and Marshall and
Roberts (1978) have reviewed its composition and physical and chemical
properties.
Chlorpyrifos is available for pesticide applications as emulsifiable
concentrates, wettable powders, dusts, granules, and controlled-release
polymers. The resulting concentrations of chlorpyrifos in water and its
persistence varies from one form to another. In general, emulsifiable
concentrates and wettable powders produce a large increase in chlorpyrifos
concentrations immediately after application. The concentration in water
rapidly declines as chlorpyrifos is sorbed onto sediments and suspended
organics. Granules and controlled-release forms do not produce as
rapid an increase in the concentration in water, but the resulting con-
centration has a longer duration.
* An understanding of the "Guidelines for Deriving Numerical National Water
Quality Criteria for the Protection of Aquatic Organisms and Their Uses"
(Stephan et al. 1985), hereafter referred to as the Guidelines, is necessary
in order to understand the following text, tables, and calculations.
**Dursban® and Lorsban® are trade names owned by the Dow Chemical Company,
Midland, MI for chlorpyrifos.
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The percentage of active ingredient in available formulations varies
considerably, both between formulations and within a single formulation
over time as manufacturers' specifications change. Such variations presumably
result in large changes in the amount, and possibly the identity, of the
unspecified ingredients. These ingredients are considered inert, although
technical-grade chlorpyrifos has generally been found to be more toxic
than an equal quantity of active ingredient in a formulation (Darwazeh and
Mulla 1974; Jarvinen and Tanner 1982; Siefert et al. 1984). For this
reason, the effects of the inert ingredients can not be discounted.
Furthermore, under normal application conditions, the commercial formulations
are often combined with petroleum products, such as No. 2 diesel oil and
kerosene, to increase the rate of dispersal. Such solvents have been shown to
have significant toxic effects in addition to those associated with
chlorpyrifos (Jamnback and Frempong-Boadu 1966; Wallace et al. 1973).
The toxicity of chlorpyrifos is probably the result of metabolic
conversion to its oxygen analogue, chlorpyrifos-oxon, and its subsequent
inhibition of various enzymes (e.g., cholinesterases, carboxylases,
acetylcholinesterases, and mitochondrial oxidative phosphorylases).
Interference with acetylcholinesterase (AChE) is generally accepted to be
the major mode of action of organophosphorus pesticides. AChE inhibition
results in accumulation of the neurotransmitter, acetylcholine, in synapes,
and disruption of normal neural transmission. Although even substantial
reductions in brain AChE activity have not always been fatal to fish, the
effect of this condition on such functions as feeding and reproduction
in nature is not known.
Chlorpyrifos enters both freshwater and saltwater ecosystems primarily
by direct application to mosquito habitats, as drift from spraying of
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agricultural areas, and on particles eroded from treated areas. Because
of its affinity for organic soils, little leaching occurs. When unbound
chlorpyrifos enters an aquatic system, it appears to be rapidly sorbed to
suspended organics and sediment, although some is removed by volatilization
and degradation. Its penetration into sediment appears to be shallow,
with most occurring in the upper several millimeters. Menzie (1969) reported
that chlorpyrivfos remained stable for long periods of time under Che
acidic conditions (pH = 5 to 6) found in some salt marshes.
Use of slow-release polymers probably results in differential
exposure, both in concentration and duration, between benthic and pelagic
organisms. Organisms inhabiting the water-sediment interface probably
receive larger and more sustained concentrations than free-swimming
organisms. Evans (1977) found concentrations of chlorpyrifos that were
still toxic to mosquito larvae one year after application of a slow-release
polymer formulation to a natural pond.
Because chlorpyrifos is rapidly metabolized by fish, with 3,5,6-
trichloro-2-pyridinol being the major product (Marshall and Roberts,
1978), concentrations in wild fishes (Clark et al. 1984; Mulla et al.
1973) and cultured or experimental fishes (Macek et al. 1972; Siefert et
al. 1984; Winterlin et al. 1968) are generally low. Braun and Frank
(1980), Hughes (1977), Hughes et al. (1980), Hurlbert et al. (1970),
Macalady and Wolfe (1985), Nelson and Evans (1973), Rawn et al. (1978),
Siefert et al. (1984), and Winterlin et al. (1968) have reported
concentrations of chlorpyrifos in natural sediment and water samples.
Unless otherwise noted, all concentrations reported herein are
expressed as chlorpyrifos, not as the material tested. Whenever adequately
justified, a national criterion may be replaced by a site-specific criterion
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(U.S. EPA 1983a), which may include not only site-specific criterion
concentrations (U.S. EPA 1983b), but also site-specific durations of
averaging periods and site-specific frequencies of allowed excursions
(U.S. EPA 1985). The latest literature search for information for this
document was conducted in February, 1985; some newer information was also
used.
Acute Toxicity to Aquatic Animals
Usable data on the acute toxicity, according to the Guidelines, of
chlorpyrifos to freshwater animals is available for seven fish species
and eleven invertebrate species. Although invertebrates are among the
most sensitive and most resistant species, the nine most sensitive species
are invertebrates. Although data are available for eighteen species, no
data are available for a planktonic crustacean, and the snail, Aplexa
hypnorum, is the only one of the eighteen that is not an arthropod or a
fish. Within arthropods and fishes separately, and within all species
combined, there appears to be an inverse relationship between size and
sensitivity to chlorpyrifos.
Species Mean Acute Values (Table 1) were calculated as geometric means
of the available acute values, and then Genus Mean Acute Values (Table 3)
were calculated as geometric means of the available freshwater Species
Mean Acute Values. The most sensitive genus, Gammarus, is more than
4,300 times more sensitive than the most resistant genera, Aplexa, Carassius,
and Ictalurus, but the four most sensitive genera are within a factor of
4, and all are invertebrates. Acute values are available for more than
one species in each of two genera, and the range of Species Mean Acute
Values within each genus is less than a factor of 3. The freshwater
Final Acute Value for chlorpyrifos was calculated to be 0.1669 Mg/L
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using the procedure described in Che Guidelines and the Genus Man Acute
Values in Table 3. Thus the freshwater Final Acute Value is higher than
the Species Mean Acute Value for one of three amphipods in the genus Gammarus.
Tests of the acute toxicity of chlorpyrifos to saltwater animals have
been conducted with three species of invertebrates and ten species of
fish (Table 1). The range of acute values extends from 0.01 ng/L for
adult Korean shrimp, Palaemon macrodactylus, (Earnest 1970) to 1,991 pg/L
for larvae of the eastern oyster, Crassostrea virginica, (Borthwick and
Walsh 1981). Only two species of saltwater arthropods have been tested
and were up to 40 times more sensitive than the most sensitive fish species.
The range of acute toxicity values for fish is narrower than for invertebrates,
with LCSOs extending from 0.4 ug/L for 14-day-old larvae of the tidewater
silver-side, Menidi-a peninsulae, (Borthwick et al. 1985) to 520 yg/L for
juveniles of the Gulf toadfish, Opsanus beta, (Hansen et al. 1986).
Borthwick et al. (1985) conducted a series of 96-hr acute tests
under both static and flow-through conditions with four different ages
of larvae of three estuarine fishes (Table 1). LCSOs ranged from 0.4 to
5.0 pg/L for all tests. In static tests, 14-day-old larvae were more sensitive
than newly hatched or 28-day larvae of all species. In flow-through
tests, relative sensitivities of the ages were similar to those in static
tests for tidewater silverside, decreased with age for Atlantic silverside,
and differed little for California grunion (Table 1).
Of the ten genera for which saltwater Genus Mean Acute Values are
available, the most sensitive genus, Mysidopsis, is about 57,000 times
more sensitive than the most resistant genus, Crassostrea (Table 3).
Acute values are available for more than one species in each of two
genera, and the range of Species Mean Acute Values within each genus is
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less Chan a factor of 5.7. Although values are available for ten genera,
and eight families, five of the eight families are in the phylum Chordata.
A saltwater Final Acute Value of 0.007591 Mg/L was calculated using the
Genus Mean Acute Values in Table 3. Because values are available for
only ten genera and the range of values for the four most sensitive genera
is a factor of 30, the saltwater FAV is a factor of 4.6 lower than the
lowest Genus Mean Acute Value.
Chronic Toxicity to Aquatic Animals
Usable data on the chronic toxicity of chlorpyrifos are available
for only one freshwater species, the fathead minnow. Chronic values for
technical-grade and encapsulated material were 2.26 pg/L and 3.25 Mg/L>
respectively, in early life-stage tests (Jarvinen and Tanner 1982).
Growth over the 32-day test was the most sensitive parameter with
technical-grade chlorpyrifos, whereas with the encapsulated formulation,
growth and survival were equally sensitive. In a life-cycle test with
the same species (Jarvinen et al. 1983), unacceptable effects occurred at
0.41 jJg/L in the first generation and at 0.12 |Jg/L in the second generation,
showing rather poor agreement between the early life-stage test and the
life-cycle test. Based on these results, the acute-chronic ratio for
chlorpyrifos is greater than 1,417 with the fathead minnow. Jarvinen et
al. (1983) also estimated the chronic effect of chlorpyrifos on the
viable biomass recruitment of a natural population of the fathead minnow.
Data on the chronic toxicity of chlorpyrifos to saltwater animals are
available for the mysid, Mysidopsis bahia, and six fishes. In the 28-day
life-cycle test with the mysid, survival and reproduction were reduced at
42 pg/L, and growth was significantly reduced at a nominal concentration
of 0.004 Mg/L (McKenney et al. 1981). This nominal concentration, which
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was less than the limit of detection of the analytical method used, is
likely representative of the actual concentration because the test con-
centrations that could be measured averaged 10 _+ 2.5% of the nominal con-
centrations. Of the six saltwater fishes exposed to chlorpyrifos in
early life-stage toxicity tests, the California grunion was the most
sensitive. Decreased weight was the most sensitive endpoint for this
species (Goodman et al. 1985a), the sheepshead minnow (Gripe et al.
Manuscript), and the gulf toadfish (Hansen et al. 1986). Decreased
survival was the most sensitive endpoint with the three species of Menidia,
although growth was also affected with two of these species (Goodman et
al. 1985b).
The Species Mean Acute-Chronic Ratios for the seven saltwater species
range from 2.388 to 228.5, whereas that for the freshwater fathead minnow
is greater than 1,417. However, the ratios for the five most sensitive
species only range from 2.388 to 12.50. Thus it seems reasonable to
calculate the Final Acute-Chronic Ratio for chlorpyrifos as the geometric
mean of these five. Division of the freshwater and saltwater Final Acute
Values by the Final Acute-Chronic Ratio of 5.016 results in Final Chronic
Values of 0.03327 ug/L and 0.001513 tJg/L, respectively. The freshwater
value is about a factor of four lower than the 0.12 Mg/L that affected the
fathead minnow, which is an acutely insensitive species. The saltwater
value is a factor of two lower than the chronic value for the most acutely
sensitive saltwater species, Mysidopsis bahia.
Toxicity to Aquatic Plants
Several field studies have examined the effects of chlorpyrifos on
phytoplankton under more or less natural conditions (Brown et al. 1976;
Butcher et al. 1975,1977; Hughes et al. 1980; Hurlbert 1969; Hurlbert et
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al. 1972; Papst and Boyer 1980). All used an emulsifiable concentrate
of chlorpyrifos which makes them inappropriate for inclusion in Table 4,
but the general trends identified are germaine to a discussion of the
effects of chlorpyrifos under natural conditions. With the exception of
Brown et al. (1976), all observed increased phytoplankton numbers after
application of chlorpyrifos. This change is generally accepted not to be
a direct effect, but rather a result of changes in the herbivore-algal
relationship caused by large reductions in predatory zooplankton populations.
Papst and Boyer (1980) attempted to substantiate this hypothesis experimentally
by following concentrations of pheopigments, the major chlorophyll degradation
product of herbivory,' after chlorpyrifos application. Although they found
reductions in pheopigments, the effect was delayed. They did observe rapid
increases in microzooplankton (e.g., rotifers) numbers immediately after
chlorpyrtfos application, presumably due to reduced competition with
macrozooplankton. Other studies have also observed an increase in micro-
zooplankton after chlorpyrifos treatment (Hughes 1977; Hurlbert et al.
1970,1972; Siefert et al. 1984). Although increased phytoplankton numbers
can be explained by release from herbivory, another possible factor is
increased phosphate concentration from decomposition of chlorpyrifos and
from decomposition of intoxified organisms (Butcher et al. 1977).
The concentrations of chlorpyrifos reducing growth or survival of
six saltwater species of phytoplankton range from 138 to 10,000 tJg/L
(Tables 4 and 6). These concentrations are well above those that are
acutely lethal to saltwater animals. Therefore, criteria derived using
data on the toxicity of chlorpyrifos to saltwater animals will probably
also protect saltwater plants.
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Bioaccmaulation
Although chlorpyrifos is hydrophobia, which would suggest its
accumulation in tissues, this is offset by its rapid metabolism (Kenaga
and Goring 1980; Marshall and Roberts 1978). With the fathead minnow,
Jarvinen et al. (1983) found a mean bioconcentration factor (BCF) of 1,673
after 60 days (Table 5). In a review, Kenaga and Goring (1980) cite
results of an unpublished study reporting a BCF in an unnamed fish of 450.
Data on the uptake of chlorpyrifos are available for five species of
saltwater fish (Table 5). In two early life-stage tests with the gulf
toadfish, Opsanus beta, the BCF increased from 100 to 5,100 as the
concentration of chlorpyrifos in the test solution increased from 1.4 to
150 ug/L (Hansen et al. 1986). Cripe et al. (Manuscript) found that the
BCF with the sheepshead minnow depended on the availability of food as
well as the concentration of chlorpyrifos in water (Tables 5 and 6).
No U.S. FDA action level or other maximum acceptable concentration
in tissue is available for chlorpyrifos, and, therefore, no Final Residue
Value can be calculated.
Other Data
Additional data on the lethal and sublethal effects of chlorpyrifos
on aquatic organisms are given in Table 6. Because both chlorpyrifos and
the mosquitofish are used in mosquito control programs, several studies
have been conducted on the effects of chlorpyrifos oh the survival and
effectiveness of mosquitofish as a predator of mosquito larvae. Hansen
et al. (1972) reported a 24-hr LC50 of 4,000 iJg/L for this fish. A 36-hr
LC50 of: 215 to 230 Mg/L was reported by Ferguson et al. (1966), whereas a
72-hr LC50 of 0.19 to 0.22 \tg/L was reported by Ahmed (1976). After a
24-hr exposure to 5.0 |jg/L, Johnson (1977a, 1978a) observed a decreased
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thermal tolerance in mosquitofish. Hansen et al. (1972) found that
mosquitofish chose clean water when given a choice between clean
water and 100 pg chlorpyrifos/L in laboratory experiments.
For rainbow trout, the 96-hr LCSOs at 1.6, 7.2, and 12.7°C were 51, 15,
and 7.1 ug/L, respectively (Macek et al. 1969). Increased toxicity of
chlorpyrifos with increased temperature was thought to be the result of
either increased metabolism producing lower concentrations of dissolved
oxygen and higher metabolic wastes, or increased enzyme activity converting
chlorpyrifos to its more toxic form, chlorpyrifos-oxon. In a 24-hr
exposure to 100 Mg/L> Atlantic salmon had a 4°C lower temperature preference
(Peterson 1976).
Because of the widespread use of chlorpyrifos as a mosquito larvicide,
many toxicity studies have used various species of mosquito larvae as
test organisms. Unfortunately, many studies have followed guidelines set
forth by the World Health Organization on testing of pesticides. These
guidelines prescribe a 24-hr test duration, making results unusable for
derivation of water quality criteria.
As would be expected, chlorpyrifos is highly toxic to mosquitos.
Rettich (1977) reported 24-hr LCSOs of 0.5 to 3.5 yg/L for 4th instars
of 6 species of the genus Aedes. For ^. aegypti, a species not tested by
Rettich, Saleh et al. (1981) cited 24-hr LCSOs of 0.0011 and 0.0014
Mg/L for 2nd and 4th instars, respectively. Reports of 24-hr LCSOs for 4th
instars of various Culex species range from 0.41 (jg/L to 2.0 yg/L (Ahmed
1976; Helson et al. 1979; Rettich 1977). For £. pipiens Saleh et al.
(1981) found a 24-hr LC50 of 0.0052 pg/L.
Chlorpyrifos is also used to control noxious midge populations (Ali
and Mulla 1978a,1980; Mulla and Khasawinah 1969; Mulla et al. 1971;
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Thompson et al. 1970). The 24-hr LCSOs for various midges generally
range from 0.5 yg/L to 40 Mg/L (All and Mulla 1978a,1980; Mulla and
Khasawineh 1969) although a value of 1,470 pg/L was reported for Cricotopus
decorus (Ali and Mulla 1980).
Ahmed (1977) determined 24-hr LCSOs with 6 species of aquatic coleoptera
and observed a range of 4.6 to 52 pg/L. Levy and Miller (1978) observed
the delayed effects of 24-hr exposures to 1.0 and 4.0 pg/L on a planarian,
Dugesia dorotocephala, over 108 hr. They reported no significant effects
at either concentration.
Winner et al. (1978) used a single concentration of an eraulsifiable
concentrate in a study of the effects on a mennithid nematode parasite of
mosquito larvae. They examined toxicity to infectious, parasitic, post-parasitic,
and embryo stages of Che nematode. Rawn et al. (1978) investigated the
effect of various sediments on the toxicity of chlorpyrifos to larvae of
a mosquito in artificial ponds. They found lower toxicity and lower
concentrations in water in sod-lined ponds compared to sand-lined ponds
at equal application rates. Macek et al. (1972) conducted a field study
which included analysis of fish brain AChE activity, fish stomach contents,
residues in fish and water, numbers of larval insects, and numbers of
emerging insects. Siefert et al. (1984) conducted an extensive survey of
changes within a natural pond after chlorpyrifos was applied using methods
employed by pest control authorities. Their study included analysis of
water quality, fish and invertebrate populations, and associated laboratory
studies.
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Schaefer and Dupras (1970) examined the effect of polluted waters
oh the stability of chlorpyrifos in the field. As part of a laboratory
study, El-Refai et al. (1976) tested the effectiveness of a simulated
water treatment facility in lowering toxicity of Nile River water spiked
with chlorpyrifos. They found a 33% decrease Ln toxicity with alum
treatment, and no significant change with sand filtration.
Jamnback and Frempang-Boadu (1966), Mohsen and Mulla (1981), and
Muirhead-Thomson (1978,1979) observed delayed effects after short exposures.
Among saltwater species, juvenile brown shrimp, Penaeus aztecus,
were the most sensitive with a 48-hr EC50 of 0.32 iJg/L (U.S. Bureau of
Commercial Fisheries 1965; Lowe et al. 1970). Other 48-hr EC50s are 1.5
IJg/L for juvenile grass shrimp, Palaemonetes pugio, 2.4 Mg/^ for the pink
shrimp, Penaeus duorarum, and 5.2 ^g/L for the blue crab, Callinectes sapidus.
For the eastern oyster the 96-hr ECSOs based on shell deposition range
from 270 to 340 pg/L.
The 48-hr LCSOs for fish ranged from 3.2 [Jg/L for the longnose
killifish, Fundulus similis, to 7 gg/L for the spot, Leiostomus xanthurus,
to over 1,000 Mg/L for the sheepshead minnow, Cyprinodon variegatus.
The most sensitive effect on a fish species was a reduction in growth of
the California grunion, Leuresthes tenuis, exposed to 0.62 Mg/L for 26 days
(Goodman et al. 1985a). Acetylcholinesterase activity in the brain of
adult mummichogs, Fundulus heteroclitus, was inhibited by 2.1 }Jg/L
(Thirugnanam and Forgash 1977).
The effect of chlorpyrifos on benthic communities was investigated
by Togatz et al. (1982). In communities exposed in the laboratory for 8
weeks during colonization, total faunal species richness and the abundance
of arthropods and molluscs were reduced by concentrations from 0.1 to 8.5
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Mg/L. For communities previously colonized in the field, the number of
arthropods was reduced by 5.9 Mg/^> but not by 1.0 ug/L.
Unused Data
Some; data on the effects of chlorpyrifos on aquatic organisms were
not used because the studies were conducted with species that are not
resident in North America (e .g. , Moorthy et al. 1982). Results of tests
reported by Ali (1981), Ferguson et al. (1966), Naqvi (1973), and Nelson and
Evans (1973) were not used because the test organisms probably had been
previously exposed to pesticides or other pollutants. Marshall and Roberts
(1978) and Ramke (1969) only presented data that had been published
elsewhere.
Data were not used if the test was on a commercial formulation (e.g.,
Atallah and Ishak 1971; Birmingham and Colman 1977; Chang and Lange 1967;
Hurlbert et al. 1970; Ledieu 1978; Muirhead-Thomson 1970; Mulla et al.
1973; Rettich 1979; Roberts and Miller 1971; Scirocchi and D'Erme 1980;
Siefert et al. 1984; Smith et al. 1966) or if the source of the chlorpyrifos
was not adequately described (e.g., Ali and Mulla 1976,1977; Boike and
Rathburn 1969; Gillies et al. 1974; Johnson 1977b,1978b; Kenaga et al.
1965; Micks and Rougeau 1977; Muirhead-Thomson and Merryweather 1969;
Ruber and Kocor 1976; Thayer and Ruber 1976; Wilder and Schaefer 1969;
Zboray and Gutierrz 1979). Data were not used if the organisms were
exposed to chlorpyrifos by injection or gavage or in food (e.g., Herin et
al. 1978; Wilton et al. 1973), if chlorpyrifos was a component of a
mixture (Meyer 1981), or if the organisms were fed during exposure in
short term tests (Karnak and Collins 1974).
The concentration of solvent was too high in the tests of Al-Khatib
(1985) and Davey et al. (1976). Barton (1970) conducted a static chronic
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test with mosquito larvae. Because polyethylene sorbs chlorpyrifos
(Brown et al. 1976; Hughes 1977; Hughes et al. 1980), toxicity tests
conducted in polyethylene test chambers were not used (e.g., Brown and
Chow 1975; Darwazeh and Mulla 1974; Dixon and Brust 1971; Hughes 1977;
Miller et al. 1973; Roberts et al. 1973a,b). Results of some laboratory
tests were not used because the tests were conducted in distilled or
deionized water without addition of appropriate salts (e.g., Jones et al.
1976; Nelson and Evans 1973; Rongsriyam et al. 1968; Steelraan et al.
1969). High control mortalities occurred in tests reported by Khudairi
and Ruber (1974). Test procedures were inadequately described by Ruber
and Baskar (1969).
BCFs obtained from microcosm or model ecosystem studies were not
used if the concentration of chlorpyrifos in water decreased with time or
if the exposure was too short (e.g., Metcalf 1974). Data from field studies
and measurements of chlorpyrifos in wild organisms were not used if the
concentrations of chlorpyrifos in water were not measured (e.g., Ali and Mulla
1976,1977,1978a,b; Axtell et al. 1979; Best 1969; Campbell and Denno 1976;
Carter and Graves 1972; Chang and Lange 1967; Chatterji et al. 1979;
Cooney and Pickard 1974; Evans et al. 1975; Fitzpatrick and Sutherland 1978;
Frank and Sjogren 1978; Hazeleur 1971; Hoy et al. 1972; Jamnback 1969;
Lembright 1968; Linn 1968; McNeill et al. 1968; Morganian and Wall 1972;
Moore and Breeland 1967; Mulla and Khasawinah 1969; Mulla et al. 1971;
Nelson et al. 1976a,b; Polls et al. 1975; Roberts et al. 1984; Steelman
et al. 1969; Stewart 1977; Tawfik and Gooding 1970; Taylor and Schoof
1971; Thompson et al. 1970; Wallace et al. 1973; Washino et al. 1968,
1972a,b; Wilkinson et al. 1971; Winterlin et al. 1968; Yap and Ho 1977)
or if the concentration in water was not uniform enough (e.g., Macek et
al. 1972).
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Summary
The acute values for eighteen freshwater species in fifteen genera
range from 0.11 ng/L for an amphipod to greater than 806 ^g/L for two
fishes and a snail. The bluegill is the most acutely sensitive fish
species with an acute value of 10 pg/L, but seven invertebrate genera are
more sensitive. Smaller organisms seem to be more acutely sensitive than
larger ones.
Chronic toxicity data are available for one freshwater species, the
fathead minnow. Unacceptable effects occurred to second generation
larvae at 0.12 Mg/L, which was the lowest concentration tested. The
resulting acute-chronic ratio was greater than 1,417.
Little information is available on the toxicity of chlorpyrifos to
aquatic plants, although algal blooms frequently follow field applications
of chlorpyrifos. The only available bioconcentration test on chlorpyrifos
with a freshwater species was with the fathead minnow and resulted in a
bioconcentration factor of 1,673.
The acute toxicity of chlorpyrifos has been determined with 13 species
of saltwater animals in 10 genera, and the acute values ranged from 0.01
Mg/L for the Korean shrimp, Palaemon macrodactylus, to 1,911 Mg/L for
larvae of the eastern oyster, Crassostrea virginica. Arthropods are
particularly sensitive to chlorpyrifos. Among the 10 species of fish
tested, the 96-hr LC50s range from 0.58 gg/L for striped bass to 520 Mg/L
for gulf toadfish; larvae are more sensitive than other life stages.
Growth of the mysid, Mysidopsis bahia, was reduced at 0.004 Mg/L in a life-
cycle test. In early life-stage tests, the California grunion, Leuresthes
tenuis, was the most sensitive of the six fishes, with growth being
reduced at 0.30 pg/L. Of the seven acute-chronic ratios that have
15
-------
been determined with saltwater species, the five lowest range from 2.388
to 12.50, whereas the highest is 228.5.
Concentrations of chlorpyrifos affecting six species of saltwater
phytoplankton range from 138 to 10,000 pg/L. BCFs ranged from 100 to
5,100 when the gulf toadfish was exposed to concentrations increasing from
1.4 to 150 ug/L. Steady-state BCFs averaged from 100 to 757 for five
fishes exposed in early life-stage tests.
National Criteria
The procedures described in the "Guidelines for Deriving Numerical
National Water Quality Criteria for the Protection of Aquatic Organisms
and Their Uses" indicate that, except possibly where a locally important
species is very sensitive, freshwater aquatic organisms and their uses
should not be affected unacceptably if the four-day average concentration
of chlorpyrifos does not exceed 0.033 yg/L more than once every three years
on the average and if the one-hour average concentration does not exceed
0.083 pg/L more than once every three years on the average.
The procedures described in the "Guidelines for Deriving Numerical
National Water Quality Criteria for the Protection of Aquatic Organisms
and Their Uses" indicate that, except possibly where a locally important
species is very sensitive, saltwater aquatic organisms and their uses
should not be affected unacceptably if the four-day average concentration
of chlorpyrifos does not exceed 0.0015 pg/L more than once every three years
on the average and if the one-hour average concentration does not exceed
0.0038 (Jg/L more than once every three years on the average.
The allowed average excursion frequency of three years is the Agency's
best scientific judgment of the average amount of time it will take an un-
stressed aquatic ecosystem to recover from a pollution event in which exposure
16
-------
to chlorpyrifos exceeds the criterion. Stressed systems, for example one in
which several outfalls occur in a limited area, would be expected to require
more time for recovery. The resiliencies of ecosystems and their abilities
to recover differ greatly, however, and site-specific criteria may be
established if adequate justification is provided.
Use of criteria for developing water quality-based permit limits and
for designing waste treatment facilities requires selection of an appropriate
wasteload allocation model. Dynamic models are preferred for the application
of these criteria. Limited data or other considerations might make their
use impractical, in which case one must rely on a steady-state model.
The Agency recommends the interim use of 1Q5 or 1Q10 for the Criterion
Maximum Concentration (CMC) design flow and 7Q5 or 7Q10 for the Criterion
Continuous Concentration (CCC) design flow in steady-state models for
unstressed and stressed systems respectively. These matters are discussed
in more detail in the Technical Support Document for Water Quality-Based
Toxics Control (U.S. EPA 1985).
17
-------
Table I. Acute Toxlcity of Chlorpyrltos to Aquatic Animals
Species
Snail (adult),
Aplexa hypnorum
Amph 1 pod ,
Gammarus fasclatus
Amph 1 pod (2 mo. old),
Gammarus lacustrls
Amph 1 pod,
Gammarus pseudol Imnaeus
Crayfish (1.8 g) ,
Orconectes immunls
Stonef ly (naiad) ,
Pteronarcel la badla
Stonef ly ( naiad) ,
Pteronarcys ca 1 1 f or n 1 ca
Stonef ly (naiad) ,
Claassenla sabulosa
Trlchopteran,
Leptocerldae sp.
Pygmy backswimmer,
Neoplea strlola
Pygmy backswl mraer,
Neoplea strlola
Crawling water beetle
(adult),
Peltodytes sp.
LC50 Species Mean
or EC50 ' Acute Value
Method* Chemical" dig/L)*** (yg/L) Reference
FRESHWATER SPECIES
F, M Technical >806
(98. 7*>
S, U Technical 0.32
S. U Technical O.I I
(91%)
F, M Encapsu- 0.18
lated*»»*
F, M Technical • 6
(98.7?)
S, U Technical 0.38
(97%)
S, U Technical 10
(97*)
S, U Technical 0.57
(91%)
S, M Encapsu- 0.77
lated™**
S, M Encapsu- 1.22
lated*»*»
S, M Encapsu- 1.56
lated1""1*
S, U Chlorpyrl- 0.8
fos
>806 Phipps and Hoi combe
1985a,b
0.32 Sanders 1972
0.11 Sanders 1969; Johnson
and Fin ley 1980
0.18 Siefert et al . 1984
6 Phipps and Ho (com be
1985a,b
0.38 Sanders and Cope 1968
10 Sanders and Cope 1968;
Johnson and Flnley 1980
0.57 Sanders and Cope 1968;
Johnson and Flnley 1980
0.77 Siefert et al . 1984
Siefert et al . 1984
1.38 Siefert et al . 1984
0.8 Federle and Collins
1976
Cutthroat trout (1.4 g),
Salmo clarklI
S, U . Technical
(97?)
18
18
Johnson and Finley 1980
-------
Table 1. (continued)
Species
Rainbow trout (0.6-1.5 g),
Salmo galrdnerl
Rainbow trout (juvenile),
Salmo galrdnerl
Rainbow trout (3.0 g),
Salmo galrdnerl
Lake trout (2.3 g),
Salvellnus namaycush
Goldfish (10.7 g),
Carass I us auratus
Fathead minnow,
Plmephales promelas
Fathead minnow (juvenile),
Plmephales promelas
Fathead minnow (0.5 g),
Plmephales promelas
Channel catfish (0.8 g),
I eta Iurus punctatus
Channel catfish (7.9 g),
Ictalurus punctatus
Blueglll (0.6 g),
Lepomls macrochIrus
Blueglll (0.8 q),
Lepomls macrochIrus
Method*
s,
F.
F,
s.
F,
s.
F.
F.
s.
F,
s.
F,
U
H
M
U
M
M
M
M
U
M
U
M
Chemical**
Technical
Technical
199.9%)
Technical
(98.7*)
Tec tin leal
(97*)
Technical
(98. 1%)
Technical
(98.7*)
Technical
(99.9$)
Technical
(98.731)
Technical
(97*)
Technical
(98.7*)
Technical
(97* )
Techn leal
(98.7*)
LC50
or EC50
(ugA)***
7.1
8.0
9
98
>806
170
203
542
280
>806
2.4
10
Species Mean
Acute Value
(ng/L) Reference
Macek at at . 1969;
Johnson and Flnley 1980
Ho Icon be et al . 1982
8.485 Phlpps and Hoi combe
1985a,b
98 Johnson and Flnley 1980
>806 Phlpps and Hoi combe
1985a,b
Jarvlnen and Tanner
1982
Hot combe et al . 1982
331.7 Phlpps and Hoi combe
1985a.b
Johnson and Flnley 1980
806 Phlpps and Hoi combe
1985a,b
Johnson and Flnley 1980
10 Phlpps and Hoi combe
1985a.b
-------
Table 1. (Continued)
Va
Species
Eastern oyster (larva),
Crassostrea vlrglnlca
Mysld (juvenile),
Mysldopsls bah la
Mysld (juvenile) ,
Mysldopsls bah la
Korean shrimp (adult),
Palaemon macrodacty 1 us
Korean shrimp (adult),
Palaemon macrodacty 1 us
Gulf toadtlsh (juvenile),
Opsanus beta
Sheepshead minnow
(juvenile),
Cyprlnodon varlegatus
Sheepshead minnow
(juvenile),
Cyprlnodon varlegatus
Mummlchog (adult),
Fundulus heteroclltus
Longnose kl 1 1 1 f 1 sh
( juvenl le) ,
Fundulus slml 1 Is
Cal Ifornla grunlon
(day 0 larva) ,
Leuresthes tenuls
California grunlon
(day 7 larva).
Method* Chemical**
S, U Technical
(92$)
S, U Technical
(92$)
F, M Technical
(92$)
S, U Chlorpyrlfos
(99$)
F, U Chlorpyrlfos
(99$)
R, M Technical
(92$)
S, U Technical
(92$)
f, M Technical
(92$)
S, U Technical
(99.5$)
F, M Technical
(92$)
S, U Technical
(92$)
S, U Technical
(92$)
Salinity
(a/kg)
SALTWATER
20
20
26.7
15
24
29-30
20
10.3
20-25
25.9
25
25
LC5O Species Mean
or EC5O Acute Value
(ii9/L)*«* (gg/L)
SPECIES
1,991 1,991
0.056
0.035 0.035
0.25
0.01 0.05
520 520
270
1 36 1 36
4.65 4.65
4.1 4.1
5.5
2.7
Reference
Borthwlck and Walsh 1981
Borthwlck and Walsh 1981
Schlmmel et al . 1983
Earnest 1970
Earnest 1970
Hansen et al . 1986
Borthwlck and Walsh 1981
Schlmmel et al . 1983
Thlrugnanam and Forgash
1977
Schlmmel et al . 1983
Borthwlck et al . 1985
Borthwlck et al . 1985
Leuresthes tenuls
-------
Fable 1. (Continued)
Species
Cal Horn la grunlon
(day 14 larva) ,
Leuresthes tenuls
California grunlon
(day 28 larva),
Leuresthes tenuls
California grunlon
(day 0 larva) ,
Leuresthes tenuls
Cal Ifornla qr union •
(day 7 larva) ,
Leuresthes tenuls
California grunlon
(day 14 larva) ,
Leuresthes tenuls
Cal Ifornla grunlon
(day 28 larva),
Leuresthes tenuls
Inland sllverslde
( juvenl le) ,
Men Id la bery 1 1 Ina
Atlantic sllverslde
(day 0 larva) ,
Men Id la men Id la
Atlantic sllverslde
(day 7 larva) ,
Men Id la men Id la
Atlantic sllverslde
(day 14 larva).
Men Id la men Id la
Method* Chemical**
S. U Technical
(92*)
S, U Technical
(92*)
F, M Technical
(92*)
F, M Technical
(92*)
F, M Technical
(92*)
•F, M Technical
(92*)
F, M ' Technical
(92*)
S, U Technical
(92*)
S, U Technical
(92*)
S, U Technical
(92*)
LC50 Species Mean
Salinity or EC 50 Acute Value
(g/kg) (fig/L)*** (ug/L)
25 1.8
25 2.6
25 1.0
25 1.0
25 1.0
25 1.3 1.068
5.0 4.2 4.2
20 4.5
20 2.8
20 2.4
Reference
Borthwlck et
Borthwlck et
Borthwlck et
Borthwlck et
Borthwlck et
Borthwlck et
Clark et al .
Borthwlck et
Borthwlck et
Borthwlck et
al . 1985
al. 1985
al . 1985
al. 1985
al . 1985
al . 1985
Manuscript
al . 1985
•
al . 1985
al . 1985
Atlantic sllverslde
(day 28 larva),
Men Id I a men Id I a
S, U Technical 20
(92*)
4.1
Borthwlck et al. 1985
-------
Table 1. (Continued)
VJ
V
Species
Atlantic sllverslde
(juvenile)
Men Id la men Id la
Atlantic sllverslde
(day 0 larva) ,
Men Id la men Id la
Atlantic sllverslde
(day 7 larva) ,
Men Id la men Id la
Atlantic sllverslde
(day 14 larva) ,
Men Id la men Id la
Atlantic sllverslde
(day 28 larva) ,
Men Id I a menldla
Tidewater sllverslde
(day 0 larva) ,
Menldla penlnsulae
Tidewater sllverslde
(day 7 larva) ,
Menldla penlnsulae
Tidewater sllverslde
(day 14 larva),
Menldla penlnsulae
Tidewater sllverslde
(day 28 larva),
Menldla penlnsulae
Tidewater sllverslde
(day 0 larva) ,
Menldla penlnsulae
Tidewater sllverslde
(day 7 1 arva) ,
Method* Chemical**
F, M Technical
(92*)
F, M Technical
(92$)
F, M Technical
(92$)
F, M Technical
(92$)
F, M Technical
(92* )
S, U Technical
(92%)
S, U Technical
(92?)
S, U Technical
(92$)
S, U Technical
(92$)
F, M Technical
(92$)
F, M Technical
(92$)
LC50 Species Mean
Salinity or EC50 Acute Value
(g/kg) dig/L)*** (ug/L)
24.3 1.7
20 0.5
20 1.0
20 1.1
20 3.0 1.229
20 4.2
20 2.0
20 1.8
20 3.9
20 1.0
20 0.5
Reference
Schlmmel et al . 1983
Borthwlck et al . (985
Borthwlck et al . 1985
Borthwlck et al . 1985
Borthwlck et al . 1985
Borthwlck et al . 1985
•
Borthwlck et al . 1985
Borthwlck et al . 1985
Borthwlck et al . 1985
Borthwlck et al . 1985
Borthwlck et al . 1985
Menldla penlnsulae
-------
Table 1. (Continued)
Vs)
Vw
Species
Tidewater sllverslde
(day 14 larva),
Men Id la penlnsulae
Tidewater sllverslde
(day 28 larva),
Men Id la penlnsulae
Tidewater sllverslde '
(juvenile) ,
Men Id la penlnsulae
Striped bass (juvenile),
Morone saxatl 1 Is
Striped mullet (juvenile),
Mugl 1 cephalus
* S = static; R = renewal
Method* Chemical**
F. M Technical
(92*)
F, M Technical
(921)
F, M Technical
(92?)
F, U Chlorpyrlfos
(99$)
F, M Technical
(92% )
; F = flow-through; U =
Salinity
(g/kg)
20
20
19.3
30
24.7
unmeasured;
LC50 Species Mean
or EC50 Acute Value
(i.g/L)*** (ng/L)
0.4
0.9
1.3 0.7479
0.58 0.58
5.4 5.4
M = measured.
Reference
Borthwlck et al . 1985
Borthwlck et al . 1985
Clark et al . Manuscript
Earnest 1970; Korn and
Earnest 1974
Schlmmel et al . 1983
** Percentage purity Is given In parentheses when available.
*** If the concentrations were not measured and the published results were not reported to be adjusted for purity, the
published results were multiplied by the purity If It was reported to be less than 91%.
**** The test material was dissolved from an encapsulated form of chlorpyr 1 tos.
-------
Table 2. Chronic Toxic Ity of Chlorpyrlfos to Aquatic Animals
V)
Species
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Mysld,
Mysldopsls bah la
Gul f toad fish,
Opsanus beta
Sheepshead minnow,
Cyprlnodon varlegatus
Sheepshead minnow,
Cyprlnodon varlegatus
Sheepshead minnow,
Cyprlnodon varlegatus
California grunlon,
Leuresthes tenuls
Inland sllverslde.
Men Id la bery 1 1 Ina
Atlantic sllverslde.
Men Id la menldla
Test*
ELS
ELS
LC
LC
ELS
ELS
ELS
ELS
ELS
ELS
ELS
Chemical**
Technical
(98.7$)
Encapsul ated
Encapsulated
Technical
(92$)
Techn leal
(92$)
Technical
(92$)
Technical
(92$)
Technical
(92$)
Techn leal
(92$)
Technical
(92$)
Techn leal
(92$)
Salinity Limits
(g/kg) (tig/L)***
FRESHWATER
-
t
t
SALTWATER
1 9-28
25-34
9-28
9-28
9-28
24.5-34
4-6
18-27
SPECIES
1.6-3.2
2.2-4.8
<0.12tf
SPECIES
0.002-0.004
1.4-3.7
1.7-3.0
1.7-3.0
1.7-3.0
.0 0.14-0.30
0.75-1.8
0.28-0.48
Chronic Value
(tig/L)
2.263
3.250
<0 . 1 2
0.0028
2.276
2.258
2.258
2.258
0.2049
1.162
0.3666
Reference
Jarvlnen
1982
Jarvlnen
1982
Jarvlnen
1983
and Tanner
and Tanner
et al .
McKenney et al. 1981
Hansen et al . 1986
Crlpe et al . Manuscript
Crlpe et
Crlpe et
Goodman
Goodman
Goodman
al . Manuscript
al . Manuscript
et al . 1985a
et al . 1985b
et al . 1985b
-------
Table 2. (Continued)
Species
Tidewater sliverslde.
Men Id la peninsulas
Salinity
Test» Chemical" (g/kg)
ELS Technical 18-25
(92$)
Limits Chronic Value
1,417
0.0028 12.50
2.276 228.5
2.258 60.23
2.258 60.23
0.2049 6.345
1.162 3.614
0.3666 4.637
0.5444 2.388
Menldla penlnsulae
-------
Table 3. Ranked Genus Mean Acute Values with Species Mean Acute-Chronic Ratios
lank*
15
14
13
12
11
10
9
8
7
6
5
4
Genus Mean
Acute Value
>806
>806
806
331.7
98
12.36
10
10
6
1.38
0.8
0.77
Species
FRESHWATER SPECIES
Snail,
Aplexa hypnorum
Goldfish,
Carasslus auratus
Channel catfish,
Ictalurus punctatus
Fathead minnow,
Plmephales promelas
Lake trout,
Salvellnus namaycush
Cutthroat trout,
Salmo clarkl
Rainbow trout,
Salmo galrdnerl
Stonef ly,
Pteronarcys callfornlca
Blueglll,
Lepomls macrochlrus
Crayfish,
Orconectes Immunls
Pyqmy backs* Immer ,
Neoplea strlola
Crawling water beetle,
Peltodytes sp.
Trlchoptera
Species Mean
Acute Value
>806
>806
806
331.7
98
18
8.485
10
10
6
1.38
0.8
0.77
Species Mean
Acute-Chron Ic
Ratio***
>,„,
LeptocecIdae sp.
-------
Table 3. (continued)
Rank*
3
2
1
to
X)
\/
8
7
6
5
Genus Mean Species Mean
Acute Value Acute Value
<»g/L) Species (ug/L)**
0.57 Stonefly,
Claasenla sabulosa
0.38 Stonefly,
i Pteronarcel la bad I a
0.1850 Amphlpod,
Gammarus fasclatus
Am phi pod,
Gammarus lacustrls
Amphtpod ,
Ganrimarus pseudol Imnaeus
SALTWATER SPECIES
1,991 Eastern oyster,
Crassostrea virgin lea
520 Gulf toadftsh,
Opsanus beta
136 Sheapshead minnow,
Cyprlnodon var legatus
5.4 Striped mul let,
Mug 11 cephalus
4.366 Mummlchog,
Fundulus heteroclltus
Longnose kl 1 1 If Ish,
Fundulus slml 1 Is
1.569 Inland sllverslde.
Men Id I a beryl 1 Ina
Atlantic sllverslde.
Men Id I a men Id la
Tidewater sllverslde,
0.57
0.38
0.32
0.11
0.18
1,991
520
136
5.4
4.65
4.1
4.2
1.229
0.7479
Species Mean
Acute-Chron Ic
Ratlo»*«
228.5
60.23
3.614
4.637
2.388
Men Id la men Id I a
-------
Table 3. (continued)
i
Rank*
4
3
2
1
Genus Mean
Acute Value
(tig/L)
1.068
0.58
0.05
0.035
Species
California grunlon,
Leuresthes tenuts
Striped bass,
Morone saxatl Us
Korean shrimp,
Palaemon macrodacty lus
Mysld,
Mysldopsls bah la
Species Mean
Acute Value
-------
Table 4. ToxicIty of Chlorpyrltos to Aquatic Plants
Species
Chemical*
Duration
(days)
Salinity
(g/kg)
Effect
Result
(ug/L>««
Reference
SALTWATER SPECIES
Golden-brown alga,
1 sochrys 1 s ga 1 bana
Diatom,
Skeletonema costatum
Diatom,
Thalassloslra pseudonana
Tachn leal
(92%)
Technical
(92?)
Techn leal
(92*)
4
4
4
30
30
30
EC50 (popla-
1 at Ion growth)
EC50 (popula-
1 at Ion growth)
EC50 (popula-
1 at Ion growth)
138
297.8**"
148
Borthwlck and
1981
Borthwlck and
1981
Borthwlck and
1981
Walsh
Walsh
Walsh
* Percentage purity Is given In parentheses when available.
** If the concentrations were not measured and the published results were not reported to be adjusted for purity,
the published results were multiplied by the purity If It was reported to be less than 97?.
*** Geometric mean of five values.
-------
Table 5. Bloconcentratlon of Chlorpyrlfos by Aquatic Organisms
Species .
Concentration Duration
Chemical* In Water (ng/L)"* (days) Tissue BCF or BAF**« Reference
Fathead minnow,
Plmephales promelas
Gulf toadflsh,
Opsanus beta
Sheepshead minnow,
Cyprlnodon varlegatus
California grunton,
Leuresthes tenuls
Cal Ifornla grunlon,
Leuresthes tenuls
Inland sllverslde,
Men Id I a beryl Una
Tidewater sllverslde.
Men Id la penlnsulae
FRESHWATER SPECIES
Encapsulated* 0.12-2.68 60
SALTWATER SPECIES
Technical 1.4-150 49
(92*)
Technical 0.41 28
(92*) 0.78
Technical 0.14-0.63 35
(92*)
Technical 0.28-1.3 • 26
(92?)
Technical 0.18-1.8 28
(92*)
Technical 0.093-0.38 28
(92*)
Whole
body
Whole
body
Whole
body
(n=6)
Whole
body
(n=3)
Whole
body
(n=3)
Whole
body
(n=4)
Whole
body
(n=3)
1,673
100-
5,100
via"
757"
(from ELS
test)
120^
( f ran fry
test)
186ft
456ft
Jarv Inen et al . 1983
Han sen et al „ 1986
Crlpe et al . Manuscript
Goodman et al . 1985 a
Goodman et al . 1985a
Goodman et al . 1985b
Goodman et al . 1985b
* Percentage purity Is given In parentheses when available.
** Measured concentration of Chlorpyrlfos.
*** Bloconcentratlon factors (BCFs) and bloaccumulatlon factors (BAFs) are based on measured concentrations of Chlorpyrlfos In water
and tissue.
* The test material was dissolved from an encapsulated form of Chlorpyrlfos.
* Geometric mean of values from the listed concentrations In water.
-------
Table 6. Other Data on Effects of Chlorpyrlfos on Aquatic Organisms
Species
Chemical*
Duration
Effect
Result
(M9 A.)** Reference
FRESHWATER SPECIES
Diatoms,
Unidentified
Planar Jan,
Dugesla dorotocephala
Cladoceran,
Daphnla sp.
Amphlpod,
Hyalel la azteca
Mayfly,
Ephemeral la sp.
Pygmy backswlmmer,
Neoplea strlola
Giant water bug (adult),
Belostoma sp.
Predaceous diving beetle
(adult),
Hygrotus sp.
Predaceous diving beetle
(adult),
Laccophllus dec Ip lens
Predaceous diving beetle
(adult),
T hermonectus bas 1 1 1 ar 1 s
Water scavenger beetle
(adult),
Berosus styllferus
10 days
Chlorpyrlfos 24 hr
Encapsulated*** 4 hr
Encapsulated*** 24 hr
Encapsulated*** 72 hr
Encapsulated*** 144 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
.Reduced
growth
None
LC50
LC50
LC50
LC50
LC50
LC50 .
LC50
LC50
LC50
400 Rogers and Miller 19
4.0 Levy and Miller 1978
0.88 Slefert et al . 1984
1.28 Slefert et al . 1984
0.33 Slefert et al . 1984
0.97 Slefert et al . 1984
15 Ahmed 1976
40 Ahmed 1976
4.6 Ahmed 1976
6 Ahmed 1 976
9 Ahmed 1976
Water scavenger beetle
(larva),
Hydrophllus triangular Is
Technical
24 hr
LC50
20
Ahmed 1976
-------
Table 6. (continued)
Species
Water scavenger beetle
(adult),
Hydrophllus triangular Is
Water scavenger beetle
(larva),
Troplsternus lateral Is
Water scavenger beetle
(adult),
Troplsternus lateral Is
Mosquito (3rd and 4th
Instar),
Aedes aegyptl
Mosquito (2nd Instar),
Aedes aegyptl
Mosquito (4th Instar),
Aedes aegyptl
Mosquito (4th Instar),
Aedes cantans
Mosquito (4th Instar),
Aedes communls
Mosquito (4th Instar) ,
Aedes excruclans
Mosquito (4th Instar) ,
Aedes punctor
Mosquito (4th Instar),
Aedes stlctlcus
Mosquito (4th Instar),
Aedes vexans
Mosquito ( larva) ,
Chemical*
Techn leal
Technical
Techn leal
Techn leal
Technical
(96$)
Techn leal
(96$)
Technical
Techn leal
Techn leal
Techn leal
Techn leal
Techn leal
Techn leal
Duration
24 hr
24 hr
24 hr
18 hr
24 hr
24 hr
24 hr
24 hr
24 hr
24 hr
24 hr
24 hr
24 hr
Effect
LC50
LC50
LC5O
LT50
LC50
LC50
LC50
LC50
LC50
LC50
LC50
LC50
LC50
Result
(ng/L)** Reference
30
52
10
0.0011
0.0014
1.1
3.5
3.3
2.7
0.5
1.0
3
Ahmed 1976
Ahmed 1976
Ahmed 1976
Verma and Rahman 1984
Sal eh at al. 1981
Sal eh at al. 1981
Rettlch 1977
Rettlch 1977
Rettlch 1977
Rettlch 1977
Rettlch 1977
Rettlch 1977
Ahmed 1976
Anopheles freebornl
-------
Table 6. (continued)
Result
Vw
Species
Mosquito (4th Instar) ,
Anopheles freebornl
Mosquito (3rd and 4th
Instar) ,
Anopheles Stephens!
Phantom midge.
Chaoborus sp.
Mosquito (4th Instar),
Culex plplens
Mosquito (2nd Instar;
DDT susceptible) ,
Culex plplens
Mosquito (4th Instar;
DDT susceptible) ,
Culex plplens
Mosquito (4th Instar) ,
Culex plplens
Mosquito (4th Instar) ,
Culex plplens
Mosquito (3rd and 4th
Chemical*
Technical
Technical
Encapsulated***
Technical
(99*
Technical
(96*)
Technical
(96*)
Techn leal
Techn leal
Techn leal
Duration
24 hr
6.5 hr
18 hr
42 hr
114 hr
24 hr
24 hr
24 hr
24 hr
24 hr
5 hr
Effect
LC50
LT50
LC50
LC50
LC50
EC50
LC50
LC50
LC50
LC50
LT50
(n9/L)**
1.3
0.9
2.5
.2
.2
.9
.3
.2
2.8
3.3
7.0
25
2.36
1.29
0.85
0.46
0.0022
0.0052
1.2
1.6
10
Reference
Wocneldorf et al . 1970
Verma and Rahman 1984
Slefert et al . 1984
Nelson et al. 1979
Sal eh et al . 1981
Sal eh et al . 1981
Rettlch 1977
Rettlch 1977
Verma and Rahman 1984
Instar),
Culex qulnquefasclatus
-------
Table 6. (continued)
Species
Chemical*
Duration Effect
Result
(pg/L)** Reference
Mosquito (4th Instar),
Culex restuans
Mosquito ( larva) ,
Culex tarsal Is
Mosquito (4th Instar),
Cut Iseta annul ata
Midge (4th Instar) ,
Chlronomus sp.
Midge (4th Instar),
Chlronomus decor us
Midge (4th Instar) ,
Chlronomus utahensls
Midge (4th Instar) ,
Crlcotopus decorus
Midge (4th Instar),
Dlcrotendlpes callfornlcus
Midge (4th Instar) ,
Goe 1 d I ch 1 ronomus
holoprasslnus
Midge (4th Instar) ,
Prod ad! us spp.
Midge (4th Instar),
Tanypus grodhausl
Midge (4th Instar) ,
Tanypus grodhausl
Midge (4th Instar),
Tanygus grodhausl
Rainbow trout,
Salmo galrdner)
Technical 24 hr
(992)
Technical
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 24 hr
Technical 96 hr
LC50 0.41
LC50 2
LC50 3.5
LC50 0 .42
LC50 7.0
LC50 1 .2
LC50 1 ,470
LC50 40.0
LC50 0.97
LC50 0.5
LC5O 29.0
LC5O 0.5
LC50 5.7
LC50 (7.2°C) 15
(1.6°C) 51
He (son et al . 1979
Ahmed 1976
Rettlch 1977
Mul la and Khasawlnah 1969
Al 1 and Mul la 1978a
Al 1 and Mul la 1978a
Al 1 and Mul la 1980
Al 1 and Mul la 1980
Mul la and Khasawlnah 1969
Al 1 and Mull a 1978a
Al 1 and Mul la 1980
Mul la and Khasawlnah 1969
Mul la and Khasawlnah 1969
Macak et al . 1969
-------
Table 6. (continued)
Species
Atlantic salmon (juvenile),
Salmo salar
Golden shiner,
Notemlgonus crysoleucas
Golden shiner,
Notemlgonus crysoleucas
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Fathead minnow,
Plmephales promelas
Mosqultof 1 sh,
Gambusla afflnls
Mosqultof Ish
(DDT susceptible),
Gambusla afflnls
Mosqultof Ish
(DDT resistant),
Gambusla afflnls
Mosqultof Ish,
Gambusla afflnls
Mosqultof Ish (adult) ,
Gambusla afflnls
Mosqultof Ish,
Gambusla afflnls
Chemical* Duration
Technical 24 hr
(>95$)
Technical 36 hr
(99$)
Technical 36 hr
199%)
Technical**** 96 hr
Encapsulated*** 96 hr
Encapsu- 96 hr
lated***, ***«
Chlorpyrlfos
Technical 48 hr
Technical 48 hr
Chlorpyrlfos 24 hr
Technical 72 hr
Technical 36 hr
(99*)
Effect
Temperature
selection
LC50
LC50
LC50
LC50
LC50
Avoidance
LC50
LC50
Decreased
thermal tolerance
LC50
LC50
Result
100
45
35
150
130
280
100
1,018
1,291
5
0.22
0.20
0.20
0.19
0.20
0.20
230
215
Reference
Peterson 1976
Ferguson et a
Ferguson et a
Jarvlnen and
Jarvlnen and
Jarvlnen and
Hansen et al .
Cul ley and Fei
Cul ley and Fei
Johnson 1978a
Ahmed 1976
Ferguson et a
-------
Table 6. (continued)
Species
MosqultofIsh,
Gambus la afflnls
Guppy,
Poecllla ret leu I ata
Green sunflsh,
Lepqmls cyanellus
Species
Green alga,
Chlorococcum sp.
Diatom,
Skeletonema costatum
Diatom,
Amphlprora sp.
Dlnoflagellate,
Gonyaulax sp.
Benthlc macrofauna
Result
Benthlc macrofauna
Chemical*
Chlorpyr 1 tos
Technical
Technical
(99$)
Chemical*
Chlorpyr 1 f os
Technical
(92%)
Chlorpyr If os
Chlorpyrl tos
Techn leal
(92$)
Technical
(92?)
Duration
24 hr
24 hr
36 hr
Salinity
(q/Kq)
27
30
27
27
26.5
(14.5-34.0)
27.5
(18.0-32.5)
Effect
-------
Table 6. (continued)
Species
Eastern oyster
( juvenl 1 e) ,
Crassostrea vlrglnlca
Eastern oyster
(juvenl le) ,
Crassostrea vlrglnlca
Brown shr Imp
(juvenl le) ,
Penaeus aztecus
Pink shrimp
(juvenl le) ,
Penaeus duorarum
Grass shrimp
(juvenile) ,
Palaemonetes puglo
Grass shrimp (adult),
Palaemonetes puqlo
Blue crab (juvenile),
Calllnectes sapldus
Atlantic salmon
(juvenl le) ,
Sal mo salar
Sheepshead minnow
(juvenl le) ,
Cyprlnodon varlegatus
Sheepshead minnow
(adult),
Cypr Inodon varlegatus
Sheepshead minnow
( juven lie),
Cyprlnodon varlegatus
Chemical*
Chlorpyrl fos
(99*)
Chlorpyrl fos
(99*)
Chlorpyrl fos
(99*)
Chlorpyrl fos
(99*)
Chlorpyrl fos
(99*)
Chlorpyrl fos
(99*)
Chlorpyrl fos
(99*)
Chlorpyrl fos
(>95*)
Techn leal
(92*)
Chlorpyrl fos
(99*)
Chlorpyr Ifos
(99*)
Salinity Result
ig/kg) Duration Effect ((sgA.)"*
24 96 hr EC50 (shel 1 270
deposition)
28 96 hr EC50 (shell 34
deposition)
26 48 hr EC50 (mortal Ity 0.20
and loss of
equl 1 Ibrlum)
26 48 hr EC50 2.4
26 48 hr EC50 (mortality 1.5
and loss of
equl 1 Ibrlum)
20 1 hr No avoidance 0.01-1.0
of pesticide
20 -48 hr EC50 5.2
24 hr Altered preferred 100-250
temperature
9-30 28 days BCF = 42-660 0.41-52
(low food);
69-1,000 (med.
food); 120-1,830
(high food)
20 1 hr Avoidance of 100-250
pesticide
24 48 hr LC50 1,000
Reference
U.S. Bureau of Commercial
Fisheries 1965; Lowe et al
1970
U.S. Bureau of Commercial
Fisheries 1967
U.S. Bureau of Commercial
Fisheries 1965; Lowe et al
1970
U.S. Bureau of Commercial
Fisheries 1967
U.S. Bureau of Commercial
Fisheries 1967)
Hansen et al. 1973
U.S. Bureau of Commercial
Fisheries 1967
Peterson 1976
Crlpe et al . Manuscript
Hansen 1969,1970
U.S. Bureau of Commercial
Fisheries 1967
-------
Table 6. (continued)
Species
Mummlchog (adult),
Fundulus heteroclltus
Longnose kllllflsh
(juvenile) ,
Fundulus slml 1 Is
California gr union,
Leuresthes tenuls
Spot ( juvenl le),
Lelostomus xanthurus
* Percentage purity
*• If tho rnnr.antrat'
Chemical*
Technical
(99.5*)
Chlorpyr I fos
(99*)
Technical
(92*)
Chlorpyr I fos
(99*)
Salinity
(g/kg) Duration
20-25 24 hr
24 48 hr
24.5- 26 days
31.5
26 48 hr
Result
Effect (Mg/L)"»
100* Inhibition >2.1
of acetylchol In-
est erase activity
In brain
LC50 3.2
Significantly 0.62
reduced growth
of fry
LC50 7
Reference*
Thlrugnanam and Forgash
1977
U.S. Bureau of Commercial
Fisheries 1967; Lowe et al .
1970
Goodman et al . 19B5a
U.S. Bureau of Commercial
Fisheries 1965
Is given In parentheses when available.
[nrr; affa not measured and the oubllshed results were not reoorted to be adjusted for ourltv. the
published results were multiplied by the purity If It was reported to be less than 97*.
*** The test material was dissolved from an encapsulated form of chlorpyr I fos.
**** Anarl \\ weeks.
-------
REFERENCES
Ahmed, W. 1976. The effectiveness of predators of rice field mosquitoes
in relation to pesticide use in rice culture. Ph.D. thesis. University of
California-Davis. Available from University Microfilms, Ann Arbor, MI.
Order No. 77-6323.
All, A. 1981. Laboratory evaluation of organophosphate and new synthetic
pyrethroid insecticides against pestiferous chironomid midges of central
Florida. Mosq. News 41:157-161.
Ali, A. and M.S. Mulla. 1976. Insecticidal control of chironomid midges
in the.Santa Ana River water system, Orange County, California. J. Econ.
Entomol, 69:509-513. .
Ali, A. and M.S. Mulla. 1977. The IGR diflubenzuron and organophosphorus
insecticides against nuisance midges in man-made residential-recreational
lakes. J. Econ. Entomol. 70:571-577.
Ali, A. and M.S. Mulla. 1978a. Declining field efficacy of chlorpyrifos
against chironomid midges and laboratory evaluation of substitute
larvicides. J. Econ. Entomol. 71:778-782.
Ali, A,, and M.S. Mulla. 1978b. Effects of chironomid larvicides and
diflubenzuron on nontarget invertebrates in residential-recreational
lakes. Environ. Entomol. 7:21-27.
Ali, A. and M.S. Mulla. 1980. Activity of organophosphate and synthetic
pyrethroid insecticides against pestiferous midges in some southern
California flood control channels. Mosq. News 40:593-597.
39
-------
Al-Khatib, Z.I. 1985. Isolation of an organophosphate susceptible strain
of Culex quinquefasciatus from a resistant field population by discrimination
against esterase-2-phenotypes. J. Am. Mosq. Control Assoc. 1:105-107.
Atallah, Y.H. and M.M. Ishak. 1971. Toxicity of some commonly used
insecticides to the snail Biomphalaria alexandrina, intermediate host of
Schistoma monsoni in Egypt. Z. Angew Entomol. 69:102-106.
Axtell, R.C., J.C. Dukes and T.D. Edwards. 1979. Field tests of
diflubenzuron, methoprene, Flit MLO and chlorpyrifos for the control of
Aedes taeniorhynchus larvae in diked dredged spoil areas. Mosq. News 39:
•
520-527.
Barton, L.C. 1970. The effect of sublethal concentrations of Dursban on
immature Culex pipiens quinquefasciatus. Entomological Special Study No.
31-004-70/71. U.S. Army Environmental Hygiene Agency, Edgewood Arsenal, MD.
Best, D.W. 1969. Dursban effective for mosquito control in creek bottoms
and duck ponds. Proc. Pap. Annu. Conf. Calif. Mosq. Control Assoc.
37:133-134.
Birmingham, B.C. and B. Colman. 1977. The effect of two organophosphate
insecticides on the growth of freshwater algae. Can. J. Bo.t. 55:1453-
1456.
Boike, A.H. and C.B. Rathburn. 1969. Laboratory tests of the susceptibility
of mosquito larvae to insecticides in Florida, 1968. Mosq. News 29:392-395.
Borthwick, P.W. and G.E. Walsh. 1981. Initial toxicological assessment of
Ambush, Bolero, Bux, Dursban, Fentrifanil, Larvin, and Pydrin: Static acute
40
-------
toxicity tests with selected estuarine algae, invertebrates and fish.
EPA 600/4-81-076. National Technical Information Service, Springfield, VA.
Borthwick, P.W., J.M. Patrick, Jr., and D.P. Middaugh. 1985. Comparative
acute sensitivities of early life stages of atherinid fishes to chlorpyrifos
and thiobencarb. Arch. Environ. Contain. Toxicol. 14:465-473.
Braun, H.E. and R. Frank. 1980. Organochlorine and organophosphorus
insecticides: Their use in eleven agricultural watersheds and their loss
to stream waters in southern Ontario, Canada, 1975-1977. Sci. Total.
Environ. 15:169-192.
Brown, J.R. and L.Y; Chow. 1975. The effect of Dursban on :micro-flora in
non-saline waters. In: Environmental quality and safety supplement, Vol.
III. Pesticides. Coulston, P. Fredrick and F. Korte (Eds.). International
Union Pure Applied Chemistry, pp. 774-779.
Brown, J.R., L.Y. Chow and C.B. Deng. 1976. The effect of Dursban upon
fresh water phytoplankton. Bull. Environ. Contam. Toxicol. 15:437-444.
Butcher, J., M. Boyer and C.D. Fowle. 1975. Impact of Dursban and Abate
on microbial numbers and some chemical properties of standing ponds.
Water 'Pollut. Res. Can. 10:33-41.
Butcher, J.E., M.G. Boyer and C.D. Fowle. 1977. Some changes in pond
chemistry and photosynthetic activity following treatment with increasing
concentrations of chlorpyrifos. Bull. Environ. Contam. Toxicol. 17:752-758.
Campbell, B.C. and R.F. Denno. 1976. The effect of temephos and chlorpyrifos
on the aquatic insect community of a New Jersey salt marsh. Environ.
Entomol. 5:477-483.
41
-------
Carter, F.L. and J.B. Graves. 1972. Measuring effects of insecticides on
aquatic animals. La. Agric. 16:14-15.
Chang, V.C. and W.H. Lange. 1967. Laboratory and field evaluations of
selecting pesticides for control of the red crayfish in California rice
fields. J. Econ. Entomol. 60:473-477.
Chatterji, S.M., J.P. Kulshroshtha and S. Rajamani. 1979. Some promising
insecticides for the control of the rice gall midge, Orseolia oryzae. J.
Entomol. Res. 3:168-171.
Clark, J.R., D. DeVault, R.J. Bowden and J.A. Weishaar. 1984. Contaminant
analysis of fillets from Great Lakes coho salmon. 1980. J. Great Lakes
Res. 10:38-47.
Clark, J.R., J.M. Patrick, Jr., D.P. Middaugh and J.C. Moore. Manuscript.
Relative sensitivity of six estuarine fishes to carbophenothion,
chlorpyrifos, and fenvalerate. U.S. EPA, Environmental Research Laboratory,
Gulf Breeze, FL.
Cooney, J.C. and E. Pickard. 1974. Field tests with Abate and Dursban
insecticides for control of floodwater mosquitoes in the Tennessee Valley
region. Mosq. News 34:12-22.
Gripe, G.M., D.J. Hansen, S.F. Macauley and J. Forester. Manuscript.
Effects of diet quantity on sheepshead minnows (Cyprinodon variegatus)
during early life-stage exposures to chlorpyrifos. U.S. EPA, Environmental
Research Laboratory, Gulf Breeze, FL.
42
-------
Culley, D.D. and D.E. Gerguson. 1969. Patterns of insecticide resistance
in the tnosquitofish, Gambusia affinis. J. Fish. Res. Board Can. 26:2395-2401.
Darwazeh, H.A. and M.S. Mulla. 1974. Toxicity of herbicides and mosquito
larvicides to the mosquitofish Gambusia affinis. Mosq. News 34:214-219.
Davey, R.B., M.V. Meisch and F.L. Carter. 1976. Toxicity of five rice
field pesticides to the mosquitofish, Gambusia affinis, and green sunfish,
Lepomis cyane1lus, under laboratory and field conditions in Arkansas.
Environ. Entomol. 5:1053-1056.
Dixon, R.D. and R.A. Brust. 1971. Fieldt testing of insecticides used in
mosquito control, and a description of the bioassay technique used in
temporary pools. J. Econ. Entomol. 64:11-14.
Earnest, R. 1970. Effects of pesticides on aquatic animals in the estuarine
and marine environment. Progress in Sport Fisheries Research 1970. Resource
Publication 106. U.S. Superintendent of Documents, U.S. Government Printing
Office, Washington, DC. 20402. pp. 10-13.
El-Refai, A., F.A. Fahmy, M.F. Abdel-Lateef and A-K Imam. 1976. Toxicity
of three insecticides to two species of fish. Int. Pest Control 18:4-8.
Evans, E.S. 1977. Field evaluation of the extended mosquito larvicidal
activity of a controlled-release chlorpyrifos polymer in a woodland pool
habitat, March 1974-October 1976. Entomological Special Study No. 44-0364-77
U.S. Army Environmental Hygiene Agency, Aberdeen Proving Ground, MD.
Evans, E.S., J.H. Nelson, N.E. Pennington and W.W. Young. 1975. Larvicidal
effectiveness of a controlled-release formulation of chlorpyrifos in a
woodland pool habitat. Mosq. News 35:343-350.
43
-------
Federle, P.F. and W.J. Collins. 1976. Insecticide toxicity to three
insects from Ohio ponds. Ohio J. Sci. 76:19-24.
Ferguson, D.E., D.T. Gardner and A.L. Lindley. 1966. Toxicity of Dursban
to three species of fish. Mosq. News 26:80-82.
Fitzpatrick, G. and D.J. Sutherland. 1978. Effects of the organophosphorus
insecticides temephos (Abate) and chlorpyrifos (Dursban) on populations
of the salt-marsh snail, Melampus bidentatus. Mar. Biol. 46:23-28.
Frank, A.M. and R.D. Sjogren. 1978. Effects of temephos and chlorpyrifos
on Crustacea. Mosq. News 38:138i-139
Gillies, P.A., D.J. Womeldorf, E.P. Zboray, and K.E. White. 1974. Insecticide
susceptibility of mosquitoes in California: Status of organophosphorus
resistance in larval Aedes nigromaculis and Culex tarsalis through 1973.
Proc. Pap. Annu. Conf. Calif. Mosq. Control Assoc. 42:107-112.
Goodman, L.R., D.J. Hansen, G.M. Gripe, D.P. Middaugh and J.C. Moore.
1985a. A new early life-stage toxicity test using the California grunion
(Leuresthes tenuis) and results with chlorpyrifos. Ecotoxicol. Environ.
Safety 10:12-21.
Goodman, L.R., D.J. Hansen, D.P. Middaugh, G.M. Gripe and J.C. Moore.
1985b. Method for early life-stage toxicity tests using three atherinid
fishes and results with chlorpyrifos. In: Aquatic toxicology and hazard
assessment: 7th symposium. R.D, Cardwell, R. Purdy and R.C. Bahner (Eds.).
ASTM STP 854. American Society for Testing and Materials, Philadelphia,
PA. pp. 145-154.
44
-------
Gray, H.E. 1965. Dursban, a new organophosphorus insecticide. Down Earth
21:26-27.
Hansen, D.J. 1969. Avoidance of pesticide by untrained sheepshead minnows.
Trans. Am. Fish. Soc. 98:426-429.
Hansen, D.J. 1970. Behavior of estuarine organisms. Progress report.
Contribution No, 98:23-28. Bureau of Commercial Fisheries Center for
Estuarine and Menhaden Research, Pesticide Field Station, Gulf Breeze, FL.
Hansen, D.J., L.R. Goodman, G.M. Gripe and S.F. Macauley. 1986. Early
life-stage toxicity test methods for gulf toadfish (Opsanus beta) and
results using chlorpyrifos. Ecotoxicol. Environ. Safety. ll:xxx-yyy.
•
Hansen, D.J., E. Mattews, S.L. Nali and D.P. Dumas. 1972. Avoidance of
pesticides by untrained mosquitofish, Gambusia affinis. Bull. Environ.
Contain.. Toxicol. 8:46-51.
Hansen, D.J., S.C. Schimmel and J.M. Keltner, Jr. 1973. Avoidance of
pesticides by grass shrimp (Palaemonetes pugio). Bull. Environ. Contain.
Toxicol. 9:129-133.
Hazeleur, W.C. 1971. Use of Dursban for mosquito control in log ponds in
the Shasta Mosquito Abatement District. Proc. Pap. Annu. Conf. Calif.
Mosq. Control Assoc. 39:47.
Helson, B.V., G.A. Surgeoner and W.E. Ralley. 1979. Susceptibility of
Culex spp. and Aedes spp. larvae (Diptera: Culicida«) to temephos and
chlorpyrifos in southern Ontario. Proc. Entomol. Soc. Ont. 110: 79-83.
45
-------
Herin, R.A., J.E. Suggs, E.M. Lores, L.T. Heiderscheit, J.D. Farmer and
D. Prather. 1978. Correlation of salt gland function with levels of
chlorpyrifos in the feed of mallard ducklings. Pestic. Biochem. Physiol.
9:157-163.
Holcombe, G.W., G.L. Phipps and O.K. Tanner. 1982. The acute toxicity of
kelthane, Dursban, disulfoton, pydrin, and permethrin to fathead minnows
Pimephales promelas and rainbow trout Salmo gairdneri. Environ. Pollut.
(Ser. A.) 29:167-178.
Hoy, J.B., E.E. Kauffman, and A.G. O'Berg. 1972. A large-scale field test
of Gambusia affinis and chlorpyrifos for mosquito control. Mosq. News
32:161-171.
Hughes, D.N. 1977. The effects of three organophosphorus insecticides on
ZQOplankton and other invertebrates in natural and artificial ponds. M.S.
dissertation. York University, Toronto, Canada.
Hughes, D.N., M.G. Boyer, M.H. Papst, C.D. Fowle, G.A. Rees and P. Baulu.
1980. Persistence of three organophosphorus insecticides in artificial
ponds and some biological implications. Arch. Environ. Contam. Toxicol.
9:269-279.
Hurlbert, S.H. 1969. The impact of Dursban on pond ecosystems. Proc. Pap.
Annu. Conf. Calif. Mosq. Control Assoc. 37:8.
Hurlbert, S.H., M.S. Mulla, J.O. Keith, W.E. Westlake and M.E. Dusch.
1970. Biological effects and persistence of Dursban in freshwater ponds.
J. Econ. Entomol. 63:43-52.
46
-------
Hurlbert, S.H., M.S. Mulla and H.R. Wilson. 1972. Effects of an
organophosphorus insecticide on the phytoplankton, zooplankton, and insect
populations of freshwater ponds. Ecol. Monogr. 42:269-299.
Jamnback, H. 1969. Field tests with larvicides other than DDT for control
of blackfly (Diptera: Simuliidae) in New York. Bull. WHO 40:635-638.
Jamnback, H. and J. Frempong-Boadu. 1966, Testing blackfly larvicides in
the laboratory and in streams. Bull. WHO 34:405-421.
Jarvinen, A.W. and O.K. Tanner. 1982. Toxicity of selected controlled
•
release and corresponding unformulated technical grade pesticides to the
fathead minnow Pimephales promelas. Environ. Pollut. (Ser. A.) 27:179-195.
Jarvinen, A.W., B.R. Nordling and M.E. Henry. 1983. Chronic toxicity of
Dursban (chlorpyrifos) to the fathead minnow (Pimephales promelas) and
the resultant acetycholinesterase inhibition. Ecotoxicol. Environ. Safety
7:423-434.
Johnson, C.R. 1977a. The effects of field applied rates of five
organophosphorus insecticides on thermal tolerance, orientation, and
survival in Gambusia affinis affinis. Proc. Pap. Annu. Conf. Calif. Mosq.
Vector Control Assoc. 45:56-58.
Johnson, C.R. 1977b. The effect of exposure to the organophosphorus
insecticide chlorpyrifos on the feeding rate in the mosquitofish, Gambusia
af finis. Proc. Pap. Annu. Conf. Calif. Mosq. Vector Control Assoc. 45:69-70.
Johnson, C.R. 1978a. The effects of sublethal concentrations of five
organophosphorus insecticides on temperature tolerance, reflexes, and
orientation in Gambusia affinis affinis. Zool. J. Linn. Soc. 64:63-70.
47
-------
Johnson, C.R. 1978b. The effect of five organophosphorus insectides on
survival and temperature tolerance in the copepod, Macrocyclops albidus.
Zool. J. Linn. Soc. 64:59-62.
Johnson, W.W. and M.T. Finley. 1980. Handbook of acute toxicity of
chemicals to fish and aquatic invertebrates. Research Publication 137.
U.S. Fish and Wildlife Service, Columbia, MO. p. 21.
Jones, G.E., D.F. Carroll, and W. Wills. 1976. Susceptibility of Pennsylvania
mosquito larvae to Abate, Dursban and Baytex. Proc. Annu. Meet. N.J. Mosq.
Extern. Assoc. 63:161-164.
Karnak, R.E. and W.J. Collins. 1974. The susceptibility of selected
insecticides and acetylcholinesterase activity in a laboratory colony of
midge larvae, Chironomus tentans (Diptera: Chironomidae). Bull. Environ.
Contain. Toxicol. 12:62-69.
Kenaga, E.E. and C.A. Goring. 1980. Relationship between water solubility,
soil sorption, octanol-water partitioning, and concentration of chemicals
in biota. In: Aquatic toxicology. Eaton, J.G., P.R. Parrish and A.C.
Hendricks (Eds.). ASTM STP 707. American Society for" Testing and Materials,
Philadelphia, PA. pp. 78-115.
Kenaga, E.E., W.K. Whitney, J.L. Hardy and A.E. Doty. 1965. Laboratory
tests with Dursban insecticide. J. Econ. Entomol. 58:1043-1050.
Khudairi, S.Y. and E. Ruber. 1974. Survival and reproduction of ostracods
as affected by pesticides and temperature. J. Econ. Entomol. 67:22-24.
Korn, S. and R. Earnest. 1974. Acute toxicity of 20 insecticides to a
striped bass (Morone saxatilis). Calif. Fish Game 60:128-131.
48
-------
Ledieu, M.S. 1978. Candidate insecticides for the control of larvae of
Mamestra brassicae (Lepidoptera) (Noctuidae). Ann. Appl. Biol. 88:251-255.
Lembright, H.W. 1968. Dosage studies with low volume applications of
Dursban insecticide. Down Earth 24:16-19.
Levy, R. and T.W. Miller, Jr. 1978. Tolerance of the planarian Dugesia
dorotocephala to high concentrations of pesticides and growth hormones.
Entomophaga 23:31-34.
Linn, J.D. 1968. Effects of low volume aerial spraying of Dursban and
fenthion on fish. Down Earth 24:28-30.
•
Lowe, J.T., P.O. Wilson and R.B. Davison. 1970. Laboratory bioassays. In:
Progress report for fiscal year 1969. Circular 335. U.S. Fish and Wildlife
Service, Pesticide Field Station, Gulf Breeze, FL.
Macalady, D.L. and N.L. Wolfe. 1985. Effects of sediment sorption and
abiotic hydrolyses. 1. Organophosphorothioate esters. J. Agric. Food
Chem. 33:167-173.
Macek, K.J., C. Hutchinson and O.B. Cope. 1969. The effects of temperature
on the susceptibility of bluegills and rainbow trout to selected pesticides,
Bull. Environ. Contain. Toxicol. 4:174-183.
Macek, K.J., D.F. Walsh, J.W. Hogan and D.D. Holz. 1972. Toxicity of the
insecticide Dursban to fish and aquatic invertebrates in ponds. Trans.
Am. Fish. Soc. 101:420-427.
Maly, M. and E. Ruber. 1983. Effects of pesticides on pure and mixed
species cultures of salt marsh pool algae. Bull. Environ. Contam. Toxicol.
30:464-472.
49
-------
Marganian, V.M. and W.J. Wall, Jr. 1972. Dursban and diazinon residues in
biota following treatment of intertidal plots on Cape Cod - 1967-69.
Pestic. Monit. J. 6:160-165.
Marshall, W.K. and J.R. Roberts. 1978. Ecotoxicology of chlorpyrifos.
NRCC 16079. National Research Council of Canada, Ottawa, Ontario, Canada.
McKenney, C., Jr., E. Matthews and D. Lawrence. 1981. Mysid life-cycle
tests. Progress Report, FY81. Experimental Environments Branch. U.S. EPA,
Environmental Research Laboratory, Gulf Breeze, FL.
McNeill, J.C., W.O. Miller and C.M. Wleczyk. 1968. Evaluation of Dursban
. as a larvicide in septic ditches. Mosq. News. 28:160-161.
Menzie, C.M. 1969. Metabolism of pesticides. Special Scientific Report -
Wildlife No. 127. Bureau of Sport Fisheries and Wildlife, Washington, DC.
Metcalf, R.L. 1974. A laboratory model ecosystem to evaluate compounds
producing biological magnification. In: Essays in toxicology-V. Hayes,
W.J. (Ed.). Academic Press, New York, NY. pp. 17-38.
Meyer, F.P. 1981. Influences of contaminants on toxicity of lampricides.
Quarterly report of progress, April-June, 1981. U.S. Fish and Wildlife Service,
National Fisheries Research Laboratory, LaCrosse, WI and S.E. Fish Control
Laboratory, Warm Springs, GA.
Micks, D.W. and D. Rougeau. 1977. Organophosphorus tolerance in Culex
quinquefasciatus in Texas. Mosq. News 37:233-239.
Miller, T.A., L.L. Nelson, W.W. Young, L.W. Roberts, D.R. Roberts and
R.N. Wilkinson. 1973. Polymer formulations of mosquito larvicides. I.
50
-------
Effectiveness of polyethylene and polyvinyl chloride formulations of
chlorpyrifos applied to artificial field pools. Mosq. News. 33:148-155.
Mohsen, Z.H. and M.S. Mulla. 1981. Toxicity of blackfly larvicidal
i
formulations to some aquatic insects in the laboratory. Bull. Environ.
Contam. Toxicol. 26:696-703.
Moore, J.B. and S.G. Breeland. 1967. Field evaluation of two mosquito
larvicides, Abate and Dursban, against Anopheles quadrimaculatus and
associated Culex species. Mosq. News 27:105-111.
Moorthy, M.V., S. Chandrasekhar and V.R. Chandran. 1982. A note on acute
toxicity of chlorpyrifos to the freshwater fish Thilapia mossambica.
Pesticides 16:32.
Muirhead-Thomson, R.C. 1970. The potentiating effect of pyrethrins and
pyrethroids on the action of organophosphorus larvicides in simulium
control. Trans. R. Soc. Trop. Med. Hyg. 64:895-906.
Muirhead-Thomson, R.C. 1978. Relative susceptibility of stream
macroinvertebrates to temephos and chlorpyrifos, determined in laboratory
continuous-flow systems. Arch. Environ. Contam. Toxicol. 7:129-137.
Muirhead-Thomson, R.C. 1979. Experimental studies on macroinvertebrate
predator-prey impact of pesticides. The reactions of Rhyacophila and
Hydropsyche (Trichoptera) larvae to simulium larvicides. Can. J. Zool.
57:2264-2270.
Muirhead-Thomson, R.C. and J. Merryweather. 1969. Effects of larvicides
on simulium eggs. Nature 22:858-859.
51
-------
Mulla, M.S. and A.M. Khasawinah. 1969. Laboratory and field evaluation of
larvicides against chironomid midges. J. Econ. Entotnol. 62:37-41.
Mulla, M.S., R.L. Norland, D.M. Fanara, H.A. Darwazeh and D.W. McKean.
«
1971. Control of chironomid midges in recreational lakes. J. Econ. Entomol
64:300-307.
Mulla, M.S., R.L. Norland, W.E. Westlake, B. Dell, and J. St. Amant.
1973. Aquatic midge larvicides, their efficacy and residues in water,
soil, and fish in a warm water lake. Environ. Entomol. 2:58-65.
Naqvi, S.M. 1973. Toxicity of twenty-three insecticides to a tubificid
worm Branchiura sowerbyi from the Mississippi delta. J. Econ. Entomol.
66:70-74.
Nelson, J.H. and E.S. Evans, Jr. 1973. Field evaluation of larvicidal
effectiveness, effects on nontarget species and environmental residues of
a slow-release polymer formulation of chlorpyrifos, March-October 1973.
Entomological Special Study No. 44-022-73/75. AD/A-002054. National
Technical Information Service, Springfield, VA.
Nelson, J.H., D.L. Stoneburner, E.S. Evans, N.E. Pennington and M.V.
Meisch. 1976a. Diatom diversity as a function of insecticidal treatment
with a controlled release formulation of chlorpyrifos. Bull. Environ.
Contain. Toxicol. 15: 630-634.
Nelson, J.H., N.E. Pennington and M.V. Meisch. 1976b. Use of a controlled
release material for control of rice field mosquitoes. Arkansas Farm
Res. 25:9.
52
-------
Papst, M.H. and M.G. Boyer. 1980. Effects of two organophosphorus
insecticides on the chlorophyll a and pheopigment concentrations of
standing ponds. Hydrobiologia 69:245-250.
Peterson, R.H. 1976. Temperature selection of juvenile Atlantic salmon
(Salmo salar) as influenced by various toxic substances. J. Fish. Res.
Board Can. 33:1722-1730.
Phipps, G.L. and G.W. Holcombe. 1985a. A method for aquatic multiple
species toxicant testing: Acute toxicity of 10 chemicals to 5 vertebrates
and 2 invertebrates. Environ. Pollut. (Series A) 38:141-157.
Phipps, G.L. and G.W. Holcombe. 1985b. U.S. EPA, Duluth, MN. (Memorandum
to C.E. Stephan, U.S. EPA, Duluth, MN. October 22).
Polls, I., B. Greenberg and C. Lue-Hing. 1975. Control of nuisance midges
in a channel receiving treated municipal sewage. Mosq. News 35:533-537.
Ramke, D. 1969. Development of organophosphorus resistant Aedes nigromaculis
in the Tulane Mosquito Abatement District. Proc. Pap. Annu. Conf. Calif.
Mosq. Control Assoc. 37:63.
Rawn, G.P., G.R. Webster and G.M. Findley. 1978. Effect of pool bottom
substrate on residues and bioactivity of chlorpyrifos against larvae of
Culex tarsalis (Diptera; Culicidae). Can. Entomol. 110:1269-1276.
Rettich, F. 1977. The susceptibility of mosquito larvae to eighteen
insecticides in Czechoslovakia. Mosq. News 37:252-257.
Rettich, F. 1979. Laboratory and field investigations in Czechoslovakia
with fenitrothion, pirimiphos-methyl, temephos and other organophosphorus
53
-------
larvicides applied as sprays for control of Culex pipiens molestus and
Aedes cantans. Mosq. News 39: 320-328.
Roberts, D. and T.A. Miller. 1970. The effects of diatoms on the larvicidal
activity of Dursban, November 1969-March 1970. Entomological Special Study No.
31-002-71. AD-724647. National Technical Information Service, Springfield, VA.
Roberts, D.R. and T.A. Miller. 1971. Effects of polymer formulations of
Dursban and Abate on nontarget organism populations, April-October 1970.
Entomological Special Study No. 31-004-71. AD-729342. National Technical
Information Service, Springfield, VA.
Roberts, D.R., L.W. Roberts, T.A. Miller, L.L. Nelson and W.W. Young.
1973a. Polymer formulations of mosquito larvicides. III. Effects of a
polyethylene formulation of chlorpyrifos on non-target populations
naturally infesting artificial field pools. Mosq. News 33:165-173.
Roberts, L.W.,'D.R. Roberts, T.A. Miller, L.L. Nelson and W.W. Young.
1973b. Polymer formulations of mosquito larvicides. II. Effects of a
polyethylene formulation of chlorpyrifos on Culex populations naturally
infesting artificial field pools. Mosq. News 33:155-161.
Roberts, R.H., W.B. Kottkamp and M.V. Meisch. 1984. Larvicide evaluations
against the rice field mosquito Psorophora columbiae. Mosq. News 44:84-86.
Rongsriyam, Y., S. Prownebon and S. Hirakoso. 1968. Effects of insecticides
on the feeding activity of a guppy, a mosquito-eating fish in Thailand.
Bull. WHO 39:977-980.
Ruber, E. and J. Baskar. 1969. Sensitivities of selected microcrustacea
to eight mosquito toxicants. Proc. 55th Annu. Meet. N.J. Mosq. Exterm.
Assoc. 56:99-103.
54
-------
Ruber, E. and R. Kocor. 1976. The measurement of upstream migration in a
laboratory stream as an index of potential side-effects of temephos and
chlorpyrifos on Gammarus fasciatus. Mosq. News 36:424-429.
Saleh, M.S., I.A. Gaaboub and M.I. Kassem. 1981. Larvicidal effectiveness
of three controlled release formulations of Dursban and dirailin on Culex
pipiens and Aedes aegypti. J. Agric. Sci. 97:87-96.
Sanders, H.O. 1969. Toxicity of pesticides to the crustacean Gammarus
lacustris. Technical Paper No. 25. U.S. Fish and Wildlife Service, Columbia, MO,
Sanders, H.O. 1972. Toxicity of some insecticides to four species of
raalacositracan crustaceans. Technical Paper No. 66. U.S. Fish and Wildlife
Service, Washington, DC.
Sanders, H.O. and O.B. Cope. 1968. The relative toxicities of several
pesticides to naiads of three species of stoneflies. Limnol. Oceanogr.
13:112-117.
Schaefer, C.H. and E.F. Dupras, Jr. 1970. Factors affecting the stability
of Dursban in polluted waters. J. Econ. Entomol. 63:701-705.
Schimniel, S.G., R.L. Garnas, J.M. Patrick, Jr., and J.C. Moore. 1983. Acute
toxicity, bioconcentration, and persistence of AC 222,705, benthiocarb,
chlorpyrifos, fenvalerate, methyl parathion, and permethrin in the
estuarine environment. J. Agric. Food Chem. 31:104-113.
Scirocchi, A. and A. D'Erme. 1980. Toxicity of seven insecticides on some
species of freshwater fishes. Riv. Parassit. 41:113-121.
Siefert, R.E., C.F. Kleiner, B.R. Nordling, L.H. Mueller, D.K. Tanner,
A.W. Jarvinen, J.A. Zischke, N. Larson and R.L. Anderson. 1984. Effects
55
-------
of Dursban (chlorpyrifos) on nontarget aquatic organisms in a natural
pond undergoing mosquito control treatment. Progress Report. U.S. EPA,
Duluth, MN.
Smith, G.N., B.S. Watson, and F.S. Fischer. 1966. The metabolism of
[^C]0,0,diethyl-0-(3,5,6-trichloro-2-pyridyl)phosphorothiole (Dursban)
in fish. J. Econ. Entoraol. 59:1464-1475.
Steelman, C.D., B.R. Craven and E.J. Vallavaso. 1969. Control of southern
house mosquito larvae in Louisiana papermill log ponds. J. Econ. Entomol.
62:1152-1154.
Stephan, C.E., D.I. Mount, D.J. Hansen, J.H. Gentile, G.A. Chapman and
W.A. Brungs. 1985. Guidelines for deriving numerical national water
quality criteria for the protection of aquatic organisms and their uses.
PB85-227049. National Technical Information Service, Springfield, VA.
Stewart, J.P. 1977. Synergism of chlorpyrifos by DEF in the control of
organophosphorus resistant Culex pipiens quinquefasciatus larvae, with
notes on synergism of parathion and fenthion. Proc. Pap. Annu. Conf. Calif,
Mosq. Vector Control Assoc. 45:132-133.
Tagatz, M.E., N.R. Gregory and G.R. Plaia. 1982. Effects of chlorpyrifos
on field- and laboratory-developed estuarine benthic communities. J.
Toxicol. Environ. Health 10:411-421.
Tawfik, M.S. and R.H. Gooding. 1970. Dursban and Abate clay granules for
larval mosquito control in Alberta. Mosq. News 30:461-464.
56
-------
Taylor, R.T.. and H.F. Schoof. 1971, Experimental field treatment with
larvicides for control of Anopheles, Aedes, and Culex mosquitoes, j.
Econ. Entomol. 64:1173-1176.
Thayer, A. and E. Ruber. 1976. Previous feeding history as a factor in
the effect of temephos and chlorpyrifos on migration of Gammarus fasciatus.
Mosq. News 36:429-432.
Thirugnanam, M. and A.J. Forgash. 1977. Environmental impact of mosquito
pesticides: Toxicity and anticholinesterase activity of chlorpyrifos to
fi-sh in a salt marsh habitat. Arch. Environ. Contain. Toxicol. 5:415-425.
Thompson, A.H., C.L. Barnes and D.A. Mathews. 1970. Injection of Oursban
spray emulsion at half mile intervals controls mosquitoes and chironomid
larvae in large drainage channels. Proc. Pap. Annu. Conf. Calif. Mosq.
Control Assoc. 38:76-77,
U.S. Bureau of Commercial Fisheries. 1965. Unpublished laboratory data.
U.S. E1PA, Environmental Research Laboratory, Gulf Breeze, FL.
U.S. Bureau of Commercial Fisheries. 1967. Unpublished laboratory data.
U.S. EPA, Environmental Research Laboratory, Gulf Breeze, FL.
U.S. EPA. 1983a. Water quality standards regulation. Fed. Regist. 48:
51400-51413. November 8.
U.S. EPA. 1983b. Water quality standards handbook. Office of Water Regulations
and Standards, Washington, DC.
U.S. EPA. 1985. Technical support document for water-quality based toxics
control. Office of Water, Washington, DC. September.
57
-------
Verma, K.V. and S.J. Rahman. 1984. Determination of minimum lethal time
of commonly used mosquito larvicides. J. Cotnraun. Dis. 16:162-164.
Wallace, R.R., A.S. West, A.E. Downe and H.B. Hynes. 1973. The effects
of experimental blackfly (Diptera: Simuliidae) larviciding with Abate,
Dursban and methoxychlor on stream invertebrates. Can. Entomol. 105:
817-831.
Walsh, G.E. 1981. Effects of pesticides and industrial wastes on unicellular
algae and seagrass. Part IIA. In: "Research and Development: Experimental
Environments Branch, Progress Report for Fiscal Year 1981." Unpublished
laboratory data. U.S. EPA, Environmental Research Laboratory, Gulf Breeze, FL.
Walsh, G.E. 1983. Cell death and inhibition of population growth of marine
unicellular algae by pesticides. Aquatic Toxicol. 3:209-214.
Washino, R.K., K.G. Whitesell and D.J. Womeldorf. 1968. The effect of low
volume application of Dursban on nontarget organisms. Down Earth 24:21-22.
Washino, R.K., W. Ahmed, J.D. Linn and K.G. Whitesell. 1972a. Rice field
mosquito control studies with low volume Dursban sprays in Colusa County,
California IV. Effects upon aquatic nontarget organisms. Mosq. News 32:531-
537.
Washino, R.K., K.G. Whitesell, E.J. Sherman, M.C. Kramer and R.J. McKenna.
1972b. Rice field mosquito control studies with low volume Dursban sprays
in Colusa County, California. III. Effects upon the target organisms.
Mosq. News 32:375-382.
58
-------
Wilder,, W.H. and C.S. Schaefer. 1969. Organophosphorus resistance levels
in adults and larvae of the pasture mosquito, Aedes nigromaculis in the
San Joaquin Valley of California. Proc. Pap. Annu. Conf. Calif. Mosq.
Control Assoc. 37:64-67.
Wilkinson, R.N., W.W. Barnes, A.R. Gillogly and C.D. Minneraeyer. 1971.
Field evaluation of slow-release mosquito larvicides. J. Econ. Entomol.
64:1-3.
Wilton, D.P., L.E. Fetzer and R.W. Fay. 1973. Insecticide baits for
anopheline larvae. Mosq. News 33:198-203."
Winner, R.A., C.D. Steelman and P.E. Schilling. 1978. Effects of selected
insecticides on Romanomermis culicivorax, a mermithid nematode parasite
of mosquito larvae. Mosq. News 38:546-553.
Winterlin, W.L., K. Moilanen and W.E. Burgoyne. 1968. Residues of Dursban
insecticide following mosquito control applications. Down Earth 24:34-37.
Womeldorf, D.J., R.K. Washino, K.E. White and P.A. Gieke. 1970. Insecticide
susceptibility of mosquitoes in California: Response of Anopheles freeborni
larvae to organophosphorus compounds. Mosq. News 30:375-382.
Yap, H.H. and S.C. Ho. 1977. Evaluation of Dursban and Dowco 214 as
mosquito larvicides in rice-fields. Southeast Asian J. Trop. Med. Public
Health 8:63-70.
Zboray, E.P. and M.C. Gutierrez. 1979. Insecticide susceptibility of
mosquitoes in California: Status of organophosphorus resistance in larval
Culex Larsalis through 1978, with notes on mitigating the problem. Proc.
Pap. Annu. Conf. Calif. Mosq. Vector Control Assoc. 47:26-28.
59
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