[Comment: For dates of non-regulatory government publications,
publications of recognized organizations and associations, federal rules and
federal statutory provisions referenced in this rule, see rule
3745-1-03 of the Administrative
Code.]
This rule applies to water bodies located in the lake Erie
drainage basin. This rule establishes a
the methodology which
is required when developing tier I wildlife criteria for
bioaccumulative chemicals of concern (BCCs).
(A) General provisions.
(1) A tier I wildlife criterion is the
concentration of a substance which is likely to, if not exceeded, protect avian
and mammalian wildlife populations inhabiting the lake Erie drainage basin from
adverse effects resulting from the ingestion of water and aquatic prey taken
from surface waters of the lake Erie drainage basin. These criteria are based
on existing toxicological studies of the substance of concern and quantitative
information about the exposure of wildlife species to the substance through
food and water consumption. Separate avian and mammalian values are developed
using taxonomic class-specific toxicity data and exposure data for five
representative wildlife species. The wildlife species selected are
representative of avian and mammalian species resident in the Great Lakes basin
which are likely to experience the highest exposures to bioaccumulative
contaminants through the aquatic food web; they are the bald eagle, herring
gull, belted kingfisher, mink, and river otter.
(2) Rule
3745-1-39 of the Administrative
Code describes the procedures for calculating site-specific wildlife
criteria.
(3) The term "wildlife
value" (WV) is used to denote the value for each representative species which
results from using the equation in this rule, the value obtained from averaging
species values within a class, or any value derived from application of the
site-specific procedure provided in rule
3745-1-39 of the Administrative
Code. The WVs calculated for the representative species are used to calculate
taxonomic class-specific WVs. The WV is the concentration of a substance which,
if not exceeded, should better protect the taxon in question.
(4) "Tier I wildlife criterion," or "tier I
criterion" is used to denote the number derived from data meeting the tier I
minimum database requirements, and which will be protective of the two classes
of wildlife.
(B)
Calculation of wildlife values for tier I criteria.
(1) Equation for avian and mammalian wildlife
values. Tier I wildlife values
(WV) for BCCs
shall be calculated
using the following
equation
as follows:
Click to view
image
Where:
WV = wildlife value in milligrams of substance per liter
(mg/l).
TD = test dose in milligrams of substance per kilograms per day
(mg/kg-d) for the test species. This shall
be
is either a NOAEL or a LOAEL.
UFA = uncertainty factor for
extrapolating toxicity data across species (unitless). A species-specific UF
shall be
is
selected and applied to each representative species, consistent with the
equation.
UFs = UF for extrapolating from
subchronic to chronic exposures (unitless).
UFL = UF for LOAEL to NOAEL
extrapolations (unitless).
Wt = average weight in kilograms (kg) for the representative
species.
W = average daily volume of water consumed in liters per day
(l/d) by the representative species.
FTLi = average daily amount of food
consumed from trophic level I in kilograms per day (kg/d) by the representative
species.
BAFWLTLi =
bioaccumulation factor for wildlife food in trophic level I in liters per
kilogram (l/kg), developed using the BAF methodology contained in rule
3745-1-41 of the Administrative
Code. For consumption of piscivorous birds by other birds (e.g., herring gull
by eagles), the BAF shall be derived by multiplying the trophic level three BAF
for fish by a biomagnification factor to account for the biomagnification from
fish to the consumed birds.
(2) Identification of representative species
for protection. For bioaccumulative chemicals, piscivorous species are
identified as the focus of concern for wildlife criteria development in the
Great Lakes. Three avian species (eagle, kingfisher and herring gull) and two
mammalian species (mink and otter) serve as representative species for
protection. The TD obtained from toxicity data for each taxonomic class shall
be used to calculate WVs for each of the five representative species.
(3) Calculation of avian and mammalian
wildlife values and tier I criterion derivation. The avian WV is the geometric
mean of the WVs calculated for the three representative avian species. The
mammalian WV is the geometric mean of the WVs calculated for the two
representative mammalian species. The lower of the mammalian and avian WVs
shall be selected as the tier I criterion.
(C) Parameters of the effect component of the
wildlife criteria methodology.
(1)
Definitions. The following definitions provide additional specificity and
guidance in the evaluation of toxicity data and the application of this rule:
(a) Acceptable endpoints. For the purpose of
wildlife criteria derivation, acceptable subchronic and chronic endpoints are
those which affect reproductive or developmental success, organismal viability
or growth, or any other endpoint which is, or is directly related to,
parameters that influence population dynamics.
(b) Chronic effect. An adverse effect that is
measured by assessing an acceptable endpoint and results from continual
exposure over several generations, or at least over a significant part of the
test species' projected life span or life stage.
(c) Subchronic effect. An adverse effect,
measured by assessing an acceptable endpoint, resulting from continual exposure
for a period of time less than that deemed necessary for a chronic
test.
(2) Minimum
toxicity database for tier I criteria development. A TD value is required for
criterion calculation. To derive a tier I criterion for wildlife, the data set
shall provide enough data to generate a subchronic or chronic dose-response
curve for any given substance for both mammalian and avian species. In
reviewing the toxicity data available which meet the minimum data requirements
for each taxonomic class, the following order of preference shall be applied to
select the appropriate TD to be used for calculation of individual WVs. Data
from peer-reviewed field studies of wildlife species take precedence over other
types of studies, where such studies are of adequate quality. An acceptable
field study
shall be
is of subchronic or chronic duration, provide a
defensible, chemical-specific dose-response curve in which cause and effect are
clearly established, and assess acceptable endpoints as defined in this
document. When acceptable wildlife field studies are not available, or
determined to be of inadequate quality, the needed toxicity information may
come from peer-reviewed laboratory studies. When laboratory studies are used,
preference shall be given to laboratory studies with wildlife species over
traditional laboratory animals to reduce uncertainties in making interspecies
extrapolations. All available laboratory data and field studies shall be
reviewed to corroborate the final tier I criterion, to assess the
reasonableness of the toxicity value used, and to assess the appropriateness of
any UFs which are applied. When evaluating the studies from which a test dose
is derived in general, the following requirements shall be met:
(a) The mammalian data
shall come from at least one well-conducted
study of ninety days or greater designed to observe subchronic or chronic
effects as defined in this document.
(b) The avian data shall come from at least one well-conducted study
of seventy days or greater designed to observe subchronic or chronic effects as
defined in this rule.
(c) In
reviewing the studies from which a TD is derived for use in calculating a WV,
studies involving exposure routes other than oral may be considered only when
an equivalent oral daily dose can be estimated and technically justified
because the criteria calculations are based on an oral route of
exposure.
(d) In assessing the
studies which meet the minimum data requirements, preference
shall be
is
given to studies which assess effects on developmental or reproductive
endpoints.
(3) Selection
of TD data. In selecting data to be used in the derivation of WVs, the
evaluation of acceptable endpoints, as defined in paragraph (C)(1) of this
rule, shall be the primary selection criterion. All data not part of the
selected subset may be used to assess the reasonableness of the toxicity value
and the appropriateness of the UFs which are applied
,
. Use of such data shall
be as follows:
(a) If more than one TD
value is available within a taxonomic class, based on different endpoints of
toxicity, that TD which is likely to reflect best potential impacts to wildlife
populations through resultant changes in mortality or fecundity rates
shall be
is
used for the calculation of WVs.
(b) If more than one TD is available within a
taxonomic class, based on the same endpoint of toxicity, the TD from the most
sensitive species shall be
is used.
(c) If more than one TD based on the same
endpoint of toxicity is available for a given species, the TD for that species
shall be
is
calculated using the geometric mean of those TDs.
(4) In those cases in which a TD is available
in units other than milligrams of substance per kilograms per day (mg/kg/d),
the following procedures shall be used to convert the TD to the appropriate
units prior to calculating a WV.
(a) If the TD
is given in milligrams of toxicant per liter of water consumed by the test
animals (mg/l), the TD shall be
is multiplied by the daily average volume of
water consumed by the test animals in liters per day (l/d) and divided by the
average weight of the test animals in kilograms (kg).
(b) If the TD is given in milligrams of
toxicant per kilogram of food consumed by the test animals (mg/kg), the TD
shall be
is
multiplied by the average amount of food in kilograms consumed daily by the
test animals (kg/d) and divided by the average weight of the test animals in
kilograms (kg).
(5)
Drinking and feeding rates.
(a) When drinking
and feeding rates and body weight are needed to express the TD in milligrams of
substance per kilograms per day (mg/kg/d), they shall be obtained from the
study from which the TD was derived. If not already determined, body weight,
and drinking and feeding rates shall be
are converted to a wet weight basis.
(b) If the study does not provide the needed
values, the values shall be determined from appropriate scientific literature.
For studies done with domestic laboratory animals, either the "Registry of
Toxic Effects of Chemical Substances" or "Recommendations for and Documentation
of Biological Values for Use in Risk Assessment"
shall
should be
consulted. When these references do not contain exposure information for the
species used in a given study, either the allometric equations in this rule or
the exposure estimation methods presented in chapter 4 of "The
Wildlife Exposure Factors Handbook" should be applied to
approximate the needed feeding or drinking rates. The choice of the methods
described in this paragraph is at the discretion of the director.
(c) For mammalian species, the
general allometric equations are as follows:
(i) F = 0.0687
(Wt)
0.82
Where:
F = feeding rate of mammalian species in kilograms per day
(kg/d) dry weight.
Wt = average weight in kilograms (kg) of the test
animals.
(ii) W = 0.099
(Wt)
0.90
Where:
W = drinking rate of mammalian species in liters per day
(l/d).
Wt = average weight in kilograms (kg) of the test
animals.
(d) For
avian species, the general allometric equations are:
(i) F = 0.0582
(Wt)
0.65
Where:
F = feeding rate of avian species in kilograms per day (kg/d)
dry weight.
Wt = average weight in kilograms (kg) of the test
animals.
(ii) W = 0.059
(Wt)
0.67
Where:
W = drinking rate of avian species in liters per day
(l/d).
Wt = average weight in kilograms (kg) of the test
animals.
(6) LOAEL to NOAEL extrapolations
(UFL). In those cases in which a NOAEL is unavailable as
the TD and a LOAEL is available, the LOAEL may be used to estimate the NOAEL.
If used, the LOAEL shall be divided by an UF to estimate a NOAEL for use in
deriving WVs. The value of the UF shall not be less than one
and shall not
nor exceed ten, depending on the dose-response curve
and any other available data, and is represented by UFL in the equation
expressed in paragraph (B)(1) of this rule.
(7) Subchronic to chronic extrapolations
(UFs). In instances where only subchronic data are available, the TD may be
derived from subchronic data. In such cases, the TD shall be divided by an UF
to extrapolate from subchronic to chronic levels. The value of the UF shall not
be less than one and shall not
nor exceed ten, and is represented by
UFs in the equation expressed in paragraph (B)(1) of
this rule. This factor shall be used when assessing highly bioaccumulative
substances where toxicokinetic considerations suggest that a bioassay of
limited length underestimates chronic effects.
(8)
Interspecies
Selection and
use of interspecies extrapolations (UF
A)
.
shall be as
follows:
(a) The selection of the
UFA
shall be
is based on the available toxicological data and
on available data concerning the physicochemical, toxicokinetic, and
toxicodynamic properties of the substance in question and the amount and
quality of available data. This value is a UF that is intended to account for
differences in toxicological sensitivity among species.
(b) For the derivation of tier I criteria, a
UFA shall not be less than one
and shall not
nor exceed one hundred, and shall be applied
applies to each of the five representative species,
based on existing data and the director's best professional judgement. The
value of UFAmay differ for each of the representative species.
(c) For tier I wildlife criteria, the
UFA
shall be
is used only for extrapolating toxicity data
across species within a taxonomic class, except as provided in this paragraph.
The tier I UFA is not intended for interclass
extrapolations because of the poorly defined comparative toxicokinetic and
toxicodynamic parameters between mammals and birds. However, an interclass
extrapolation employing a UFA may be used for a given chemical if it can be
supported by a validated biologically-based doseresponse model or by an
analysis of interclass toxicological data, considering acceptable endpoints,
for a chemical analog that acts under the same mode of toxic action.