APP203305 Scorpio Ornamental Fungicide - EPA...Updated science memo for application to import or manufacture Scorpio Ornamental Fungicide for release (APP203305) April 2018 The PEC

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Updated science memo for application to import or manufacture Scorpio Ornamental Fungicide for release (APP203305)

April 2018

UPDATED RISK ASSESSMENT

APP203305 – Scorpio Ornamental Fungicide Substance database ID: 48972

April 2018

Background

In the previous risk assessment, high risks to the environment were identified. The EPA

requested that the applicant provide additional modelling to assess the spot treatment scenario.

The applicant was unable to provide this information but was able to provide a revised (lower)

application rate. The application rate was decreased to half the original rate, and the number of

applications reduced to 2 from 3. The new application rate is 300 g ai/ha of tebuconazole and

150 g ai/ha of trifloxystrobin with a frequency of 2, the minimum interval between applications is

5 days.

This updated risk assessment only re-evaluates the risks to the environment identified in the

previous risk assessment (ie those above the level of concern, LOC). Since the application rate

and frequency modelled in this risk assessment are lower than those modelled in the previous

risk assessment, any previous risk assessment is considered more conservative. As such, if no

risk for a particular endpoint or model species was identified in the previous risk assessment

(using the higher application rate and application frequency), it is not necessary to re-model

these scenarios using the reviser lower application rate and application frequency.

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April 2018

Updated GAP table

Table 1 represents the worst case scenario with maximum application rate and frequency.

Table 1: List of intended uses for Scorpio Ornamental Fungicide

Crop and/or

situation (a)

Use

pattern

(b)

Pests or group of

pests controlled

(c)

Mixture Application

Type (d-f) Conc of ai (g) Method and

kind (h-i)

Maximum

Number (k)

Interval between

applications –

days (minimum)

Maximum application rate kg ai/ha

Azaleas,

ornamentals,

roses, plants of

the Myrtaceae

family

F, G

Azalea petal

blight, botrytis,

downy mildew,

leaf spots, rusts,

black spots etc.

SC Tebuconazole: 200

Trifloxystrobin: 100

Broadcast 2 5

Tebuconazole: 0.3

Trifloxystrobin: 0.15

Aerial 2 5 Tebuconazole: 0.3

Trifloxystrobin: 0.15

a Where relevant, the use situation should be described (eg fumigation of soil) b Outdoor or field use (F), glasshouse application (G) or indoor application (I). c eg biting and sucking insects, soil borne insects, foliar fungi, weeds d eg wettable powder (WP), emulsifiable concentrate (EC), granule (GR), suspension concentrate (SC) e CropLife international, 2008. Technical Monograph no 2, 6th edition. Catalogue of pesticide formulation types and international coding system f All abbreviations used must be explained g g/kg or g/l or others h Method, eg high volume spraying, low volume spraying, spreading, dusting, drench, aerial, etc , i Kind, eg overall, broadcast, aerial spraying, row, individual plant, between the plant - type of equipment used must be indicated. If spraying include droplet size spectrum j growth stage at last treatment (BBCH Monograph, Growth Stages of Plants, 1997, Blackwell (ISBN 3-8263-3152-4) , including where relevant, information on season at time of application k Indicate the minimum and maximum number of application possible under practical conditions of use l Remarks may include: Extent of use/economic importance/restrictions

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April 2018

Updated environmental risk assessment

Aquatic risk assessment

Spray drift

The previous risk assessment indicated that the acute toxicity of the active ingredient trifloxystrobin to

aquatic organisms (lowest acute toxicity value of 0.011 mg/L for Daphnia magna, 48-hour LC50) drives

the largest downwind buffer zones. This updated risk assessment only re-evaluates the downwind

buffer zones required for the active ingredient trifloxystrobin. As such, the risks to the aquatic

environment from the active ingredient tebuconazole, and the chronic risk from trifloxystrobin, are

considered mitigated by any downwind buffer zone calculated using the acute toxicity trifloxystrobin

endpoint.

Although aerial applications are likely to be limited to helicopter spot-spraying, the EPA staff used the

input parameters for the standard agricultural fungicide scenario (fixed-wing aircraft) in AgDisp due to

a lack of application details in regard to spot-spraying. Application details regarding spot-spraying was

requested from the applicant but was not provided. The fixed-wing aircraft scenario is a worst-case

scenario, as it assumes that the substance will be applied over a very large area, which may not

necessarily be a realistic scenario.

The AgDisp input parameters for aerial application are updated to reflect the new application rate

(Table 2), this included the fractions of trifloxystrobin and tebuconazole, which are now set at 0.003

and 0.006, respectively. A medium spray droplet size was assessed, according to the American

Society of Agricultural and Biological Engineers (ASABE) classifications. For both active ingredients,

the fraction of non-volatiles was assumed to be 0.009 as the sum of the active ingredients in the

substance Scorpio Ornamental Fungicide is 300 g/L; 1.5 L/ha (450 g total active ingredient), 50 L/ha

spray volume.

Table 2: Input parameters spray drift model for trifloxystrobin

Input parameters Trifloxystrobin

Application rate (kg ai/ha) 0.15

Number of applications 2

Application interval 5

Application method Broadcast (high-boom), Airblast, Air

Droplet size Medium (for ground boom and aerial)

DT50 soil 0.67

DT50 water 3.5

Koc 1642

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April 2018

Toxicity endpoint (trifloxystrobin) 0.011 mg/L (Daphnia magna, acute)*

Assessment factor (threatened species) 20

* It was demonstrated in the previous assessment that acute toxicity of the formulation to fish, aquatic invertebrates and algae

was driven by trifloxystrobin.

Table 3 summarises the downwind buffer zones.

Table 3: Downwind buffer zones (m) to protect aquatic organisms from spray drift (threatened species)

Active ingredient High ground boom

(medium droplets)

Airblast

(dense – sparse) orchard Aerial

Trifloxystrobin 2 m 22 - 28 m 108 m

Runoff

The REXTOX model was used to calculate the required buffer zone to protect the aquatic

environment from adverse effects of Scorpio Ornamental Fungicide due to runoff. The input

parameters are presented in Table 4. The equations applied for predicting runoff in REXTOX are

described in Probs et al. (2005). For this assessment, the default 30 mm rainfall value has been used.

A crop interception value of 50% has been applied and a 5% slope has been adopted in the first

instance. EFSA (2014) provides a range of crop interception factors, and while ornamentals are not

specifically addressed, it appears a value of 50% interception would provide a suitably conservative

estimate (using leafy vegetables with an intermediate canopy cover as a surrogate crop). It is

assumed the runoff event occurs three days after the final application. It should be noted that the risk

assessment is based on the treatment of the whole area. With spot treatment of some trees, this

application rate will not be reached. The runoff is also expected to be lower.

In the previous assessment the runoff buffer zone was driven by tebuconazole. This assessment will

focus on this active ingredient, since the buffer zone for tebuconazole will be protective of any risks

from use of trifloxystrobin.

Table 4: Input parameters and calculation of runoff buffer zone for the refined risk assessment

Input parameters Tebuconazole

Application rate (kg ai/ha) 0.3

Number of applications 2

Time between applications 5

DT50 soil 57.5

Multiple application factor (MAF) 1.9

Kd 16.39 (lowest value from non-sandy soil)

Slope 5%

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April 2018

Heterogeneity factor 0.5

Crop interception 50%

Toxicity endpoint (tebuconazole) 0.010 mg/L (Daphnia magna, chronic)

Assessment factor 10

Buffer zone (m) 7

A buffer zone of 7 m is calculated to allow reduction in the edge-of-field tebuconazole concentrations

to an acceptable level.

Conclusions of the aquatic risk assessment

To protect the aquatic environment from use of Scorpio Ornamental Fungicide, the following buffer

zones are required to mitigate the risks (for the worst case scenario (“blanket-spray” approach)):

The downwind buffer zone for ground-based applications is 5 metres (m). This control will be

over-ruled by the runoff buffer zone.

The downwind buffer zone for airblast applications in dense orchards is 25 m.

The downwind buffer zone for airblast applications in sparse orchards is 30 m.

The downwind buffer zone for aerial applications is 110 m.

The runoff buffer zone for all application methods is 10 m and should be observed in all

directions from a waterbody.

Buffer zones are rounded up so it is easier for the end-user to visualise and remember the buffer

zone.

It has not been possible to assess the risks from spot treatments, the total concentration per hectare

is anticipated to be lower in this scenario. Risks are considered to be lower.

Risk assessment for sediment-dwelling organisms

The risk assessment at the initial higher application rate indicated that there was no risk from

trifloxystrobin and a potential risk from tebuconazole. The extent of the risk from tebuconazole to

sediment-dwelling organisms at the lower application rate was further evaluated.

The GENEEC2 model was run to evaluate the peak concentration for aerial application (highest risk

profile). All input parameters except the application rate, frequency and interval were the same as

from the initial risk assessment (see Table 4).

Thereafter, the concentration and risk to the sediment were evaluated using the same input

parameters as during the initial assessment for the higher application rate with the exception of the

the Predicted Environmental Concentration in water (PECwater). In this case the PECwater was 0.01472

mg/L based on the results of the GENEEC2 modelling. This value was then used to calculate the PEC

in sediment.

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April 2018

The PEC sediment was calculated to be 0.30 mg/kg, the Predicted No Effect Concentration (PNEC)

was determined to be 0.40 mg/kg (endpoint 40 mg/kg with an assessment factor of 100).

The Risk Quotient (RQ) for sediment-dwelling organisms was determined to be 0.76 and therefore the

risks to sediment-dwelling organisms are considered below the level of concern.

Table 5: GENEEC2 results

RUN No. 1 FOR Tebuconazole ON Ornamental * INPUT VALUES *

--------------------------------------------------------------------

RATE (#/AC) No.APPS & SOIL SOLUBIL APPL TYPE NO-SPRAY INCORP

ONE(MULT) INTERVAL Koc (PPM ) (%DRIFT) (FT) (IN)

--------------------------------------------------------------------

0.270( 0.524) 2 5 910.4 32.0 AERL_B( 13.0) 0.0 0.0

FIELD AND STANDARD POND HALFLIFE VALUES (DAYS)

--------------------------------------------------------------------

METABOLIC DAYS UNTIL HYDROLYSIS PHOTOLYSIS METABOLIC COMBINED

(FIELD) RAIN/RUNOFF (POND) (POND-EFF) (POND) (POND)

--------------------------------------------------------------------

57.50 2 0.00 590.00-73160.00 38.70 38.68

GENERIC EECs (IN MICROGRAMS/LITER (PPB)) Version 2.0 Aug 1, 2001

--------------------------------------------------------------------

PEAK MAX 4 DAY MAX 21 DAY MAX 60 DAY MAX 90 DAY

GEEC AVG GEEC AVG GEEC AVG GEEC AVG GEEC

--------------------------------------------------------------------

14.72 14.48 13.07 10.48 8.97

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April 2018

Groundwater risk assessment

In the previous assessment it was determined that there was a potential for groundwater

contamination by metabolite CGA321113 (from trifloxystrobin), and tebuconazole and its metabolite

1,2,4-triazole. Trifloxystrobin did not show a potential to contaminate the groundwater in sensitive

soils. Therefore, it was not included in the current risk assessment (Table 6).

Table 6: Input parameters for Sci-Grow analysis and resulting PEC values

Input parameters Tebuconazole 1,2,4-triazole

(tebuconazole metabolite)

CGA321113

(trifloxystrobin metabolite)

Application rate (g ai/ha) 300 0.0965 (fraction formation =

0.321) 0.15 (fraction formation = 1)

Application rate (lb ai/acre)1 0.268 0.086 0.134

Crop interception 50% 50% 50%

Number of applications 2 2 2

Koc2 910.4 43 84

Aerobic soil DT50 (days) 57.5 (field) 92.8 73.9

PECgw (µg/L) 0.0189 0.277 0.153

1 The application rate is conversion from kg ai/ha to lb/acre (the units required to be entered into the model) by multiplying it by 0.892 2 Lowest Koc from a non-sandy soil (normalised values for the OC, temperature and pH)

Conclusions of the groundwater risk assessment

The updated groundwater assessment for tebuconazole indicates this active constituent will not be

found in groundwater at relevant concentrations. The concentration is compared to the European

Union (EU) limit for the maximum permissible concentration of pesticide active ingredients and their

relevant metabolites in groundwater. This limit concentration is 0.1 µg/L. The more persistent and

mobile metabolites, 1,2,4-Triazole and CGA321113, may be above a concentration of 0.1 µg/L in

groundwater in vulnerable soils.

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April 2018

Terrestrial risk assessment

It was determined that a value of 50% interception would provide a suitably conservative estimate, for

example, based on leafy vegetables with an intermediate canopy cover. This will be applied in

determining PEC values in soil.

Soil organisms risk assessment

No acute risks, only chronic risks were identified in the previous assessment. The current risk

assessment will only focus on the chronic risks.

There are acute and chronic earthworm toxicity data available for the formulated product. Endpoints

for the formulated product for earthworms are used to determine the risks, since the toxicity of the

product expressed as mg ai is higher than the effects obtained from tests with the individual active

ingredients. Accordingly, values for the formulated product will be used in the assessment (Table 7).

The end use product has a density of 1.08-1.12 g/cm3. Applying a mean value of 1.10 g/cm3, a single

application rate of 1.5 L product/ha equates to 1650 g product/ha. The risk assessment is based on a

single application.

Table 7: Chronic TER values for soil organisms – Scorpio Ornamental Fungicide

Species

NOEC

(mL

product/ha)

Drift (%) PEC (mL

product/ha)

TER

acute Conclusion

Scenario – 3000 mL product/ha – “in-field”

All application

types

1710 mL

product/ha NA 7501 2.28

Above LOC for threatened/non-

threatened species

Scenario – 3000 mL product/ha – “off-field”

Ground boom

1710 mL

product/ha 8.022 60.15 28.4

Below LOC for non-threatened

species.

Above LOC for threatened

species

Airblast 29.23 219 7.8

Below the LOC for non-threatened

species.


species

Air 174 128 13.4

Below the LOC for non-threatened

species.


species

1) The toxicity value was determined based on an application rate of the product to the soil surface. The PEC is based

on the maximum product rate with a foliar interception value of 50% (single application)

2) Drift factor at 3 m off crop, BBA high boom.

3) Drift factor at 3 m off crop, BBA fruit crops (early season).

4) Drift factor at 2 m off crop, AgDISP, medium droplet size.

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April 2018

The Toxicology Exposure Ratios (TER) above for the chronic risk assessment are based on a single

application rate and assume 50% interception for both in- and off-field assessments. EFSA (2014)

provides a range of crop interception factors, and while ornamentals are not specifically addressed, it

appears a value of 50% interception would provide a suitably conservative estimate, for example,

based on leafy vegetables with an intermediate canopy cover. The product can be applied twice with

a relatively short interval between applications. However, Multiple Application Factors (MAFs) for the

end use product itself cannot be derived as the active constituents in the product behave differently.

There are individual active constituent toxicity data for tebuconazole (56 day No Observed Effect

Concentration (NOEC) = 10 mg ai/kg soil), and for trifloxystrobin (28 day NOEC = 7 mg ai/kg soil dry

weight). Using the same conversion, the product NOEC of 1710 mL product/ha (1880 g/ha) equates

to a soil concentration of 2.5 mg product/kg, which indicates it is much more toxic than either of the

individual active constituents.

It was determined that, for the risks to be below the level of concern the maximum acceptable spray

drift is 4.6% of the application rate (maximum off field deposition = endpoint/50 = 1710 mL/ha /50 =

34.2 mL/ha. Maximum safe spray drift = maximum off field deposition / (application rate x crop

inception) = 0.046 = 4.6%).

It was determined that in case of ground-based applications the zone impacted is 3-5 m based on the

BBA spray curves. For aerial application, this is 42 m based on the AgDisp spray curves.

Conclusions of the soil organism risk assessment

The off-field risks to threatened soil organisms are above the LOC. In-field risks are identified for

threatened and non-threatened species. These risks are determined in the scenario that the full

application rate is applied, with spot treatment this is likely to be significantly less. Therefore, the risks

from spot treatment are anticipated to be lower.

Non-target plant risk assessment

The risks to plants were considered to be acceptable in the previous assessment.

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April 2018

Bird risk assessment

The previous assessment indicated that the highest risks were due to the chronic toxicity of

tebuconazole. The refinement of the NOEC, explained in Appendix K (bird risk assessment) of the

first science memo, will be applied to this risk assessment (NOEC of 14.8 mg/kg bw/d).

Table 8: Chronic TER values for birds – screening and first tier

Crops & BBCH

class

Generic focal

species1

Toxicity endpoint

value (mg/kg

bw/d)*

TER ratio Conclusion

Application rate 0.6 (kg/ha) – Number of applications = 2 with a 5 day spray interval

Screening

Ornamentals

Small

insectivorous bird,

“tit”

14.8 mg/kg bw/d 3.0

Above the LOC for

non-threatened and

threatened species

First Tier

Ornamentals and

plant nursery

application to

plants

Small

insectivorous bird,

“tit” Foliar insects

100% foliar insects

14.8 mg/kg bw/d 3.0

Above the LOC for

non-threatened and

threatened species

Ornamentals and

plant nursery

application to

plants – Exposure

to underlying

ground

Small

insectivorous/worm

feeding species

“thrush” ground

invertebrates with

interception 100%

soil dwelling

invertebrates

14.8 mg/kg bw/d 20.3

Below the LOC for non-

threatened and

threatened species

Applying these refinements and the lower application rate and frequency, the risk to non-threatened

and threatened species still cannot be mitigated. For the TER values to be acceptable with these

different refinement arguments, birds would need to still need to forage outside the treated area for

~70% of the time over the 21 day assessment period for the risks to be considered acceptable to

threatened species. If the substance was used on a broad scale using the “blanket-approach” it is

considered unlikely that these resources and territory are available. It also be noted that this risk

assessment has been refined by using a geometric mean NOEC rather than the lowest NOEC.

However, even with this refinement, risks are still identified. As such, EPA staff conclude that the risks

to birds from the use of Scorpio is above the LOC. For spot-treatment it is more likely that sufficient

food is available outside the treated area, however, food availability is highly site-, season- and

ecosystem-specific. Therefore, a site specific assessment should be performed. This risk assessment

would need to consider the likely presence of any birds in any treated area and the availability of food

from other non-treated areas. While the risks from spot treatment will be lower than those associated

with broad scale application, they are still above the LOC.

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April 2018

Pollinator risk assessment

In the previous risk assessment the risk to pollinators was considered below the LOC.

Non-target arthropod risk assessment

In the previous risk assessment, risks were identified in-field, and for two of the four species off-field,

during aerial application. The risk assessment focusses on these previously identified risks.

Table 9: In-field HQ values for non-target arthropods

Species LR50

(mL/ha)

Application rate

(mL/ha) MAF

Hazard

Quotient Conclusion

Parasitic wasps 1091 1500 1.7 2.3 Risk above the

LOC

Predatory mites >2000 1500 1.7 <1.3 Risk below the

LOC

Predatory bugs 321 1500 1.7 7.9 Risk above the

LOC

Ladybirds 3093 1500 1.7 0.82 Risk below the

LOC

Table 10: Off-field HQ values for non-target arthropods

Species LR50

(mL ai/ha)

Application rate

(mL ai/ha) MAF

Hazard

Quotient Conclusion

Aerial application (drift factor 17%1)

Predatory wasps 1091 1500 1.7 0.39 Risk below the

LOC

Predatory bugs 321 1500 1.7 1.35 Risk below the

LOC

Airblast (drift factor 29.2%2)

Predatory wasps 1091 1500 1.7 0.68 Risk below the

LOC

Predatory bugs 321 1500 1.7 2.3 Risk above

the LOC

1) Drift factor at 3 m off crop, AgDISP, medium droplet size.

2) Drift factor at 3 m off crop, BBA fruit crops (early season).

Conclusion for non-target arthropod risk assessments

Risks to non-target arthropods are above the LOC for in-field. Risks to non-target arthropods are

above the LOC for off-field for airblast application. Risks to non-target arthropods are above the LOC

for off-field for aerial application.

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April 2018

Conclusions of the updated environmental risk assessment

The current risk assessment is based on the worst-case scenario in which a full area is sprayed, and

in the case of the aerial scenario, a fixed wing aircraft is modelled.

For most use patterns, isolated trees or rows of trees will be targeted and the “full-blanket” approach

will not be applied. It is also likely that these trees will be targeted using helicopter spraying which can

be more precise than in case of a fixed wing aircraft. When individual trees are sprayed, exposure will

be lower and off-target drift is likely to be lower. In particular, the targeted approach will decrease

some of the identified risks. Insufficient information is available to quantify the risks for this use

pattern.

Aquatic environment

Buffer zones for waterbodies are required to mitigate the risks to the aquatic environment.

For protection of waterbodies due to runoff, a buffer zone of 10 m must be observed

irrespective of the wind direction.

For aerial and boom spray application equipment using medium sized droplets as defined by

the ASABE Standard (S572) or the British Crop Production Council guideline. Smaller sized

droplets should not approved.

The downwind buffer zone for ground-based applications is 5 m. This buffer zone will be

overruled by the runoff buffer zone.

The downwind buffer zone for air blast is 25-30 m.

The downwind buffer zone for aerial application is 110 m.

Sediment

No risks for sediment-dwelling organisms were identified.

Groundwater

The metabolites, 1,2,4-triazole and CGA321113, may approach a groundwater concentration above

0.1 µg/L in vulnerable soils. The limit concentration is the EU limit for the maximum permissible

concentration of pesticide active ingredients and their relevant metabolites.

Soil organisms

The chronic risk for soil organisms in-field is considered above the LOC. Off-field the chronic risks for

threatened species during aerial application are considered above the LOC.

Plants

The risks to non-target plants are below the LOC.

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April 2018

Birds

The risk to non-threatened and threatened species is considered above the LOC. When spot

treatment is applied, it should be evaluated if there is sufficient food and territory available outside the

application area at the time of application. However, if an attractive food source is sprayed (for

example, flowers or insects living on/near the tree) it is still likely that birds will be exposed above the

safe dose. Therefore, the EPA staff considers that there will always be a risk from the application of

the substance to birds.

Pollinators and beneficial insects

The risk to pollinators is considered above the LOC.

The in-field risks for predatory wasps and predatory bugs are above the LOC. Off-field, the risk to

predatory bugs is considered above the LOC (airblast application only).

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April 2018

Updated human health risk assessment

As the application rate of Scorpio Ornamental Fungicide was revised due to the environmental risks,

relevant parts of the human health risk assessment were repeated with the new application rate to

determine whether the previously determined controls remain appropriate, or whether they can be

revised if the lower application rate is approved.

Operator exposure risk assessment

As expected a halving of the application rate of tebuconazole resulted in a halving of the risk noted in

Tables 25 and 26 of the Science Memo with acceptable risk in the absence of Personal Protective

Equipment (PPE).

Table 11: Output of operator mixing, loading and application exposure assessment for tebuconazole

Exposure Scenario

Estimated operator

exposure (mg/kg

bw/day)

Risk Quotient

Boom

No personal protective equipment (PPE)1 during mixing,

loading and application

0.0229 0.76

Gloves only during mixing and loading 0.0222 0.74

Gloves only during application 0.0192 0.64

Full PPE during mixing, loading and application (excluding

respirator)

0.0015 0.05

Full PPE during mixing, loading and application (including FP1,

P1 and similar respirator achieving 75 % inhalation exposure

reduction)

0.0014 0.05



reduction)

0.0014 0.05

Backpack - High Level Target

No PPE during mixing, loading and application 0.0521 1.74

Gloves only during mixing and loading 0.0458 1.53

Gloves only during application 0.0418 1.39

Full PPE during mixing, loading and application (excluding

respirator)

0.0049 0.16

1 ‘Full PPE’ includes: gloves, hood/visor, coveralls, and heavy boots during application and gloves during mixing and loading.

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April 2018



reduction)

0.003771 0.13



reduction)

0.003546 0.12

Re-entry exposure risk assessment

The RQ for re-entry (Table 27 of the Science Memo) are lowered due to the lower application rate for

tebuconazole, nevertheless the reduction does not remove the need for Restricted Entry Intervals

(REIs).

Table 12: Output of the re-entry worker exposure assessment for tebuconazole

Active

ingredient Crop/activity

Internal (absorbed)

dose available for

systemic

distribution

(mg/kg bw/8 hours)

AOEL

(mg/kg

bw/day)

RQ

immediately

after

application

REI

Tebuconazole

Ornamentals –

Cut/sort/bundle/carry 0.22 0.03

7.37

(without

gloves)

28.8

(without gloves)

Tebuconazole

Ornamentals –

Cut/sort/bundle/carry 0.06 0.03

2.06

(with gloves)

10.5

(with gloves)

The REI required for re-entry activities are 29 days without gloves and 11 days with gloves. The re-

entry risks for trifloxystrobin have not be re-modelled as the risks were acceptable with gloves and the

REI without gloves was shorter than the revised REI associated with tebuconazole.

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April 2018

Bystander risk assessment

As expected the RQ for bystander re-entry (Table 13) was lowered due to lower application rate for

tebuconazole but the main risk assessment is unchanged as the original RQ was <1 for boom

application. However, the new risk assessment now shows an RQ of <1 for aerial forestry use.

Table 13: Output of the bystander exposure assessment for tebuconazole

Exposure Scenario

Estimated exposure of 15

kg toddler exposed through

contact to surfaces 8 m

from an application area

(µg/kg bw/day)

RQ

Buffer zone needed to

reduce toddler

exposure to the AOEL

Boom

High boom, fine droplets 2.66 0.0888 0

High boom, coarse droplets 0.42 0.0141 0

Low boom, fine droplets 0.90 0.0300 0

Low boom, coarse droplets 0.21 0.0071 0

Aerial (forestry)

Swathe width 7.5 m, medium-

coarse droplet size

15.84 0.5279 4

Swathe width 7.5 m, coarse-

very coarse droplets

13.87 0.4623 0

Swathe width 7.5 m, extremely

coarse droplets

12.40 0.4134 0

Revised conclusion of the human health risk assessment

No changes to the conclusions for the operator assessment are required.

Predicted exposures to tebuconazole for workers re-entering and working in areas where Scorpio

Ornamental Fungicide has been applied exceed the Acceptable Operator Exposure Level (AOEL).

The REI intervals required for re-entry activities are 29 days without gloves and 11 days with gloves.

The estimated bystander exposures to tebuconazole after boom and aerial (forestry) application are

below the AOEL for the bystander 8 m from the application area. With the reduced application rates, a

buffer zone of 12 m is no longer required to protect bystanders for the modelled droplet sizes for

aerial (forestry application).

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April 2018

Appendix A: Standard Terms and Abbreviations

Abbreviation Definition

ai Active ingredient

AOEL Acceptable Operator Exposure Level

ASABE American Society of Agricultural and Biological Engineers

BBA Federal Biological Research Centre for Agriculture and Forestry

BBCH Biologische Bundesanstalt, Bundessortenamt und CHemische Industrie

bw body weight

cm centimetres

DT50 Dissipation Time (days) for 50% of the initial residue to be lost

EPA Environmental Protection Authority

EU European Union

g grams

GAP Good Agricultural Practice

GENEEC Generic Estimated Environmental Concentration

ha hectare

HQ Hazard Quotient

kg Kilogram

Koc organic carbon adsorption coefficient

L litres

lb pounds

LOC Level Of Concern

m3 cubic metre

MAF Multiple Application Factor

mg milligram

NOEC No Observed Effect Concentration

PEC Predicted Environmental Concentration

PNEC Predicted No Effect Concentration

ppb parts per billion (10-9)

PPE Personal Protective Equipment

ppm parts per million (10-6)

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REI Restricted Entry Intervals

RQ Risk Quotient

TER Toxicology Exposure Ratio

μg microgram

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Appendix B: Bibliography

EFSA (2014). "EFSA Guidance Document for evaluating laboratory and field dissipation studies to

obtain DegT50 values of active substances of plant protection products and transformation products

of these active substances in soil " EFSA Journal 12(5): 3662.

Probs, M. B., N, Lentzen-Godding, A., Schulz, R. (2005). "Scenario-based simulation of runoff-related

pesticide entries into small streams on a landscape level. Ecotoxicology and Environmental safety."

Ecotoxicology and Environmental safety 62: 145-159.

APP203305 Scorpio Ornamental Fungicide - EPA...Updated science memo for application to import or manufacture Scorpio Ornamental Fungicide for release (APP203305) April 2018 The PEC

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