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Fragrance Ingredients and Dermal Sensitization Anne Marie Api, PhD Vice President, Human Health Sciences Personal Care Products Council Safety Seminar October 4, 2012
Fragrance Ingredients and
Dermal Sensitization
Anne Marie Api, PhD
Vice President, Human Health Sciences
Personal Care Products Council
Safety Seminar
October 4, 2012
Fragrance Ingredient Safety
I
F
R
A Code of Practice & Standards
Member Companies
R
I
F
M
Expert
Panel
Research & Testing
Safety Evaluations
2 Api Oct 2012
Human Health Research:
Fragrance Allergy
Autoxidation (2003 – 2008) Investigate the fundamental scientific basis of the
autoxidation of 4 important structurally related fragrance
ingredients and one essential oil
Elicitation Threshold – Eugenol (2012) To determine the threshold for elicitation of contact allergy
using two methods - patch testing and repeated open
application testing
Epidemiology (2006-2011) Determine the prevalence of fragrance allergy in the general
population
Supplying Patch Test Materials Supply fragrance ingredients to patch test suppliers free of
charge to ensure that good quality commercial samples are
tested.
Other Diagnostic Patch Tests Work with dermatologists to monitor the implementation of
the QRA 3 Api Oct 2012
Autoxidation
2007- 2009, peroxide values were determined using the
FMA method for 875 freshly manufactured fragrances to be
used in various consumer products. The sum of d-
limonene plus linalool concentration ranged from 0 to
89.67%.
All had peroxide values< 15 mmol/liter
34 hydroalcoholic perfume products were retrieved from
retail establishments (20 women’s and 14 men’s products).
None of the hydroalcoholic perfumes retrieved from retail
establishments had peroxide values > 5 mmol/liter
80 hydroalcoholic fragrance products were retrieved from
end-use consumers. These had been opened and used by
the consumers for variable periods of time ranging from a
few months to 5 years
None of the fragrances retrieved from consumers had
peroxide values exceeding 10 mmol/l
4 Api Oct 2012
Elicitation Threshold Studies
Elicitation Threshold – Eugenol (planned 2012)
To determine the threshold for elicitation of contact
allergy using two methods - patch testing and repeated
open application testing
Pilot 1 - Does the New Standard for Eugenol Designed
to Protect Against Contact Sensitization Protect Those
Sensitized From Elicitation of the Reaction?
Svedman et al., Dermatitis 23(1):32-38, 2012
Pilot 2 - A pilot study aimed at finding a suitable
eugenol concentration for a leave-on product for use in
a repeated open application test.
Svedman et al., Contact Dermatitis 66(3), 132-139, 2012
Further Elicitation Threshold studies on other
weak sensitizers used in fragrances
5 Api Oct 2012
EDEN Epidemiology Study
Questionnaire Development
Reviewed by Dr. S. Chen,
Emory University
Validation
Reproducibility
Patch Test Procedures
2005-2006
Phase I
Validation
600 subjects (100/center)
Statistical analyses
• All subjects patch tested
Study modalities evaluation
Definition of sampling procedures and subject
recruitment
6th center added (Portugal) by RIFM request afterwards
2007-2008
Phase II
Pilot Study
Protocol reviewed & approved by independent
epidemiologist, Dr. H Rockette, Univ. of
Pittsburgh
RIFM Board recommendation: full study extended over 3
yrs to defer costs
EDEN delayed in getting all data; 2
centers started later
EDEN needed time to consolidate & analyze all data in database
• >12,000 subjects
• >3,000 patch tested
Each patch test center was monitored by
expert in patch testing - Dr. M. Isaksson, Skane University
Hospital
Each center was monitored by independent
epidemiologist, Dr. B.M Zaadstra
2008-2011 Full
Study
Epidemiology: Instrument
Original and landmark study
Rigorous scientific quality
Patch testing- 50 materials
29 materials - European Standard
Series
20 “fragrance materials”
Standardization of patch testing;
unprecedented calibration
performed
Training – video & classes for patch
testing
Controlled commercial grade
samples
Blind comparison patch test &
history
Website established
Baseline data particularly for
introduction of QRA
7
Api Oct 2012
Epidemiology: Instrument
published 2010 (peer-reviewed)
8 Api Oct 2012
QRA: Why?
Goal or ideal state is to eliminate fragrance allergy in the general population
Core strategy for primary prevention of dermal sensitization to fragrance ingredients in consumer products
Prevent induction of sensitization to fragrance ingredients (primary prevention) more effectively than we have in the past
Lead with a scientifically
rigorous strategy 9 Api Oct 2012
Peer review: an essential part of scientific publication
QRA paper represents recognition of the approach by the scientific community
Regulatory , Toxicology & Pharmacology
Special Issue Oct. 2008
Dermal Sensitization QRA for Fragrance Ingredients
7 manuscripts including
Api et al. - QRA method
McNamee et al. - HRIPT scientific review
Politano & Api - HRIPT RIFM method
Kimber et al. - Dose Metric
QRA paper is
among the 10 most
cited papers in
Reg. Tox. & Pharm.
for 2007-2008
10 Api Oct 2012
Acceptable Exposure Level =
(RfD or AEL)
NOEL
Uncertainty Factor (UF)
Acceptable Exposure Level (RfD or
AEL) Estimate of a daily exposure to an
agent that is assumed to be without a
health impact in the human population
Risk Assessment –
General Principles
Api Oct 2012 11
QRA For Dermal Sensitization
Fragrance Ingredients
Api Oct 2012 12
Step 1: Hazard Identification
Determine potential (hazard) to induce sensitization from:
Pre-clinical studies e.g. Guinea-Pig Test,
Local Lymph Node Assay (LLNA)
Human data (historical)
Structure based predictive approach
Application to induction of skin sensitization - a threshold phenomenon
QRA For Dermal Sensitization
Fragrance Ingredients
Step 2: Dose response
assessment:
Takes into account key factors:
Determine the No-Expected-
Sensitization Induction-Level (NESIL)
based on the Weight of Evidence
(WoE)
Calculate Sensitization Assessment
Factor (SAF)
13 Api Oct 2012
SAF Definition
Extrapolation from controlled experimental situation to real life exposure scenarios Defined more effectively the areas of
assessment in extrapolating from experimental to real-life scenarios
Use of WoE approach to determine values for the defined areas of assessment
Decisions supported by peer-reviewed scientific literature references
Three areas of extrapolation
Inter-individual susceptibility
Matrix effects
Use considerations 14 Api Oct 2012
Inter-individual Variability (Age, gender, ethnicity, inherent dermal barrier and
genetic effects)
Vehicle or Product Matrix Effects (e.g. presence of irritants, penetration enhancers)
Use Considerations (Site of contact, barrier function, occlusion)
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1 10 3
1 10 3
SAF Summary
Api Oct 2012 15
SAF Examples
Product Inter-Indiv. Variation
Matrix
Effects
Use
Considerations
Total SAF
Deodorant SAF = 10
Same as general toxicology
SAF = 3
Product Matrix different from experimental conditions; may contain irritating actives
SAF = 10
Area = underarm; skin easily irritated, highly follicular; area may be shaved. Occlusion similar to experimental conditions33-36
300
Shampoo SAF = 10 Same as general toxicology
SAF = 3
Product Matrix very different from experimental conditions; may contain irritating ingredients
SAF = 3
Area is the head; highly follicular; scalp is more permeable33,49
100
QRA For Dermal Sensitization
Fragrance Ingredients
Step 3: Exposure
Dose metric: expressed in Dose/Area
Understand consumer exposure
expressed as product categories
How consumers are exposed: amount,
duration and frequency
17 Api Oct 2012
62.5mg DNCB
62.5mg DNCB
Sensitization Rate
1.8 cm2 Site
7.1 cm2 Site
85%
8%
Reviewed in Contact Dermatitis 1992, 27:281-286
Influence of Area Exposed
on Sensitization
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Acceptable
Exposure Level (AEL)
WoE NESIL
Sensitization Assessment Factor (SAF)
Comparison of Acceptable Exposure Levels (AEL) to calculated Consumer Exposure Level (CEL)
AEL ≥ CEL to be Acceptable
Step 4: Risk Characterization
Acceptable Exposure Levels (AELs) to fragrance ingredients that are dermal sensitizers can be determined in specific real life consumer product types
=
QRA For Dermal Sensitization
Fragrance Ingredients
Api Oct 2012 19
QRA Dermal Sensitization Citral
Api Oct 2012 20
Weight of Evidence NESIL Guinea-pig data – weak sensitizer [14]
Local Lymph Node Assay
EC3 = 1414 µg/cm2 [11]
Human data
HRIPT NOEL = 1400 µg/cm2
WoE NESIL = 1400 µg/cm2
SAF Considerations
Inter-individual variability
Product matrix differences
Variations in use patterns
Hydroalcoholic Unshaved SAF is 100
Deo/AP SAF is 300
Exposure Consumer exposure to:
Hydroalcoholic (unshaved skin)
= 2.2 mg/cm2
AEL = 1400/100
= 14.0 µg/cm2
AEL/CEL (14.0 ug/cm2 x 0.001
mg/µg) 2.2 mg/cm2/day =
0.006
AEL≥CEL 0.6%
DEO/AP = 9.1 mg/cm2
AEL = 1400/300 = 4.7 µg/cm2
AEL/CEL = 0.0005
AEL≥CEL 0.05%
QRA Dermal Sensitization: Citral In Hydroalcoholic Unshaved Skin - Induction
21 Api Oct 2012
0.01 0. 1 1.0 10 100 1000 10,000
Citral Level - log μg/cm2
1.7%
37μg/cm2
CEL 14
μg/cm2 AEL
1400 μg/cm2
WoE NESIL
0.6%
13 μg/cm2
CEL
AEL/CEL
Unacceptable
AEL/CEL
Acceptable
SAF = 100
QRA Dermal Sensitization Citral In Solid AP - Induction
Api Oct 2012 22
0.01 0. 1 1.0 10 100 1000 10,000
Citral Level - log μg/cm2
SAF = 300
0.05%
4.3 μg/cm2
CEL
4.7 μg/cm2
AEL
1400 μg/cm2
Woe NESIL
AEL/CEL
Acceptable
IFRA Product Categories
Based On QRA
IFRA Category Examples of Products
Category 1 Lip Products, Toys
Category 2 Deodorants/Antiperspirants
Category 3 Hydroalcoholic Products for Shaved Skin, Eye Products, Men’s
Facial Cream & Balms, Tampons
Category 4 Hydroalcoholic Products for Unshaved Skin, Hair Styling Aids &
Sprays, Body Creams
Category 5 Women’s Facial Cream/Facial Make-up/ Wipes or Refreshing
Tissue, Hand Cream, Facial Masks
Category 6 Mouthwash, Toothpaste
Category 7 Intimate Wipes, Baby Wipes
Category 8 Make-up Remover, Hair Styling Aids Non-Spray, Nail Care
Category 9 Shampoo, Rinse-Off Conditioners, Bar Soap, Feminine Hygiene
Pads & Liners, Other Aerosols (including air fresheners sprays but
not including deodorant/antiperspirants, hair styling aids spray)
Category 10 Detergents, Hard Surface Cleaners, Diapers
Category 11 All Non-Skin or incidental skin contact products
IFRA Product Categories
Based On QRA
IFRA
Category SAF
Category
Consumer
Exposure
mg/cm2/day
Product Type
Designating IFRA
Category
Maximum Pragmatic
Level
Category 1 300 11.7 Lipstick AEL derived from QRA
Category 2 300 9.1 Solid Antiperspirant AEL derived from QRA
Category 3 300 2.2 Aftershave AEL derived from QRA
Category 4 100 2.2 Perfume AEL derived from QRA
Category 5 100 4.2 Hand Cream AEL derived from QRA
Category 6 100 1.4 Toothpaste AEL derived from QRA
Category 7 300 4.4 Intimate Wipes AEL derived from QRA
Category 8 100 1.0 Hair Styling Aids Max conc. ≤2%
Category 9 100 0.2 Conditioners, Rinse-Off Max conc. ≤5%
Category 10 100 0.1 Hard Surface Cleaners Max conc. ≤2.5%
Category 11 10 0.00033 Candles
SAF Product Type
Consumer
Exposure
Level
mg/cm2/day
IFRA
Category 5
Consumer
Exposure
100 Facial Cream/
Make-up 3.17
4.2
100 Hand Cream 4.2
QRA Dermal Sensitization: Does It Work?
Evidence of proven effectiveness for other materials
Since 2006, >100 materials have IFRA Standards based on the QRA dermal sensitization
Need to build evidence in fragrance ingredients Cinnamic aldehyde
Citral
Isoeugenol
Clinical
Reports
RA
Risk
Mgmt
25 Api Oct 2012
QRA Dermal Sensitization: Does it
work?
Fragrance
Ingredient
Industry Survey or
Limit
Prior to QRA-based
Standard
QRA –based Limit
Cinnamic
Aldehyde Skin level: 0.05% Deo/AP: 0.02%
Citral
Hydroalcoholics: 1.7% Hydroalcoholics: 0.6%
Deo/AP: 0.05% Deo/AP: 0.05%
Isoeugenol Skin level: 0.2% Hydroalcoholics: 0.02%
26 Api Oct 2012
Database U. Hospital Leuven
2000-2007
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Fragrance
Ingredient Product Type
Positive Patch Test
Reactions to Product
Confirmed & Not Confirmed
Cinnamic
Aldehyde
Deodorant 4
Intimate Hygiene Wipes 1
Hair Care 1
Citral
Hydroalcoholic 9
Skin Care 2
Deodorant 1
Isoeugenol
Hydroalcoholic 14
Skin Care 4
Deodorant 2
Hair Dye 1
Api et al, Dermatitis, 21(4): 207-213, 2010
QRA Implementation Status
40th Amendment May 2006 – 4 materials
42nd Amendment May 2007 – 28 Standards on 51
materials
43rd Amendment July 2008 - 18 Standards on 31
materials
44th Amendment May 2009 – 12 Standards
45th Amendment June 2010 – 4 materials
46th Amendment June 2011 – 6 materials
only 2 existing Standards remain to be converted to a
QRA based Standard
47th Amendment Spring 2013
Expert Panel: Compliance with IFRA Standards
28 Api Oct 2012
IFRA/RIFM INFORMATION BOOKLET VERSION 6.0 (July 2011)
How new and existing IFRA Standards will
be set
Definition of the IFRA product categories
Changes in product categorization, for
example
Product types not previously included
Re-categorization (new/updated exposure)
Definition of the IFRA product categories
Guidance on preparing IFRA Certificates
29 Api Oct 2012
Benefits of QRA Method
Lead with a scientifically robust strategy
Major improvement over the former approach addresses elements of exposure-based risk
assessment - unique to induction of dermal sensitization
consistent with the principles of general toxicology risk assessment
Risk management strategies 10 different product categories for skin contact
products.
Category 11 - non-skin or incidental skin contact products
Exposure - key element of category determination enables maintenance of relevant exposure and
therefore safety
Categories provide greater flexibility to the perfumer
30 Api Oct 2012
QRA Recognition
An important step forward as scientific
method
Refinements will occur as new data
becomes available
Full trust from the fragrance industry
and its customers regarding application
and use of the QRA method
Industry will continue implementation
and validation
SCCP opinion of June 2008 – moderately
optimistic
Methodology used by Australian
regulators
Interest from US FDA and US EPA
31 Api Oct 2012
Overview of The Changes in Human
Health Safety Assessment Paradigm
Focus is on individual substance Safety Assessments
Key endpoints to be assessed were identified
Prioritized materials will be assessed using a series of
tiered data relevant to each endpoint:
Available data on the material itself and/or closely related
materials (new groupings)
Screening level toxicity data
Higher tier toxicity studies
Assessments will result in acceptable use levels for each
material (exact form of publication to be determined but it
is envisioned various forms of safety assessments will
result )
Assessment program underpinned by foundation science
initiatives
32 Api Oct 2012
Human Health Science Program
Foundation Science
Emerging Issues
Exposure Methodologies
In Silico Models
Alternate Test Methodologies
Human Health Safety Assessment (individual material assessment)
Sensitization
Genotoxicity
Phototoxicity
Repeat Dose
Reproduction
Respiratory Interrelated streams
– Robust but flexible substance assessment program (ability to adapt to new learnings)
– Leading knowledge development for the safety assessment of fragrance ingredients
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Exposu r e
Api Oct 2012
Human Health Criteria Document I
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Published 2000
Prioritized Materials
• Volume of Use
• Exposure
• Structural Alerts
Helps direct Human
Health research &
testing program and
group summary
Api Oct 2012
Human Health Criteria Document II
Written to use the best science available to
support the safety of a fragrance material;
the studies to do this will take regulatory requirements
into consideration but will not be specifically designed
to ensure the acceptance of a fragrance material for a
specific regulatory approval
Purpose of the criteria document
external audience is important;
roadmap to how a safety assessment is completed;
need document for internal industry audience as an
overview of the (new) safety process;
for industry members to use to safety assess their
substances and for external audience
35 Api Oct 2012
Human Health Criteria Document II
Intelligent Testing Strategy: Need to achieve an
appropriate balance between the level of testing
required for all ingredients versus the development of
criteria which clearly identifies the need for endpoint
specific testing
Integrate latest tools
TTC on all endpoints
QSARs/SARs
Screening assays to increase our understanding of key
endpoints & provide a biological anchor for QSARs & material
relationships
Improved grouping & read-across approaches to ensure a
more sophisticated and scientifically credible way of
extrapolating test results from one substance to another
Will be published in peer reviewed scientific journal
36 Api Oct 2012
Human Health Criteria Document II
Threshold for Toxicological Concern Conservative first level approach in the absence of
material specific data
Defines daily levels of exposure (thresholds) to a material
below which there is no expected safety concern
Allows materials to be cleared based only on low
consumer exposure
Read Across –uses common endpoint
data
Physicochemical properties
Toxicity
Metabolism
Exposure
37 Api Oct 2012
RIFM Systemic Aggregate
Exposure to Fragrance Materials
Current Method: Cumulative dermal exposure
from 10 cosmetic products
Modify the current method to include
Oral exposure (toothpaste/mouthwash)
Inhalation from air care products
Indirect oral and inhalation exposure (e.g. oral
exposure from dishwashing products; inhalation
exposure from cleaners)
Aggregate exposure - preferably World Wide but
initially for Europe and North America
The data will also be made available in a software
model which can be used by industry and
regulators
38 Api Oct 2012
RIFM Aggregate Exposure Model –
Products Included
Phase I
Body Lotion (prestige vs.
mass market)
Deodorant/antiperspirants
Face cream
Shampoo
Hair Styling Products
(excluding hair spray)
Hand Cream
Hydroalcoholics
Lipstick
Liquid/Makeup Foundation
Mouthwash
Shower Gel
Toothpaste
Phase II
Liquid hand soap and bar
soap
Inhalation
Air Fresheners
Candles
Hair Spray, Perfume,
Deodorant Spray
Combined Food and
Cosmetics exposure
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These products cover
the major exposure
contribution to
fragrance ingredients
Api Oct 2012
Sensitization Read Across
Approach
A good RA material…
Is in the same reaction mechanistic
domain
Within that domain is similar in reactivity
Has similar hydrophobicity (for some
domains)
40 Api Oct 2012
Sensitization: Applying Read
Across
Comparison with similarly reactive
(&hydrophobic) compounds from same
mechanistic domain
Calculation from Quantitative Mechanism
Model (QMM or a QSAR) when equation is
available and parameters are known for
the target compound
41 Api Oct 2012
Reaction Mechanistic Domains
Michael acceptors – QSAR available, but based
on experimental rate constants
Schiff base formers – QSAR available, based on
structure-derived parameters
Acylating agents – no QSAR, but some SAR
insights
SN2 electrophiles – no general LLNA QSAR,
evidence for dependence on reactivity with
hydrophobicity
42 Api Oct 2012
Intelligent Testing Strategy
LLNAs -Data will be used to build the domain
mechanism in order to help predict other similar
materials
Review continues of predicted reactive materials
Determine materials to help complete
mechanistic domains
Conduct experiments to determine rate constants
Select materials for LLNA testing to show accuracy
of predictability from the rate constants
Select key materials for human testing to confirm
NOEL in humans
43 Api Oct 2012
MORE INFORMATION
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Research Institute for
Fragrance Materials, Inc.
Tel.: +1-201.689.8089
RIFM: www.rifm.org
Api Oct 2012
