INTERSESSIONAL MEETING OF THE
INTERGOVERNMENTAL GROUP ON TEA
Mombasa, Kenya, 18 – 19 July 2011
REPORT OF THE WORKING GROUP ON
MRLs ON TEA BREW
I.
INTRODUCTION
1.
At the 19th Session of the IGG on Tea, which was held in New Delhi, India, 12-14 May 2010,
the Meeting further discussed the importance on the estimation of pesticide residue contents in tea
brew which is consumed via drinking the tea infusion by human beings, and the possibility in the
establishment of MRL of pesticides in tea in consulting with the pesticide residue level in tea brew.
II.
BACKGROUND
2.
Since the establishment of WG on the pesticide residue in tea brew in 2008, the following
activities were conducted


A ring test including black tea, green tea samples sprayed with three pesticides of different
water solubility (Bifenthrin, Imidacloprid and Dimethoate) were analyzed in the lab in four
countries (China, India, SriLanka, Bangladash). The residue levels of these three pesticides in
black tea, green tea and tea infusion were analyzed and compared.
The methodology for measuring the residues of three pesticides in the dry tea and tea brew
were established. Research indicated that the methodology for measuring the polar pesticides
was somewhat different from that for non-polar pesticides. It was recommended to add some
water (adding 50-100 percent water in weight basis) in the dry tea with polar pesticides to
improve the recovery of pesticide in dry tea sample.
III.
ACTIVITIES OF THE WORKING GROUP
3.
According to the investigation conducted in China, India and Japan since 1988, the transfer
rate of pesticide from dry tea to tea infusion of 34 pesticides during the tea brewing process was
conducted. Results clearly showed that the transfer rate of different pesticides during the brewing
process was correlated to the water solubility of pesticides (Attached Table).
4.
A policy issue on the establishment of MRLs of pesticide residue in dry tea was recommended
to prepare for submission to FAO regulatory authority.
5.
According to this decision, a policy issue was prepared by the Working Group on tea brew in
2010.After the revision by the China, India, USA, Canada and UK delegates, this document was
submitted to CCPR Secretariat by IGG Secretariat and China delegation, and disseminate to the
delegates of 43rd CCPR as the 13(c) document (Attached document).
6.
A Side-Bar Meeting was organized by the Delegation of USA, Canada and UK during the 43rd
CCPR Meeting period at April 5 evening at Beijing, China. Mr Joseph Simrany (USA), Mr Louise
Roberge (Canada), Ms Katie Donnelly (UK) and Prof. Chen (China) gave a presentation separately
during the meeting. Around 80 people from 10 countries attended. The significance of establishing the
MRLs of pesticide residue in dry tea in consulting with the transfer rate from dry tea to tea brew was
discussed.
7.
A formal presentation was made by Mr Joseph Simrany to the full Codex Delegation of
approximately 400 persons on Thursday, 7 April 2011 (copy attached). Codex did not disapprove or
approve the proposal outright but they did say that they would certainly take into consideration the
transfer rate when establishing tolerances for tea. They were reluctant to change the way they test for
residues on all commodities; i.e. on the raw material as it is traded. We argued that we were not
seeking a change to their policy simply a change in how the tea samples were prepared before they
were assessed for the presence of chemical residues. They indicated that the science supporting the
proposal “was weak”. Further progress with Codex will necessitate more fully addressing their
objections.
IV.
CONCLUSIONS
8.
After the Action Plan of the Working Group on tea brew, the importance of transfer rate of
pesticide residue from dry tea to tea infusion in the establishment of MRL standards of pesticide was
recognized by more and more persons in world tea industry. The following Action Plan is
recommended by the WG on Tea Brew.
9.
Conduct the investigation of establishing the safe level of various pesticides, especially the
highly water soluble pesticides, based on the risk analysis of intake via tea drinking.
10.
Recommend to minimizing the application of highly water soluble pesticides in the world tea
industry for the safety of world tea drinkers.
11.
Carrying out the alternative Pest management System to replace those proving to be
unsustainable in the world tea production.
Transfer rate of pesticide residue from dry tea to tea infusion
Pesticide
Transfer
rate (%)
Water solubility
(mg/L)
Lg Kow
Published
year
Author
DDT
<1
0.0012 (25℃)
5.8
1980
Chen ZM et al
Deltamethrin
<1
0.002 (25℃)
6.2
1983
Chen ZM et al
Deltamethrin
0.14-0.46
2009
Manikanadan N
Fenpropathrin
0.14-0.65
0.014
6
1986
Chen ZM et al
Hexaconazole
0.14-1.85
17
3.9
2009
Manikanadan N et al
Fenpropathrin
0.14-2.63
0.014
6
2009
Manikanadan N
Fenvalerate
1.18-2.44
0.002
6.2
1985
Chen ZM et al
Cypermethrin
1.4-2.1
0.019
4.6
1986
Chen ZM et al
Endosulfan
1.67-2.05
0.3
4.76
2009
Manikanadan N et al
Endosulfan
1.8
3.83
2001
S. Jaggi et al
Endosulfan
7.72-8.74
0.13
4.51
1998
Chen ZM et al
Dicofol
2.2
0
4.28
1988
Chen ZM et al
Dicofol
0.1
2001
S Jaggi et al
Ethion
2.25-2.5
2
4.28
2009
Manikanadan N et al
Fenazaquin
2.80-22.40
0.007
5.51
2004
V Kumar et al
Permethrin
3.9-4.67
0.07
6.1
1981
Chen ZM et al
Bifenthrin
4.2-4.6
0.1
6
1986
Chen ZM et al
Bifenthrin
1.5-14
2005
DK Tewary et al
Isoxathion
<5
0.001
1989
Nagayama T et al
Prothiophos
<5
0.001
1989
Nagayama T et al
BHC
5-8
10(20℃)
6.5
1980
Chen ZM et al
Propinconazole
5.11
110
2.8
Pyridaben
6.68
0.1(25℃)
6.37
1997
Chen ZM et al
Chlorpyrifos
9.12
2
5.11
2009
Manikanadan N et al
Pesticide
Transfer
rate (%)
Water solubility
(mg/L)
Lg Kow
Published
year
Author
Chlorpyrifos
11
1.4
4.7
2007
A Ozbey et al
Pirimiphos-ethyl
13.0
2.3
5
2007
A Ozbey et al
Monocrotophos
19.78
1000
0.6
2001
S. Jaggi et al
Quinalphos
21.4-44.5
17.8 (23℃)
3.08
1986
Chen ZM et al
Quinalphos
8.04
2001
S. Jaggi et al
Quinalphos
9.2
2009
Manikanadan N et al
Pesticide
Transfer
rate (%)
Water solubility
(mg/L)
Lg Kow
Year
Published
Author
Proparigate
23.6-40
0.215
5.7
2005
Triazophos
24.0
39
3.55
2010
Chen ZM et al
Triazophos
29.06
39
3.55
2007
Wu XY et al
Parathion-methyl
25.8
55
3.43
2001
S. Jaggi et al
Imidacloprid
28.0
510
0.57
2010
Chen ZM et al
Imidacloprid
29.2-42.0
610
0.57
2008
M Gupta et al
phosphamidon
33.3
1000
0.7
2001
S. Jaggi et al
Chlorfenvinphos-E
45
145
3.23
1989
Nagayama T et al
Malathion
48.8-86.3
145 (23℃)
2.19
1980
Chen ZM et al
Malathion
62.0
145
2.75
2007
A Ozbey et al
Chlorfenvinphos-Z
52
145
3.1
1989
Nagayama T et al
Acetamiprid
5.6-5.7
4200
0.8
2008
M Gupta et al
Acetamiprid
68-85
4200
2010
Chen ZM et al
Fenitrothrin
69.7-75.6
30 (25℃)
1991
Chen ZM et al
Fenitrothion
48
1989
Nagayama T et al
Methidathion
83
250
2.2
1989
Nagayama T et al
Dimethoate
97.5-98.3
25000 (20℃)
0.6
1991
Chen ZM et al
Dimethoate
91
23300
0.7
2007
A Ozbey et al
21
3.38
3.43
V Kumar et al
A Review of Pesticide
Tolerances for Tea in the USA
Presented By
Joe Simrany, President
Tea Association of the USA, Inc.
April 1, 2011
Background


The Tea Association of the USA was formed in 1899
to protect the Tea Industry in the USA from harm
For the last 112 years it has performed its duties well
by defending the industry against:






Terrorism threats
False allegations of bacterial contamination
Government inquires re improprities
Harmful publicity
Residues in tea
Incorrect or irresponsible company claims
Major Current Projects
Pesticide Residues in Tea

History





For nearly 100 years the USA Tea Industry had its
own law regulating the importation of tea
It was in place for nearly 100 years, formed in
1897 and abolished by the Clinton Administration
in 1996
It insulated the tea industry from virtually all other
government regulatory involvement
A sample of every shipment of tea coming into the
country had to pass federal inspection
The Tea Act of 1897 was almost entirely funded
by industry
Major Current Projects –Details
Pesticide Residues in Tea

Industry Position Post Tea Act




For the next 12 years, tea was only infrequently
inspected by the FDA with no major detentions
There was also a mistaken perception that in the
absence of a specific pesticide registration for tea
that the FDA would default to a similar vegetable
Consequently, there was little reason for the
industry to take aggressive actions to update the
handful of pesticide MRL’s that were currently in
place for decades
Cost of registering new pesticides was also
certainly a contributing factor to maintaining the
status quo
Major Current Projects –Details
Pesticide Residues in Tea

2008 Incident



In March 2008 the Tea Association was asked by
one of its importers to intercede with the FDA who
had detained 30 containers of tea because of
illegal pesticide residues
The number of detained containers quickly rose to
over 40; essentially stopping the flow of tea into
the country
The earliest detention concerned the presence of
“high” levels of lead with all the others concerning
pesticide levels
Major Current Projects –Details
Pesticide Residues in Tea

2008 Incident


3 pesticides were detected; Lamdacyhalothrin, Bifenthrin, and Fenvalerate
The Association commissioned a
scientific study demonstrating that the 3
pesticides posed zero risk to human
health
Major Current Projects –Details
Pesticide Residues in Tea

Immediate Penalties Imposed


Despite reaching agreement with the
FDA, They rejected the 30 containers of
tea that had already been inspected but
released the 10 containers that had
been detained but not yet inspected
We argued that the 30 containers posed
zero risk to health and the FDA
responded that it was a matter of law
not public safety
Major Current Projects –Details
Pesticide Residues in Tea

Agreement Reached with the FDA


The Tea Association met with FDA
officials & over the ensuing weeks
worked out an agreement that they
would use enforcement discretion
provided we put forth good faith efforts
to fix the problems
Our legal bill for 2008 exceeded $80,000
Major Current Projects –Details
Pesticide Residues in Tea

Subsequent Actions Taken




Faced with extraordinarily high legal, research,
and registration fees, the Tea Association
explored all alternative actions.
The Association put together an international
team of experts and met frequently in person
and electronically
At the suggestion of Dr. Richard Lane, we met
with officials from Crop Life America; a trade
association of pesticide manufacturers at their
Washington DC headquarters
At that meeting an organization called IR4 was
identified as being potentially helpful
Major Current Projects –Details
Pesticide Residues in Tea

Subsequent Actions Taken


The Tea Association met with representatives
of IR4 during which we learned that we might
qualify for their help if tea was domestically
grown
We informed them of the RC Bigelow
plantation which they thought could work
Major Current Projects –Details
Pesticide Residues in Tea

Global Involvement



Even prior to the 2008 incident, in anticipation of
an eventual pesticide problem in the USA, the
Tea Association took a leadership role at several
international forums including the International
Tea Committee in London, specific tea producing
country conventions, and at the FAO IGG
meetings (a committee of the UN)
The objective being to raise awareness about
pesticides, to steer producers towards “better”
chemicals and to try to harmonize MRL’s globally
This action helped immensely with our current
situation by giving us access to much data
Rationale for Pesticide
Harmonization

At that time our overall goal was to harmonize
pesticide MRL’s for all countries to the extent possible
because:





Consumer safety does not recognize country boundaries
Optimizing consumer safety using the latest technology and
& applying globally
Simplify pesticide practices for all producers
Reduce/eliminate the need for redundant toxicology/field
tests by using a single source
Encourage pesticide manufacturers to take on a greater role
in the registration process
Rationale for Pesticide
Harmonization

We quickly learned that harmonization
of pesticides between countries was
incredibly challenging because:



Different regulatory agencies have
different ways of evaluating risk
Consumption patterns varied widely
between countries
Countries were reluctant to release
“proprietary” test data
Current Pesticide Standards
for Tea





Vary by country
Many are outdated
Many are out of
patent
Do not reflect
current practices in
the USA
Many do not
adequately consider
transference from
the leaf to the cup



Are constantly
changing & can be
confusing to the
producing countries
Are difficult to
communicate to
farmers
Require redundant &
costly testing in
each country
Pesticides Currently Authorized
for Use on Tea in the USA





Acetamiprid
Dicofol
Propargite
Pyriproxyfen
Glyphosate


50 ppm
50 ppm
10 ppm
.02 ppm
Tea – dried 1 ppm
Tea – instant 7.0 ppm
Chlorfenapyr .1 ppm
 Endolsulfan
24 ppm*
 Carfentrazone .1 ppm
*Combined residues of several pesticides

Pending Pesticide Registrations in
the USA

Status of Agreement with the FDA/EPA






Enforcement discretion is generally holding.
We currently have 4 pesticide registrations
pending approval with the EPA, each submitted
by IR4:
Cypermetthrin
Bifenthrin
L-cyhalothrin
Fenpropathrin)
Other Pending Pesticide
Registrations for tea in the US
Other pesticides pending submission to
IR-4 are:
Buprofezin
Propicanazole
Tolfenpyrad
Fenproximate
Clothianidin
Etoxazole
Major Current Projects –Details
Pesticide Residues in Tea

Next Steps





Continue working with IR4 & the EPA to
minimize costs by combining with other
registrants
Identify priority chemicals
Communicate to producing countries those
pesticides that should immediately discontinue
Encourage producers to use water insoluble
chemicals over the short term
Work with pesticide manufacturers to develop
better pesticides for use on tea and to register
those pesticides in the USA
Codex Initiative


As part of a short to mid-term strategy,
if the proposal is approved by Codex,
we will make recommendations to the
tea producing countries to use the best
water insoluble pesticides available to
them
Also, we will move to register those
pesticides on a priority basis with our
regulatory agencies
Codex Initiative

Our longer term goal is to encourage
the producing countries to use the more
environmentally friendly water soluble
pesticides but it will take several years
before the pesticides will be in widespead use by the Tea Producers.