Goji Berries – A Natural Fruit? Pesticide Residues in Dried Goji

Goji Berries – A Natural Fruit?
Pesticide Residues in Dried Goji Berries 2009/2010
Hacker K, Bauer N, Schüle E, Wieland M, Scherbaum E
E-Mail: [email protected]
92%
Acetamip rid
INTRODUCTION
Advertisements promise: eat a handful of goji berries
daily and you’ll stay fit, healthy and young. This so
called „anti-aging berry“ from Asia, also known as the
wolfberry, has become a trend in western countries.
In Europe the red berries are usually sold as dried
fruit or goji juice. In some cases they are claimed to
be “natural” or “wild-harvested”, which gives the
consumer the impression that they grow naturally
without the use of chemical synthetic pesticides.
81%
Cyp erm eth rin *
73%
P yrid a b en
65%
Imid aclop rid
65%
2,4-D
62%
Triad ime fon /triad imen ol*
62%
Ch lorp yrifos
54%
Th iop h a n ate -me th yl
50%
Lam b d a-Cyh aloth rin
50%
Clofe n tez in e
46%
Carb ofu ran *
42%
Fe n -/e s fen vale rate
38%
P rop arg ite
35%
Dife n oc on az ole
27%
Tria zop h os
23%
Myclob u tan il
ANALYSIS
Pesticides
detected in less
than 20% of the
samples
Amitraz*
Hexaconazole
Propiconazole
Aldicarb*
Chlorothalonil
Endosulfan*
Fenpropathrin
Fosthiazate
MCPA
Tetradifon
Pendimethalin
Dicofol
Dimethoate*
Haloxyfop
Isoprothiolane
Mepanipyrim
Methomyl*
Profenofos
Propamocarb
Tebuconazole
Triazamate
73%
Ca rb en d az im*
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
FREQUENCY OF DETECTION
Since MRLs are only set for the fresh berries, a
processing factor of 5 was used for calculating the
residue values, taking into account the effect of
drying on the residue concentration.
RESULTS
In 2010, hardly any change in the residue situation
was noticed. In total, 38 different pesticides were
found. On average, 11 pesticide residues per
sample were detected (see Figures 1 and 2).
Among the 26 samples, two were labelled as
organic. These met the legal provisions - e.g. only
residues <0.01 mg/kg (action level for organic
produce) were detected.
Figure 1 Detection frequency of pesticides; *sum parameter
NUMBER OF SAMPLES
5
conventional
4
organic
3
4
2
1
3
3
2
1
1
1
1
2
3
2
2
1
1
1
1
18
19
0
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
NUMBER OF PESTICIDE RESIDUES PER SAMPLE
Figure 2 Number of pesticide residues detected per sample
LEGAL AMENDMENTS
In the latest amendment to Annex I of Regulation (EC)
No. 396/2005 goji berries are to be grouped with
tomatoes as “other products included in the definition to
which the same MRL applies” – hence, the MRL for
acetamiprid will change from 0.01 mg/kg to 0.1 mg/kg.
Thus, when applying the new MRL to our 1020 survey
data, only 5 samples would have an acetamiprid MRL
violation compared to 20 samples now (see Figure 3).
A C E T A M IP R ID R E S ID U E [m g /k g ]
In 2009, CVUA Stuttgart analyzed 14 dried goji berry
(Lycium barbarum and L. Chinense) samples for
residues of more than 550 different pesticides and
metabolites using the QuEChERS method [1]. Given
that all the samples surveyed in 2009 (including a
sample labelled as organic) contained residues
above the MRL for acetamiprid, 26 dried berry
samples
(mostly originating from China) were
analyzed in the first half of 2010 to see whether the
residue situation had improved.
0,140
0,120
future MRL
0,100
0,080
0,060
0,040
0,020
current MRL
0,000
1
However, only two of the 24 conventionally grown
samples met the legal requirements. Miscellaneous
samples contained more than one legal violation:
in 83% of the conventionally grown samples
MRL violations were found (20 x acetamiprid,
1x chlorothalonil, 1x propargite)
in 4 samples claims such as “wild-harvested”,
“natural” or “residue-free” were misleading to the
consumer due to the presence of extensive amounts
of pesticide residues
in 6 samples the labelling was incorrect (1x nonproven health claim, 4x preservation with sulphites
was not labelled, 1x nutrition labelling of claimed
vitamins was missing)
in one case forbidden irradiation of the berries
was detected
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
SAMPLES
Figure 3 Acetamiprid residues in dried goji berries (values
referring to fresh berries); Samples No. 10 and 20 were organic
SUMMARY
Conventionally grown goji berries are often treated
extensively with pesticides, even though sometimes
claimed otherwise. Only 6 out of 26 samples met the
current legal provisions set for pesticide residues.
However, due to amendments to Annex I Reg. (EC) No.
396/2005, MRL violations in goji berries will probably be
less in future.
LITERATURE
[1] CEN/TC 275 prEN 15662:2008; Foods of plant origin - Determination of pesticide residues using
GC-MS and/or LC-MS/MS following acetonirile extraction/partitioning and cleanup by dispersive SPE
[2] BfR-Datensammlung zu Verarbeitungsfaktoren für Pflanzenschutzmittel-Rückstände
www.bfr.bund.de/cd/10196
PM 037
EPRW 2010