Chlorpyrifos Is „OUT“: This Insecticide May No Longer Be Used In the EU
Report from a day in the lab
Ellen Scherbaum, Nadine Korte
It’s news that no news agent or NGO has overlooked: „EU Forbids Insect Killer Chlorpyrifos“ or „Chlorpyrifos: EU-Commission Bans Controversial Insecticide“.
According to an official opinion of the European Food Safety Authority (EFSA) in August 2019, the pesticide chlorpyrifos does not fulfill the criteria legally required for an extention of its authorized use in the European Union. Analyses show: this substance has an affect on human health.
As early as May 2012 American researchers published findings in the Proceedings of the National Academy of Sciences (PNAS) that chlorpyrifos had a detrimental effect on brain development of the unborn [3,4]. But as so often happens, the results were initially doubted, the number of cases so small, the test controversial. Moreover, this substance has been on the market for 60 years and used in a variety of applications.
Chlorpyrifos – A Factsheet
The insecticide and acaricide chlorpyrifos has been used to combat sucking and biting insects in agriculture, against storage pests, against ectoparasites in animal husbandry and in the household.
Chlorpyrifos belongs to the large group of phosphonic acid esters whose insecticide effect is based on an inhibition of the cholinesterase. Its triumphal march began after World War II. In contrast to the organochlorine compounds, which are persistent in the environment, organophosphates degrade very quickly. Although their acute toxicity is high ((E605 (parathion) won some dubious prominence in suicide cases because the inhibition of the cholinesterase especially leads to the cramping of the intestinal tract and can result in death due respiratory paralysis), their chronic toxicity is assessed to be rather low.
In 2014 the European Food Safety Association (EFSA) undertook a new toxicological evaluation of chlorpyrifos and adjusted the acceptable daily intake (ADI, chronic toxicity) as well as the acute reference dosage (ARfD, acute toxicity) downward (see Info Box) [5]. Other adjustments followed: in 2016 and 2018 several maximum residue levels were also lowered.
Info Box
Chlorpyrifos
- Implemented in the mid 1960’s
- Used extensively many years as, e.g. insecticide
- Non-systemic contact, poisonous effect on stomach & respiratory system
- EFSA’s 2014 Acute Reference Dose reduced to 0.005 mg/kg bodyweight
- EFSA’s 2014 Acceptable Daily Intake reduced to 0.001 mg/kg bodyweight and day
- Authorization for use in the EU ended 16 Feb. 2020
- Transitional period for depletion of existing substance expired 18 April 2020
Acute Reference Dose (ARfD)
For the evaluation of pesticides that have a high, acute toxicity and that can cause health damage after just a single or short-term intake, the Acceptable Daily Intake (ADI) value is only appropriate to a limited extent. Since the ADI is derived from long-term studies, it is possibly inadequate as a measure of acute risk from residues in food. Therefore, in addition to the ADI value, a further exposure limit has been established, the so-called acute reference dose (ARfD). The World Health Organization defines the ARfD as the amount of a substance one can consume over the period of one day or in one meal without resulting in any discernible health risk. Other than for the ADI, the ARfD value is not determined for every pesticide, but only for such substances that, when taken in sufficient quantities, could cause damage to one’s health even after just one exposure.
Chlorpyrifos residues – what have we analyzed and what has changed since 2010?
Since 2010 we have analyzed about 20,900 samples of plant-based food from conventional production for residues of chlorpyrifos. Ten percent of the samples were detected with this substance and 51 (0.2 %) exceeded the then maximum valid level.
Citrus fruits were especially found to contain chlorpyrifos residues; 55 % of the analyzed samples contained detectable amounts, followed by spices, tea and nutritional supplements such as moringa.
Table 1 shows an overview of the results.
Food Group | Sub-Group |
No. of Samples
|
% of Samples Positive for Chlorpyrifos
|
Ave. Value mg/kg
|
Max mg/kg
|
Min mg/kg
|
---|---|---|---|---|---|---|
Alcohol-free drinks |
225
|
11 (4.9 %)
|
0.003
|
0.007
|
0.001
|
|
Baked goods |
31
|
-
|
|
|
|
|
Beer & hops/barley |
27
|
1 (3.7 %)
|
0.022
|
|
|
|
Fats & Oils |
145
|
25 (17.2 %)
|
0.019
|
0.079
|
0.001
|
|
Vegetables | Leafy Veg. |
3615
|
182 (5 %)
|
0.12
|
15.9
|
0.001
|
Exotic Veg. |
4
|
-
|
|
|
|
|
Fruiting Veg. |
3525
|
149 (4.2 %)
|
0.025
|
0.84
|
0.001
|
|
Mixed Veg. |
10
|
-
|
|
|
|
|
Sprouting Veg. |
1115
|
52 (4.7 %)
|
0.005
|
0.025
|
0.001
|
|
Root Veg. |
695
|
20 (2.9 %)
|
0.011
|
0.052
|
0.001
|
|
Vegetable products |
526
|
57 (10.8 %)
|
0.13
|
4.4
|
0.001
|
|
Cereals |
229
|
9 (3.9 %)
|
0.007
|
0.018
|
0.002
|
|
Cereal products |
95
|
2 (2.1 %)
|
0.004
|
0.005
|
0.002
|
|
Spices |
159
|
72 ( 45.3 % )
|
0.026
|
0.21
|
0.001
|
|
Legumes, oil seeds, nuts, soy |
273
|
21 (7.7 %)
|
0.041
|
0.19
|
0.008
|
|
Potatoes & starchy plant-parts |
406
|
7 (1.7 %)
|
0.043
|
0.14
|
0.001
|
|
Fruit | Berries |
2795
|
216 (7.7 %)
|
0.016
|
0.31
|
0.001
|
Exotic Fruit |
1680
|
200 (11.9 %)
|
0.012
|
0.15
|
0.001
|
|
Seed Fruit |
997
|
135 (13.5 %)
|
0.042
|
1.1
|
0.001
|
|
Stone Fruit |
1537
|
168 (10.9 %)
|
0.008
|
0.13
|
0.001
|
|
Citrus Fruit |
1195
|
659 (55.1 %)
|
0.041
|
0.62
|
0.001
|
|
Fruit products |
465
|
90 (19.4 %)
|
0.018
|
0.28
|
0.001
|
|
Mushrooms |
500
|
3 (0.6 %)
|
0.002
|
0.003
|
0.001
|
|
Mushroom products |
127
|
32 (25.2 %)
|
0.024
|
0.2
|
0.001
|
|
Baby food |
61
|
1 (1.6 %)
|
0.002
|
|
|
|
Tea |
100
|
38 (38 %)
|
0.028
|
0.23
|
0.005
|
|
Wine & wine products |
251
|
-
|
|
|
|
|
Seasoning sauces |
2*
|
2
|
0.008
|
0.013
|
0.002
|
|
Additives |
2*
|
1
|
0.10
|
|
|
|
Nutritional supplements (Moringa) |
15
|
9 (60 %)
|
0.045
|
0.33
|
0.001
|
|
Other foods |
54
|
2 (3.7 %)
|
0.004
|
0.007
|
0.001
|
|
Cotton clothing |
50
|
-
|
|
|
|
|
Consumer food contact products |
14
|
4 (28.6 %)
|
0.026
|
0.049
|
0.002
|
|
TOTAL Results |
20926
|
2168 (10.4 %)
|
0.037
|
15.9
|
0.001
|
Calculations for country of origin show significant differences. While every second sample from China had chlorpyrifos residues, it has never been used in New Zealand (see Table 2). Only the countries with more than 50 analyzed samples are listed.
Country |
No. of Samples
|
Positive Samples
|
% of Positive Samples
|
---|---|---|---|
China |
258
|
135
|
52.3
|
India | 143 | 43 | 30.1 |
Vietnam | 62 | 18 | 29.0 |
Turkey | 906 | 234 | 25.8 |
Thailand | 124 | 27 | 21.8 |
Argentina | 102 | 22 | 21.6 |
Peru | 242 | 51 | 21.1 |
Spain | 2751 | 553 | 20.1 |
Italy | 1566 | 290 | 18.5 |
Columbia | 100 | 17 | 17.0 |
Chile | 356 | 56 | 15.7 |
Greece | 132 | 20 | 15.2 |
USA | 68 | 9 | 13.2 |
Mexico | 61 | 8 | 13.1 |
Egypt | 161 | 21 | 13.0 |
Israel | 219 | 27 | 12.3 |
Kenya | 107 | 12 | 11.2 |
Brazil | 340 | 35 | 10.3 |
South Africa | 620 | 63 | 10.2 |
Serbia | 55 | 5 | 9.1 |
Ghana | 68 | 5 | 7.4 |
Costa Rica | 234 | 15 | 6.4 |
France | 326 | 14 | 4.3 |
Poland | 197 | 8 | 4.1 |
Morocco | 409 | 15 | 3.7 |
Hungary | 64 | 2 | 3.1 |
Belgium | 199 | 6 | 3.0 |
Germany | 7537 | 80 | 1.1 |
Netherlands | 596 | 3 | 0.5 |
New Zealand | 78 | 0 | 0.0 |
The rate of MRL exceedances is quite low, at 0.2 %. Table 3 shows the type of matrices and their countries of origin, which are quite diverse. The most conspicuous findings were those from Turkey, with 17 samples exceeding the maximum level (bell peppers, pomegranates, lentils, chili peppers, quinces, pickled wine leaves and lemons).
Food Matrix | Country of Origin |
Samples > MRL
|
---|---|---|
Pineapple | Costa Rica |
1
|
Apricot | France |
1
|
Basil | Cambodia |
1
|
Laos |
1
|
|
Thailand |
1
|
|
Unknown |
1
|
|
Pear | Spain |
1
|
Green bean | Italy |
1
|
Cambodia |
1
|
|
Spain |
1
|
|
Thailand |
1
|
|
Dill | Italy |
1
|
Peanut | China |
3
|
Unknown |
1
|
|
Bell pepper | Turkey |
2
|
Moringa powder | Unknown |
1
|
Oregano | Unknown |
1
|
Pomegranate | Turkey |
5
|
Cucumber, frozen | Vietnam |
1
|
Currant, frozen | Poland |
1
|
Potato | Germany |
2
|
Coriander | Thailand |
1
|
Unknown |
1
|
|
Leek | Italy |
1
|
Lentil | Turkey |
2
|
Mango | Africa |
1
|
Ivory Coast |
1
|
|
Nectarine | Spain |
1
|
Chili pepper | Turkey |
1
|
Peach | South Africa |
1
|
Quince | Turkey |
2
|
Pickled grape leaves | Egypt |
1
|
Bulgaria |
1
|
|
Greece |
1
|
|
Turkey |
4
|
|
Unknown |
1
|
|
Lemon | Spain |
1
|
Turkey |
1
|
|
TOTAL Results |
51
|
Citrus Fruits
The highest rate of positive samples is among citrus fruits. We’ve analyzed approximately the same number of citrus samples over the past 10 years, so we can make a good comparison (see also Table 4 and Diagram 1).
Assessments must consider that chlorpyrifos is not a systemic substance. That means it isn’t taken up into the plant’s interior from the soil via its vessel system. A majority of the residues are on the peel, which normally isn’t eaten [6].
Year |
No. of Samples
|
Positive Samples
|
Ave. Value mg/kg
|
Max mg/kg
|
Samples > Max. Level
|
---|---|---|---|---|---|
2010 |
129
|
84 (65.1 %)
|
0.055
|
0.62
|
-
|
2011 |
147
|
90 (61.2 %)
|
0.034
|
0.24
|
-
|
2012 |
135
|
93 (68.9 %)
|
0.060
|
0.30
|
-
|
2013 |
104
|
73 (70.2 %)
|
0.044
|
0.30
|
-
|
2014 |
96
|
68 (70.8 %)
|
0.046
|
0.23
|
-
|
2015 |
117
|
77 (65.8 %)
|
0.037
|
0.29
|
-
|
2016 |
106
|
58 (54.7 %)
|
0.033
|
0.30
|
-
|
2017 |
141
|
68 (48.2 %)
|
0.021
|
0.27
|
1
|
2018 |
109
|
31 (28.4 %)
|
0.026
|
0.22
|
1
|
2019 |
111
|
17 (15.3 %)
|
0.039
|
0.28
|
-
|
Diagram 1: Percent of positive samples in conventionally produced citrus fruits (CVUAS, 2010–2019)
Diagram 1 presents the percentage of samples with quantifiable chlorpyrifos residues (gray columns). The samples that exceeded the „new“ residue MRL of 0.01 mg/kg (blue columns) were also calculated. A noticeable reductive trend can be seen from 2016; the new toxicological assessments from EFSA were carried out in 2014.
The situation for citrus fruits from Spain is even more notable. It is quite evident here that the producers reacted quickly and that, in the meantime, chlorpyrifos has been practically eradicated.
Diagram 2: Spanish citrus fruits with chlorpyrifos residues, in % (CVUAS, 2010–2019)
Of course, the interesting question for the consumer is which insecticide will now take the place of chlorpyrifos in Spanish citrus production (see Table 5).
Year |
Insecticide Substances
|
Frequency of Detection in Spanish Citrus Fruits (%)
|
---|---|---|
2015 |
Chlorpyrifos
|
70.8
|
Pyriproxyfen
|
58.3
|
|
Chlorpyrifos-methyl
|
31.3
|
|
2016 |
Chlorpyrifos
|
58.8
|
Pyriproxyfen
|
54.9
|
|
Chlorpyrifos-methyl
|
17.6
|
|
2017 |
Pyriproxyfen
|
72.3
|
Chlorpyrifos
|
47.7
|
|
Chlorpyrifos-methyl
|
40.0
|
|
2018 |
Pyriproxyfen
|
64.5
|
Chlorpyrifos-methyl
|
37.1
|
|
Chlorpyrifos
|
29.0
|
|
2019 |
Pyriproxyfen
|
56.7
|
Chlorpyrifos-methyl
|
48.3
|
|
Spirotetramat, sum
|
30.0
|
As Table 5 shows, pyriproxyfen, chlorpyrifos-methyl and spirotetramat were frequently applied in 2019. EU authorization for chlorpyrifos-methyl was also not extended, however. This means that the Spanish citrus fruit producers will have to once again make adjustments.
Samples from organic production
We have analyzed about 4,000 samples of plant-based foods from organic production for residues of chlorpyrifos since 2010. Three percent of these contained this substance, albeit mostly in only trace amounts smaller than 0.01 mg/kg (see Table 6). Traces of substances can also occur in the end product as a result of drifting, cross-contamination during the harvest, packaging or marketing. Only 10 samples contained residues of 0.01 mg/kg or above (Table 7). All samples were in compliance with the valid MRLs.
Food Group | Sub-Group |
No. of Samples
|
Chlorpyrifos positives
|
Ave. Value mg/kg
|
Max mg/kg
|
Min mg/kg
|
---|---|---|---|---|---|---|
Alcohol-free drinks |
78
|
2 (2.6 %)
|
0.004
|
0.006
|
0.001
|
|
Baked goods |
15
|
-
|
|
|
|
|
Fats, Oils |
96
|
5 (5.2 %)
|
0.006
|
0.011
|
0.003
|
|
Vegetables | Leafy Veg. |
475
|
12 (2.5 %)
|
0.003
|
0.009
|
0.001
|
Fruiting Veg. |
556
|
2 (0.4 %)
|
0.003
|
0.003
|
0.002
|
|
Sprouting Veg. |
126
|
2 (1.6 %)
|
0.003
|
0.005
|
0.001
|
|
Root Veg. |
186
|
2 (1.1 %)
|
0.004
|
0.007
|
0.001
|
|
Vegetable products |
160
|
10 (6.3 %)
|
0.012
|
0.025
|
0.001
|
|
Cereals |
142
|
2 (1.4 %)
|
0.002
|
0.002
|
0.002
|
|
Cereal products |
100
|
2 (2 %)
|
0.006
|
0.009
|
0.002
|
|
Spices |
36
|
-
|
|
|
|
|
Legumes, Oil seeds, Nuts, Soy |
244
|
5 (2 %)
|
0.007
|
0.009
|
0.006
|
|
Potatoes & Starchy plant-parts |
79
|
-
|
|
|
|
|
Nutritional supplements |
7
|
2 (28.6 %)
|
0.010
|
0.011
|
0.009
|
|
Fruit | Berries |
223
|
2 (0.9 %)
|
0.001
|
0.001
|
0.001
|
Exotic Fruit |
189
|
9 (4.8 %)
|
0.004
|
0.01
|
0.001
|
|
Seed Fruit |
197
|
5 (2.5 %)
|
0.001
|
0.003
|
0.001
|
|
Stone Fruit |
93
|
8 (8.6 %)
|
0.003
|
0.008
|
0.001
|
|
Citrus Fruit |
252
|
24 (9.5 %)
|
0.003
|
0.008
|
0.001
|
|
Fruit products |
292
|
33 (11.3 %)
|
0.004
|
0.008
|
0.001
|
|
Mushrooms & Mushroom products |
86
|
-
|
|
|
|
|
Baby food |
128
|
-
|
|
|
|
|
Tea |
49
|
4 (8.2 %)
|
0.020
|
0.043
|
0.006
|
|
Pasta products |
21
|
-
|
|
|
|
|
Wine & Wine products |
151
|
-
|
|
|
|
|
Seasoning sauces |
11
|
2 (18.2 %)
|
0.003
|
0.003
|
0.003
|
|
Other |
42
|
-
|
|
|
|
|
TOTAL Results |
4034
|
133 (3.3 %)
|
0.005
|
0.043
|
0.001
|
Table 7 lists the samples from organic production that have contained chlorpyrifos in amounts of 0.01 mg/kg or above in the past 10 years, since 2010. These have mainly involved moringa, barley grass and camomile tea, products that undergo a drying process, which tends to concentrate the residues. This must be factored into the assessment, which resulted in all of these samples adhering to the legal guidelines.
Year | Sample Type | Country of Origin |
Quantity mg/kg
|
---|---|---|---|
2015 | Banana | Mexico |
0.01
|
2017 | Moringa | Thailand |
0.01
|
2016 | Moringa | Thailand |
0.01
|
2012 | Olive oil | Unknown |
0.011
|
2017 | Moringa | Unknown |
0.011
|
2019 | Moringa | Unknown |
0.011
|
2017 | Moringa | Unknown |
0.012
|
2017 | Moringa | Unknown |
0.021
|
2012 | Camomile tea | Egypt |
0.023
|
2016 | Barley grass | Bulgaria |
0.025
|
2016 | Moringa | India |
0.025
|
2018 | Camomile tea | Unknown |
0.043
|
Summary
Approximately 10 % of the conventionally produced samples analyzed over the past 10 years have contained chlorpyrifos residues, especially those coming from China, India, Vietnam and Turkey. Now the substance is no longer permitted for use in the EU and the maximum amounts will be set at the limit of quantification of 0.01 mg/kg.
Enormous efforts and the most stringent of requirements ensure that authorization is only given for pesticides that present no risk to our health. However, this is only possible within the realm of our current scientific knowledge. It is therefore meaningful and important that pesticides be regularly re-assessed. The list of substances that have lost this authorization over the years is long. Examples include old chloro-organic substances such as DDT and lindane; endocrine effective substances such as vinclozolin and procymidon; some phosphonice acid esters such as E605; and neonicotinoids such as clothianidin and pyrethroids, etc.
For consumers that are especially concerned about their health, organic produce provides an alternative. Although 3 % of our samples tested positive for chlorpyrifos, these were only in trace amounts, probably the result of drifting or cross-contamination.
Photo credit
CVUA Stuttgart, Andrea Karst, pesticide laboratory.
References
[1] Stuttgarter Zeitung: EU verbietet Insektenkiller Chlorpyrifos, retrieved on 13 Jan. 2020
[2] Zeit: EU-Kommission verbietet umstrittenes Insektizid, retrieved on 4 Feb. 2020
[3] Virginia Rauh et al, PNAS May 15, 2012 109 (20) 7871–7876
[4] Spiegel: Pestizid schädigt Gehirne Ungeborener, retrieved on 13 Jan. 2020
[5] European Food Safety Authority EFSA : Chlorpyrifos: Bewertung ergibt Auswirkungen auf die menschliche Gesundheit, retrieved on 13 Jan. 2020
[6] Food Safety Magazine: Distribution of Chlorpyrifos Residues in Citrus Fruits, retrieved on 17 Jan. 2020
Translated by: Catherine Leiblein