Nicotine in Food – What Does Smoking Have To Do With It?

Report from a day in the lab

Hanna Marks


CVUA Stuttgart consistently finds residues of the pesticidal substance nicotine in fruits and vegetables, despite being no longer authorized for use in the EU. In addition to the targeted use of nicotine as a pesticide or as an „ecological“ means of combating plant pests with tobacco brew (see, in German, Nicotine from Tobacco – a ‚Natural‘ Method Against Plant Pests?), quantities of nicotine found can also stem naturally from the plant itself, or be the result of contamination from tobacco dust or smokers‘ hands. Investigations carried out by CVUA Stuttgart show to what extent foods can be contaminated by nicotine.


Application or Contamination?

In accordance with Regulation (EC) No. 396/2005, the legally established maximum residue level (MRL) of the insecticide nicotine for unprocessed fruits and vegetables, with the exception of fresh herbs, is 0.01 mg/kg. Since 2017 CVUA Stuttgart has analyzed a total of 259 samples of unprocessed fruits and vegetables (excluding fresh herbs) for the presence of nicotine, resulting in 19 anomalies with findings above the legal MRL. Taking the analytical margin of error of 50% into account, six of the 19 samples were verified as exceeding the limit and were rejected.


Table 1: Nicotine Findings in Unprocessed Fruits and Vegetables (excluding fresh herbs*), CVUA Stuttgart
Origin of Samples Total No. of Samples
Quantities of Nicotine
≤ 0,01 mg/kg**
> 0,01 mg/kg and ≤ 0,02 mg/kg
> 0,02 mg/kg***
104 (91 %)
7 (6 %)
3 (3 %)
EU (excluding Germany)
70 (93 %)
3 (4 %)
2 (3 %)
Third Countries
52 (93 %)
3 (5 %)
1 (2 %)
14 (100 %)
240 (93 %)
13 (5 %)
6 (2 %)

* Herbs have a different MRL and are not included in this table.

** 0.01 mg/kg generally refers to the limit of determination and the MRL.

*** Exceedance of the MRL for nicotine is verified, in consideration of the analytical fluctuation margin of 50%.


We can make a legal judgment of the samples based on our analytical results, but the measured amounts don’t tell us how the insecticide ended up in the sample. Was there an application of a pesticide, was the sample contaminated, or did the plant naturally produce the substance itself?


Don’t forget to wash your hands

Nicotine is found naturally in tobacco plants and, in smaller amounts, in other solanaceae plants such as potatoes, tomatoes and eggplants. There is some discussion as to whether it also occurs in plants such as porcini mushrooms and tea, but no scientific evidence has been found thus far. Contamination from nearby tobacco fields or tobacco processing plants are more likely sources. The use of home-made tobacco brew was highlighted in our Internet report (in German) „Nicotine from Tobacco – a ‚Natural‘ Method Against Plant Pests?“. Even a single cigarette butt on the field, which tend to appear during the harvest, can lead to significant amounts in food [1]. So how does our food get contaminated in daily life?

Illustration 1: Lettuce – but please, without the cigarette!

Illustration 1: Lettuce – but please, without the cigarette!


Imagine a customer indulging in a cigarette just before his weekly shopping trip. Once in the shop he picks up a head of lettuce, turning it over in his hands to see if it’s the best one available. CVUA Stuttgart reconstructed this situation with lettuce, apples and peaches, testing the food item thereafter for any residues of nicotine. After having smoked a cigarette, the tester alternatively took a dry food item then a wet one into his hand. While smoking and before touching the peaches the smoker held the lit end of the cigarette close to his inner palms between puffs, so that the hands were in close contact with the nicotine.


Illustration 2: Nicotine amounts in lettuce, apples and peaches, before and after contact with a smoker’s hands.


Illustration 2: Nicotine amounts in lettuce, apples and peaches, before and after contact with a smoker’s hands.


The experiment shows that no or comparatively little nicotine was transferred onto the apple or peach when the food was dry. In contrast, significant amounts of nicotine were detected when the food was moist. Nicotine is a very polar pesticide and therefore easily dissolved in water. An MRL of 0.01 mg/kg is valid for these three foods. This level was exceeded in all three moist foods after coming in contact with the hands of a tester who had previously smoked. Intensive contact via touching and cutting of the moist lettuce and peaches yielded higher levels.


When a smoker touches lettuce, with its large, irregular surface, there is a larger area for the nicotine from his hands to come in contact with than, e.g. an apple, with its naturally smooth surface. It is therefore conceivable that the lettuce will be more highly contaminated with nicotine than the apple. The assumption that nicotine comes from contamination and not from an application of pesticide is reflected in our research results: 10 of the 19 MRL exceedances were found in leafy vegetables.


Even if the test conducted at CVUA Stuttgart was just a model experiment, it shows that relevant amounts of nicotine can certainly be transferred to food after smoking a cigarette. So the rule still holds: don’t forget to wash your hands before coming in contact with food. This is also recommendable as a general hygienic rule.


We at the lab always wear disposable gloves when dealing with our samples; this precludes any risk of contamination from nicotine.


Info Box

The Insecticide Nicotine

Nicotine is a neurotoxin and binds to the so-called acetylcholine receptors in the brain. These are specialized binding sites on the cells necessary for specific biochemical signaling processes. This substance causes, among others, an increase in the respiratory rate, blood pressure and heart rate, and also promotes a tendency toward blood clotting, which increases the risk of thrombosis [2, 3].

Due to its high toxicity, nicotine has been banned for use in the EU since 2010. The so-called acute reference dose (ARfD) is used to judge the possible toxic risk resulting from short-term exposure via residues in foods. The ARfD for nicotine is 0.0008 mg/kg bodyweight [3].

A nicotine amount of 0.021 mg/kg green lettuce, which is a verified exceedance of the MRL, exhausts the ARfD in accordance with the EFSA PRIMo-Model Revision 3 for small children at 99.9 %. If the ARfD is exhausted by 100 %, high rates of consumption of this food could lead to the impairment of one‘s health [4].


Expression of thanks goes to

Anja Barth, Sahra Söhnholz and Bärbel Illg


Photo credit

CVUA Stuttgart, pesticide laboratory



[1] Uptake of nicotine from discarded cigarette butts – A so far unconsidered path of contamination of plant-derived commodities, Selmar et al., Environmental Pollution 238, 2018

[2] Deutsches Krebsforschungszentrum: Wirkungsweise des Nikotins (viewed on 02 Jan. 2019)

[3] EFSA Statement: Potential risks for public health due to the presence of nicotine in wild mushrooms, The EFSA Journal RN 286, 1–47, 2009

[4] EFSA model for chronic and acute risk assessment, in the currently valid version

(As of January 2019: "PriMo Revision 3" as MS-Excel file)


Translated by: Catherine Leiblein


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Report published on 26.02.2019 14:00:45