Pilot Monitoring Project on Infant Formulae gives the All Clear for Highly Toxic Pesticides

Ein Bericht aus unserem Laboralltag

Ann-Kathrin Wachtler, Nadine Ebert, Michelangelo Anastassiades

Babies are best breast-fed during their first six months of life according to the WHO, but in some situations it is necessary to rely on infant formulae as an alternative. Since babies and young children are the most sensitive of all consumer groups, they should not be exposed to toxic residues in their food. In order to investigate the residue situation in infant formula, therefore, we analyzed 80 samples of formula and 54 samples of milk in an EU-wide project. We can now give an all-clear signal for several toxicologically critical substances, but we must also report on findings of other residues.

Illustration 1: Milk powder is commonly used in the preparation of infant formulae as an alternative to breast milk. (Photo: Adobe Stock)

Background

For the assessment of pesticide residues in baby food a default maximum level of 0.01 mg/kg is applied to the ready-to-eat products within the EU. Some substances are so toxic, however, that even levels under this very low limit are considered to be unsafe. The European Food Safety Authority (EFSA) came to the conclusion in a position paper that, for pesticides with a health based guidance value (HBGV) of < 0.0026 mg/kg body weight per day, this maximum level of 0.01 mg/kg is not sufficiently safe for infants younger than 16 weeks [1]. Lower maximum residue levels were thus calculated for these especially toxic pesticides, in order to ensure a sufficient level of safety. In 2018 the European Commission proposed a small-scale pilot monitoring project to determine whether residues of these critical substances were detectable and, if so, whether they should be more strictly monitored.

In 2020, therefore, the EU Reference Laboratory for single residue methods for pesticides, situated at CVUA Stuttgart, investigated a total of 80 samples of infant formulae and 54 samples of milk for the presence of 13 particularly toxic substances. First, analytical methods were optimized and validated, in order to ensure that the residues of these substances, even at sufficiently low amounts, could be detected and quantified. Measuring the trace residues at necessarily low concentration levels is especially challenging. Working together with the EU Reference Laboratory for pesticide residues in foods of animal origins situated at CVUA Freiburg, samples from all over Europe were collected and analyzed. These were not the samples used by the official food monitoring program; they were collected especially for the monitoring project of the EU Reference Laboratory. Since the procurement of the samples required so much effort, we decided to use the opportunity to investigate other substances as well. Although these other compounds are not classified as toxicologically critical, they are ubiquitous and were thus expected to be present in milk and infant formulae. Our findings are reported here.

The palette of samples

The analyses focused on infant formulae for babies up to the age of 16 weeks (often labeled with “Pre“ or “1“). Such products are mainly composed of milk powder, plant-based fat, emulsifiers, vitamins and mineral nutrients. There are six distinctive categories:

a) Conventional (normal) infant formula
b) Lactose-free infant formula (for infants with lactose intolerance)
c) Hypo-allergenic infant formula (for infants with milk protein intolerance)
d) Anti-Reflux infant formula (contains thickening agents to prevent spitting-up)
e) ”Comfort“ infant formula (for infants with specific digestive disorders, e.g. colic)
f) Plant-based infant formula (e.g. soy or rice)

Illustration 2: A colorful mixture of Europe-wide infant formulae on our lab counter. (Photo: CVUA Stuttgart)

In most cases, the products sampled were powders that are to be prepared by mixing with water. Since most infant formulae are milk-based, 54 samples of cow’s milk as the main raw material used in the production of infant formulae, were also analyzed.

What was analyzed?

Our investigations focused on 13 substances that are classified as toxicologically critical. Each of these had to be analyzed using complex methods for single residues. In addition, we looked for another six substances that, in our experience, could be expected in such products. The analyzed samples came from all over Europe (see above), in order to get the broadest possible impression of the situation on the European market. Approximately one-third of the analyzed infant formula samples were produced in Germany. Most of the infant formula products sold in supermarkets are of the “normal” type (Category A), and such products therefore made up the lion’s share in this monitoring project. Our CVUA partner lab in Freiburg analyzed the same samples for an additional 47 substances classified as especially toxic using multi-residue methods, the results of which are reported in an article (in German), “European Reference Laboratory Special Topic: Monitoring of Pesticide Residues in Milk and Infant Formula Throughout Europe” [2].

Analytical Results

Our analyses of the especially toxic substances revealed only trace amounts of nicotine. The detected residue amounts were all under the maximum levels determined to be safe, however. There are various ways that nicotine traces can find their way into baby foods. Besides its use as an insecticide, contamination from nicotine can also result from tobacco dust or smoke. We have reported on the different pathways of nicotine into food in our report “Nicotine in Food – What Does Smoking Have To Do With It?” [3]. In the analyzed infant formulae we found no residue levels above the envisaged maximum level.

* Refers to the ready-to-eat product (after mixing with water)

As expected, we also found residues of other substances that we included in our scope of analysis. In fact, all of the samples contained traces of one or more of these substances. In 13 of the infant formula samples there were even amounts exceeding the legal maximum level, 11 of which concerning chlorate and two concerning phosphonic acid. None of these 13 samples were manufactured or sold in Germany.

The analysis of milk samples also revealed residues of chlorate (9 samples), at levels exceeding the legal limit, even after taking into account the measurement uncertainty of 50 %. A new valid maximum level of 0.1 mg/kg for cow milk has been in effect since mid-2020 [6], however, which, if applied in our study, would not have been exceeded by any samples except one. Residues from chlorate can also stem from various sources. In addition to its application as an herbicide, chlorate can also form as a byproduct from drinking water disinfection, ending up in food after having been used in the cleaning of processing facilities and food containers. Further information on chlorate and phosphonic acid can be found in our report „Residues and Contaminants in Fresh Vegetables from Conventional Culture, 2019“ and in the Info Box [7].

* taking into account the measurement uncertainty of 50 %

Our Conclusion

In the 80 samples of infant formula and 54 samples of milk that we analyzed for the presence of 13 toxicologically critical substances, we were only able to detect one such substance: nicotine. This was only found in trace amounts, however, at levels not classified as harmful. On the other hand, we were also able to detect residues from other substances which, while less toxic, do occur frequently. These included chlorate and phosphonic acid, found in quantities even above the legal maximum level. These particular samples had neither been produced nor sold in Germany.

This monitoring project shows overall that, in concert with the findings of our colleagues in Freiburg, there are no serious toxicological risks for infants up to the age of 16 weeks. Nevertheless, infant formula is not completely free of residues.

Further information regarding our research results and methods are available to interested parties and other professionals on our website [11].

Quellen

[1] Scientific opinion on pesticides in foods for infants and young children

[2] Aus der Arbeit des Europäischen Referenzlabors: Monitoring von Pestizidrückständen in Milch und Säuglingsanfangsnahrung aus ganz Europa

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

[4] Deutsches Krebsforschungszentrum: Wirkungsweise des Nikotins (abgerufen am 25.01.2022)

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

[6] VO (EU) 2020/749

[7] Residues and Contaminants in Fresh Vegetables from Conventional Culture, 2019

[8] Entscheidung der Kommission vom 10. November 2008 über die Nichtaufnahme von Chlorat in Anhang I der RL 91/414/EWG des Rates und die Aufhebung der Zulassungen für Pflanzenschutzmittel mit diesem Stoff (ABl. L 307/7 vom 18.11.2008)

[9] BfR, Vorschläge des BfR zur gesundheitlichen Bewertung von Chloratrückständen in Lebensmitteln vom 12.05.2014

[10] BNN-Factsheet – Phosphonsäure Kaliumphosphonat (Kaliumsalz der Phosphonsäure), Fosetyl-Aluminium; Zusammenfassung des Kenntnisstands, September 2020

[11] Compilation of Analytical Observations Reports

Acknowledgement

This study was conducted within the framework of the Annual Work Program of the EURL-SRM, which is financed by the European Commission (DG-SANTE) and was co-financed by the CVUA Stuttgart.

We would like to thank all colleagues from National Reference Laboratories that have contributed to the project by providing infant formulae from their countries, the colleagues of the EURL-AO (based at CVUA Freiburg) for the collaboration, and the staff of the routine pesticide residues laboratory of CVUA Stuttgart for contributing in logistics and analysis.

Translated by Catherine Leiblein

Artikel erstmals erschienen am 06.05.2022 10:51:12