GHI webinar: Potential toxic compounds in foods - oxidation products in plant oils and inorganic arsenic in rice

Date: 29 April 2024, Time: 12 noon CEST

Duration: 1:30 hours

As by definition in any law around the world food has to be safe. However, we know from experience that a certain hazard is always associated with food production, storage, manufacturing and cooking. A series of hazards have been identified in the past and we know that there is an urgent need to control these hazards and minimize the health risk. In this webinar two topics will be addressed. This is the inorganic carcinogenic arsenic which is worldwide a substance of concern. The analysis of arsenic, especially the topic of speciation, will be discussed since not all arsenic containing compounds are toxicologically relevant. The second topic is on oxidation of lipids. It is known that exposure to oxidised lipids can increase the risk of colon cancer. Recently, an effect on non-alcoholic liver inflammation was also identified. This webinar will discuss the formation of the oxidised compounds – peroxides, endoperoxides etc. However, it is still not yet known which compounds are mainly responsible for these health effects.

This GHI webinar is brought to you by the GHI Chemical Food Safety Working Group and will be chaired by Dr. Diana Bogueva, Acting President of GHI. The overall mission of the GHI Chemical Food Safety Working Group is to investigate and formulate chemical safety issues in the broadest sense.

Oil oxidation - formation of potentially hazardous compounds

Dr. Michael Murkovic Professor at Graz University of Technology, Austria and Co-Chair of the GHI Chemical Food Safety Working Group


Oxidation of plant oils occurs during raffination, storage and cooking. Isomerisation reactions occur at high temperatures during raffination and also frying or roasting. Oxidation is present at practically any time during the life cycle of the unsaturated fatty acids. As long as oxygen is present the reaction continues which can run until complete polymerisation (hardening). A series of different peroxides, alcohols occur and the volatile compounds - which indicates the oxidation process for the consumer who experiences the typically rancid aroma - are formed at a later stage.
It is not yet clear which compounds or which compound class is responsible for the associated health risk, being colon cancer and/or non-alcoholic liver inflammation.
Liquid chromatography with mass selective detection is especially helpful for the analysis of these non-volatile oxidation products. The lipids are practically not absorbing in the UV range and the additional information which can be obtained by MS allows a clear identification of the oxidation products, even when they are not very stable as the peroxides. Profiling the oxidation products will help to estimate the health risk of the oxidised lipids.

A long rocky road to get inorganic arsenic in rice into legislation. What next?

Dr. Jörg Feldmann Professor at University of Graz, Austria


The lecture will feature why rice has an arsenic problem with an emphasis on factors which influence the accumulation of inorganic arsenic in rice. This is followed by the description of state-of-the-art analytical methodologies and novel developments in detecting the inorganic and carcinogenic forms of arsenic with low cost field deployable methods. Other arsenic rich foods such as seaweed will also be discussed. The last part will look ahead at other arsenic-containing compounds appearing in seafood. Reasons will be given why these arsenolipids should be tackled by regulators in the future. Here the complex analytical procedures and some toxicological aspects will be discussed.

Speaker 1:
Dr. Michael Murkovic

Dr. Michael Murkovic is a trained biotechnologist who was working for some time in the pharmaceutical industry developing fermentation processes for antibiotic and other bioactive substances. In 1993 he started his career at Graz University of Technology in the field of food chemistry with the main interest in the formation of carcinogenic compounds which are formed during processing and cooking. The focus is on the reduction of the formation by e.g. the use of antioxidants. In 2001 he became associate Professor in the field of food chemistry.
In food chemistry he has published more than 100 manuscripts in reviewed journals. Besides his scientific work he is teaching in the master program Biotechnology training in food chemistry, food biotechnology and quality assurance. Dr. Murkovic is Co-Chair of the GHI Chemical Food Safety Working Group and is also Chair of the GHI Supervisory Council.

Speaker 2:
Dr. Jörg Feldmann

Dr. Jörg Feldmann is an environmental analytical chemist who did his Master in Geochemistry (South Africa) and a PhD in Environmental Analytical Chemistry (Germany). He spent 2 years at the University of British Colombia (Canada) as Alexander von Humboldt Fellow before spending 23 years at the University of Aberdeen (Scotland, UK) and then moving to Austria in 2020. He has given around 200 invited presentations and published more than 300 peer-review papers (h-index 75) and received numerous prices and medals (e.g., RSC Interdisciplinary, European Award of Plasmaspectrometry) and has been elected to become a Fellow of the Royal Society of Edinburgh. Under his guidance more than 50 PhD students have graduated. He develops novel analytical methods based on elemental and molecular mass spectrometry for toxic and essential elements such as arsenic, selenium, mercury and fluorine (PFAS) in environmental and biological samples with an emphasis on food.

Chair & Event Moderator:
Dr. Diana Bogueva - President of GHI

Dr. Diana Bogueva, is the newly elected President of GHI. Her background is as a social scientist and journalist with interests in sustainable food consumption, alternative proteins, consumer perception of novel food processing technologies and generational consumer behaviour, food sustainability and harmonization. Diana’s work has won three awards: the Australian National Best Book winner in 2019 and the World’s Best Book award 2020 in the Vegetarian book category at the prestigious 24th and 25th Gourmand Awards, considered equivalent to the Oscars in the area of food books, for her co-edited book ‘Environmental, Health and Business Opportunities in the New Meat Alternatives Market’. She also won the 2020 Faculty of Humanities Journal Article of the Year Award at Curtin University for their co-authored paper “Planetary Health and reduction in meat consumption”, which was at the top 5% of all world research outputs scored by Altmetrics. Diana is also a finalist in the 10th International Book Award at America’s Book Fair 2019 for her co-edited book ‘Handbook of Research on Social marketing and its influence on animal origin food product consumption’. In 2022 Diana published her first co-authored book ‘Food in a Planetary Emergency’ with Professor Dora Marinova. This book is a timely overview of current food systems and the required transformations to respond to climate change, population pressures, biodiversity loss and use of natural resources. And, in May 2023, as a tribute to the authors' efforts, talented writing skills and passion, ‘Food in a Planetary Emergency’ was awarded the 'Best of the Best - The Future of Food Gourmand Award’ at the 28th Award Ceremony. In 2024, Diana's co-authored book 'Nutrition Science, Marketing Nutrition, Health Claims and Public Policy' published by Elsevier, was a finalist for the Association of America publisher's award for the professional and scholarly publishing PROSE award.

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