Cadmium is a toxic heavy metal with a biological half-life of 10-30 years, which is widely distributed in the environment due to rock erosion and volcanism as well as emissions from industry. Cadmium enters foodstuffs from the environment via various uptake pathways. Cigarette consumption also leads to additional intake for smokers and passive smokers due to the cadmium content in tobacco leaves. Cadmium accumulates primarily in the kidneys, which can be damaged by long-term dietary intake. Damage to bone tissue is also possible.

Cadmium is a toxic heavy metal and occurs naturally in the earth's crust. It comes from weathering rocks or volcanic eruptions. Furthermore, cadmium is released into the atmosphere and from there into the soil through industrial emissions such as metal mining and smelting, industrial and agricultural waste, coal combustion, and use in batteries and alloys. It is introduced directly into the soil with phosphate fertilizers and sewage sludge.

In the environment, cadmium rarely occurs as pure metal, but mostly as inorganic compounds such as cadmium chloride, bromide, sulfate, oxide and sulfite.

In mammals, birds and fish, as well as plants, cadmium is present bound to proteins. Crop plants can take up cadmium from the soil to varying degrees, mainly through the roots. Various factors such as soil condition, crop type and different agricultural practices such as the use of phosphate fertilizers or sewage sludge influence uptake.

Cadmium accumulates in human organs, especially in the liver and kidney, and also in bones. It is excreted again only very slowly via the kidneys and intestines.

Acute poisoning through the consumption of water and beverages containing very high levels of cadmium causes gastrointestinal complaints and headaches only a few minutes after ingestion. The most sensitive organ of a long-term dietary cadmium intake is the kidney. However, chronic cadmium poisoning can also lead to hypertension, liver damage, and osteoporosis.

Cadmium can affect the metabolism and function of vital elements such as iron, calcium or zinc. An adequate supply of these elements is therefore essential. A deficiency can promote the absorption of cadmium. Since women, for example, are more frequently affected by iron deficiency and have a lower iron status, especially during pregnancy, they may be more highly contaminated with cadmium than men.

Commission Regulation (EU) No. 2023/915 sets maximum levels for cadmium for the following food groups: Vegetables, fruit, mushrooms, cereals, pulses, offal, fish and seafood, food supplements, infant formulae and follow-on formulae, processed cereal-based foods and baby foods for infants and young children, and chocolate and cocoa products.

Data on the occurrence of cadmium following the implementation of risk minimisation measures in recent years has shown that it is possible to reduce the cadmium content in many foods.

In addition to the European maximum levels, Austria has national action values for certain contaminants in foodstuffs for which there is no European regulation.

We analyse numerous foods from different product groups for cadmium every year. In the years 2010-2017, a total of 5,759 food samples and 2,088 drinking water samples were analysed for cadmium. Cadmium was detected in 87-100% of all analysed samples of cereals, vegetables, potatoes, pulses, oilseeds, chocolate and cocoa and cocoa products. The highest average cadmium levels of 1800 µg/kg were determined in algae, followed by significantly lower levels in cocoa and cocoa products (179 µg/kg), seafood (136 µg/kg), mushrooms (128 µg/kg), oilseeds (110 µg/kg), chocolate (87 µg/kg), offal (41 µg/kg) and cereals (30 µg/kg). In fruit, juices and meat, cadmium was only measured in 10-21% of the samples analysed. However, these levels were very low.

• Consume foods with higher cadmium content (e.g. wild mushrooms, seafood) less frequently or in smaller quantities
• Minimize the consumption of algae or the intake of food supplements based on algae
• Give preference to a varied mixed diet, avoid one-sided diets with biased food choices
• Pregnant and breastfeeding women should ensure a good mineral supply of iron, zinc and calcium in order to reduce cadmium intake.

The main intake of cadmium in non-smokers is due to food and amounts to about 90 %. The remaining exposure (10%) is composed of ambient air and drinking water (EFSA, 2012). Oilseeds, cocoa beans, wild mushrooms, nuts, cereals, seaweeds, and some vegetables are among the plant foods with the highest levels of cadmium exposure. Offal and seafood can also be contaminated with elevated levels of cadmium. However, it is often not the foods with the highest cadmium levels that make the greatest contribution to cadmium intake, but foods that are consumed in large quantities and frequently, such as cereals and vegetables (EFSA, 2009).

In addition to food, smoking is an additional source of exposure to cadmium. Young children may also ingest cadmium orally through house dust or soil (EFSA, 2009).

Risk assessment 2013

A total of more than 4,000 samples from 67 different food categories were tested for cadmium between 2007 and 2012. Foods particularly highly contaminated with cadmium are aquatic mollusks, mushrooms, cocoa products, chocolate and certain food supplements. In the case of cereals and vegetables, cadmium content is not only site-dependent, but also depends on species, variety and plant organ. In chocolate, cadmium content correlates with cocoa content.

Cadmium is mainly absorbed via highly consumed foods. The cadmium intake via the foods examined in Austria in 2007 - 2012 amounts to a total of 24%, 30% and 33% of the weekly tolerable intake (TWI value) for men, women and children, respectively. High consumers of potatoes and cereals among men and women exhaust the TWI value via the examined foods to 57 % and 71 %. High consumers of potatoes and chocolate reach 64 % of the TWI value. Important sources of cadmium intake for the Austrian population are cereals, potatoes, chocolate and leafy vegetables.

This risk assessment deals exclusively with oral cadmium intake from food, but it should be noted that cigarette smoke is a very high contributor to cadmium exposure.