Frequently asked questions on arsenic in rice and rice products

The extent to which arsenic is hazardous to health depends on the compound in question and the oxidation level. A variety of different organic arsenic compounds can be detected in food. Some of the organic arsenic compounds that occur primarily in fish and seafood are not considered to pose any health risk. There has been little toxicological characterisation of other organic arsenic compounds detected in food so far. Inorganic arsenic compounds in particular are considered to be toxicologically relevant. The intake of a high dose of soluble inorganic arsenic compounds can lead to acute adverse health effects.

Chronic intake of smaller amounts of inorganic arsenic compounds over a long period of time can lead to skin changes and vascular and nerve damage, increase the risk for cardiovascular diseases and cause developmental toxicity.

Inorganic arsenic compounds are classified as carcinogenic to humans by international bodies. From the existing studies, an intake level that is not associated with an increased risk of cancer cannot be derived. Therefore, the presence of inorganic arsenic in food is undesirable in any quantity, but cannot be completely avoided.

Just like other cereals, the rice plant absorbs arsenic compounds through the roots. From here, the substance enters the fruit, i.e. the grains of rice, via the metabolism of the plant. It is known that rice can contain more arsenic in inorganic form than other plant-based foods.

Rice is often cultivated in the soil under anaerobic conditions (in the absence of oxygen) by flooding the fields, which leads to an increased availabilityof arsenic in the soil. If the irrigation water also contains high concentrations of arsenic compounds, this is reflected by higher concentrations in the grains of rice. As a consequence, the concentration of arsenic compounds contained in rice varies depending on the arsenic content of the soil and water in the regions in which it is cultivated, and also depending on the cultivation method and the type of rice. Because inorganic arsenic tends to accumulate in the outer layers of the grain of rice in particular, the concentrations in the finished product also depend on how the rice was processed.

Analyses by German federal states' ("Laender") monitoring authorities show that rice and rice products contain high concentrations of inorganic arsenic in comparison with other cereals. The average concentrations in white (milled) rice are 0.1 mgshort formilligram of inorganic arsenic per kgshort forkilogram of rice, high concentrations are 0.2 mgshort formilligram per kgshort forkilogram of rice (95th percentileClose dialogpercentilePercentileTo glossary). Brown rice, or "natural rice", contains higher concentrations than white rice, from which the outer layers have mostly been removed. Higher concentrations than those in white rice were also measured in rice cakes and rice flakes.

Various influences can contribute to the differences in the concentrations of inorganic arsenic between rice products and rice, such as the reduction of the moisture content during the production process of rice products, the origin of the rice (concentrations of arsenic in the soil and irrigation water), cultivation conditions, the degree of milling and the proportion of outer layers in the product, as well as the rice variety.

At the concentrations measured in rice and rice products, acute health impairments are unlikely for all population groups in Germany (infants, toddlers, children, adults and older people, including those who consume high or extremely high amounts). Even the (non-carcinogenic) effects known in connection with the long-term intake of inorganic arsenic, such as skin damage, vascular damage and damage to the nervous system in adults and in children, are unlikely when inorganic arsenic is ingested through consumption of rice and rice products at the concentrations measured.

No safe intake level can be defined in terms of the carcinogenic (cancer causing) effect of inorganic arsenic. For this reason, it is possible that the intake of inorganic arsenic through the consumption of rice and rice products may cause health risks with respect to a potential increase in the risk of cancer.

From epidemiological studies from South America and Asia, we know that, statistically, people who live in regions in which the drinking water contains high concentrations of arsenic and who therefore take in high amounts of inorganic arsenic compounds via drinking water on a daily basis have a higher risk of certain types of cancer.

In its risk assessment, the BfRshort forGerman Federal Institute for Risk Assessment made a comparison between the exposureClose dialogexposureExposureTo glossary of the different consumer groups in Germany (infants, toddlers, children, adults) to arsenic compounds in rice and rice products and the lowest exposure for which an effect was detected in these epidemiological studies. The results show that the consumption of rice and rice products can result in intake levels of inorganic arsenic that lie within the range of intake levels for which the epidemiological studies showed an association with an increased risk of lung cancer with the intake of inorganic arsenic in drinking water. For this reason, the BfRshort forGerman Federal Institute for Risk Assessment recommends measures for reducing the concentrations of inorganic arsenic compounds, particularly in products that are consumed mainly by infants, toddlers and children.

The European Union has decided on maximum concentrations for inorganic arsenic in rice and rice products for the following food categories: milled rice, non-parboiled (polished and white rice); parboiled rice and husked rice; rice cakes, rice waffles, rice crackers and rice cakes; rice for the production of food for infants and toddlers. Maximum concentrations were introduced by the European Commission on 1 January 2016.

The BfRshort forGerman Federal Institute for Risk Assessment sees further need for research to clarify in particular why rice products, such as rice waffles or rice flakes and creamed rice, may contain significantly higher concentrations of arsenic compounds than white rice in some cases. For this reason, manufacturers are called upon to take measures to reduce the concentration of arsenic compounds in their products as far as possible.

On behalf of the BfRshort forGerman Federal Institute for Risk Assessment, concentrations of inorganic and total arsenic in rice cakes and rice-based baby and infant food were examined by federal and state bodies as part of the 2014 food monitoring in order to improve the base of available data for a health risk assessment of these products. The results show that the concentrations of inorganic arsenic in the products analysed within the scope of these examinations were lower than in those rice products analysed in the tests, the results of which were used by the BfRshort forGerman Federal Institute for Risk Assessment as the basis for its opinion (018/2015).

The World Health Organisation’s (WHO) Codex Alimentarius Commission has published a code of practice for the prevention and reduction of arsenic contamination in rice, which is intended to serve as a guideline for the cultivation of rice and the manufacture of rice products.

Parents are advised not to feed their babies or toddlers exclusively with rice-based drinks or food, such as creamed rice. Where snacks are concerned too, they should vary between products, such as rice waffles and rice-free snacks.

With respect to feeding infants with rice-based drinks ("rice milk"), the BfRshort forGerman Federal Institute for Risk Assessment also refers to the recommendations of national and international bodies, which advise against this form of nutrition not only because of the high concentrations of arsenic in the products, but in particular due to the unsuitable composition of nutrients, which does not meet infants' needs.

Consumers cannot tell how much inorganic arsenic is contained in the rice or rice products. The BfRshort forGerman Federal Institute for Risk Assessment recommends consuming products, such as rice cakes or rice flakes/creamed rice, in moderation and varying these products with products based on other cereals, such as maize or wheat.

Some arsenic compounds can be passed from rice to water when rice is washed and cooked in plenty of water with a low arsenic concentration. Therefore, to reduce the concentration of inorganic arsenic in foods prepared at home, consumers can choose a preparation method that involves washing and cooking the rice in plenty of water and pouring off the excess water after cooking.

Consumers who suffer from coeliac disease (gluten intolerance) should observe the same recommendations as the general population for a healthy diet in relation to varying foods. An unbalanced diet focusing solely on rice and rice products should be avoided where possible. Instead, other gluten-free cereals, such as maize, millet, buckwheat, amaranth or quinoa should be added to the diet.

This text version is a translation of the original German text which is the only legally binding version.