Skull and crossbones for nitric acid
Handling with specific nitric acid-containing cleaning products can lead to serious health damage. Inhalation of nitric acid fumes/vapours and the nitrous gases released from nitric acid poses a serious health risk. This is shown by cases reported by physicians and by case reports of the German poison control centres to the Federal Institute for Risk Assessment (BfR). The BfR's assessment of the acute toxic effects of nitric acid has led to the following findings: the fumes, vapours and gases originating from nitric acid may have a toxic effect even after a single exposure or relative short-term inhalation. On the initiative of the BfR, the German Federal Authority for Chemicals has now proposed to the European Chemicals Agency (ECHA) to classify nitric acid in the highest hazard category for inhalation exposure, that it is labelled with the "skull and crossbones" symbol, and that it must bear a danger warning and the hazard statement "Fatal if inhaled". "These measures are necessary to effectively restrict the use of nitric acid in consumer products, since it poses serious health risks for consumers", says BfR President Professor Dr. Dr. Andreas Hensel.
The Federal Institute for Risk Assessment (BfR) lobbies for adjusting the classification and labelling of nitric acid for acute inhalation toxicity by the European Chemicals Agency (ECHA). So far, only the corrosive effects on the skin and eyes have been taken into account, but not the effects following inhalation. Nitric acid can be extremely dangerous even after short-term inhalation due to rapid and progressive acute pulmonary oedema. According to the European regulation on the classification, labelling and packaging of chemical substances and mixtures (CLP Regulation (EC) No. 1272/2008) nitric acid requires the labelling with signal word “Danger” and hazard statement “Fatal if inhaled” (H330) as well as the “skull and crossbones” as a symbol of danger for acutely toxic substances of Category 1.
The BfR opinion on specific nitric acid-containing cleaning products published in response to cases of poisoning following the use of the detergent ‘POR ÇÖZ’ which contained 25 % nitric acid (BfR opinion No. 041/2010, 6 September 2010) forms the basis of the BfR’s decision to lobby for an adjustment of classification and labelling of nitric acid at the European level. In this opinion, the BfR also assessed the detrimental health effects of nitric acid when inhaled. Results: even after short-term inhalation, nitric acid is equally toxic to humans and animals. If detergents containing nitric acid are used, life-threatening concentrations of nitric acid fumes/vapours and nitrous gases (e.g. NO2) can be formed in the indoor air, especially if nitric acid comes into contact with metals or organic materials. In the respiratory tract, inhalation of these gas / fume mixtures can cause irritation of the mucous membranes, bronchial catarrh, pneumonia and can, within a typical latency period of 3 to 30 hours, lead to an accumulation of fluid in the pulmonary alveoli (pulmonary oedema) and hence even death. The German poison control centres have so far reported roughly 30 cases to the BfR, in addition to cases reported by attending physicians, where in some cases severe damage was caused to the health of people as a result of inhaling fumes or vapours following household use of products containing nitric acid.
In accordance with the EU regulation on the classification, labelling and packaging of chemical substances and mixtures, the classification “acutely toxic” of Category 1 of nitric acid is a precondition for further consumer protection measures with regard to the labelling and packaging of products containing nitric acid. As soon as the recommendation to classify nitric acid as “acutely toxic” of Category 1 will be accepted and comes into force on the European level, stricter safety requirements for the packaging such as child-resistant fastenings and tactile warnings will apply to aqueous mixtures which contain 1 % nitric acid or more. In addition, restrictions will apply to the trade of consumer products containing nitric acid such as a self-service ban for consumers and a host of duties and requirements for those putting nitric acid into circulation. This comprises permit, reporting and recording duties or proof of relevant expertise. All these requirements will have to be met before the product is sold to resellers.
About the BfR
The Federal Institute for Risk Assessment (BfR) is a scientific institution within the portfolio of the Federal Ministry of Food, Agriculture and Consumer Protection (BMELV). It advises the Federal Government and Federal Laender on questions of food, chemical and product safety. The BfR conducts its own research on topics that are closely linked to its assessment tasks.