With one massive, global health concern on everyone’s mind these days, it’s easy to forget that other problems haven’t gone away and may even be just as important or becoming even more critical. They’re just not getting the media attention currently.
Nitrosamines are one such threat that was previously in the news. They are organic compounds featuring a nitroso group and amino group. They have the generic formula R2N-N=O where the R groups are typically alkyl in nature. They can occur naturally in some food and drinks including cured meats, some cheeses, beer(!), dried milk and fish. They are also commonly present in cosmetics and one of the difficulties is that they often form over time from the reaction of nitrite preservatives with amines. Nitrosamines are not directly carcinogenic per se but metabolomic activation can make them so.
As well as being in personal care products and food and drink, the European Medicines Agency (EMA) and US Food and Drugs Administration (FDA) reported the presence of low levels of a particular nitrosamine impurity called N-nitrosodimethylamine (NDMA) in ranitidine drugs which are available both by prescription and over the counter as a treatment for heartburn, indigestion and acid reflux. The worry was not so much in the presence of NDMA but the observation that contamination levels may increase in concentration during storage. The FDA has subsequently requested that manufacturers remove all ranitidine drugs (e.g. Zantac®) from sale.
So, should I care? Well, the presence of potential carcinogens in food and beer(!) is worrisome enough and the additional presence of a substance linked to gastric cancers is found in medicines being sold to treat gastric conditions is an unpleasant irony.
As NDMA can be formed by increased temperatures, in this case, GC-MS is not an option for analysis. There are other solutions, however, to detect nitrosamines. The FDA has published two methods for detecting NDMA in ranititidine products, one by LC-MS/MS on a triple quadrupole mass spectrometry and one by high-resolution accurate mass (HRAM) LC-MS mass spectrometry using the Thermo Scientific™ Q Exactive™ LC-MS/MS system. More details of this aspect have been discussed previously on this site.
In this day and age, health scares are more and more prevalent. The World Health Organization lists cancer as the second leading cause of death globally, with a wide range of causes from tobacco, alcohol, sunlight, air pollution, obesity, plutonium… (. Some of these are easier to avoid than others, but the thought that cancer-causing chemicals are being formed in our foods, drinks and cosmetics is something we should be concerned about. Fortunately, LC-MS provides an excellent way to check for them.