# Why can't carbon and nitrogen be detected in ICP-MS and ICP-OES techniques?

Why can't carbon and nitrogen be detected in ICP-MS and ICP-OES techniques?

My book says this technique is efficient for detecting multiple elements, with exception of halogens and carbon. I found somewhere that ICP is an open system, therefore it doesn't allow carbon detection. But why is that exactly?

• Hi and welcome to chemistry.stackexchange.com. Feel free to take a tour of the site. Visit the help center to learn more about it. If you like the answers you receive, consider upvoting them and accepting the best one. – Jan Dec 3 '15 at 19:59

As you say, air is allowed to enter the plasma. Air consists primarily of $\ce{N2}$ and $\ce{O2}$, and would clearly interfere with any oxygen or nitrogen in the sample. The problem is not that ICP-MS or -OES cannot detect them, the problem is air.