The phrase "are just one element" is correct and usable in written English.
You can use it when discussing components or parts of a larger whole, emphasizing that there are additional elements involved.
Example: "In the study of ecosystems, plants and animals are just one element of the complex interactions that occur."
Alternatives: "are merely one component" or "are simply one part".
In fact, the migrants are just one element in the chaos created by striking French port workers that will fade once Calais gets back to normal.
She also stresses that digital games are just one element of Angry Birds Playground, with board games, sports and physical activities taking a high priority alongside elements that even a traditionalist education secretary might appreciate.
Though there are riffs on gefilte fish, including versions made with salmon and even one using chicken, they are just one element in a book that reworks typical Jewish cooking with improvisational flair.
But when it comes to deciding what music to broadcast, online surveys are just one element in a complicated formula that also involves conventional testing, competitors' playlists, sales data, request line information and hunches.
To put it in other words, those problems that have not been settled with NATO are a cornerstone of Russia's foreign policy, while for the alliance they are just one element of its broader partnership policy.
An exceptional projects are just one element of city making and urban studies.
The composition of words on page or screen was just one element in that verbal system, but it was the one that caused writers most thrills and fret.
They have not yet received a final report on the tests, which were just one element of security research at the airport.
This is just one element of Apple's focus on the privacy of the data it is utilizing in New Maps.
"And also, very quickly they're much more secure, because they realize, 'I'm just one element in here; this isn't hanging on me.' And they tend to have more fun".
The blatant attacks on US elections – and political officials – is just one element as continued hacking and doxxing [releasing stolen documents] of US officials and agencies serves to embarrass the Obama administration.
