Complex sentence: An additional concern is the health of the humans who participate in a colonization venture, including visual impairment or brain damage--for example, a 2016 study suggested that space colonizers may risk neural damage due to cosmic radiation.
Split into simpler sentences: An additional concern is the health of the humans who become a part of a colonization venture. For example, a 2016 study suggessted that space colonizers may risk neural damage due to cosmic radiation.