2,5 stars - between "OK" and "liked it" (regardless of the fact that the book was definitely too dark to be a good 'beach book', and was marketed as such). Imagine reading a Reader's Digest 'condensed' version of 
Gone with the Wind - 
The Island mas the makings of an epic, but is insufficiently developed. And no wonder: the author had a great vision and came up with an interesting story on an interesting topic, but the execution was less good than the project deserved. (Sample fragment to follow).
Against: 
- (Sometimes) wooden dialogue
- Spoon-fed expositions (argh)
- too many "and then!!!" moments, some of them almost laughably so.
- Maria, whom I strongly suspect? of being the protagonist, is too selfless to be true
- redundant narrative frame and narrative frame characters
- to freely shifting PoV for my taste
Pros:
- great subject matter
- convincing research
- this book taught me something, which is more than I expected from it.