The debate over whether or not Bjørn Lomborg's book The Skeptical Environmentalist is science or not has been confused for a number of reasons.
First of all , if it is science it is interdisciplinary, and there are different ideas in different fields about what constiututes science. Actually calling it interdisciplinary is wrong. It is a politically charged debate of a social science problem of allocation drawing it's subject matter and notions of cost and utility from the natural sciences.
So it is not really 'inter'-disciplinary in the sense that there are two-way connections between the three subject layers (or there shouldn't be - Lomborg would maybe claim there is, this being part of his criticism of the environmental sciences). There are three distinct layers to the book and each of these - were the book a little better - would be distinguishable and debatable separately.

It is disconcerting that neither the author nor his defenders or his critics carry out this straight forward separation of concerns, since it renders the debate essentially meaningless.
The high profile of the debate is due entirely to the politics of the book, and not the social science or natural science material. The proponents of the book are almost exclusively proponenents of the political or social science discussions, whereas the criticism from the natural sciences has been quite unanimous (of course there is argument about the findings the book draws it's numbers from - that is what open scientific debate is about - but the majority vote as well as most of the arguments presented are against the books findings).
So the debate on whether or not the book constitutes science is an unhappy debate. While there clearly should be no censorship of the political material or even the allocation debates (rendering the verdict on the books scientific standing meaningless) Lomborg should know better than to pass an enormous accumulation of numbers from an uncontrollable number of sources with a complete lack of consistence as a consequence as well as some important factual and methodical errors in the treatment of the natural science parts of the material. The methodical failures are the most damning. Lomborgs book and to a large extent his rebuttals of criticism completely fail to accept that there are methodical barriers to what statements you can sensibly make about the numbers he quote so very many of. Lomborgs reads the material like the devil reads the bible.

So the conclusion remains that Lomborg should take care not to pass off the natural science parts of his book as anything remotely resembling science, and the comittee on scientific conduct should then simply have chosen not to comment on the book.
How nice that would have been. An open debate on the politics of choice and allocation, without accusations of inquisition from one camp and criminal stupidity on the other. If only Bjørn Lomborg had had the character and the conscience to say what Daniel Dennett does in the preface of his admirable book on evolution:

This book is largely about science but is not itself a work of science. Science is not done by quoting authorities, however eloquent and eminent, and then evaluating their arguments. Scientists do, however, quite properly persist in holding forth, in popular and not-so-popular books and essays, putting forward their interpretations of the work in the lab and the field, and trying to influence their fellow scientists. When I quote them, rhetoric and all, I am doing what they are doing: engaging in persuasion.

In fact Lomborg is doubly guilty of not holding to Dennett's view of science. Not only does he not take proper care to distinguish between what he has primary knowledge of himself and what he has only secondary knowledge of. His material itself is not the original science in most cases, but rather numbers drawn from the persuasion - not the science - of others. Much of the material he uses is secondary (UN and other organisations reports prepared for decisionmakers (i.e. lay readers) not scientists) or tertiary (newspaper commentary on such reports).