Nataf R, Skorupka C, Amet L, Lam A, Springbett A, Lathe R, Porphyrinuria in childhood autistic disorder: implications for environmental toxicity. Toxicol Appl Pharmacol. 2006 Jul 15;214(2):99-108. Epub 2006 Jun 16.
The 2006 Nataf paper caused quite a stir in the "autism is mercury poisoning" wing of the autism community. The paper's essential findings were that urinary porphyrns can give an accurate estimate of the amount of mercury in the person's body; the levels were elevated in autistic individuals but not those with Asperger's; and that levels were "normalized" with an oral chelation product.
A February 2007 review of the mercury in vaccines and autism theory found relative to Nataf:
Unfortunately the study done by Nataf et al. reported urinary porphyrin levels as a ratio to creatinine. Not only does this make actual quantification ambiguous, it exposes the results to known inconsistencies of creatinine measurements taken from autistic children based on spot urine collections. Furthermore, Nataf et al. apparently did not actually measure mercury. Potential weaknesses taken altogether, this study doesn’t seem to provide scientific proof of [nothing].
Kev Leitch of LeftBrain/RightBrain had an email conversation with Professor Lathe (apparently the senior author) on some of the peculiarities in the paper: the role of Lorene Amet and the significance of the findings (August, 2006: Part I and Part II). In short,
the shortcomings in the Porph study and Professor Lathe’s reliance on extremely haphazard science. I also touched on his strange reluctance to publish all associated data relating to that study and his peculiar relationship with co-author and DAN! doctor Lorene Amet. I also reported on how Lathe conceded that several key aspects of his theory relied on unverified science – notably the Holmes et al paper.
In an April, 2007 post, Kev Leitch again enumerates the weaknesses and flaws of the Nataf paper.
In summary, Nataf et al. was based on very questionable science. This paper cannot be said to "demonstrate that vaccines can cause autism."
Apparently the Vaccine Injury Compensation Program agreed. The Autism Omnibus Ruling of March 12, 2010, dismissed the mercury causation theory. Nataf's work was mentioned in the King vs HHS case.
I find that Dr. Brent’s testimony concerning these issues was persuasive, and that the testimony of Dr. Aposhian was not. I conclude that the Holmes, Hu, Adams, and Bradstreet studies are of doubtful reliability, and that the contrary studies cited by Dr. Brent provide better evidence. I conclude that the Woods and Nataf articles also provide no significant support to Dr. Aposhian’s theory. Accordingly, after analysis of all of the evidence in this regard, I conclude that there is no merit to the “genetic hypersusceptibility” and “mercury efflux disorder” theories proposed by Dr. Aposhian and the petitioners.
It is useful to note that Nataf hasn't published on autism since, and Lathe seems to have moved on as well, publishing his last article on autism in 2009