A pair of papers about the risks of titanium dioxide nanoparticles that share many of the same authors has been retracted from a toxicology journal following an investigation at Soochow University in China.
Particle and Fibre Toxicology is retracting the papers for problems with the statistical methods and missing data, as well as for sharing figures.
Here’s the note for “Intragastric exposure to titanium dioxide nanoparticles induced nephrotoxicity in mice, assessed by physiological and gene expression modifications:”
This article [1] has been retracted by the Editor. A committee at Soochow University has investigated this case and supports the decision to retract the article. Incorrect statistical methods were used to calculate mean and S.D. values and additional errors were made in determining 8-OHdG concentrations. The committee also found that some of the original data were missing. We apologize to the readership of Particle and Fibre Toxicology.
The paper has been cited 25 times, according to Thomson Scientific’s Web of Knowledge.
The retraction note for “Mechanisms of nanosized titanium dioxide-induced testicular oxidative stress and apoptosis in male mice” is pretty similar, with an added sentence about the figure duplication from the other paper. Here’s the note:
This article [1] has been retracted by the Editor. A committee at Soochow University has investigated this case and supports the decision to retract the article. Incorrect statistical methods were used to calculate mean and S.D. values and additional errors were made in determining 8-OHdG concentrations. It has come to light that Figure 1 and Figure 2 were published in a previous article[2]. The committee also found that some of the original data were missing. We apologize to the readership of Particle and Fibre Toxicology.
The paper has been cited once, according to Thomson Scientific’s Web of Knowledge.
The Editor in Chief of the journal, Flemming Cassee, told us that he was alerted to the problems by other researchers. He explained:
Unfortunately it’s not only the two papers in PFT but we have identified more papers in where data are too beautiful to be true, levels of DNA damage markers are clearly out of range and in which histology pictures have been used in more than one study but with different toxicants….The authors could not explain the exceptional findings and the senior author admitted that many things had go wrong.
We asked if those other papers were also in the journal. Shane Canning, Media Manager at BioMed Central, which publishes the journal, got back to us with this statement:
We can confirm that two articles were retracted from Particle and Fibre Toxicology following an investigation by the authors’ institute about concerns raised around the data presented and errors in the statistics. Our own investigation found that there were no other articles in Particle and Fibre Toxicology or other BioMed Central journals by this group of authors have been affected. We do not comment or speculate on articles published in journals from other publishers.
Fashui Hong, an author on both of the Particle and Fibre Toxicology papers, has a correction on an article in Toxicological Sciences, “Gene Expression in Liver Injury Caused by Long-Term Exposure to Titanium Dioxide Nanoparticles in Mice”:
A reader identified a problem with the standard errors in one of the tables. The standard errors in Table 1 were presented as values equal to 5% of the mean, rather than the actual standard errors, due to an incorrect setting on the statistical package used to analyze the data. The authors have since provided the original data with the actual standard error values. The corrected table is shown below.
We identified a problem with the 2012 paper and investigated this according to COPE guidelines. The published correction was the result of that specific concern. We are aware that other papers from this group have recently been retracted by other journals. We continue to collect information about this laboratory and consider it to be an ongoing examination of the integrity of the work published in our journal.
We contacted Soochow University and got this autoreply back:
Thanks for your letter. we’ll deal with it soon.
We’ve contacted the corresponding authors on both papers (one of which is Hong), and we’ll update if we hear back.
Hat Tip: Rolf Degen
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