“That is a profound observation,” Benninghoff said.
Third generation female rats also showed an increase in ovarian disease, which is consistent with previous studies.
For male rats, kidney disease was significantly higher in the third generation rats whose ancestors were exposed to dioxin, the first time such a finding has been reported. Twenty-seven percent of the third generation male rats had signs of kidney damage, compared to about 9 percent of the control group.
Third generation female rats also had a higher incidence of multiple diseases or abnormalities per rat.
Complicating matters, the rats directly exposed to dioxin had different disease profiles than later generations, so “one cannot necessarily predict possible disease outcomes in future generations by observing individuals that were directly exposed,” Benninghoff said.
Sperm from the great-grandkids – the first generation without direct dioxin exposure – had telltale modifications in gene expression in 50 regions of DNA as a result of their ancestors’ dioxin exposure, Skinner said. These regions can be used as “biomarkers for ancestral exposures and disease,” he said. That means researchers could use these regions as a road map to trace dioxin exposure through generations.
The study focused on TCDD, but Skinner speculated that all dioxins would behave the same way, but that remains to be studied.
Other environmental chemicals also have transgenerational effects in lab animals, including BPA, phthalates, the pesticides permethrins, vinclozolin and methoxychlor and the insect repellent DEET.
The American Chemistry Council, which represents chemical companies, did not return a request for comment.
This article originally ran at Environmental Health News, a news source published by Environmental Health Sciences, a nonprofit media company.
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4 Comments
Add CommentWhat I like is the United States has finally admitted to cleaning up Agent Orange in Viet Nam but they have not publically admitted to paying Vietnamese for dioxin related diseases which they refuse for US veterans.
Reply | Report Abuse | Link to thisWashington State (U) the biggest user of bond(whitepaper)= Dioxin.
Reply | Report Abuse | Link to thisThe following statement regarding the Seveso study is in error:
Reply | Report Abuse | Link to this"A study of a 1976 industrial accident in Anshu Seveso, Italy, documented health defects in the grandchildren of women that conceived as long as 25 years after exposure to dioxin."
This links to Bacarelli et al. (2008), which DID NOT look at health defects in the grandchildren of the exposed women of Seveso, but thyroid hormone levels in the CHILDREN (neonates) born to a group of exposed Seveso women. The objective was to determine if there was an association between exposure to dioxins in post-pubescent women and congenital hypothyroidism in their offspring. As such, the Bacarelli investigation is not a study of human epigenetics as implied by Mr. Israel and Scientific American.
It is what has been called the benevolent affects of unfettered free enterprise. The use by Hearst of unprincipled lies and exaggerations caused the move away from hemp to wood for the production of paper. The unfettered paper companies had to use harsh chemicals to overcome the stiffness of wood. Wood, afterall, does have to support 100 foot high trees. These harsh chemicals produced dioxen as a by-product. Some of it was left in the paper. So, when dumped in the water fish became contaminated with dioxen, and when papers were incinerated dioxen became airborne. Hundreds of thousands of persons took in dioxen, many of whom got cancer. The results of unfettered free enterprise. Making superior paper from hemp produces no toxins.
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