New experiments performed on roundworms reveal that a typical plastic additive inhibits DNA synthesis and produces egg cells with multiple chromosome errors. The study by Monica Colaiácovo of Harvard Medical School was published in the journal PLOS Genetics on October 24.
Benzyl butyl phthalate (BBP) is a plasticizer which is used to soften and strengthen plastic products, and it is widely used in food packaging materials, cosmetics and toys for children. Some earlier research has revealed that BBP has an influence on human hormones and human reproduction and development, and yet the mechanism has remained comparatively obscure.
In the new work, the authors exposed the worms to various concentrations of BBP and examined whether the chemical induces irregularities in the eggs. They found that, as in humans, at these levels BBP disrupts the segregation of newly duplicated chromosomes into the sex cells.
In particular, the BBP affects genes as well as egg cells showing mutation, oxidative stress and DNA strands breakdown that results in cell death as well as egg cells that have the wrong number of chromosomes.
According to the present work of the researchers, exposure to BBP may affect gene expression and its results in severe DNA damage which contributes to producing poor quality egg cells with the wrong number of chromosomes.
The same study also highlighted that like the mammalian system, C. elegans also metabolises BBP and its levels affect worms at BBP concentrations that are measurable in humans. All that can be said is that the present work adds weight to the evidence that this very popular plastic component is toxic and destructive to animal reproduction.
The authors conclude, “Here, demonstrated in the OVC-‘based system’ is the importance of what, in the nematode C. elegans , this study showed is that exposure at a level within the range of that detected in human serum and urine alters germline gene expression; the effect is to associate increased germline oxidative stress with compromised genomic integrity and errors in meiotic chromosome segregation.”
Reference: Henderson AL, Rajendiran Karthikraj, Berdan EL, Sui SH, Kannan K, Colaiácovo MP. Exposure to benzyl butyl phthalate (BBP) leads to increased double-strand break formation and germline dysfunction in Caenorhabditis elegans.
