The Precautionary Principle at work

BBC NEWS | Science/Nature | Warming set to ‘devastate’ coral

Bleaching in 1998 occurred in all reef regions of the world; 16% of the world’s reefs were lost in that one year, alone. But the western Indian Ocean suffered most because of an interaction between El Nino and another periodic climate phenomenon called the Indian Ocean dipole.

In the seven years since, the damaged reefs have been largely unable to reseed. Many simply collapsed into rubble and became covered in algae.

This collapse removed food and shelter from predators for a large and diverse amount of marine life. The survey showed four fish species could already be locally extinct, and six species are at critically low levels.

The survey also revealed that the diversity of fish species in the heavily impacted sites had plummeted by about 50%.

Well, this is bad news, there has been earlier indication that coral reefs were not necessarily doomed by higher ocean temperatures because this would just cause a shift in the coral species to varieties thriving at higher temperatures/exhibiting adaptive behaviors. Obviously, this did not happen fast enough to regenerate the reef.

Chemical & Engineering News: Latest News – Cigarettes’ Smoking Gun?

Acrolein, one of the 4,000 constituents of cigarette smoke, has been found unexpectedly to cause DNA damage in the gene for the infamous tumor-suppressor p53, which is often disrupted by cancer. In particular, the pattern of DNA mutations caused by acrolein mimics what is often found in human lung cancer samples (Proc. Natl. Acad. Sci. USA, DOI: 10.1073/pnas.0607031103).

“If cigarette smoke is the weapon that causes lung cancer, then these mutations are fingerprints on the knife,” says author Moon-shong Tang of New York University School of Medicine, in Tuxedo. Tang was also involved in identifying another cigarette-smoke component that can induce such mutations: a metabolite of a polycyclic hydrocarbon called benzo[a]pyrene. Acrolein is present in cigarette smoke in levels of up to 1,000 times greater than benzo[a]pyrene.

So, if you remove acrolein from tobacco smoke, does that make for a much safer smoking experience? Is this a research question worth answering? FYI, I watched Thank You for Smoking last night, so, fresh on my mind!

Yes, strained headline!

A Toxic Hand-Me-Down — Balter 2007 (327): 1 — ScienceNOW

Environmental contamination can cause cancer and birth defects. Of particular concern are a group of toxic chemicals called endocrine-disrupters, which interfere with reproductive hormones and may cause sterility. A new study, published online this week in the Proceedings of the National Academy of Sciences, suggests that these chemicals can change reproductive behavior as well, and that these behavioral changes can be passed on from parents to offspring. If correct, these changes could alter the course of evolution by giving natural selection new targets to act on.

In 2005, a team led by reproductive biologist Michael Skinner of Washington State University in Pullman reported in Science that the fungicide vinclozolin, an endocrine-disrupter used to spray vineyards and other crops, causes fertility defects in the male offspring of female rats treated with the chemical. These defects are, in turn, passed down to the males of subsequent generations. The toxin did not appear to be altering gene sequences; instead, Skinner and colleagues found, vinclozolin was somehow causing other chemical groups to latch onto certain genes, changing their expression (Science, 3 June 2005, p. 1391). The phenomenon is known as epigenetic inheritance. Last year, Skinner’s group identified 15 epigenetically altered DNA sequences in the sperm of the vinclozolin-treated rats

More signs of intergenerational effects of low levels of endocrine disruptors. I had blogged recently about Bisphenol A having intergenerational effects (where exposure to a chemical agent causes consequences for offspring and off off spring, etc).

It’s still early, but remember Children of Men (good movie, see it).

Leftovers may explain perfluorinated compound puzzle:

See my earlier post about this. Looks like the EPA did want the companies to phaseout not just the PFOA, but the precursor compouds as well, and according to this article, quite a bit of progress has been made.

Eight companies have pledged to slash releases of several perfluorochemicals at their operations around the world, EPA announced on March 2.

Arkema, Asahi, Ciba, Clariant, Daikin, DuPont, 3M/Dyneon, and Solvay Solexis have agreed to reduce emissions of perfluorooctanoic acid (PFOA), its longer chain homologs, and compounds that can degrade into PFOA, EPA said. The companies will also reduce levels of these compounds in their products. Responding to a challenge EPA made in January, the eight firms volunteered to cut industrial releases of PFOA as well as amounts of the chemical in products 95% from 2000 levels by 2010 or earlier. The companies also pledged to work on eliminating releases and content of PFOA in products by 2015.

Here are the individual companies’ commitment letters. They all loudly proclaim their commitment to reduce PFOA levels in their products, not quite so universally unequivocal on the precursors… I need a lawyer to parse some of the language. 3M, for instance, says that they do not “manufacture” the telomers’, which is not the same as saying they do not use them. Solvay Solexis, is extremely straigtforward and agrees to the EPA conditions in a letter actually written in plain English! Dupont, good letter too. Let’s see how this situation plays out, outright elimination in 10 years seems nice, which leads me to believe that the companies are already moving in this direction. The journal article suggests that the residuals are mainly due to inefficiencies in the manufacturing process. The reaction yield is 70%, meaning the 30% left behind from the monomer formation reaction will need to be removed from the product.