EDF Health

New study demands far more than a pregnant pause: Expectant women carry dozens of toxic chemicals in their bodies

By / Published: January 14, 2011

Richard Denison, Ph.D., is a Senior Scientist.

A long-awaited study documenting the presence of multiple toxic chemicals in the bodies of pregnant women was published today in Environmental Health Perspectives.  The study, conducted by researchers at Program on Reproductive Health and the Environment at the University of California, San Francisco, analyzed the most recent comprehensive biomonitoring data collected by the Centers for Disease Control (CDC) as part of its national human biomonitoring program.

The new study found widespread exposure of pregnant women to a large fraction of the chemicals for which biomonitoring is conducted, including chemicals that are currently in widespread use, such as brominated flame retardants (known as PBDEs) used in furniture foam and plastics, perfluorinated chemicals (PFCs) used in everything from packaging to textiles, and a pervasive environmental contaminant used in rocket fuel (perchlorate).

In particular the study noted:  “Certain PCBs, organochlorine pesticides, PFCs, phenols, PBDEs, phthalates, polycyclic aromatic hydrocarbons (PAHs) and perchlorate were detected in 99 to 100% of pregnant women.” (emphasis added)  Read More »

Also posted in Emerging science, Perchlorate / Tagged , , , , , , , , , , , | Read 1 Response

Hitting ’em where it hurts: BPA reduces sperm quantity and quality in male workers

By / Published: October 28, 2010

Richard Denison, Ph.D., is a Senior Scientist.

As reported by Rob Stein in the Washington Post this morning, a NIOSH-funded study of male Chinese workers conducted by researchers at Kaiser-Permanente in Oakland, California has found that exposure to the endocrine-disrupting chemical bisphenol A (BPA) significantly increases the incidence of low sperm counts and concentrations, as well as lowered sperm motility and higher mortality.

The 5-year study, published in the peer-reviewed journal Fertility and Sterility (that’s a title only slightly more cheery than the CDC’s publication Morbidity and Mortality!), shows that the same kinds of adverse effects of BPA on sperm already observed in animal studies also occur in humans with detectable levels of BPA in their urine.

And while the most pronounced effects were observed in highly exposed workers, the authors of the study note:

Similar dose-response associations were observed among participants with only environmental BPA exposure at levels comparable to men in the general United States population.

Despite a markedly reduced sample size in this group of men exposed only to low environmental BPA sources, the inverse correlation between increased urine BPA level and decreased sperm concentration and total sperm count remain statistically significant.

Read More »

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New EPA data: Dispersant likely not increasing acute lethality of oil in BP oil disaster

By / Published: August 2, 2010

Richard Denison, Ph.D., is a Senior Scientist.

I had reported in an earlier post – based on data provided to EPA by Nalco, the maker of Corexit® 9500, the main dispersant being used in the Gulf – that the dispersant appeared to increase the acute aquatic toxicity of oil.

At a press conference today, EPA released data from the second round of its own testing on Corexit 9500 (and seven other dispersants), and concluded that the acute toxicity of the dispersant-oil mixture is about the same as the oil by itself.

What explains the discrepancy?  To put it most simply:   It’s not that the dispersant-oil mixture was less toxic in the EPA tests, it’s that the oil EPA used – which is the actual oil that has been leaking into the Gulf – was more toxic than the fuel oil Nalco had used.  Here’s a cartoon illustrating what I’m saying (the arrow shows the biggest change):

So the good news is that the dispersant doesn’t appear to be increasing the acute aquatic toxicity of the oil released into the Gulf.  The bad news is that the oil is pretty toxic, and the dispersant certainly doesn’t help directly with that.  And of course, the bigger questions about longer-term effects of dispersants and dispersed oil are not addressed by the new data.   Read More »

Also posted in Environment / Tagged , | Read 4 Responses

Exceptions swallow the rule: “Rare cases” turn into daily approvals for dispersant use

By / Published: July 7, 2010

Richard Denison, Ph.D., is a Senior Scientist.

What the EPA hath sought to take away from BP, the US Coast Guard hath given back.

Remember the May 26 Directive that, well, directed BP to “eliminate the surface application of dispersants” except in “rare cases when there may have to be an exemption” and where BP submits a written request and receives an exemption in writing from the Federal On-Scene Coordinator (FOSC, currently Admiral James Watson of the Coast Guard)?

Naturally, I was curious about the nature and number of such exemptions, given that, as I noted earlier, surface application of dispersants has continued since the May 26 Directive.  After I (and others, I expect) made inquiries a couple of weeks ago to get copies of the written requests from BP and written approvals from the FOSC, the Coast Guard has informed me that it has posted these documents on the Deepwater Horizon response website.

These documents reveal that, as of June 30 (the last day for which a document has been posted as of this writing), more than 40 exemption requests have been submitted – and approved.  These exemptions have allowed surface application of dispersant to occur virtually every day since the Directive was issued.

The documents also hold some other interesting details as to the rationales offered for the exemptions and the nature of the approvals.  Read More »

Also posted in Environment, Health policy, Regulation / Tagged , | Read 3 Responses

Not so fast: Why dispersants EPA ranks as “practically non-toxic” are still a concern

By / Published: July 2, 2010

Richard Denison, Ph.D., is a Senior Scientist.

To judge by the headlines and leads of stories that ran on the websites of the New York Times (“The E.P.A. on Dispersants: Cure Is Not Worse Than the Disease”) and the Washington Post (“Oil dispersant does not pose environmental threat, early EPA findings suggest”) reporting on an EPA conference call held Wednesday, you’d think the first round of test results on dispersants conducted by EPA answered all outstanding questions and gave their use a clean bill of health.

Hardly.  (Despite the misleading headlines and leads, the rest of these stories were more nuanced and more accurate.)

As I reported in a post Wednesday, the new acute toxicity data were from tests conducted on the dispersants by themselves, rather than mixed with oil – which is what the environment sees.  Moreover, the new data did little more than confirm already available data showing that currently listed dispersants exhibit relatively low acute toxicity to fish and shrimp, and that by themselves they are less toxic than oil by itself.

So despite the hoopla, the new data from this first round of testing are of very limited utility in answering any of the more profound questions surrounding the use of dispersants.  Read More »

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Katrina chronicles meet the BP oil disaster: Formaldehyde-laced trailers are back in the Gulf

By / Published: July 1, 2010

Richard Denison, Ph.D., is a Senior Scientist.

In another truly bizarre collision between recent Gulf coast disasters (on top of Hurricane Alex), Ian Urbina of the New York Times reports on the front page today that those toxic trailers – sold at auction by FEMA back in March – have been reincarnated once again, this time as housing for Gulf cleanup workers.

I had blogged about the sale at the time, questioning the viability of FEMA’s assurance that “wholesale buyers from the auction must sign contracts attesting that trailers will not be used, sold or advertised as housing, and that trailers will carry a sticker saying, ‘Not to be used for housing’.”  In that post, I had cynically asked:  “Think that’s likely to be enough?”

With good reason, it turns out.  Read More »

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