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

[Note:  This post was originally posted as a comment on Gina Solomon's blog post on Huffington Post.  The context is a pending budget proposal from the Governor's office in California to eliminate the State's Office of Environmental Health Hazard Assessment (OEHHA) under CalEPA and disperse some but not all of its functions to other agencies.  This proposal, if implemented, would in my view be truly tragic.  If you agree, make your voice heard!]  Read more »

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

Some months ago, my colleague John Balbus posted here about studies finding that when multi-walled carbon nanotubes (MWCNTs) are injected into the abdominal cavities of mice, they induce inflammation and mesothelioma-like reactions similar to those caused by asbestos.  He appropriately cautioned that - among other critical questions - these studies had not demonstrated that inhaled MWCNTs could actually move out of the lung and into the tissues where asbestos gives rise to its effects.  Well, that particular dot now appears to have been connected. Read more »

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

It's been nearly a year since EPA launched its voluntary Nanoscale Materials Stewardship Program (NMSP) - and over three years since EPA was urged, by a diverse group of stakeholders, to do so only in conjunction with the development of mandatory reporting rules as a backstop and to limit the duration of the basic part of the program to at most six months.

EPA ignored that advice, and proceeded with an open-ended voluntary program and no development of backstop rules.  Now EPA has issued its first evaluation of the NMSP.  So what did EPA find? Read more »

Cal Baier-Anderson, Ph.D., is a Health Scientist.

In 2004, Gunter Oberdorster and colleagues demonstrated that upon inhalation, ultrafine particles, the dimensions of which are measured in nanometers, can move from the nasal passages of rodents to the brain via a specialized nerve called the olfactory bulb.  The evolutionary purpose of the olfactory bulb is to relay information about odors directly and rapidly from the nose to the brain. 

The extent to which rapid transit via the olfactory bulb is a significant potential route of exposure to engineered nanomaterials is still an open question.  But two new papers add support for the relevance of this intriguing exposure pathway, raising important questions regarding the safety of inhaled nanoparticles. 

Read more »

John Balbus, M.D., M.P.H., is Chief Health Scientist.

Some 216 delegates representing 26 countries converged on the largest city in China last week for the 7^th meeting of the International Standards Organization (ISO) Technical Committee (TC 229) on Nanotechnologies.

In China, the turtle symbolizes cosmic order, strength, endurance and wisdom.  In the US, the turtle has come to symbolize slow progress and not keeping up with the times.  Which representation better captures what's going on in ISO's TC 229?   Maybe a little of both. Read more »

Cal Baier-Anderson, Ph.D., is a Health Scientist.

Can nanoparticles get into our drinking water and if so, what's the harm?

Nanoparticles are being used in cosmetics and other personal care products with increasing frequency.  Carbon fullerenes, also known as buckyballs, have recently been touted as imparting age-defying antioxidant benefits when added to skin cream.  And there are some studies that seem to support these claims.  But even if such claimed benefits turn out to be true, this is by no means the end of the story.  Read more »

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

My last post identified two Section 8(e) "substantial risk" notices pertaining to carbon nanotubes, one submitted by BASF, the other by Arkema.  I have in my files one additional Section 8(e) notice for a single-walled carbon nanotube (SWCNT), submitted by DuPont.  With three Section 8(e) notices submitted for different rat pulmonary toxicity studies on carbon nanotubes, it's interesting to compare their results. Read more »

Cal Baier-Anderson, Ph.D., is a Health Scientist.

The manufacture of carbon nanotubes (CNTs) is a very complicated business.  Different production processes leave behind different kinds of metal catalysts, which yield differences in physical and chemical - as well as toxicological - properties of the CNTs.  Read more »

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

Since my first post concerning EPA's Consent Order, I've been reflecting further on the management conditions it imposes - or, more accurately, on what conditions it doesn't impose.  The Order's only such conditions address potential worker exposure.  What about the rest of the nanomaterial's lifecycle? Read more »

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

[Part II of this post is available here.] 

Word hit the street today that EPA intends to make public a "sanitized" version of a Consent Order it has negotiated with a producer of multiwalled carbon nanotubes (MWCNTs).  [A link will be provided once available.]  We obtained a copy of the Order, which has redacted all information claimed confidential by the company involved.  What can we learn from this well-scrubbed Order? Read more »