Ear To The Ground

Scented consumer products emit over 100 different VOC's; some are carcinogenic

For those of us acquainted with researchers examining VOC exposure to individuals from scented consumer products (for example, at U.C. Berkeley and at U.C. Medical Center in San Francisco), it comes as no surprise that there is a bouquet of VOC's wafting into homes and work places.  However, researchers have recently undertaken a survey of 25 scented products (air fresheners, laundry detergents, fabric softeners, dryer sheets, disinfectants, dish detergents, all-purpose cleaners, soaps, hand sanitizers, lotions, deodorants, and shampoos) and identified that over 100 different VOC's are being emitted, a figure that is surprising in its scope.  Even products advertised as “green,” “natural,” or “organic” emitted as many chemicals as standard ones.

Even more troubling is the utter lack of disclosure.  The researchers found 133 unique VOC’s identified among 25 products, and that 24 of these are classified as toxic or hazardous under at least one federal law.  Only 1 of the 133 was listed on any label, and only 2 of the 133 were listed on any MSDS sheets.  The researchers found the average number of VOC's emitted per product was 17.  Each product emitted 1–8 toxic or hazardous chemicals, and close to half (44%) generated at least 1 of 4 carcinogenic hazardous air pollutants (acetaldehyde, 1,4-dioxane, formaldehyde, and methylene chloride).  These hazardous air pollutants have no safe exposure level, according to EPA.  Of the 133 VOC's detected, only ethanol was listed on any label (for 2 products), and only ethanol and 2-butoxyethanol were listed on any Material Safety Data Sheet (for 5 products and 1 product, respectively).

Further, the potential for health impacts is not abstract nor necessarily associated with the VOC's present in the product.  For example, a single fragrance in a product can contain a mixture of hundreds of chemicals, some of which (e.g., limonene, a citrus scent) react with ozone in ambient air to form dangerous secondary pollutants, including formaldehyde (a known human carcinogen).  Thus, the potential exposure picture is more complex than the mere presence of specific VOC's.

Manufacturers are required by FDA (which regulates personal care items) to list the term “fragrance” on product labels, but not MSDS's, although they do not need to disclose the ingredients of those fragrances.  Manufacturers are not required by the Consumer Product Safety Commission (which regulates cleaning supplies, air fresheners, and laundry products) to list either the term “fragrance” or fragrance ingredients on labels or MSDS's.  The Household Product Labeling Act, currently under review in the U.S. Senate, would require manufacturers to label consumer products with all ingredients, including fragrance mixtures.

It is important to note that at present there is a lack of good toxicological data on the threat posed by such exposure.  It may be minimal; it may help create a risk.  A good example of the range of risk derives from some studies undertaken many years ago in the context of Proposition 65 litigation.  It was found that while customers in nail saloons were not exposed to dangerous levels of chemicals, the workers in the saloons were.

The report can be found at http://dx.doi.org/10.1016/j.eiar.2010.08.002.   

 

Decline of Western Aspen trees swells population of rodents that carry the deadly sin nombre virus

As noted in prior posts, Aspen trees in the West have been dying.  There appears to be no single cause.  However, drought in the 1990's and early 2000's probably made the trees more susceptible to cankers, fungi, and other maladies.  The result is that some sites have lost as much as 2/3 or more of their Aspen trees.

In areas that have been particularly hard hit by the die-off of trees researchers have found that there is an explosion of deer mice.  Unfortunately, deer mice are a major vector for the sin nombre virus aka hantavirus.  Infected mice manifest few outward signs, but humans inhaling the virus from mouse urine or saliva become infected.  The disease then moves forward to what is known as the hantavirus pulmonary syndrome.  Unknown to medicine until 1993, hantavirus pulmonary syndrome starts with muscle aches, chills, fever, and stomach upset.  Later, fluid fills the lungs; more than a third of victims have died.  In 2010, the CDC logged 560 cases in 32 states stretching from California to Maine, but mostly in the West.

This is another example of repercussions that flow from rapid changes to and from fragmentation of the environment.  Such changes can have deadly adverse consequences for humans.

The study results were report at the January 4, 2011 meeting of the Society for Integrative and Comparative Biology.  Unfortunately, the results have not been published.  An earlier paper about a like topic by the same researchers can be found at http://www.ingentaconnect.com/content/klu/442/2008/00000155/00000003/00000922.

Saccharin is no longer a hazardous waste (really)

On December 17, 2010, EPA published a final rule to remove saccharin and its salts from the CERCLA list of hazardous substances and the RCRA list of hazardous wastes.  EPA's listing of saccharin as a hazardous waste under RCRA was the sole basis for its listing as a hazardous substance under CERCLA; therefore, since EPA has removed saccharin's listing as a hazardous waste, there is no longer reason for it to be listed as a hazardous substance under CERCLA.

Persons in charge of vessels or facilities from which saccharin or its salts are released will no longer be required to immediately notify the National Response Center of the release under CERCLA Section 103 and will not be subject to the liability provisions under CERCLA Section 107.

For more information, see http://www.epa.gov/waste/hazard/wastetypes/wasteid/saccharin/.

California sets forth indicators of disproportionate impacts of climate change on environmental justice communities

To assist Cal-EPA with the examination of potential environmental justice concerns associated with climate change, Cal-EPA requested the Office of Environmental Health Hazard Assessment (OEHHA) [best known for its role in setting drinking water related Public Health Goals and in overseeing much of the Proposition 65 regulatory activities in California] to develop indicators describing disproportionate impacts of climate change on "certain" California communities.  The OEHHA report was just published.

What are the indicators of climate change that can be ascertained in California?  Among other changes, the report notes the following:  1) spring snowmelt volumes are declining [California is very dependent on snowmelt as a water resource]; 2) glaciers in the Sierra Nevada are decreasing in size; 3) sea level is rising [USGS folks that I know pointed out to me years ago that all the gauges they happen to monitor showed an ongoing increase in sea levels]; 4) large wildfires are becoming more frequent; and, 5) habitat ranges of certain plant and animal species are shifting [this latter point has been noted in many prior posts].

What then are the disproportionate impacts on low-income and minority communities?  Among other impacts the report notes the following four indicators: (1) low-income families and individuals are less likely to live in home with air conditioning, and electricity costs for cooling are a greater proportion of household income compared to more affluent households; (2) because summertime extreme heat since the mid-1980's appears to be trending upward (as shown by certain agricultural stations), farm workers are likely to experience disproportionately greater exposure to extreme heat; (3) low-income residents and minorities are more lively to live in urban neighborhoods with large impervious areas and minimal tree canopy, which intensify summertime heat; and, (4) rural poor living at wildland-urban interfaces may have less capacity and resources to take measures to prevent and fight wildfires and to recover from wildfires.

A copy of the report can be downloaded from: http://www.oehha.org/multimedia/epic/epic123110.html.   

Amphibians face threats from chemicals across the landscape

Numerous prior posts have noted various theories and evidence for the reduction in number of frogs found in various environments.  Taking a step back from focusing on agricultural lands and practices, some researchers are surveying the presence of frogs, including intersex frogs (those with both male and female characteristics) in a variety of landscapes, including woodlands, suburban yards, and urban settings.

Some studies to date have indicated that intersex frogs and other adverse impacts are quite likely to be found in suburban and urban settings.  Though causation has not been identified, several theories have been developed.  For example, it is well known that there may be heavy chemical usage in suburban settings (e.g., lawn and yard care, such as atrazine and the fungicide chlorothalonil).  In other areas, evidence of contaminated ponds appears to be the result of leakage from both sewer lines and from septic systems (e.g., shown by the presence of common indicator chemicals such as caffeine).  Since it is well known that many prescription drugs, including contraceptives, are flushed when no longer needed or being utilized, such leakage could expose frogs and other wildlife to a wide variety of drugs and chemicals.  [This is another reason why take-back programs for prescription drugs are gaining in popularity.]

Other research suggests that earlier studies may have missed key factors.  For example, the death rate of tadpoles was higher in glyphosate impacted runoff that has the scent of predators (such as dragonflies) than runoff without such a scent.  Further work pointed to the depth of the water into which the runoff ran as an important factor; survival rates went up in deeper waters even when the scent was present.  Thus, the configuration of the impacted water body can have a significant influence on the outcome. 

Thus, understanding in a broad ecozone context what is impacting our bug-eating proverbial canaries in the coal mine is, not surprisingly, a more complex question than has been assumed.

Studies about these and related matters can be found at http://www.pnas.org/content/104/21/8897.full, http://www.crcnetbase.com/doi/abs/10.1201/9781439817957-c5, http://onlinelibrary.wiley.com/doi/10.1111/j.1749-6632.2009.04453.x/abstract, http://www.springerlink.com/content/g16n23867h1172x0/, and http://www.epa.gov/opp00001/reregistration/atrazine/.

Lead and cadmium may delay the onset of puberty in girls

Violation of lead and cadmium standards are often used in litigation under California's Proposition 65 because the threshold warning level, based on "reproductive toxicity", requires the potential ingestion of very small amounts.  The general toxicity of lead and cadmium are well known; see for example http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~CGoBJV:1:human and http://toxnet.nlm.nih.gov/cgi-bin/sis/search/f?./temp/~OGv2YK:1:human.

Now researchers have identified a link between relatively low levels of these metals and hormone markers of delayed onset of puberty in girls.  Researchers took blood samples from young girls and measured concentrations of two reproductive hormones (inhibin B and luteinizing hormone) that serve as markers of hypothalamic, pituitary, and gonadal functioning.  The researchers found no significant associations between blood lead and cadmium and luteinizing hormone.

However, girls aged 10 or 11 with blood lead levels of 5 μg/dL or higher were 75% less likely than girls with blood lead under 1 µg/dL to have levels of inhibin B greater than 35 pg/mL, a level typically deemed consistent with puberty by the limited research in this area.  The researchers also found proportionately lower levels of inhibin B in girls who had relatively high levels of both cadmium and lead, compared with girls who had only high lead.  Moreover, after adjusting for age, inhibin B levels were lowest for iron-deficient girls with blood lead levels of 1 µg/dL or higher, suggesting that lead may be particularly toxic for girls with iron deficiency.

The researchers conclude that lead may suppress the production of hormones associated with puberty, especially in concert with cadmium.  They stress that, on a national scale, changes in the timing of onset and/or progression of puberty can have considerable public health and social implications for both boys and girls.  For instance, relatively late-maturing girls are at risk for diminished bone strength and fragility fractures later in life.  The researchers also noted that the hormone alterations linked to lead and cadmium exposure in the study could have other as-yet unknown effects.

The study can be found at http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info%3Adoi%2F10.1289%2Fehp.1001943.

Silver nanoparticles are transformed by sewage treatment

Prior posts have noted a number of issues related to nanoparticles.

Silver nanoparticles are used in hundreds of consumer products, including food storage containers, clothing, computer keyboards, cosmetics, pillows, cell phones, and medical appliances, because of their antimicrobial properties.  Because silver is water soluble, it washes out some products, which sends the nanoparticles into wastewater systems.

Researchers sought to examine what transformations, if any, occurred in the sewage treatment system.  They determined that sewage sludge samples which were tested were high in silver, but that the silver could not be attributed to an industrial source.  Scanning transmission electron microscopy revealed the nanoparticles were 5–20 nm in diameter and formed small, loosely packed aggregates no more than 100 nm in size.  Energy-dispersive X-ray spectrometry showed that sulfur (which is produced by microorganisms that digest sewage) combined with the silver in a 2:1 ratio, and the crystal structure confirmed the formation of silver sulfide nanoparticles as part of the sewage treatment process.  No pure silver nanoparticles were found.

What does this portend?  Currently, there is a dearth of knowledge about silver sulfide nanoparticles.  Their solubility, bioavailability, toxicity, and reactivity are unknown.  These are not mere academic questions because sewage sludge is, in some cases, applied to land.

The study can be found at http://pubs.acs.org/doi/abs/10.1021/es101565j and at http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&cmd=Search&doptcmdl=Citation&defaultField=Title%20Word&term=Kim%5Bauthor%5D%20AND%20%20AND%20Environ%20Sci%20Technol%5BJournal%5D%20AND%202010%5BPublication%20Date%5D%20AND%207509%5BPagination%5D.

Will DNA analysis begin to substitute for actuarial tables in wrongful death and disability cases?

In wrongful death cases and in cases involving permanent injuries that require a life-time to care, it is common for estimates to be made of the "value of the life" or "time needed for care" from actuarial tables that allegedly reflect the particulars of the plaintiff.  However, with the growing sophistication of genetic analysis, will actuarial tables become a thing of the past?

Researchers recently announced that they had tentatively identified genes that appear to contribute to a long life.  Will similar assessments be done to ascertain if one has a shortened life written in one's genes?

The issue is, of course, much more complicated than one's genes.  Prior posts have noted the interaction between genes and the environment, particularly in the form of methylation.  [See, for example, http://en.wikipedia.org/wiki/Methylation.]  It is this interplay that tends to explain, at least in part, why identical twins often do not have the same health outcomes even when their lifestyles are similar, but not identical.  Further, as the researchers note, such genetic assessments are a partial explanation, at best.  A healthy lifestyle and other environmental factors play a very important role in one's ultimate length of life.

It is thus too early to believe that genetic assessments will substitute for actuarial tables in the near future.  But, as the assessments become more sophisticated, they may provide another piece of information for triers of fact to consider.

Information on the New England Centenarian Study and the report on genes and lifespan can be found at http://www.bumc.bu.edu/centenarian/overview/ and http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/07/02/MNHL1E87PC.DTL&type=health.

Atrazine is being subjected to a reevaluation since prior EPA studies during the reregistration process appear to have ignored hormone disruption and exposure studies

Atrazine, a triazine herbicide, stops pre- and post-emergent weeds by inhibiting electron transport, ultimately blocking photosynthesis.  [More about the quantum mechanical properties of photosynthesis will be noted in a subsequent blog.]  EPA reexamined data on the herbicide’s putative toxicity four years ago as part of a systematic review of the safety of older pesticides, those initially registered for use before 1984.  Atrazine was reregistered, which meant that it could continue to be sold.  As part of this review, EPA concluded that Atrazine’s regulated use could continue without posing undue risks to health and the environment.  Yet, the pesticide is banned by the European Union and, ironically, in Switzerland, where Atrazine’s leading manufacturer, Syngenta, is headquartered.  I have known a number of amateur vintners that have been using Atrazine in their vineyards for at least the last 3 decades.

 

In recent years, however, questions have surfaced about Atrazine’s safety, especially after monitoring programs picked up the chemical in drinking water and lab studies demonstrated the pollutant’s ability to feminize and even deform amphibians and fish.  Last fall, EPA announced it was reopening an inquiry into allegations of Atrazine’s risks.  EPA instructed its Scientific Advisory Panel on pesticides to reevaluate the weed killer’s safety through three meetings this year, the first of which took place in February 2010.  The panel will review human data and any studies, including animal or test-tube assays, that might suggest risks to people.  See http://www.epa.gov/opp00001/reregistration/atrazine/.

 

Among the criticisms was a report in August 2009 by the Natural Resources Defense Council: “Poisoning the Well: How the EPA is ignoring atrazine contamination in surface and drinking water in the central United States.”  The NRDC analysis of data that the EPA had collected, but had not publicly released, showed that traces of atrazine frequently polluted not only rivers but also water exiting the tap, oftentimes at concentrations exceeding EPA’s 3-parts-per-billion limit for drinking water.  See http://www.nrdc.org/health/atrazine/default.asp.

 

For its part, Syngenta Crop Protection, based in Greensboro, N.C., the largest U.S. producer of atrazine, has argued that EPA’s new review is unnecessary because it has been subjected to seven Scientific Advisory Panels, 15 years of special review, and the reregistration process in 2006.

 

While the comments of Syngenta have some merit, there would appear to be considerable new data that have not, for some bizarre reason, previously been part of any systematic federal review.  One of the areas that appears to be under-explored is the impact of Atrazine on hormone disruption, including in humans.

 

As they say, stay tuned.

EPA proposes major reduction in mercury emissions from boilers, process heaters, and solid waste incinerators

Prior posts have noted mercury emissions from coal, transnational movement of mercury in the atmosphere, and the methylation process of mercury in the environment.

EPA has issued proposals that allegedly will reduce mercury emissions by half from roughly 200 thousand boilers, process heaters, and solid waste incinerators.  Boilers and process heaters are the second largest emitters of mercury in the U.S.  The annual cost of installing and operating the control technology is estimated to be $3.6 billion.  EPA alleges that the health benefits will be in the range of $18 to $44 billion annually, with a reduction of 1,900 to 4,800 deaths and 33 thousand asthma attacks annually, among other health benefits.

EPA will take comments on the proposals for 45 days.

An announcement of the new controls can be found at http://yosemite.epa.gov/opa/admpress.nsf/d0cf6618525a9efb85257359003fb69d/74ef19ce603f20548525771500507938!OpenDocument.  The proposed regulations and fact sheets can be found at http://www.epa.gov/airquality/combustion/actions.html.