Remember the Chinese toothpaste scare that broke 2 weeks ago? At the time, the Food & Drug Administration noted that only off-brand products might carry the toxic tainting with diethylene glycol (DEG). Well, now comes word that products carrying the Colgate name might also be affected.
FDA announced that it had confirmed it had identified "counterfeit" toothpaste, imported from South Africa, carrying the Colgate name. It wasn't made by Colgate, but had been fraudulently labeled as such, according to spokespersons for the company. Colgate doesn't have manufacturing plants in South Africa or import toothpaste from there.
Yesterday, Colgate-Palmolive reported that the misbranded product "has been found in several dollar-type discount stores in four states: New York, New Jersey, Pennsylvania, and Maryland. There are indications that this product does not contain fluoride and may contain Diethylene Glycol." Clues that will help recognize these fakes: they're labeled as coming from South Africa and contain misspellings, such as South Afrlca and South African Dental Assoxiation.
DEG, as you may recall, is a solvent commonly used as an anti-freeze. It's poisonous and doesn't belong in anything that makes contact with the mouth. In some developing countries, low-cost DEG is substituted for the more costly glycerin, a popular sweetener used in liquid over-the-counter and prescription-drug products—and now, apparently, in toothpastes as well.
Just a month before the DEG-toothpaste link made news, FDA warned drug manufacturers and health professionals that unscrupulous foreign firms had occasionally been swapping the toxic DEG for glycerin. In one episode last September, in Panama, DEG tainted medicines resulted in 40 deaths.
"Colgate is working closely with the US FDA to help to identify those responsible for the counterfeit product," a company press release announced yesterday. It recommended that consumers who suspect they may have purchased such a fake to call Colgate's toll-free number at (800)-468-6502.
Showing posts with label Environment. Show all posts
Showing posts with label Environment. Show all posts
Friday, June 15, 2007
Tuesday, June 5, 2007
Antifreeze Doesn't Belong in Toothpastes
Few people would knowingly reach for a tube of Chinese toothpaste—at least in a U.S. supermarket, pharmacy, or big-box store. However, a number of bargain brands are, in fact, Chinese imports. And even that wouldn't necessarily be a problem, except that our Food & Drug Administration inspectors have identified several shipments of these Chinese toothpastes tainted with a poison: diethylene glycol (DEG), also known as diglycol.
On June 1, FDA issued an "import alert" about these products" and announced that: "Out of an abundance of caution," it recommends that consumers pitch out away toothpaste labeled as originating in China.
DEG is an antifreeze and solvent used in many commercial resins, dyes, oils and organic chemicals. It's also a "humectant"—an additive that keeps products moist—for tobacco, cork and glues. Although toxic to animals, including humans, China permits the use of DEG in toothpastes. The United States does not. In some of the imported products tested by FDA, DEG constituted 3 to 4% by weight of the toothpastes. Not all of the products were even labeled as containing DEG.
FDA identified about a dozen different brands of tainted toothpastes—none major name brands. Interestingly, none of the contaminated brands had received an American Dental Association Seal of Acceptance either. This is a designation that ADA deems the labeled product safe and effective.
According to FDA, DEG is commonly used in some developing countries as a cheap substitute for glycerin and propylene glycol. Where it has been used in products such as over-the-counter cough syrups and pain relievers, deaths have resulted.
Bottom line: Sometimes it pays to ante up for a name brand, or at least one with a medical group's seal of approval.
On June 1, FDA issued an "import alert" about these products" and announced that: "Out of an abundance of caution," it recommends that consumers pitch out away toothpaste labeled as originating in China.
DEG is an antifreeze and solvent used in many commercial resins, dyes, oils and organic chemicals. It's also a "humectant"—an additive that keeps products moist—for tobacco, cork and glues. Although toxic to animals, including humans, China permits the use of DEG in toothpastes. The United States does not. In some of the imported products tested by FDA, DEG constituted 3 to 4% by weight of the toothpastes. Not all of the products were even labeled as containing DEG.
FDA identified about a dozen different brands of tainted toothpastes—none major name brands. Interestingly, none of the contaminated brands had received an American Dental Association Seal of Acceptance either. This is a designation that ADA deems the labeled product safe and effective.
According to FDA, DEG is commonly used in some developing countries as a cheap substitute for glycerin and propylene glycol. Where it has been used in products such as over-the-counter cough syrups and pain relievers, deaths have resulted.
Bottom line: Sometimes it pays to ante up for a name brand, or at least one with a medical group's seal of approval.
Thursday, May 31, 2007
NASA on Climate Change
Double-speak? Triple-speak? Spin-speak?
Just what was NASA Administrator Michael Griffin trying to tell us in the National Public Radio interview, today, on Morning Edition?
"I'm aware that global warming exists," he flatly admits to NPR's Steve Inskeep. "I understand that the bulk of scientific evidence accumulated supports the claim that we've had about a 1-degree centigrade rise in temperature over the last century . . . I'm also aware of recent findings that appear to have . . . pretty well nailed down the conclusion that much of that is manmade."
Sounds like he's a believer in the message Al Gore has stumped for over the past 2 years (and eloquently articulated in what became the Academy Award winning film, An Inconvenient Truth).
However, where Gore and the science community have largely concluded global warming is bad for the planet, Griffin waffled on his assessment this morning, saying that "Whether [the current global warming trend] is a long-term concern or not, I can't say."
In fact, Griffin took a fairly strange tack in explaining his position to Inskeep, arguing that "To assume that it [global warming] is a problem is to assume that the state of Earth's climate today is the optimal climate, the best climate that we could have or ever have had . . . "
Interestingly, that's not the assumption I've made--nor have heard anyone else make.
Griffin goes on to charge that it's "a rather arrogant position" for people to accord themselves the right "of deciding that this particular climate that we have right here, today, right now, is the best climate for all other human beings."
The problems I find with that line of reasoning is that
1) no one has said today's climate is the best. Indeed, it probably should be a bit cooler than it is today if human habitability is going to be our yardstick. After all, sea-level rise, due to the current global warming, has already begun encroaching on human settlements, especially on island nations, reducing their terrestrial real estate. Moreover, current average-global-temperature increases are undoubtedly contributing to droughts that are making farming more costly in large parts of the globe, including much of Florida, Arizona, the Plains states, and California. Climate change is also fostering more erratic weather, in many regions changing the onsets of monsoons and their intensities, both of which can also negatively affect farm cycles.
2) humans aren't the only animals of value. People share the globe with zillions of other species--from mighty oaks and algae to such charismatic megafauna as polar bears in the Arctic and penguins in the Antarctic. The latter are already losing their habitat as glaciers and polar ice sheets have begun melting at rates unheard of in recorded history. The greenhouse gases that human activities spew are certainly contributing to the warming cycle that threatens these polar zones with precipitous change, even as our own regions are slowly altering. And
3) recent warming trends have spurred the spread of disease-causing mosquitoes and other pests. No one would argue that fostering the spread of tropical and other diseases would be a global good.
Over the past few years--and especially the past few months--the august Intergovernmental Panel on Climate Change (IPCC) has issued reports representing the concensus of more than 1,000 of the world's best informed scientists on climate and its impacts. They conclude that human activities are driving up average global temperatures.
Indeed, just last month, IPCC issued a report to policymakers on the likely impacts of current climate trends. It concluded, contrary to many conservative pundits, that a synthesis of the accumulating data show dire impacts are likely to begin soon. Not only will corals, which play an integral role in ocean health, bleaching--a sign of stress and vulnerability to sickness, but wildfire risks are going to skyrocket. Sickness and death rates in human populations are predicted to soon rise due to those emerging diseases, inability to deal with heat waves or unusual flooding and droughts. Grain yields will suffer will fall at low latitudes but climb a bit at higher ones. Unfortunately, the soils at higher latitudes are often not suitable for grains.
Overall, it says to expect major disruptions to agriculture, falling freshwater supplies, and increased risk of sickness and death from communicable diseases.
Why is Griffin waffling on whether this is a long-term concern? Because some of the prediction may not happen?
Could it be politics? Can the fate of the globe afford to rest on politics instead of science?
This is truly food for thought...
Just what was NASA Administrator Michael Griffin trying to tell us in the National Public Radio interview, today, on Morning Edition?
"I'm aware that global warming exists," he flatly admits to NPR's Steve Inskeep. "I understand that the bulk of scientific evidence accumulated supports the claim that we've had about a 1-degree centigrade rise in temperature over the last century . . . I'm also aware of recent findings that appear to have . . . pretty well nailed down the conclusion that much of that is manmade."
Sounds like he's a believer in the message Al Gore has stumped for over the past 2 years (and eloquently articulated in what became the Academy Award winning film, An Inconvenient Truth).
However, where Gore and the science community have largely concluded global warming is bad for the planet, Griffin waffled on his assessment this morning, saying that "Whether [the current global warming trend] is a long-term concern or not, I can't say."
In fact, Griffin took a fairly strange tack in explaining his position to Inskeep, arguing that "To assume that it [global warming] is a problem is to assume that the state of Earth's climate today is the optimal climate, the best climate that we could have or ever have had . . . "
Interestingly, that's not the assumption I've made--nor have heard anyone else make.
Griffin goes on to charge that it's "a rather arrogant position" for people to accord themselves the right "of deciding that this particular climate that we have right here, today, right now, is the best climate for all other human beings."
The problems I find with that line of reasoning is that
1) no one has said today's climate is the best. Indeed, it probably should be a bit cooler than it is today if human habitability is going to be our yardstick. After all, sea-level rise, due to the current global warming, has already begun encroaching on human settlements, especially on island nations, reducing their terrestrial real estate. Moreover, current average-global-temperature increases are undoubtedly contributing to droughts that are making farming more costly in large parts of the globe, including much of Florida, Arizona, the Plains states, and California. Climate change is also fostering more erratic weather, in many regions changing the onsets of monsoons and their intensities, both of which can also negatively affect farm cycles.
2) humans aren't the only animals of value. People share the globe with zillions of other species--from mighty oaks and algae to such charismatic megafauna as polar bears in the Arctic and penguins in the Antarctic. The latter are already losing their habitat as glaciers and polar ice sheets have begun melting at rates unheard of in recorded history. The greenhouse gases that human activities spew are certainly contributing to the warming cycle that threatens these polar zones with precipitous change, even as our own regions are slowly altering. And
3) recent warming trends have spurred the spread of disease-causing mosquitoes and other pests. No one would argue that fostering the spread of tropical and other diseases would be a global good.
Over the past few years--and especially the past few months--the august Intergovernmental Panel on Climate Change (IPCC) has issued reports representing the concensus of more than 1,000 of the world's best informed scientists on climate and its impacts. They conclude that human activities are driving up average global temperatures.
Indeed, just last month, IPCC issued a report to policymakers on the likely impacts of current climate trends. It concluded, contrary to many conservative pundits, that a synthesis of the accumulating data show dire impacts are likely to begin soon. Not only will corals, which play an integral role in ocean health, bleaching--a sign of stress and vulnerability to sickness, but wildfire risks are going to skyrocket. Sickness and death rates in human populations are predicted to soon rise due to those emerging diseases, inability to deal with heat waves or unusual flooding and droughts. Grain yields will suffer will fall at low latitudes but climb a bit at higher ones. Unfortunately, the soils at higher latitudes are often not suitable for grains.
Overall, it says to expect major disruptions to agriculture, falling freshwater supplies, and increased risk of sickness and death from communicable diseases.
Why is Griffin waffling on whether this is a long-term concern? Because some of the prediction may not happen?
I'm betting Griffin buys life, fire, and homeowner's insurance. Why isn't he willing to acknowledge that the planet may need some insurance policies too?
Could it be politics? Can the fate of the globe afford to rest on politics instead of science?
This is truly food for thought...
Fish Stat
"Aquaculture is the fastest growing segment of world food production, accounting for 43% of seafood consumed globally. This $63 billion global industry will play a crucial role in coming years due to increased demand for seafood."
Source: May 30, 2007, Seafood Choices Newsletter, produced by SeaWeb. Available at: http://www.seafoodchoices.org/secure/newsletter-afishianado.php
Source: May 30, 2007, Seafood Choices Newsletter, produced by SeaWeb. Available at: http://www.seafoodchoices.org/secure/newsletter-afishianado.php
Wednesday, May 30, 2007
Cancerous Vacations?
The development of dark moles—known as melanocytic nevi—are the best predictor of whether an individual will eventually contract melanoma, the most deadly form of skin cancer. Sun exposure is the primary environmental cause of those melanocytic nevi. A new study now finds that among 2,189 German children between the ages of 6 and 7, nevi counts correlated best with a history of vacationing in a sunny locale with a high solar-ultraviolet-light index.
The higher the UV index, the higher the melanocytic nevi count, Olaf Gefeller of the University of Erlangen-Nuremberg, Germany, and his coworkers report in the May 15 American Journal of Epidemiology.
Where might one encounter a high UV index? At southerly locations, such as Mediterranean beaches. At high altitudes, such as alpine ski resorts. Or in even mid-latitude cities during the height of summer.
In contrast to many other studies, total sun exposure alone did not prove a good predictor of nevi risk. For instance, exposures at home didn't raise risks, not did vacation exposures at northern, sunny sites. The findings suggest, the researchers conclude, that "exposure to intense intermittent doses of UV radiation induced by frequent vacations early in life shows a strong association with [large mole] development."
In the past, history of severe childhood sunburns has proven a somewhat useful risk factor for malignant melanoma. However, teasing out the importance of other sun exposures has proven more difficult, the researchers note. The new study's large size and the children's common hometown made it fairly easy for the researchers to attribute differences in nevi development to difference in vacation sites.
The message these data really bring home is the importance of slathering a child with sunscreen if intense sun exposures—even relatively brief ones—are expected.
The higher the UV index, the higher the melanocytic nevi count, Olaf Gefeller of the University of Erlangen-Nuremberg, Germany, and his coworkers report in the May 15 American Journal of Epidemiology.
Where might one encounter a high UV index? At southerly locations, such as Mediterranean beaches. At high altitudes, such as alpine ski resorts. Or in even mid-latitude cities during the height of summer.
In contrast to many other studies, total sun exposure alone did not prove a good predictor of nevi risk. For instance, exposures at home didn't raise risks, not did vacation exposures at northern, sunny sites. The findings suggest, the researchers conclude, that "exposure to intense intermittent doses of UV radiation induced by frequent vacations early in life shows a strong association with [large mole] development."
In the past, history of severe childhood sunburns has proven a somewhat useful risk factor for malignant melanoma. However, teasing out the importance of other sun exposures has proven more difficult, the researchers note. The new study's large size and the children's common hometown made it fairly easy for the researchers to attribute differences in nevi development to difference in vacation sites.
The message these data really bring home is the importance of slathering a child with sunscreen if intense sun exposures—even relatively brief ones—are expected.
Sunday, May 27, 2007
Freetopia...Charitopia's Younger Sister
Google Freetopia and you'll get 2290 listings--at least as of today. This past week, the Stanford University team behind Charitopia launched a new sister website that will also be known as Freetopia.
Explains co-developer Michael Genesereth, the new site is "for people who wanted to offer goods to others for free. Just like eBay, but restricted to items offered for free."
Good luck finding it, however. As of today, the new website's URL (http://www.freetopia.org) will just direct you to the Stanford Logic Group, the computer scientists' general-research home page.
Explains co-developer Michael Genesereth, the new site is "for people who wanted to offer goods to others for free. Just like eBay, but restricted to items offered for free."
Good luck finding it, however. As of today, the new website's URL (http://www.freetopia.org) will just direct you to the Stanford Logic Group, the computer scientists' general-research home page.
More on Charitopia
A few days ago, I reported the unveiling of Charitopia, a website developed by Stanford University computer scientists that matches up donors of goods and charitable groups that could use those cast-offs. At the time I noted that details were sketchy. Well, Charitopia developer Michael Genesereth has since gotten back to me with some details.
As I suspected, the new program is currently operating only around the San Francisco Bay area, largely because arranging for the movement of "free" goods becomes problematic when the donor is in Chicago and the charity in Atlanta. However, he fully expects the program to eventually go international.
For now, Genesereth explains, "We try to match by zipcode. Getting goods transferred remains a problem even in this case. At any rate, it is the charity that is responsible for 'arranging' the exchange. In some cases, this means picking goods up. In some cases, it means asking donors to drop things off. We are also working with organizations like the UPS to do free pickup and delivery; however, we do not yet have any such deals signed. Finally, we are contemplating a volunteer service--to drive around on weekends to pick up and drop things off. Not yet in place either. This is a summer project for some students here."
Although Charitopia went live in March, as of last Friday, only 10 donors and charitable recipients had registered with the project's website (http://www.charitopia.org).
By the way, in just the last 4 days, that site has vastly expanded its utility. For instance, individuals no longer have to register and log in (which is, of course, free) to see what is available or what categories of goods it's currently soliciting.
Or, which charities have signed up. As of today, there are eight: AidsfreeAfrica; Belle Haven School; Budding Ballerinas; Charitopia; Freetopia; Gomoa Achiase School; Habitat for Humanity; and Stanford Logic Group.
However, things are moving along swiftly, Genesereth says. Later this week, he says, "We expect to have the system in full service, including email notifications of complementary listings and so forth."
Speaking of Freetopia, what's that? See the next post.
As I suspected, the new program is currently operating only around the San Francisco Bay area, largely because arranging for the movement of "free" goods becomes problematic when the donor is in Chicago and the charity in Atlanta. However, he fully expects the program to eventually go international.
For now, Genesereth explains, "We try to match by zipcode. Getting goods transferred remains a problem even in this case. At any rate, it is the charity that is responsible for 'arranging' the exchange. In some cases, this means picking goods up. In some cases, it means asking donors to drop things off. We are also working with organizations like the UPS to do free pickup and delivery; however, we do not yet have any such deals signed. Finally, we are contemplating a volunteer service--to drive around on weekends to pick up and drop things off. Not yet in place either. This is a summer project for some students here."
Although Charitopia went live in March, as of last Friday, only 10 donors and charitable recipients had registered with the project's website (http://www.charitopia.org).
By the way, in just the last 4 days, that site has vastly expanded its utility. For instance, individuals no longer have to register and log in (which is, of course, free) to see what is available or what categories of goods it's currently soliciting.
Or, which charities have signed up. As of today, there are eight: AidsfreeAfrica; Belle Haven School; Budding Ballerinas; Charitopia; Freetopia; Gomoa Achiase School; Habitat for Humanity; and Stanford Logic Group.
However, things are moving along swiftly, Genesereth says. Later this week, he says, "We expect to have the system in full service, including email notifications of complementary listings and so forth."
Speaking of Freetopia, what's that? See the next post.
Friday, May 25, 2007
Flame Retardant Gulls
Last evening, I cited research indicating that people may acquire much of their daily exposure to brominated flame retardants—ubiquitous and potentially toxic chemicals used to render many plastics, fabrics, and other materials resistant to burning—from the air in our homes. Well, today's post points out that wildlife also accumulate these chemicals, byproducts of humanity's love affair with plastics and foam-based goods.
The new paper, published Tuesday online—and slated to appear soon in a print edition of Environmental Science & Technology, reports Canadian research on fetal exposures to herring gulls (Larus argentatus) living around each of the Great Lakes. Not only did eggs of the birds contain anywhere from around 185 to 400 parts per billion (ppb) of polybrominated diphenyl ethers (PBDEs), but they also carried low-ppb concentrations of other types of brominated flame retardants as well.
Many of these are agents that manufacturers have been turning to now that two of the three major classes of PBDEs have been phased out in the United States and Europe. These replacements for PBDEs include chemicals with long, intimidating names, such as hexabromobenzene, pentabromoethylbenzene, and hexabromocyclododecane.
Lewis T. Gauthier of Environment Canada in Ottawa and his colleagues argue that since mother gulls are depositing these chemicals into their eggs, these newer non-PBDE flame retardants must taint the birds' freshwater prey.
What makes the findings potentially troubling: Almost no toxicity data exist for these non-PBDE flame retardants, despite the fact that they are starting to show up in measurable amounts in wildlife.
The new paper, published Tuesday online—and slated to appear soon in a print edition of Environmental Science & Technology, reports Canadian research on fetal exposures to herring gulls (Larus argentatus) living around each of the Great Lakes. Not only did eggs of the birds contain anywhere from around 185 to 400 parts per billion (ppb) of polybrominated diphenyl ethers (PBDEs), but they also carried low-ppb concentrations of other types of brominated flame retardants as well.
Many of these are agents that manufacturers have been turning to now that two of the three major classes of PBDEs have been phased out in the United States and Europe. These replacements for PBDEs include chemicals with long, intimidating names, such as hexabromobenzene, pentabromoethylbenzene, and hexabromocyclododecane.
Lewis T. Gauthier of Environment Canada in Ottawa and his colleagues argue that since mother gulls are depositing these chemicals into their eggs, these newer non-PBDE flame retardants must taint the birds' freshwater prey.
What makes the findings potentially troubling: Almost no toxicity data exist for these non-PBDE flame retardants, despite the fact that they are starting to show up in measurable amounts in wildlife.
Thursday, May 24, 2007
Flame Retardant Air?
A fairly ubiquitous class of flame retardants—chemicals used to keep products from readily burning—have been showing up in the environment, in animals, and in ourselves. Studies are just beginning to tease out the potential toxicity of one of the more prominent classes of these agents: They're PBDEs, an acronym which stands for a chemical mouthful—polybrominated diphenyl ethers. A new study now reports data suggesting that roughly one-fifth of the exposure of urban residents may come from the air in their homes.
Isn't that a pleasant thought.
Joseph G. Allen of the Boston University School of Public Health and his coworkers installed air-sampling devices in the bedrooms and main living rooms for each of 20 local volunteers. The devices ran for a week whenever the individuals were at home. The researchers also fitted each recruit with a personal air sampler that traveled with him or her around the home. Its intake was clipped to the recruits' shirt collars so that it would sniff the air at roughly nose level. At bedtime, the personal air sniffer was placed at bed height in the bedroom.
What's rather disturbing: The personal air sniffers picked up significantly more PBDEs than did devices just randomly sampling room air. For instance, the average concentration of these chemicals sniffed in the vicinity of the volunteers' heads was ~765 picograms per cubic meter in air—some 300 pg/m³ higher than in bedroom- or living-room air. The findings appear in a paper published online today and due to appear in print soon in Environmental Science & Technology.
The good news: Measured concentrations were low. However, these pollutants are remarkably persistent, meaning they don't readily degrade. So, there's a distinct possibility that exposures could accumulate, leading to a slow buildup of some of these compounds. What there is no question about is that these compounds do make it into our bodies in measurable quantities. Four years ago, university scientists in this country reported that human exposures begin in the womb and is augmented by breastmilk. That's troubling because studies have suggested that at least of few of these PBDEs can trigger subtle toxicity.
Presumably, the relatively high personal readings reflect individuals spending time in close proximity to household items treated with PBDEs. These might include sofas, mattresses, computer cases, electronics, or any of many other products. However, in this study, Allen's team was unable to correlate air readings with the presence of particular products in the tested homes.
Concern over the potential health effects of these agents led to a U.S. phase-out in the production and sale of two of the three common classes of them. The voluntary move by the manufacturers came after discussions with—and presumably more than a little pressure by—the Environmental Protection Agency. At the time, Europe had already instituted a ban on these chemicals. Together, these two classes comprise nearly 200 different PBDEs, although a few particular ones dominate each mix.
The third class, represented primarily by the deca-brominated PBDE, which is known as PBDE-209, remains in commercial use throughout the United States. In the new study, offgassing vapors of all three PBDE classes were detected in indoor air and by the personal-air sniffers (although concentrations of the deca-PBDE were second highest, on average, of the 12 individual PBDEs assayed).
What's the health significance of the new findings? No one knows. However, one recent study reported that fat cells exposed to brominated flame retardants undergo changes that would appear to foster obesity and type 2 diabetes. Another study showed that sunlight can break down some of these flame retardants into unusual members of the dioxin family. And European scientists, working with lab animals, linked PBDE exposures to reproductive and brain problems.
And what the new study reinforces is that our homes are not necessarily havens from these pollutants.
Isn't that a pleasant thought.
Joseph G. Allen of the Boston University School of Public Health and his coworkers installed air-sampling devices in the bedrooms and main living rooms for each of 20 local volunteers. The devices ran for a week whenever the individuals were at home. The researchers also fitted each recruit with a personal air sampler that traveled with him or her around the home. Its intake was clipped to the recruits' shirt collars so that it would sniff the air at roughly nose level. At bedtime, the personal air sniffer was placed at bed height in the bedroom.
What's rather disturbing: The personal air sniffers picked up significantly more PBDEs than did devices just randomly sampling room air. For instance, the average concentration of these chemicals sniffed in the vicinity of the volunteers' heads was ~765 picograms per cubic meter in air—some 300 pg/m³ higher than in bedroom- or living-room air. The findings appear in a paper published online today and due to appear in print soon in Environmental Science & Technology.
The good news: Measured concentrations were low. However, these pollutants are remarkably persistent, meaning they don't readily degrade. So, there's a distinct possibility that exposures could accumulate, leading to a slow buildup of some of these compounds. What there is no question about is that these compounds do make it into our bodies in measurable quantities. Four years ago, university scientists in this country reported that human exposures begin in the womb and is augmented by breastmilk. That's troubling because studies have suggested that at least of few of these PBDEs can trigger subtle toxicity.
Presumably, the relatively high personal readings reflect individuals spending time in close proximity to household items treated with PBDEs. These might include sofas, mattresses, computer cases, electronics, or any of many other products. However, in this study, Allen's team was unable to correlate air readings with the presence of particular products in the tested homes.
Concern over the potential health effects of these agents led to a U.S. phase-out in the production and sale of two of the three common classes of them. The voluntary move by the manufacturers came after discussions with—and presumably more than a little pressure by—the Environmental Protection Agency. At the time, Europe had already instituted a ban on these chemicals. Together, these two classes comprise nearly 200 different PBDEs, although a few particular ones dominate each mix.
The third class, represented primarily by the deca-brominated PBDE, which is known as PBDE-209, remains in commercial use throughout the United States. In the new study, offgassing vapors of all three PBDE classes were detected in indoor air and by the personal-air sniffers (although concentrations of the deca-PBDE were second highest, on average, of the 12 individual PBDEs assayed).
What's the health significance of the new findings? No one knows. However, one recent study reported that fat cells exposed to brominated flame retardants undergo changes that would appear to foster obesity and type 2 diabetes. Another study showed that sunlight can break down some of these flame retardants into unusual members of the dioxin family. And European scientists, working with lab animals, linked PBDE exposures to reproductive and brain problems.
And what the new study reinforces is that our homes are not necessarily havens from these pollutants.
Recycling Charitably
Charitopia. I guess what the Stanford University researchers had in mind when they named their website was some vision of a utopia for charitable giving. It's actually a site that matches up individuals having things to donate—from an unopened box of pencils to a car—with charities that can use them. There's no charge for the matchmaking service, either to donors or recipients. The site's developers also promise no advertising or spam.
A news release that went out to reporters, today, recommends the site for students finishing their school year and at wits end what to do with that chair, TV, and bookcase—items that worked well in the dorm but won't fit in the car to go home. Now, instead of pitching unwanted goods on the street, they can be matched up with hospitals, homeless shelters, or schools.
According to Michael Genesereth and Michael Kassoff, the scientists who designed the program, the site's matching abilities depend on the application of a branch of computer science that endows those number crunchers with reasoning skills. Both donors and would-be recipients identify what they have or want, based on descriptions of the goods in terms that both people and computers can understand. Then, the computer applies logical rules to pair up donors and charities. Donors can even select the type of charity they do or don't want to receive their items.
The project receives no outside funding beyond the Stanford computer-science department, and legal services for the site have been "secured" pro bono by Genesereth, who is research director of Stanford's Center for Computers and Law.
I tried contacting the Charitopia people earlier today to find out if their project has a national reach yet, or just works with parties in California. I've yet to hear back, and the website doesn't offer a clue.
Clearly, even though the site went live in March, the project is a work in progress. Today's news release notes that the Stanford team has hired a summer intern to manually update and increase the classifications for goods that can be listed with the site.
It certainly seems like a good idea. As the parent of a college student, I know how much stuff these young adults acquire over the course of 8 to 9 months—far more than our car can retrieve. Which is why I want to know: Is this service available in Pittsburgh yet?
A news release that went out to reporters, today, recommends the site for students finishing their school year and at wits end what to do with that chair, TV, and bookcase—items that worked well in the dorm but won't fit in the car to go home. Now, instead of pitching unwanted goods on the street, they can be matched up with hospitals, homeless shelters, or schools.
According to Michael Genesereth and Michael Kassoff, the scientists who designed the program, the site's matching abilities depend on the application of a branch of computer science that endows those number crunchers with reasoning skills. Both donors and would-be recipients identify what they have or want, based on descriptions of the goods in terms that both people and computers can understand. Then, the computer applies logical rules to pair up donors and charities. Donors can even select the type of charity they do or don't want to receive their items.
The project receives no outside funding beyond the Stanford computer-science department, and legal services for the site have been "secured" pro bono by Genesereth, who is research director of Stanford's Center for Computers and Law.
I tried contacting the Charitopia people earlier today to find out if their project has a national reach yet, or just works with parties in California. I've yet to hear back, and the website doesn't offer a clue.
Clearly, even though the site went live in March, the project is a work in progress. Today's news release notes that the Stanford team has hired a summer intern to manually update and increase the classifications for goods that can be listed with the site.
It certainly seems like a good idea. As the parent of a college student, I know how much stuff these young adults acquire over the course of 8 to 9 months—far more than our car can retrieve. Which is why I want to know: Is this service available in Pittsburgh yet?
Sunday, May 20, 2007
Endangered Species Stats
Mention endangered species, and most people think of pandas, black-footed ferrets, or whooping cranes. However, as of March 19, the largest number of endangered species in the Unied States were plants. In all, 598 of them, mostly flowering species, were formally listed as endangered, compared to just 412 animals.
Among animals, families with the most species endangered with extinction: birds with 76 , fish with 74, mammals with 69, and clams with 62.
Source: 2007. Endangered Species Bulletin, 2006 Highlights edition(May):56.
Among animals, families with the most species endangered with extinction: birds with 76 , fish with 74, mammals with 69, and clams with 62.
Source: 2007. Endangered Species Bulletin, 2006 Highlights edition(May):56.
Friday, May 18, 2007
West Nile Hammers Birds
Spread by mosquitoes, the West Nile virus has sickened more than 23,000 people in the United States since its introduction around 1999, killing more than 930 of them. Indeed, most news accounts of the disease's rapid spread have focused on West Nile's infection risk to people. However, birds have also proved highly vulnerable, as a new study indicates.
Walter D. Koenig of the University of California Berkeley and his colleagues charted changes in the breeding populations of birds throughout California between two counting seasons—the mid-1990s and the 2004-05 season. The latter period was selected because it is the first year that West Nile virus had been detected throughout the state.
The federally organized North American Breeding Bird Survey collects population data each year at the height of a species' breeding season. Such data were used for the new study only when the same person was responsible for bird counts in both periods, owing to large individual variations in counting techniques and reliability.
The scientists also pored over data on West Nile virus testing of 13,000 dead birds in the year leading up to the later breeding-bird census. The researchers restricted their estimates of West Nile's likely influence to just the breeding populations of the 29 passerines—perching birds or songbirds—for which virus prevalence information existed. Birds in this collection included the raven and crow, American goldfinch, song and house sparrows, barn swallow, robin, Western bluebird, and northern mockingbird.
In the just published March EcoHealth, the researchers report finding that species that had the highest virus prevalence rates, based on dead-bird testing, also experienced the greatest population declines between the two survey periods. The correlations proved especially strong for four species: the American crow, yellow-billed magpie, Western scrub jay and Steller's jay. When the researchers examined breeding-population data for these species in the 10 years leading up to the latest census, they saw no similar trend. In other words, it emerged only in the 2004-05 season, when the virus became widespread throughout California.
Other species also appeared to show some West Nile losses, but not to the same extent as these resident—nonmigratory—species. One bird that appeared fairly resistant to the virus: the raven.
Koenig's team concludes that West Nile infections have "had significant negative impacts on avian populations at a large geographic scale."
Walter D. Koenig of the University of California Berkeley and his colleagues charted changes in the breeding populations of birds throughout California between two counting seasons—the mid-1990s and the 2004-05 season. The latter period was selected because it is the first year that West Nile virus had been detected throughout the state.
The federally organized North American Breeding Bird Survey collects population data each year at the height of a species' breeding season. Such data were used for the new study only when the same person was responsible for bird counts in both periods, owing to large individual variations in counting techniques and reliability.
The scientists also pored over data on West Nile virus testing of 13,000 dead birds in the year leading up to the later breeding-bird census. The researchers restricted their estimates of West Nile's likely influence to just the breeding populations of the 29 passerines—perching birds or songbirds—for which virus prevalence information existed. Birds in this collection included the raven and crow, American goldfinch, song and house sparrows, barn swallow, robin, Western bluebird, and northern mockingbird.
In the just published March EcoHealth, the researchers report finding that species that had the highest virus prevalence rates, based on dead-bird testing, also experienced the greatest population declines between the two survey periods. The correlations proved especially strong for four species: the American crow, yellow-billed magpie, Western scrub jay and Steller's jay. When the researchers examined breeding-population data for these species in the 10 years leading up to the latest census, they saw no similar trend. In other words, it emerged only in the 2004-05 season, when the virus became widespread throughout California.
Other species also appeared to show some West Nile losses, but not to the same extent as these resident—nonmigratory—species. One bird that appeared fairly resistant to the virus: the raven.
Koenig's team concludes that West Nile infections have "had significant negative impacts on avian populations at a large geographic scale."
Whooping Cranes Redux
North America's tallest birds--whooping cranes (Grus americana)--are also among the rarest. The only remaining natural population of the endangered birds summers in Canada, then migrates some 2,400 miles to winter on the coast of Texas. The 237 whoopers that returned to their wintering grounds for the 2006-07 season were the largest number in a century, and 17 more than a year before, according to Tom Stehn and Wendy Brown of the U.S. Fish & Wildlife Service. Their report appears in that agency's just-published 2006 Highlights edition of the Endangered Species Bulletin.
In 1941, a mere 41 members of the species remained, largely due to habitat destruction, shooting, and other human activities. With the help of substantial federal protection in both Canada and the United States, the birds have been making a slow but steady rebound. The population grew to 100 by 1986 and reached 200 in 2004.
The species' 2006-07 winter tally reflects a record 49 chicks that reached fledging stage, last summer; all but four of these made it to Texas. In contrast, the year before, just 30 chicks arrived in the wintering grounds. Another record, the Bulletin notes: seven adult pairs made it to Texas with twin chicks in tow. Ordinarily, a female lays two eggs, only one of which survives through its first migration.
This past winter, five whooping cranes were also sighted at a New Mexico wildlife refuge, marking only the second time members of the species were seen wintering outside of Texas.
Nearly 5 feet tall, whoopers are majestic animals. Despite their growing numbers, the wild population's future remains anything but assured. The birds reproduce slowly and inhabit just a few nesting and wintering sites. As such, Stehn and Brown warn, "a single catastrophic event could eliminate the wild, self-sustaining . . . population." And we would all be the poorer for that.
In 1941, a mere 41 members of the species remained, largely due to habitat destruction, shooting, and other human activities. With the help of substantial federal protection in both Canada and the United States, the birds have been making a slow but steady rebound. The population grew to 100 by 1986 and reached 200 in 2004.
The species' 2006-07 winter tally reflects a record 49 chicks that reached fledging stage, last summer; all but four of these made it to Texas. In contrast, the year before, just 30 chicks arrived in the wintering grounds. Another record, the Bulletin notes: seven adult pairs made it to Texas with twin chicks in tow. Ordinarily, a female lays two eggs, only one of which survives through its first migration.
This past winter, five whooping cranes were also sighted at a New Mexico wildlife refuge, marking only the second time members of the species were seen wintering outside of Texas.
Nearly 5 feet tall, whoopers are majestic animals. Despite their growing numbers, the wild population's future remains anything but assured. The birds reproduce slowly and inhabit just a few nesting and wintering sites. As such, Stehn and Brown warn, "a single catastrophic event could eliminate the wild, self-sustaining . . . population." And we would all be the poorer for that.
Tuesday, May 8, 2007
Where You Recover From a Heart Attack Matters
It you're unfortunate to suffer a heart attack, pray it's in a city with clean air. That's the message from a pair of epidemiologists at the Harvard School of Public Health. How long you survive upon release from the hospital, and how well you recover, they find, can both be greatly affected by the amount of fine dustlike particles suspended in the air.
Antonella Zenobetti and Joel Schwartz collected Medicare data on 196,000 heart-attack survivors 65 and older who had been discharged from hospitals 1985 and 1999. They resided in 21 U.S. cities that ranged in size from Chicago to Youngstown, Ohio, and spanned the country from Honolulu to New Haven, Conn. The researchers then correlated long-term air-pollution data for each city--throughout the period following each individual's release from the hospital and for years afterward--with that individual's survival and any subsequent heart attacks or hospital admissions for congestive heart failure.
The scientists took into account factors that might affect survival--independent of any effect of pollution--such as age, type of heart attack suffered, the presence of diabetes or any of several other co-existing diseases, and time spent in the hospital during recovery.
In the May Environmental Health Perspectives, the authors note that theirs is the "first long-term study that investigated persons discharged alive following an acute myocardial infarction [heart attack]." The chief finding: survival was significantly diminished by coming home to breathe air polluted with substantial concentrations of particulates. They focused on values for particulates 10 micrometers in diameter or smaller, since these are the ones that are small enough to be inhaled deeply and to lodge in the lungs' tiniest airways--those that transfer oxygen to the bloodstream.
Antonella Zenobetti and Joel Schwartz collected Medicare data on 196,000 heart-attack survivors 65 and older who had been discharged from hospitals 1985 and 1999. They resided in 21 U.S. cities that ranged in size from Chicago to Youngstown, Ohio, and spanned the country from Honolulu to New Haven, Conn. The researchers then correlated long-term air-pollution data for each city--throughout the period following each individual's release from the hospital and for years afterward--with that individual's survival and any subsequent heart attacks or hospital admissions for congestive heart failure.
The scientists took into account factors that might affect survival--independent of any effect of pollution--such as age, type of heart attack suffered, the presence of diabetes or any of several other co-existing diseases, and time spent in the hospital during recovery.
In the May Environmental Health Perspectives, the authors note that theirs is the "first long-term study that investigated persons discharged alive following an acute myocardial infarction [heart attack]." The chief finding: survival was significantly diminished by coming home to breathe air polluted with substantial concentrations of particulates. They focused on values for particulates 10 micrometers in diameter or smaller, since these are the ones that are small enough to be inhaled deeply and to lodge in the lungs' tiniest airways--those that transfer oxygen to the bloodstream.
Monday, May 7, 2007
Toxic Baby Bibs
When you hear people talk about lead poisoning hazards, one of the first things that comes to mind is peeling paint chips in poorly maintained innercity apartments. Probably the last that would come to mind are vinyl-backed baby bibs. Which is what makes the story in last Friday's Chicago Daily Herald such a stunner.
Reporter Steve Zalusky interviewed a suburban grandma who apparently triggered a major investigation by the Center for Environmental Health, based in Oakland, Calif. Seems the grandmother had heard a news account about an investigation by that group, which had turned up lead in plastic lunch boxes. It caused her to wonder whether just any plastic might be contaminated.
So, she bought a test kit and used on her grandson's baby bib. When it tested positive for the toxic heavy metal, she bought more bibs and tested those as well. All came from a Chinese supplier for Wal-Mart, Zalusky says.
In a new report that the Center for Environmental Health released last week, Caroline Cox, its research director, noted that over the past 6 months, her group had purchased more than 50 brands of vinyl baby bibs and screened them. It then sent 18 that tested positive to an independent lab for further analysis.
The report said that vinyl portions of four "contained significant amounts of lead, above 600 parts per million." Cox explained that her group used that cutoff "because the Consumer Product Safety Commission classifies paints with more than 600 parts per million of lead as 'banned hazardous products.'” One subsequently tested bib from a Wal-Mart brand actually contained a whopping 9,700 parts per million lead.
On May 2, the Oakland Center announced that as a result of legal action it had taken, Wal-Mart will no longer sell the bibs, at least in California. When regulators in Illinois and New York learned of the problem, they negotiated with Wal-Mart for it to cease selling the bibs in their states as well.
However Cox's group found, Wal-Mart was not the only company selling lead-tainted bibs. A few other major companies distributed bibs that also tested positive. For now, the Center for Environmental Health recommends, worried parents should test any vinyl bibs their youngsters are using and substitute non-vinyl versions where lead is found.
The good news: At least this is an avoidable hazard. It's not like powdered lead wafting in open windows of buildings that lack air conditioning--something that Arlene Weiss, a consulting toxicologist with Environmental Medicine, in Westwood, N.J., documented last year.
I interviewed her at the Society of Toxicology meeting in San Diego. In the March 25, 2006 Science News, I note that the federal limit for lead in house dust is 40 micrograms per square foot of swabbed area. I then cited a study that Weiss and her colleagues had published 1 month earlier documenting that this lead limit "can be exceeded on [indoor] surfaces near windows in New York City after only 3 weeks of dust accumulation" from outdoor sources.
The choice there: Keep the windows tightly closed and swelter in the summer heat--or vacuum and damp-wipe all surfaces daily.
Reporter Steve Zalusky interviewed a suburban grandma who apparently triggered a major investigation by the Center for Environmental Health, based in Oakland, Calif. Seems the grandmother had heard a news account about an investigation by that group, which had turned up lead in plastic lunch boxes. It caused her to wonder whether just any plastic might be contaminated.
So, she bought a test kit and used on her grandson's baby bib. When it tested positive for the toxic heavy metal, she bought more bibs and tested those as well. All came from a Chinese supplier for Wal-Mart, Zalusky says.
In a new report that the Center for Environmental Health released last week, Caroline Cox, its research director, noted that over the past 6 months, her group had purchased more than 50 brands of vinyl baby bibs and screened them. It then sent 18 that tested positive to an independent lab for further analysis.
The report said that vinyl portions of four "contained significant amounts of lead, above 600 parts per million." Cox explained that her group used that cutoff "because the Consumer Product Safety Commission classifies paints with more than 600 parts per million of lead as 'banned hazardous products.'” One subsequently tested bib from a Wal-Mart brand actually contained a whopping 9,700 parts per million lead.
On May 2, the Oakland Center announced that as a result of legal action it had taken, Wal-Mart will no longer sell the bibs, at least in California. When regulators in Illinois and New York learned of the problem, they negotiated with Wal-Mart for it to cease selling the bibs in their states as well.
However Cox's group found, Wal-Mart was not the only company selling lead-tainted bibs. A few other major companies distributed bibs that also tested positive. For now, the Center for Environmental Health recommends, worried parents should test any vinyl bibs their youngsters are using and substitute non-vinyl versions where lead is found.
The good news: At least this is an avoidable hazard. It's not like powdered lead wafting in open windows of buildings that lack air conditioning--something that Arlene Weiss, a consulting toxicologist with Environmental Medicine, in Westwood, N.J., documented last year.
I interviewed her at the Society of Toxicology meeting in San Diego. In the March 25, 2006 Science News, I note that the federal limit for lead in house dust is 40 micrograms per square foot of swabbed area. I then cited a study that Weiss and her colleagues had published 1 month earlier documenting that this lead limit "can be exceeded on [indoor] surfaces near windows in New York City after only 3 weeks of dust accumulation" from outdoor sources.
The choice there: Keep the windows tightly closed and swelter in the summer heat--or vacuum and damp-wipe all surfaces daily.
Hormonal Fireworks?
Remember the old TV commercial: It's not nice to fool Mother Nature? Well that's what environmental hormones do--fool our bodies, or those of the critters around us, into taking biochemical directions from pollutants. Perchlorate is one such pollutant with a relatively recently recognized hormonal alter ego. A new report finds aquatic animals may encounter dramatic spikes in exposure to perchlorate following pyrotechnic displays.
Perchlorate is an ingredient of many rocket fuels, which is why Air Force bases can become perchlorate-rich environments. The compound also appears to help boost ceremonial rockets--firecrackers--into the sky. Unfortunately, our bodies mistake perchlorate for thyroid hormones. Ands because thyroid hormones play important roles in growth and neural development, exposure to this pollutant has the potential to do some pretty dastardly things.
For instance, I wrote a story for Science News, last August, that showed perchlorate masculinized certain female fish. So dramatic were the impacts that scientists initially mistook affected females for males. Several of these macho moms even displayed male-courtship behavior and produced sperm. Clearly, that was not something Mother Nature had intended. At a minimum, it could jeopardize reproduction in affected populations.
In the new study, researchers measured perchlorate concentrations in an Oklahoma lake over which fireworks were displayed. The scientists sampled the water before and for weeks after July 4 fireworks rained the rocket ingredient into the water. What they found is that concentrations peaked within a day of the pyrotechnic display, then disappeared. However, it could take almost 3 months for the pollutant to vanish.
To understand how it vanished, the scientists took some lake water back to the lab and added perchlorate to it. As long as the water housed its normal complement of aquatic microbes, the pollutant disappeared. It seems these bugs chow down on it--and how quickly they eliminate the perchlorate can depend on water temperature. However, when the researchers sterilized the water--killing its microbes--the perchlorate showed no signs of disappearing. The findings will appear in an upcoming issue of Environmental Science & Technology. Subscribers can see the article early online.
Although most concentrations in the new study were well below a part per billion, in one instance the peak maxxed out at 44 ppb. For perspective, the latter is within the range that perturbed the reproductive development of fish in the story I wrote last year.
I guess we'll just have to hope that our pyrotechnic displays don't coincide with pivotal developmental periods of nearby fish. Oops...aren't there places--like Disney World, for instance--where fireworks occur year-round?
Perchlorate is an ingredient of many rocket fuels, which is why Air Force bases can become perchlorate-rich environments. The compound also appears to help boost ceremonial rockets--firecrackers--into the sky. Unfortunately, our bodies mistake perchlorate for thyroid hormones. Ands because thyroid hormones play important roles in growth and neural development, exposure to this pollutant has the potential to do some pretty dastardly things.
For instance, I wrote a story for Science News, last August, that showed perchlorate masculinized certain female fish. So dramatic were the impacts that scientists initially mistook affected females for males. Several of these macho moms even displayed male-courtship behavior and produced sperm. Clearly, that was not something Mother Nature had intended. At a minimum, it could jeopardize reproduction in affected populations.
In the new study, researchers measured perchlorate concentrations in an Oklahoma lake over which fireworks were displayed. The scientists sampled the water before and for weeks after July 4 fireworks rained the rocket ingredient into the water. What they found is that concentrations peaked within a day of the pyrotechnic display, then disappeared. However, it could take almost 3 months for the pollutant to vanish.
To understand how it vanished, the scientists took some lake water back to the lab and added perchlorate to it. As long as the water housed its normal complement of aquatic microbes, the pollutant disappeared. It seems these bugs chow down on it--and how quickly they eliminate the perchlorate can depend on water temperature. However, when the researchers sterilized the water--killing its microbes--the perchlorate showed no signs of disappearing. The findings will appear in an upcoming issue of Environmental Science & Technology. Subscribers can see the article early online.
Although most concentrations in the new study were well below a part per billion, in one instance the peak maxxed out at 44 ppb. For perspective, the latter is within the range that perturbed the reproductive development of fish in the story I wrote last year.
I guess we'll just have to hope that our pyrotechnic displays don't coincide with pivotal developmental periods of nearby fish. Oops...aren't there places--like Disney World, for instance--where fireworks occur year-round?
Swimming in Hormones
Does the idea of drinking or swimming in hormones appeal? Probably not. However, a new report finds that hormones excreted by livestock not only end up in their manure, but also run off into the nation's waterways as rains wash through manure-treated fields.
So what? Hormones are terrifically powerful chemicals, agents designed to be biologically active in trace quantities. Their role: to orchestrate the body's every function, telling each tissue when it's time to turn genes on—or off. Let loose a signal at the wrong time and havoc can ensue. Which is why littering waterways can do a number on fish and other aquatic life.
In the new study, Jeanne Kjær of the Geological Survey of Denmark and Greenland and her colleagues measured concentrations of estrogens—female sex hormones—running off of fields that had been fertilized with pig manure. Levels of the hormones were in the low nanograms per liter—that's parts per trillion. Remember, though, these chemicals are designed to work at vanishingly tiny concentrations. Indeed, they often exert a stronger effect at low doses than at higher ones.
Measurable amounts of the sex hormones continued to leach off of fertilized fields for up to 3 months, the scientists will report in an upcoming issue of Environmental Science & Technology. Their article was published early online, last Saturday.
Feminization of male fish has been reported in many waters. I've covered those reports plenty myself in stories for Science News. Most of those reports pointed toward estrogens excreted by humans—and released into waters from sewage-treatment plants—as the likely source of any gender-bending effects witnessed in wildlife.
The new data imply that agriculture could be a substantial additional source of such contamination. Indeed, the authors argue, their findings "indicate an urgent need for further research into the risk of estrogen contamination of the aquatic environment" by manure-fertilized fields.
So what? Hormones are terrifically powerful chemicals, agents designed to be biologically active in trace quantities. Their role: to orchestrate the body's every function, telling each tissue when it's time to turn genes on—or off. Let loose a signal at the wrong time and havoc can ensue. Which is why littering waterways can do a number on fish and other aquatic life.
In the new study, Jeanne Kjær of the Geological Survey of Denmark and Greenland and her colleagues measured concentrations of estrogens—female sex hormones—running off of fields that had been fertilized with pig manure. Levels of the hormones were in the low nanograms per liter—that's parts per trillion. Remember, though, these chemicals are designed to work at vanishingly tiny concentrations. Indeed, they often exert a stronger effect at low doses than at higher ones.
Measurable amounts of the sex hormones continued to leach off of fertilized fields for up to 3 months, the scientists will report in an upcoming issue of Environmental Science & Technology. Their article was published early online, last Saturday.
Feminization of male fish has been reported in many waters. I've covered those reports plenty myself in stories for Science News. Most of those reports pointed toward estrogens excreted by humans—and released into waters from sewage-treatment plants—as the likely source of any gender-bending effects witnessed in wildlife.
The new data imply that agriculture could be a substantial additional source of such contamination. Indeed, the authors argue, their findings "indicate an urgent need for further research into the risk of estrogen contamination of the aquatic environment" by manure-fertilized fields.
Smoke and Wind
Pass by any major urban office building, these days, and you're likely to see at least a few souls commiserating outside the entrance about their forced eviction from smokefree offices whenever they feel an urge to light up. However, such nicotine addicts may find their lives constrained even more, if regulators get wind of new research published this month in the Journal of the Air & Waste Management Association.
Stanford University scientists wondered whether exiling smokers to the outdoor environment actually contributed substantially to pollution there. So, they set up continuous particle sensors to tally the tiny smoke particles in areas frequented by cigarette and cigar smokers--these were typically parks, outdoor cafes, sidewalks, and restaurant patios.
The bottom line: Sitting or standing downwind of a smoker could fill your breathing space with substantial amounts of smoke. How much? Within 1.5 feet of smokers, one could encounter upwards of 1,000 micrograms per cubic meter in air of fine particles. These are the type that can be inhaled deeply into lungs.
Admittedly, that was a maximum value. More typical ones were 200 to 500 micrograms per cubic meter of air. Still, Neil E. Klepeis and his colleagues report, concentrations at 1.5 feet downwind of an outdoor smoker were comparable to indoor concentrations found in smokers' homes. The big difference: Once an outdoor smoker puts out his or her cigarette, nearby air concentrations plummet to virtually zero. In homes, however, air isn't diluted as effectively as outdoors, so smoke remains aloft within rooms for hours after stubbing out a cigarette.
This is the first peer-reviewed data on systematic measurements of outdoor tobacco smoke. The study's authors conclude: "these data--that outdoor tobacco smoke levels can be substantial under certain conditions--[are] vital to the development of outdoor tobacco-control policy."
Of course, they're only telling us nonsmokers what we have been observing anecdotally: that outdoor air all too often fails to effectively dilute tobacco pollution. I'd say these data should begin discussions about whether even outdoor cafes need to consider offering us--especially patrons with small children--access to truly smokefree zones.
Stanford University scientists wondered whether exiling smokers to the outdoor environment actually contributed substantially to pollution there. So, they set up continuous particle sensors to tally the tiny smoke particles in areas frequented by cigarette and cigar smokers--these were typically parks, outdoor cafes, sidewalks, and restaurant patios.
The bottom line: Sitting or standing downwind of a smoker could fill your breathing space with substantial amounts of smoke. How much? Within 1.5 feet of smokers, one could encounter upwards of 1,000 micrograms per cubic meter in air of fine particles. These are the type that can be inhaled deeply into lungs.
Admittedly, that was a maximum value. More typical ones were 200 to 500 micrograms per cubic meter of air. Still, Neil E. Klepeis and his colleagues report, concentrations at 1.5 feet downwind of an outdoor smoker were comparable to indoor concentrations found in smokers' homes. The big difference: Once an outdoor smoker puts out his or her cigarette, nearby air concentrations plummet to virtually zero. In homes, however, air isn't diluted as effectively as outdoors, so smoke remains aloft within rooms for hours after stubbing out a cigarette.
This is the first peer-reviewed data on systematic measurements of outdoor tobacco smoke. The study's authors conclude: "these data--that outdoor tobacco smoke levels can be substantial under certain conditions--[are] vital to the development of outdoor tobacco-control policy."
Of course, they're only telling us nonsmokers what we have been observing anecdotally: that outdoor air all too often fails to effectively dilute tobacco pollution. I'd say these data should begin discussions about whether even outdoor cafes need to consider offering us--especially patrons with small children--access to truly smokefree zones.
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