Bionic plants

Deutsch: Animation einer Kohlenstoffnanoröhre

CAMBRIDGE, MA — Plants have many valuable functions: They provide food and fuel, release the oxygen that we breathe, and add beauty to our surroundings. Now, a team of MIT researchers wants to make plants even more useful by augmenting them with nanomaterials that could enhance their energy production and give them completely new functions, such as monitoring environmental pollutants. Continue reading “Bionic plants”

New study shows link between perfluorinated compounds and diabetes

Press release Published  2013-12-12

Perfluorinated  compounds are environmental toxins that are found in fire extinguishing foam and water-repellent textiles and, for example. In a new study, a research team led from Uppsala University has seen links between high levels of perfluorinated compounds in the blood and diabetes.

The research group at Uppsala University has previously shown associations between high levels of environmental toxins, such as PCB, pesticides, and phthalates and diabetes. In the new study they have investigated whether elevated levels of another type of environmental toxin, so-called perfluorinated compounds, are related to diabetes. Perfluorinated compounds are used in a wide variety of industrial and consumer products, including fire fighting foam, non-stick cookware, and grease and water-repellent materials such as food contact material, ski wax and GoreTex, for example. Continue reading “New study shows link between perfluorinated compounds and diabetes”

Perfluoroalkyl substances, PFASs, are crossing the blood brain barrier of polar bears/ Next up Humans

Contact: Robert Letcher robert.letcher@ec.gc.ca 01-161-329-13563 Aarhus University

Environmental toxins enter the brain tissue of polar bears

PerFluoroAlkyl Substances (PFASs) and precursor compounds have been used in a wide variety of commercial and industrial products over the past six decades. Applications include water and oil repellent coatings, e.g. for textiles, paper products, carpets and food packaging, pharmaceuticals and surfactants in cleaning products and fire-fighting foams. PFASs are highly resistant to chemical, thermal and biological degradation.

PFASs and their precursor compounds have shown a dramatic increase and dispersal around the world over the past four decades. An increasing amount of information is becoming available on the toxicity of these compounds. Hence, studies have documented the toxicity of PFASs on wildlife and human health, including carcinogenesis, genotoxicity and epigenetic effects as well as reproductive and developmental toxicities, neurotoxicity, effects on the endocrine system and immunotoxicity.

             IMAGE:   Different functional parts of the Greenland polar bear brain were investigated for transfer of contaminants over the blood-brain barrier. The inner regions of the brain closer to incoming blood flow…

Click here for more information.     

Bioaccumulative PFASs enter all parts of the brain

Despite the fact that the liver is considered the major repository in the body for most PFASs, some shorter chain compounds from this grouping have previously been reported in the brain of chicken embryos, suggesting that they are able to cross the blood–brain barrier.

Previous studies have shown a dramatic biomagnification  of several PFASs, and particularly one known as perfluorooctane sulfonate (PFOS) as well as several compounds of the perfluorinated carboxylate (PFCAs) grouping, in polar bears. PFOS have been shown to be at concentrations in the liver that are 100 fold higher than the ringed seals on which they are predating. In a new study Arctic researchers from Carleton University in Canada and Aarhus University in Denmark have used the polar bear as a sentinel species for humans and other predators in the top of the food chain. The researchers demonstrated accumulation of PFOS and several PFCAs in eight brain regions of polar bears collected from Scoresby Sound, East Greenland. Dr. Robert Letcher, Carleton University, explains:

“We know that fat soluble contaminants are able to cross the brain-blood barrier, but is it quite worrying that the PFOS and PFCAs, which are more associated with proteins in the body, were present in all the brain regions we analyzed.”

Professor Rune Dietz, Aarhus University, is also worried about the results:

“If PFOS and PFCAs can cross the blood-brain barrier in polar bears, it will also be the case in humans. The brain is one of the most essential parts of the body, where anthropogenic chemicals can have a severe impact. However, we are beginning to see the effect of the efforts to minimize the dispersal of this group of contaminants.”

Select environmentally labeled products

             IMAGE:   Perfluoroalkyl substances (PFASs) constitute a group of compounds where one end of the molecule consists of a carbon chain in which all the hydrogen atoms are replaced by fluorine atoms….

Click here for more information.     

The eight carbon chain PFOS and perfluorooctane carboxylate (PFOA) are PFASs have been phased out and are no longer produced in the western world. However, production in China, today the only known production source of PFOS and PFOA, has increased by roughly a factor of 10, since it was phased out in the USA. Unfortunately, no emission inventory is so far available from this region. Furthermore, replacements for PFOS and PFOA are now marketed and produced in e.g. the U.S.A. and China, which  generally have perfluorinated carbon chains that are shorter or branched.

Another recent study from Aarhus University documents that PFOS concentrations in Greenlandic polar bears and ringed seals started to decline after 2006. Other wildlife populations closer to the sources in Europe and North America have shown a decline prior to the Greenlandic animals. Rune Dietz comments:

“It is promising to see that the PFAS are on the decline. This development should be encouraged by the authorities globally.

In the meantime my best advice to the consumers is to go for environmentally labeled products. But avoiding products is difficult, because PFASs are so widespread in many kind of products and they are rarely declared.”

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FACTS

With fluorine in the tail

Perfluoroalkyl substances (PFASs) constitute a group of compounds where one end of the molecule consists of a carbon chain in which all the hydrogen atoms are replaced by fluorine atoms. This so-called perfluoroalkyl “tail” can be short or long, but the strong  C-F bonds make the tail more or less impossible to degrade, compared to the more well known  CFC-bonds. The best known PFAS is PFOS with an eight-chained perfluoroalkyl tail.

Further information:

Dr. Robert Letcher Carleton University Department of Chemistry tel.+011-613-998-6696 mobile: +011-613-291-3563 robert.letcher@ec.gc.ca

Professor DSc.Rune Dietz Aarhus University Department of Bioscience and Arctic Research Centre tel. +45-8715 8690 mobile: +45 21254035 rdi@dmu.dk

Literature:

Greaves, A.K., R.J. Letcher, C. Sonne, R. Dietz. 2013. Brain region distribution and patterns of bioaccumulative perfluoroalkyl carboxylic and sulfonic acids in highly exposed East Greenland polar bears (Ursus maritimus). Environ. Toxicol. Chem. 32:713-722. DOI: 10.1002/etc. 2107 http://www.ncbi.nlm.nih.gov/pubmed/23280712

Rigét, F., R. Bossi, C. Sonne, K. Vorkamp, R. Dietz (submitted). Trends of perfluorochemicals in Greenland ringed seals and polar bears: indications of shifts to decreasing trends. Chemosphere

Dioxins in Food Chain Linked to Breastfeeding Ills

2009 study posted for filing

Exposure to dioxins during pregnancy harms the cells in rapidly-changing breast tissue, which may explain why some women have trouble breastfeeding or don’t produce enough milk, according to a University of Rochester Medical Center study.

Researchers believe their findings, although only demonstrated in mice at this point, begin to address an area of health that impacts millions of women but has received little attention in the laboratory, said corresponding author B. Paige Lawrence, Ph.D., associate professor of Environmental Medicine and of Microbiology and Immunology at URMC.

“Estimates are that three to six million mothers worldwide are either unable to initiate breastfeeding or are unable to produce enough milk to nourish their infants,” Lawrence said. “But the cause of this problem is unclear, though it has been suggested that environmental contaminants might play a role. We showed definitively that a known and abundant pollutant has an adverse effect on the way mammary glands develop during pregnancy.”

Dioxins are generated mostly by the incineration of municipal and medical waste, especially certain plastics. Most people are exposed through diet. Dioxins get into the food supply when air emissions settle on farm fields and where livestock graze. Fish also ingest dioxins and related pollutants from contaminated waters. When humans take in dioxin – most often through meat, dairy products, fish and shellfish – the toxin settles in fatty tissues; natural elimination takes place very slowly. The typical human exposure is a daily low dose, which has been linked to possible impairment of the immune system and developing organs.

In 2004 Lawrence’s laboratory made the novel discovery that dioxin impairs the normal development of mammary glands during pregnancy. However, the underlying mechanisms were unclear, as was the extent of injury and whether exposure during certain stages of pregnancy had more or less of an impact on milk production.

This week, in an online report in Toxicological Sciences, researchers showed that dioxin has a profound effect on breast tissue by causing mammary cells to stop their natural cycle of proliferation as early as six days into pregnancy, and lasting through mid-pregnancy. In tissue samples from mice, exposure to dioxin caused a 50-percent decrease in new epithelial cells. This is important, Lawrence said, because mammary glands have a high rate of cell proliferation, especially during early to mid-pregnancy when the most rapid development of the mammary gland occurs.

Researchers also found that dioxin altered the induction of milk-producing genes, which occurs around the ninth day of pregnancy, and decreased the number of ductal branches and mature lobules in the mammary tissue.

The timing of dioxin exposure also seemed to be significant, the study noted. For example, when exposure occurs very early in pregnancy but not later, lab experiments showed that sometimes the mammary glands can partially recover from the cellular injury. However, although it is important to understand timing of exposure for research purposes, it is irrelevant for humans, who cannot really control their exposure to dioxins, Lawrence said.

“Our goal is not to find a safe window of exposure for humans, but to better understand how dioxins affect our health,” she said. “The best thing people who are concerned about this can do is think about what you eat and where your food comes from. We’re not suggesting that we all become vegans — but we hope this study raises awareness about how our food sources can increase the burden of pollutants in the body. Unfortunately, we have very little control over this, except perhaps through the legislative process.”

Much of Lawrence’s research focuses on a transcription factor known as aryl hydrocarbon receptor, or AhR.When pollutants enter the body they bind to AhR, which then turns on certain genes responsible for detoxification. By using dioxin to activate AhR, researchers have learned that dioxin impairs the ability to fight off infection. The link between dioxin and the immune system is still being studied, but meanwhile researchers looked further at the mammary tissue after observing coincidentally that cells involved in milk production were sustaining so much damage that rodents could not nourish their offspring.

The next step is to understand what controls the differentiation process. An important question to answer, Lawrence said, is whether the toxic harm is occurring directly in the breast, or if it occurs throughout the entire body but has a unique manifestation in the fatty mammary tissue.

The URMC research group is also studying a possible connection between dioxin and breast cancer.Their hypothesis is that dioxin exposure in some people might cancel the general protection that pregnancy has on breast tissue against breast cancer.

The research was supported by grants from the National Institutes of Health and the URMC Environmental Health Sciences Center, as well as the Art BeCAUSE Foundation of Boston, which funds breast-cancer related research.

WHEN in Rome, you get a little hit of cocaine with every breath.

  • 20 October 2012
  • Magazine issue 2887.

A study of psychotropic drug levels in ambient air from eight Italian cities found background levels of cocaine, cannabinoids – the active ingredients in marijuana – nicotine and caffeine in every urban centre.

Turin had the highest concentrations of cocaine, says Angelo Cecinato at the Institute of Atmospheric Pollution Research in Rome. Meanwhile, Bologna and Florence had some of the highest cannabinoid levels, which Cecinato attributes to the large student populations in the two cities. The drug concentrations are much too low to have an effect, though.

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Abstract

Psychotropic substances were monitored in eight big cities of Italy over one year, starting in May 2010, in the frame of the Ariadrugs Project. Yearly average concentrations ranged from 0.02 ± 0.01 to 0.26 ± 0.11 ng/m3 for cocaine, from 0.05 ± 0.05 to 0.96 ± 1.37 ng/m3 for cannabinoids, from 16 ± 6 to 61 ± 28 ng/m3 for nicotine, and from 1.0 ± 0.8 to 8 ± 7 ng/m3 for caffeine. Palermo and Turin were the cities suffering the lowest and the highest psychotropic substance concentrations, respectively. Nicotine and cocaine exhibited trends less seasonally modulated than common air toxicants. Caffeine and cannabinoids peaked in winter dropping close to zero from May to August. In Rome, where various anthropic contours were investigated in February 2011, differences were observed both in net concentrations and ratios of psychotropic substances vs. regulated toxicants. Ambient drugs look as a consequence of addiction and their burdens give insights about the corresponding consumes.

 

http://www.newscientist.com/article/mg21628874.600-drugs-in-the-italian-air-are-nothing-to-snort-at.html

http://www.sciencedirect.com/science/article/pii/S0269749112003612

 

 

Prenatal Damage from Dioxin Shown to Involve microRNAs

ScienceDaily (Sep. 17, 2012) — Research carried out at the University of South Carolina has identified novel mechanisms through which dioxin, a well-known environmental contaminant, can alter physiological functions, according to a study published online in the journal PLOS ONE.

The research team, which included Narendra Singh, Mitzi Nagarkatti and Prakash Nagarkatti of the USC School of Medicine, demonstrated that exposure to dioxin (TCDD) during pregnancy in an experimental mouse model can cause significant toxicity to the fetus, and specifically to the organs that produce the immune cells that fight infections. They found that dioxin alters small molecules called microRNAs, which can affect the expression of a large number of genes.

The study examined over 608 microRNAs, and 78 of these were significantly altered following exposure to dioxin. On the basis of the pattern of changes in these molecules, the team was also able to predict that dioxin can alter several genes that regulate cancer. Many other physiological systems were also affected, including those involved in reproductive, gastrointestinal, hematological, inflammation, renal and urological diseases as well as genetic, endocrine and developmental disorders.

Dioxin is a highly toxic chemical produced as a byproduct of industrial processes, such as the manufacture of herbicides or pesticides or the bleaching of paper. Because it degrades slowly in the environment and is soluble in fats, dioxin can bio-accumulate in the food chain and is often found in high concentrations in the milk and fat of animals in contaminated regions.

“Our results lend more credence to the hypothesis that fetal exposure to environmental contaminants can have life-long effects,” said Mitzi Nagarkatti. “Prenatal damage to the expression of microRNAs in the immune system could well impact the adult immune response.”

The research was supported in part by the National Institutes of Health (R01ES09098, P01AT003961, R01AT006888, R01ES019313, R01MH094755) and the Veterans Administration (VA Merit Award 1I01BX001357)

http://www.sciencedaily.com/releases/2012/09/120917124345.htm

Excess pneumonia deaths linked to engine exhaust

Repost File 2008

Contact: Rachael Davies
rdavies@bma.org.uk
44-020-738-36529
BMJ-British Medical Journal

Atmospheric pollutants and mortalities in English local authority areas

Engine exhaust fumes are linked to excess deaths from pneumonia across England, suggests research published in the Journal of Epidemiology and Community Health.

The annual death toll is comparable to that caused by the London smog in 1952, suggests the author.

Data on atmospheric emissions, published causes of death, and expected causes of death for 352 local authority jurisdictions in England were combined to calculate the impact of pollution on death rates between 1996 and 2004.

Levels of air pollution varied substantially among the local authorities.

Calculations revealed that pneumonia, peptic ulcer, coronary and rheumatic heart diseases, lung and stomach cancers, and other diseases, were all associated with a range of emissions, as well as deprivation, smoking, binge drinking and a northern location.

Further analysis, allowing for the effects of the social factors, showed that pneumonia deaths were strongly and independently linked to emissions, with the exception of sulphur dioxide from coal burning.

The primary culprits were emissions associated with oil combustion, including vehicle exhaust fumes.

During the eight years of the study there were almost 390.000 deaths from pneumonia.

And 35 local authorities accounted for almost 54,000 of these deaths, or around15,,000 more than would be expected.

“Total annual losses as a result of air pollution probably approach those of the 1952 London smog,” writes the author.

Because the links were so strong across all categories of exposure and deaths were so much higher than would be expected, this suggests that these pollutants directly damage lung tissue, he says.

Excess deaths from the progressive lung disease COPD (Chronic Obstructive Pulmonary Disease) and rheumatic heart disease, both of which are characterised by failing lung function, could also be precipitated by engine exhaust, he adds.