Detecting toxic substances in polar bear brain tissue

(Danish and Canadian scientists have recently discovered that bioavailable perfluoroalkyl chemicals are overcoming the blood-brain barrier of polar bears from Scoresby Sound, East Greenland. .

PFASs chemicals and precursor compounds have been used in a wide range of commercial and industrial products over the past sixty years. Applications include water and oil repellent coatings, for example for textiles, paper products, carpets and food packaging, pharmaceuticals and inside surfaces of cleaning products and fire foams. PFASs are resistant to chemical decomposition, heat or biodegradation.

PFASs and precursor compounds of this chemical have been widely used all over the world with increasing amounts in the past forty years. More and more toxic properties of this compound are clarified. Therefore, this study recorded PFASs toxicity on human health and wildlife, including cancers, genetic toxicity and epigenetic effects and toxins. impact on the process of reproduction and development, impact on endocrine system and toxic immunity.

PFASs accumulate biologically into all parts of the brain. Although in fact, the liver is considered to be a major part of the body that holds most of PFASs, some of the shorter chain compounds of this group of chemicals have been found to be present in the brains of chicken embryos, this suggests. see they can cross the blood barrier - brain.

The Blood-Brain Barrier BBB is a biofilm. They have two basic functions: providing nutrients (biology) to feed brain cells and preventing substances harmful to brain cells.

Previous studies have demonstrated a marked biological amplification of some PFASs, and one of them is especially known as PFOS - perfluorooctane sulfonate as well as a group of PFCAs in polar bears. PFOS has been shown to accumulate in the liver at levels 100 times higher than Ringed seals. In a new study, Arctic researchers from Carleton University in Canada and Aarhus University in Denmark have used polar bears as a 'guard' species for humans and creatures. Eat other meat at the end of the food chain. Researchers have demonstrated the accumulation of PFOS and several PFCA chemicals in the No. 8 brain region of polar bears from the Scoresby Sound, East Greenland region. Dr. Robert Letcher, Carleton University, explains:

'We know that fat-soluble pollutants can cross the blood-brain barrier, but worrying because PFOS and PFCAs are more involved with body proteins, already present in all brain regions. that we have analyzed '.

Professor Rune Dietz from the University of Azerbaijan is also concerned about the consequences: 'If PFOS and PFCAs are able to cross the blood brain barrier in polar bears, it will also be similar to humans. The brain is the most important part of the body, where artificial chemicals can cause serious effects. However, we are beginning to see the effect of efforts to minimize the spread of these pollutant chemical groups. "

Select products with environmental labeling of 8 PFOS and perfluorooctane carboxylate (PFOA) chemicals that have been disposed of and are no longer produced in Western countries. However, made in China, which is now the only source of PFOS and PFOA, has increased almost tenfold, since these substances have been banned in the US. Unfortunately, so far there has been no emissions statistics from this area. Furthermore, chemicals that replace PFOS and PFOA are now commercial and manufactured, for example, in the US and China, these substitutes often have shorter or branched perfluorinated carbon chains.

Another recent study by the University of Aarhus calculated that PFOS concentrations in Greenland polar bears and ring seals began to decline after 2006. Other wildlife populations are close by. more with European and North American sources has shown a period of decline for Greenland animals.Dietune Rune commented: 'That is promising to see that PFAS is declining. This decline must be supported by global organizations'.

While our advice to customers is to use environmental labeled products. But rejecting products is very difficult, because PFAS is so popular in many products and they are rarely published.

Perfluoroalkyl substances (PFASs) are a group of compounds that one end has a carbon chain in which all hydrogen atoms are replaced by fluorine atoms. This so-called ' perfluoroalakyl ' tail may be short or long, but the strong bond between C - F makes it impossible to decompose much or less, compared to known CFC bonds. The most well-known PFAS is PFOS with a perfluoroalakyl 8-chain tail.