Persistent organic pollutants POPs levels

There is growing evidence that environmental contaminants represent a conservation-level concern in some marine mammal populations, by contributing to an increased vulnerability to infection by natural or emergent pathogens. In this light, those marine mammals that are most contaminated with persistent organic pollutants (POPs) are most vulnerable to adverse health effects. Those species that occupy high trophic levels in aquatic food webs are typically the most contaminated [47 19],... 

The EMEP monitoring network of precipitation chemistry consists of about a hundred stations distributed in almost 30 countries across Europe.1 All of these measure inorganic ions as well as pH and conductivity. Figure 17.1 illustrates the concentration levels of sulfate (corrected for sea salt), nitrate, and ammonium in 2006. The monitoring sites of heavy metals and persistent organic pollutants (POPs) are less densely distributed 2 in 2006, there were around 50 for heavy metals such as lead... 

A number of potentially toxic metals have been reported in breast milk, including Cd, Hg, and Pb. Unlike the persistent organic pollutants (POPs), metals do not bind to the fat, and so they do not usually accumulate at concentrations higher in breast milk than in blood. As a result, infants are likely to be exposed to higher levels of toxic metals before birth than during breastfeeding. Nonetheless, knowledge of concentrations of potentially toxic metals in breast milk is important as an indication of both likely prenatal and postnatal exposure. 

Sandanger TM, Brustad M, Sandau CD, Lund E. Levels of persistent organic pollutants (POPs) in a coastal northern Norwegian population with high fish-liver intake. JEnviron Monit 2006 8(5) 552 7. 

Fig. 7.27 Bioaccumulation (a,c) and biomagnification (b,d) of persistent organic pollutants (POPs) with increasing trophic level (i.e. position occupied by a species in the food chain). Trophic level 2 animals are primary consumers (herbivores) while higher-level animals are carnivores.

O., Miyazaki, N., Petrov, E.A., Batoev, V.B. and Tanabe, S. (2006) Constitutive androstane receptor (CAR) as a potential sensing biomarker of persistent organic pollutants (POPs) in aquatic mammal molecular characterization, expression level, and ligand profiling in Baikal seal (Pusa sibirica). Toxicological Sciences, 94, 57-70. 

Persistent Organic Pollutants (POPs) and Persistent, Bioaccumulative and Toxic (PBT) substances are carbon-based chemicals that resist degradation in the environment and accumulate in the tissues of living organisms, where they can produce undesirable effects on human health or the environment at certain exposure levels (Pavan Worth, 2006). 

Although several authorities recommend not eating fish liver because of the risk associated with high intake of persistent organic pollutants (POPs), fish liver (and oil) is still consumed, it should be pointed out that PFC levels in liver are at least two orders of magnitude higher than that exists in the muscle tissue [90]. In Japan, concentrations of total PFC in skipjack tuna Uvers ranged from <1 to 83 ng/g wwt [91]. PFOS and PFUnA were the prominent compounds found. 

This chapter is focussed on the development at laboratory level of a new way of catalytic persistent organic pollutants (POPs) oxidation based on zeolites to reduce emissions and meet stringent environmental regulations. 

In terms of food quality, veterinary drugs are considered extraneous, contaminating substances whose presence is undesirable, although often inevitable. In this context, these substances are classified in the same group as environmental contaminants, such as mycotoxins, pesticides, polychlorinated biphenyls (PCBs) and other persistent organic pollutants (POPs). Like other types of contaminants, residues of veterinary drugs in foods present a potential health risk to the consumer. Therefore, the incidence and levels of veterinary drug residues in tissues have to be effectively and consistently controlled. 

This is one reason why indigenous Greenlanders are some of the most contaminated people on the planet. Moreover, some plasticizers such as those used in our PVC shower curtain, mentioned earlier are persistent organic pollutants (POPs), which are classified by their lack of discernible half-life, their ability to bioaccumulate, high levels of toxicity and the tendency to travel long distances. Over the next few thousand years, POPs will concentrate in the North, and many will stay there. This longevity also sets plasticizers apart from miasmas. 

How a chemical is distributed in the body affects the rapidity of its elimination. Chemicals that are distributed in body water are more immediately accessible to the bloodstream and hence are more available for elimination by the kidneys and the liver As their blood concentration falls as a result of elimination, water-soluble chemicals diffuse out of body water and back into the bloodstream. On the other hand, chemicals that are distributed in fat or bone tend to be less immediately accessible to the bloodstream, and the time required for their elimination tends to be longer. Indeed, fat and bone have the potential to act as internal somces of low-level exposme over time as the concentration of a chemical builds up in these tissues. Examples are lead, which tends to be sequestered in bone, and persistent organic pollutants (POPs) Uke dioxin and polychlorinated biphenyls (PCBs), which tend to be sequestered in fatty tissue. These and other chemicals may persist in the body for months or years. 

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