Jonathan Patz is a climate change expert from the University of Wisconsin. His opinion on this topic highlights the importance of recognizing that climate change is about our health and changes impacts can impact our health in several ways. Some of those pathways are heat, vector-borne diseases, pollution, and more. The health risks due to climate change already damage marginalized groups like people with disabilities and low-income families, and climate change only seems to widen the gap. So it seems that climate change and health can be related.

Heat-aggravated illnesses

In 2016, a state report said they were expecting a considerable increase of premature deaths related to temperature rises during the summer in the United States. Some illnesses like heart and kidney problems can be exacerbated by extreme temperatures.

Heat is especially harmful to elders and kids, and even more for those with chronic medical conditions. Urban areas can also increase the probability of temperature rises due to the urban heat island effect. According to the EPA, air temperature in cities can be 22 degrees Fahrenheit warmer than in rural areas.

Respiratory illnesses

Warmer days increase ground-level ozone, mainly due to smog; the wildfires are more frequent, releasing dangerous particles and toxic gases into the atmosphere. Also, allergy seasons are worst every year.

According to an estimate by The World Health Organization, seven million deaths year worldwide occurred because of the air contamination. This organism also established that if we reduce burning fossil fuels, we could prevent two million premature deaths by 2050.

Vector-borne diseases

Michael A. Robert has studied dengue transmission in the U.S. in a warmer climate. According to Robert, if places are warmer, mosquitoes may live longer, and incubation time is shorter. As a result, the transmission is more likely to increase.

A 2016 study conducted by a Canadian laboratory established that warmer winters might extend the active season of sticks, which may result in an increase of tick-borne diseases. The researchers clarified that ticks are less likely to extend to other areas because they live longer and are less mobile than mosquitoes.

Food and water

Agriculture can be affected by climate change in many ways. Storms, droughts, and floods can destroy the crops. Corn is less likely to grow under high temperatures. The national department on agriculture says less milk is produced when the climate is too warm, and it is lower in protein, protein, and fat.

Rising sea levels and storms are a threat to water infrastructures. Patz’s research on Chicago’s stormwater drainage revealed that the probability of experiencing more overflows would rise from 50 to 120% by 2100.

Climatic catastrophes consequences

Hurricanes and wildfires consequences include death, injury, worsening medical conditions, and mental health.

In 2019, a study found that tropical storms increase the number of deaths by 52%. After weather catastrophes, people may develop psychological disorders like post-traumatic stress disorders, general anxiety, and depression.

Be prepared for tomorrow

All these problems can be prevented by taking action. Every step society takes for stopping global temperature from rising can save lives. Patz established that this is not a new issue; it’s one of the challenges health departments are already working on.

Climate Change is making its presence known with the impact that is happening when it comes to human and animal health. The Arctic has noticeably warmed up over the last decade and is not showing any signs of stopping. A recent study concluded that the temperature had seen a three times faster rise when it comes to the Arctic. This warming trend is seemingly not ending anytime soon and it can be noticed that the temperature can exceed predictions in the coming years.

This change is not just limited to the Arctic as the melted ice joins the sea; there is an increase in sea levels. The changes have reached us and the local community is taking the heat of the situation. Many observations have been made which has found some of the most profound changes in the local environment, especially the indigenous people of the Arctic. More than any part of the Northern Hemisphere, Arctic is one region which has taken the most damage in the recent years.

Direct Effects of Climate Change

One might not be very aware of the issue that climate change can have on the indigenous people. They have a unique connection with the nature around them. They are some people who have their whole lively hood set on the land, sea and natural resource that are available. The changes in the climate directly affect their well-being as there is an increase in events like storms, floods, extreme temperature crisis, etc.

 climate changes

 

Indirect Effects of Climate Change

With the changes that are occurring, the indigenous people are very vulnerable to increase stress causing mental and social health issues. Added to which is the increased risk of unpredictable storms which can cause a huge change in their everyday lifestyle. One of the risks that most people do not understand is that indigenous people are vulnerable to the risks of falling ill and with no proper medical support, they face mortality issues. With melting water, they have exposed themselves to bacterial and viral diseases, causing a decrease in their quality of life.

Other Health issues

With the changes in the climate, we can see a relationship which is being built when it comes to meeting different community. This has opened up a lot of different opportunities when it comes to food; this can be beneficial for some but puts them at a higher risk of obesity.

Artic

 

Artic is prone to a lot of endemic and epidemics which are spread from infectious diseases, which they are now well prepared to face. With the lack of availability of vaccines and increasing invasive diseases, the mortality rate does not seem to drop any time soon. But, we can say for sure that with climate change, people are not in safe hands even with the drugs that are produced in recent days. As these drugs are not well suited for their lifestyle and the extremities that they have lived their whole life in.

In the Arctic and Europe owing to climate-induced changes in contaminant cycling

ArcRisk is an international EU funded research activity that is looking at the linkages between environmental contaminants, climate change and human health – aimed at supporting European policy development in these areas. The Arctic setting provides unique opportunities for research in these fields.

All of us are exposed to environmental contaminants such as mercury and organic chemicals that persist in the environment. In some cases, exposure to these chemicals is high enough to raise concerns about possible subtle effects on human health.

Climate change has the potential to alter the pathways by which harmful chemicals cycle through the environment and enter food chains.

The Baltic Sea is located in the transition zone between continental and maritime climates and is one of the largest brackish waters in the world. It is recognized to be a sensitive and unique ecosystem which, like the Arctic, is vulnerable to climate change-induced effects.

Impact of climate change on POPs in the Arctic and the Baltic Sea region

In order to assess the climate change-induced effects, three IPCC climate change scenarios were adopted in the study, i.e., the A2, B2 and Baseline (BL) scenarios. The A2 and B2 climate scenarios represent high and low CO2 emissions, respectively, in the future, and the BL scenario represents the prevailing conditions, i.e., the current-day status of CO2 emissions. The POPCYCLING-Baltic model used in this study is a fugacity-based dynamic model for predicting the fate and transport of POPs in the Baltic region (Wania et al., 2000), see picture below.

Schematic presentation of the modelling study and the environmental compartments in the POPCYCLING-Baltic model (emission to water: 50 percent to fresh and coastal water, respectively; to soil: 50 percent to agricultural and forest soil, respectively).
The model was applied for an assessment of all hypothetical POPs with partitioning properties falling into −4 < log KAW < 11, 0 < log KOA < 15, and −2 < log KOW < 10. The model results suggest that the environmental levels of POPs in the Baltic Sea region are more sensitive to temperature than to particulate organic carbon (POC) and precipitation and least sensitive to wind speed. The model results furthermore suggests that the effects of individual parameters are not additive, as a cancelling effect can be noticed when all four parameters were assessed at the same time.

The results obtained with the use of the POPCYCLING Baltic model suggest:

Climate change can lead to changes (increases and/or decreases) in the environmental concentrations of POPs in the Baltic Sea region relative to the current baseline climate. The increasing factors can be up to 2.8, and the decreasing factors can be 1.8 under a more extreme IPCC climate scenario (A2).
Temperature is the most influential of the four climate-related parameters tested here.
Emission mode is important for accurately assessing the climate change-induced effects.
The results compare well with a recently conducted study focused on the Arctic region.
This approach assumes a steady-state emission of POPs and does not account for the anticipated decline in concentrations of many POPs in coming decades.

Comparison of modelled global climate change impacts in the Arctic and the Baltic Sea region

A comparison between model predictions for the Arctic and for the Baltic Sea was performed. Global climate change may intensify the volatilization of p,p’-DDT from both the Arctic and Baltic Sea waters. However, global climate change may play an additional role for the Arctic region by redistribute more p,p’-DDT to the Arctic region via either single- or multi-hopping effects (Semeena and Lammel, 2005).

All model results suggest increased atmospheric concentrations of POPs in the two regions. These increases (a factor of 1.8) are mainly due to intensified volatilization from surface compartments. The POPCYCLING-Baltic and DEHM (applied to the Arctic) models also predict decreased seawater concentrations of highly chlorinated PCBs, such as PCB-180 and PCB-194 in the two regions because of increased adsorption to POC and deposition to the sediment.
Model predictions suggest either an increase or a decrease in the atmospheric concentrations of three HCHs as a result of global climate change, depending on the model and its settings and chosen scenario. The factor of increase or decrease is up to 2.0. However, global climate change seems to play a similar role in the Arctic and in the Baltic Sea region with respect to the HCHs studied. In the Baltic Sea region, the long-term steady-state concentrations of the three HCHs in coastal and open-ocean water in the Baltic Sea are predicted always to decrease regardless of emission mode. In contrast, the atmospheric concentrations of the three HCHs will be increased due to climate change (except when β-HCH was emitted to air; in this case, its concentration was predicted to decrease in the Baltic atmosphere).

Results of the modelling suggested that changes in ocean circulation in the Arctic Ocean had caused changes in the surface seawater concentrations of PFOA. A recent study has suggested that atmospheric deposition together with riverine inflow could be major sources of PFOA and PFOS to the Baltic Sea region in comparison with the inputs from wastewater treatment plants. It has been hypothesized that this net input was due to the release of PFOA and PFOS previously retained in the soil and groundwater of the watershed (Filipovic et al., 2013). Based on that study, it could be hypothesized that climate change may lead to greater transport (from e.g. soil and ground water runoff in the catchment area) of PFOA and PFOS to the Baltic Sea.

Several field campaigns have been carried out as a part of the ArcRisk project. Data from these campaigns have been used for validation of models and to investigate transport processes, especially the link between abiotic and biotic environment. Transfer of POPs from abiotic matrices into biota is an important process, but there are few studies available. This page gives some of the ArcRisk results, and provides links to databases, not only from reviews conducted in the ArcRisk project, but also links to databases where large data sets and information are stored.

Databases of contaminants

Several field campaigns have been conducted in Arctic areas during the last decade. Within the ArcRisk project, an overview over POP levels has been established in 2010. It contains abiotic compartments such as air, snow, ice and water, as well as flux of contaminants within snowpacks and ice caps. In addition, low trophic level animals (plankton) have been included. Hence, this database provides an overview over recent data available. More studies are available, especially from the years after this overview was constructed.

An ISI ‘Web of Science’ and PubMed Literature survey (12.01.2012) revealed that about 1200 publications are available in peer-reviewed international journals on POPs in Arctic environments (since 1979). The ArcRisk project has compiled an overview of recent (1999-2011) and relevant reviews on fate and distribution of POPs and mercury in Arctic and Antarctic biota. The list can be downloaded here lænk till listan “relevant reviews on fate and distribution of POPs and mercury in Arctic and Antarctic biota” in D26. Information about analytical methods and sampling strategies are available in several peer reviewed articles.

Environment Canada provides regular reports on POPs levels in the North American Arctic as a part of the Northern Contaminants Program (NCP). These data are available on the internet – Canadian Arctic Contaminants Assessment Report. The written reports can be ordered directly from the NCP secretariat.

Environmental fate of organic contaminants

POPs can be transported from the primary source to remote areas. How far, when and how they will be transported is determined by their physical-chemical properties.

Changed temperatures and precipitation patterns can affect the abiotic transport processes as well as and their uptake in biota. Snow and ice melt brings “stored” POPs to the receiving rivers and oceans. Invading species might bring pollutants into the ecosystem, species composition might change in the ecosystems and the primary production can be affected as well. These are all examples of factors and processes that the ArcRisk project aimed to elucidate.

Fate processes in snowpack

In areas of high latitude (and altitude) snow is a significant source of atmospherically derived contaminants to catchment areas as well as marine waters (Blais et al., 2001; Daly and Wania, 2004; Bergknut et al., 2010; Pućko et al., 2011). However, the release of contaminants from the snowpack and their geochemistry following periods of thaw are not well understood, particularly for chemicals that are generally more polar, ionizable and/or largely non-volatile compared to semi-volatile “legacy” POPs. To date, there is a lack of measurement data for these chemicals in the remote snowpack.

Because snow accumulation on terrestrial surfaces or sea ice is controlled by several snowpack temperature- and wind-associated processes (e.g. wind pumping) that influence its structure and moisture content (Halsall, 2004; Herbert et al., 2006), chemical phase partitioning between vapour, particles, water and ice is crucial to understand the fate of contaminants in the snowpack. When melting commences with a seasonal increase in air temperature, chemical repartitioning can occur within the snowpack, which in turn will influence their elution order and release with meltwater (Halsall, 2004; Durnford and Dastoor, 2011; Meyer and Wania, 2010).

The geochemical behaviour of substances such as mercury and PFAS in the ageing snowpack is controlled by the physical properties of the snow and chemical processes (e.g., reduction and oxidation of Hg, and ice-based chemical partitioning coefficients for POPs), as well as particle type and amount. These interactions “decides” the fate of chemicals within the snowpack and control their elution during melt, either in a “first flush” (e.g., reactive gaseous mercury (RGM) and some shorter chain PFAs, such as perfluorobutane sulfonate (PFBS)), or later for particle-associated chemicals e.g. PHg). Despite the fact that PFAS are more water soluble than hydrophobic POPs, their various chain lengths and surfactant properties ensure a variable elution order during the onset of melt, although recent fieldwork conducted as part of the ArcRisk project shows that over time these chemicals will accumulate and undergo enrichment in snow layers prior to final melt.

Highest POPs concentrations in Arctic environments have been found in marine organisms due to bioaccumulation along the Arctic marine food webs. However, the transfer from the abiotic into the biotic compartment of the Arctic ecosystems depend on physical-chemical properties of the compound, the composition of the abiotic medium, as well as exchange processes with the organisms and surrounding environment (usually at low trophic levels).

Biologically available fractions of contaminants

The amount of POPs associated with the fraction of the abiotic medium transferred into an organism is considered as the bioavailable fraction for the specific abiotic medium investigated. Previous investigations have shown that the particulate composition in marine waters (distribution between dissolved and particulate phase) directly influences the partitioning of POPs. Temperature change has a direct influence on these processes and alters the partitioning of organic compounds between the dissolved and particulate phases in water and air. In addition, because many contaminants are strongly particle-associated, contaminated sediments can function as important secondary pollution sources for a long time after the primary sources have been stopped (Saloranta et al., 2011).

Within the framework of the ArcRisk project, food items, such as salmon, smoked halibut, whale and seal meat were purchased from the local market in Nuuk, Western Greenland, and examined for POP concentrations and distribution patterns. The concentrations for all pesticides were in the lower to medium (ng/g) range. The narwhal mattak (a local delicacy; blubber and skin from narwhal) samples showed the highest PCB and pesticide concentrations. These samples were analysed for chiral pesticides (α-HCH, trans- and cis-chlordane and the metabolite oxychlordane) as well. Chiral environmental pollutants are excellent indicators for the estimation of bioavailability and biotransformation potential in biological systems, even on an individual basis for top predator organisms (Kallenborn and Hühnerfuss, 2001; Wong and Bidleman, 2011). If the enantiomeric fraction (EF=EF1/(EF1+EF2) deviates from racemic distribution of enantiomers (EF=0.5), it is mainly caused by direct enantioselective biodegradation and/or accumulation. Enantioselective analytical methods can therefore help to estimate the bioavailability and biotransformation potential for chiral organic pollutants. The largest deviation from racemic distribution among the Greenlandic food items was found for all chiral compounds in narwhal. Many marine mammals (e.g., narwhal) have a notable metabolic capacity for biotransformation of POPs. Thus, potentially harmful transformation products are found in marine mammal tissues as a considerable contaminant contribution. These findings are considered as an indication of the above-average metabolic capacity of narwhals for biotransformation of the selected chiral organic pollutants.

Factors affecting bioavailability

Bioaccumulation factors (BAFs) determine the potential for accumulation of POPs in species. Factors presented within a suite of different studies are listed, see table below, for toxaphene, chlorinated benzenes, HCHs, DDTs, chlorobornanes, PCBs and PBDEs in plankton (Calanus spp) and beluga – ringed seal (PCB and PBDE). How much of a POP that is taken up in animals are determined by different factors, where the bioconcentration factor (BCF) is one of them. Bioconcentration factors means that POPs are up-concentrated from water to animals – like zooplankton at low trophic levels. The higher Kow (partitioning coefficient octanol-water), the higher BCF.

Human exposure to environmental pollutants occurs via the air, water and not the least, via the food we eat. How much pollutant one is exposed to depend on factors such as where we live and our habits. Seafood and fish from high up in the food web is an important exposure route for many contaminants.

If environmental pollutants will give negative effects and what those effects would depend on the exposure route and the properties of the pollutant. The potency of environmental pollutants differs widely and while one pollutant may give effect already at very low concentrations, others need to accumulate and maybe be transformed in the human body quite extensively before any effect may occur.

AMAP human health reports provide the baseline information on the health status of the populations living in the circumpolar area. Within the AMAP area, ten key areas have been identified that are a special focus for coordinated and harmonized monitoring and research activities. The main AMAP areas are: Chukotka Peninsula; the Mouth of Lena River; Taymir Peninsula, Norilsk area; Novaya Zemlya, Kara and Pechora Seas, the Mouth of Pechora River area; Kola Peninsula and Northern Fennoscandia area; Svalbard and East Greenland area; Baffin Island, West Greenland area; Canadian Arctic Islands and Arctic Archipelago; Lower Mackenzie River and Delta area; and Northern Alaska, North Slope area, see figure below.

A) The AMAP boundary of the Arctic (red line). The map shows ten key areas important to the AMAP monitoring program. B) Example of study sites from which data have been entered into the ArcRisk meta Database. The majority of the places are AMAP monitoring program sites (AMAP).
The work conducted within the ArcRisk project was focused on Europe and the European Arctic. Cohorts from the following areas in Europe were included in the ArcRisk: Croatia, Czech Republic, Finland, Greece, Greenland, Italy, Norway, Spain, Slovenia, and Russia. The areas were chosen to represent different climate zones, diets and exposure.

Scenario analyses of contamination in human populations due to environmental exposure and the fate of contamination are feasible only in areas where the population is monitored systematically for years. Within the AMAP area, human population contamination exposure has been monitored since 1992 with a varying number of follow-ups.

Effects of climate change on the food-web structure can have large consequences for the bioaccumulation of POPs. These can be bottom-up effects, in which changes in the abundance of primary producers influence the relative abundance of biota at higher trophic levels. They can also be top-down effects, where changes in the abundance of predators influence the relative abundance of organisms at lower trophic levels. Some top-down effects may be more evident, as changes in ice cover will have devastating effects on the abundance of top predators that depend on ice, such as polar bears and seals. Other top-down effects, such as predators switching to different prey and species moving to new regions, are more difficult to predict. Climate change effects on processes related to the intake of POPs could be enhanced intake in gills and intestines due to warmer temperatures and increased metabolism which may decrease internal concentrations or lead to increased exposure to toxic metabolites. Enforced fasting for e.g. polar bear may lead to increased residue levels.

Impacts on bioaccumulation modelling

There could be three primary mechanisms through which climate change can affect the bioaccumulation of environmental contaminants (Gouin et al., 2013):

climate change induced changes in environmental exposure (M1)
dietary exposure (M2) and
species-to-species uptake and loss rates (M3)
To date, only few modelling studies have investigated these mechanisms to some extent in the Arctic and Baltic Sea regions. In general, the physical environment played a relatively small role in determining the susceptibility to chemical exposure compared to the food web properties.

Hence, the global climate change induced direct changes (temperature and precipitation) would have little influence on the bioaccumulation of POPs in foods consumed by humans. Climate change induced effects were most likely to be indirect, such as changes in the dietary composition of food chains (M2). The direct effects on temperature-dependent uptake and loss rates are not likely to be significant compared to the indirect effects (M3).

Marine Food Web Modelling

A marine food web was chosen from the Svalbard region for initial model development. The Svalbard food web model contains plankton and fish samples taken within the ArcRisk project. A review of the marine ecosystem of Kongsfjorden in Svalbard by Hop et al. (2002) was utilized to help shape the initial structure of the Svalbard marine food web. The species included in the food web were algae, copepods (Calanus hyperboreus), amphipods (Onisimus spp., Apherusa glacialis and Themisto libellula), polar cod (Boreogadus saida), three seal species (Erignathus barbatus, Phoca hispida and P. groenlandica), and polar bears (Ursus maritimus). Levels of PCB in Svalbard waters in 2001 were used in the model (Sobek and Gustafsson, 2004).

Feeding relationships in the Svalbard marine food web (the linkage between developed food web and human cohorts of interest is missing in this food web; number means species specific trophic level).
The food web model underestimates the measured concentrations, which vary with the species and the PCB congener. PCB concentrations predicted in polar cod were most sensitive to the digestion factor, which suggests biomagnification as a very important factor. The herbivorous Apherusa glacialis are more affected by PCB concentrations in the water.

Humans living on Svalbard are relatively few in number (~2500), have a short residence time there and their diet does not include large contribution from local marine fish or mammals. Hence, studies of human exposure were done in other Arctic areas instead. The food web model from Svalbard is still highly relevant for human exposure in other Arctic areas, e.g. since the surrounding Barents Sea is important for the Norwegian and Russian fishing industry and the consumers. Bioaccumulation key processes are similar around the Arctic. Hence, results and tools developed within the Svalbard food web model can be applied on other Arctic food web systems that are more relevant for human exposure. However, even while using state-of-the-art modelling tools, the estimations of bioaccumulation in Arctic marine food webs under a changing climate is very difficult. Potential changes in the ecosystem, impact of invading species and ocean acidification are yet not fully understood.

Due to the slow uptake and elimination rates of many POPs at higher trophic levels (marine mammals), a dynamic model could provide improved predictions compared to a static model. A dynamic model is also expected to be more suitable compared to a steady-state model regarding PFAS, since the PFAS exposure changes rapidly over time.

To develop a relevant future climate change scenarios for food web modelling is challenging. A review by Cousins et al. (2011) demonstrated that predicting changes in food web structure due to future climate change is not yet possible. Information about possible scenarios and already on-going changes observed are needed before models can be further developed for food webs in change. ArcRisk have developed bioaccumulation models for Arctic food webs. However, data of POPs in sea water is still scarce, although needed to improve the models.

Environmental contaminants are emitted un-/intentionally. Pesticides are a classic example of intentional release of a toxic chemical to the environment. Other chemicals are released unintentionally to the environment e.g. by-products from industries. Furthermore, contamination from historical use may still be a source of emissions, e.g. via contaminated sediments and land.

The further fate of the contaminant depends both on properties of the substance and to which media the emissions took place. Some chemicals are long-lived as they persist degradation. Such chemicals can be transported long distances in air and water, accumulate in food webs and pollute areas and animals far from the original source.

Transport of POPs can be illustrated by “global fractionation”. They evaporate from the source – e.g. pesticides used in a southern agriculture. The pesticides are then transported with air further north (in the northern hemisphere), precipitate/scavenges out from the air. Eventually, the POPs repeat this process in several steps (“grasshopping”) until they reach the Arctic (Wania and Mackay 1996).

Emissions

Past, current and future emission patterns of contaminants

Emissions of legacy POPs such as DDTs, PCBs and HCHs have decreased during the last decades due to extensive regulatory action, including complete ban in several countries. Metal emissions, such as mercury, are also expected to decrease.

However, Pacyna et al. (2010) estimated an increase of Asian mercury emissions unless emission controls will be implemented. This is of high importance in a global perspective, since the emissions in Asia are estimated to be higher than any of the other continents. If emissions will continue to increase largely depend on economic development and advances in industrial techniques and emission control techniques. For the metals and unintentionally formed POPs, such as the dioxins, a complete ban is not possible as the contaminants are naturally occurring and unintentionally generated in processes not aiming to emit these contaminants.

Regional sources

As permafrost thaws in the Arctic, waste sites may leak contaminants to the receiving water systems. Less ice cover in Arctic facilitates shipping and off shore activities in a vulnerable area, where sea charts and search & rescue systems not always are well developed/within acceptable reach. These factors need to be taken into account for future work with contaminant risks in the Arctic, especially environmental pollutants related to transport, oil and gas. The North West and North East passage have already been used for shipping traffic. Shipping and offshore in the Arctic was one of the themes at the Arctic Frontiers 2014 conference in Tromsø, Norway.

Pathways and long-range transport of pollutants

POPs and mercury reach the Arctic mainly via atmospheric long range transport. Some substances are also transported via ocean currents and rivers.

DDT and PCB are examples of atmospheric transported compounds, while α-HCH can also be transported by water currents. Atmospheric transport of semivolatile POPs to the Arctic takes place via repeated evaporation and deposition events, resulting in the pollutant “hopping” to its final destination in the Arctic (Wania and Mackay 1996). Mercury is also transported from lower latitudes to the Arctic via the atmosphere. The transport mechanism involves different forms of mercury, both gaseous elemental mercury (Hg(0)), Hg(II) and particle bound species, and involve an oxidation process.

A number of contaminants are present the Arctic environment even though they have never been used or emitted there. The main pathway of persistent substances from source areas in e.g. Europe is via atmospheric transport and deposition. Another transport pathway of contaminants to Arctic is via the ocean currents.

Long-term monitoring of POPs in the air is conducted in Scandinavia and in Arctic and data from these measurements have been used in ArcRisk. Some of these data sets allow assessment of temporal trends of atmospheric concentrations. Environmental monitoring of concentrations of contaminants over time in different environmental matrices are a powerful tool to elucidate changes and trends of POP concentrations.

Measurements in the ArcRisk project have been conducted in e.g. snow and biotic samples. Environmental pollutants have different behaviour, or fate, depending on their properties. Some of them adsorb to soils and sediment, some are more water soluble than others. Environmental fate processes redistributes substance concentrations within the Arctic. POPs accumulate in lipids along the food web and can therefore be found in high levels in Arctic mammals. These behaviour characteristics are important when effects of climate change are assessed

Organic contaminants in the snowpack

Snow is a significant source of atmospherically derived contaminants of POPs to the terrestrial environment of the Arctic. However, there are relatively few studies of emerging substances such as PFAS and flame retardants. One study within the ArcRisk project investigated PFAS in the snowpack in northern Sweden and Norway.

Contribution of contaminants from freshwater to the marine environment
Inventories of PCBs in Arctic surface seawater of the pan-Arctic shelf seas estimated the amounts of PCBs to be in the order of 100 kg each. The PCB congener ‘fingerprint’ for each of the seven shelf seas and the interior basins, showed differences between the eastern (Pacific sector) and western (Atlantic) regions suggesting different source regions and/or transport pathways (Carrizo and Gustavsson, 2011).

An investigation (based on field observations ) of the PCB contribution from the six major rivers in the coastal Arctic seas showed that the river fluxes are likely a significant vector for delivery of PCBs to the Arctic Ocean (Carrizo and Gustavsson, 2011).

The fate of pesticides entering the ocean from melt water runoffs was assessed using passive- water and air samplers in Godthåbsfjord, Greenland (Carlsson et al., 2012). Chlordanes were found to have higher potential than more volatile contaminants (e.g. α-HCH and HCB) to act as tracers for melt water runoff into an Arctic fjord. Glaciers and meltwater from snow caps are potential sources of contaminants to the receiving fjords and lakes.

Organic contaminants in the marine environment

Main focus has been on the marine food web, since it represents the most common food source and main exposure route regarding POPs for humans around the Arctic. POPs in Greenlandic food items (raw/smoked salmon, smoked halibut, seal and whale beef, narwhal mattak) were analysed (Carlsson et al., 2013, 2014), and the concentrations were relatively low. PFAS was not detected in the fish samples, most likely due to industrial processing of the fish, e.g. washing and cleaning of the fillets. Narwhal mattak (the local delicacy of skin and blubber from the narwhal) contained highest concentrations of the pesticides, PCBs and PBDEs analysed, while seal beef contained highest concentrations of PFAS, see diagram below.

To assess selective transformation processes in these animals, enantiomeric selective analyses were performed for the chiral pesticides α-HCH, and trans-, cis- and oxychlordane. There was a difference between fish and mammals regarding α-HCH. This indicates that different uptake and/or transformation mechanisms were responsible for the non-racemic (un-even distribution of the enantiomers – the different types of the molecule) distributions in the analysed mammal and fish species. The seal samples were mostly racemic (even distribution of the enantiomers) for all pesticides, while the narwhal showed non-racemic enantiomeric fractions for all chiral pesticides analysed. There were no general enantiomer selective transformation/ accumulation trends found for chlordanes. This indicates that the enantiomer specific properties are an important prerequisite for the interaction of the chiral contaminant with internal metabolic processes.