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Abstract.
Organohalogens are organic compounds that have at least one halogen atom and they are covalently bonded to carbon. Some of them have harmful impacts on human health and the environment. In some countries, the Stockholm Convention which is a global treaty aims to protect human health and the environment from persistent organic pollutants (P0Ps). Accumulated organohalogens bring a deterring health effect for instance in the Arctic fox. The predominant ones are polychlorinated biphenyls (PCBs) and chlordane (CHLs) (Pedersen et al.,2015). This paper examines environmental and health impact caused by organohalogens. Organohalogens can have both positive and negative effects, and their use and release to the environment should be carefully managed. However, on the negative side, some organic halogenated compounds have been found to persist in the environment, bioaccumulate in living organisms, and have a deterring health effecting the arctic Fox species.

Effects of organohalogens on the Arctic Fox.
Organohalogens are transferred into the arctic region via long range atmospheric and the sea current transports some into the region. Pedersen et al., (2015) suggest that lipophilic properties that are contained in persistent organic pollutants tend to biomagnify in the lipid storage of top arctic predators. They are the smallest homeothermic carnivores that remain active during cold weathers like winter (Pedersen et al., 2015). Arctic foxes are top predators in the arctic ecosystem and can be exposed to organohalogenated compounds through their diet mainly by consuming contaminated prey such as fish and birds. Although it is important to monitor anthropogenic pollutants, there is none to little local pollution in the arctic region (Pedersen et al., 2015). Sonne et al., (2008) concludes that fox fed contaminated whale blubber exhibited larger prevalence of renal lesions than foxes fed pork fat diet and the same for liver lesion. This can also have impact on the local population and top predators of the arctic regions. Arctic foxes exposed to organohalogens have a higher chance of developing liver and kidney lesion (Sonne et al., 2008).

when these compounds accumulate in the arctic foxes, they can lead to an increased mortality rate due to the toxic effects on their organs. Pedersen et al., (2015) indicate that Persistent organic pollutants (POPs) such as dichlorodiphenyltrichloroethane accumulate in the livers of the arctic foxes since the liver is considered one of the main targets of many contaminants. They can also cause reproduction and developmental issues. Organohalogenated contaminants can disrupt the hormonal balance of the arctic foxes, leading to reproductive and developmental issues. Due to this, they can alter hormone levels causing reduced fertility rate thus, affecting the development of the young Arctic fox species. Presence of polychlorinated biphenyls (PCBs) in the arctic fox have been associated with alterations in steroid hormone homeostasis to a larger extent than their parent compound (Pedersen et al., 2015). High levels of persistent organic pollutants at the end of the pupping period can cause high exposure levels in the fetus and the suckling pups.

Effect of organohalogens in the Baltic Sea.
The Baltic Sea is a brackish sea located in northern Europe. It is an inland sea with slow water exchange time with the Atlantic Ocean. de Wit et al., (2020) indicate that the sea has been facing several environmental challenges, including pollution from the surrounding countries with big populations. Many organohalogens are toxic to marine organisms including fish, shellfish, and plankton. These chemicals disrupt the normal physiological process of the organism, leading to reduced growth and reproduction. These affect the overall biodiversity and ecosystem health of the Baltic Sea. Excessive organic halogenated persistent organic pollutants (POPs) such as dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls contaminants in the 1970s and 1980s led to the decline of white-tailed eagles, grey seals, and the ringed seals in the Baltic Sea (de Wet et al., 2020 par. 1).

Reports show that Organochlorine in the Baltic Sea alters the sex hormone levels of different animals like seals, polar bears and whales. Organochlorine may affect thyroid hormone function and homeostasis in experimental animals like the grey seals (Sørmo et al., 2005). The study carried out indicates that grey seal pups from the Baltic Sea had lower plasma concentration compared to pups from the Norwegian waters of the open Atlantic Ocean (Sørmo et al., 2005). This is highly caused by feeding on contaminated fish from the Baltic Sea. The accumulation of these chemicals in their bloodstream disrupts their hormonal balances and how their body functions. Herring oil from the Baltic Sea can contain persistent organic pollutants (POPs). Oberg et al., (2002) shows studies that was carried out in which rats were exposed to high level of pollutants. Rats fed a herring oil diet showed the highest liver concentration of contaminants.

The Baltic Sea is known for its rich fisheries and seafood is an important source of food for the local population in that area. Oberg et al., (2002) suggest that the fish from the Baltic Sea is also used for commercial, sports and recreational activities by fishermen. The presence of organohalogens contaminates seafood and can pose risks to human health when consuming contaminated seafood. The sea is contaminated by chemical inputs which it receives via long-range atmospheric decomposition (de Wet et al., 2020). Another effect is that the presence of organohalogens has led to increased regulatory measures in the waters of the Baltic Sea, aimed at reducing their release into the environment. For example, the Stockholm Convention on persistent organic pollutants (POPs), which includes many organohalogens, has been established to regulate the use of this product (de Wet et al., 2020). As the production and use of PCBs have drastically reduced over the years leading to the recovery of many predators in the Baltic Sea, de Wet et al., (2020) explain that new chemicals such as new brominated, chlorinated flame retardant (FRs) and organophosphate ester-based compounds (OPEs) have come up.

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