Team:HebrewU/Global aspects

HebrewU HujiGEM 2018

Although the formation of dioxins occurs "locally", environmental distribution is global. Dioxins are found throughout the world in small amounts, including areas that are entirely uninhabited. The highest levels of these compounds are found in some soils, sediments and food, especially dairy products, meat, fish and shellfish. Lower levels are found in plants, water and air.











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Regulation

Many countries monitor their food supply for dioxins. This has led to the early detection of dioxin contaminations and has often prevented its impact on a larger scale. Though nearly every country in the world contains some level of dioxin contamination, most cases have been reported in industrialized countries where adequate food-monitoring, greater public awareness [of the hazard] and better regulatory controls exist.



The Stockholm convention

In the 1990s, it became apparent that the international community needed to take action aimed at reducing persistent organic pollutants (POPs) to protect the environment and human health. This led to the formation of the Stockholm Convention on Persistent Organic Pollutants which was established on May 17, 2004. By 2005, over 150 countries had signed while 98 had ratified the Convention.

The objective of the Stockholm Convention is to protect human health and the environment from the effects of POP's. The convention established a range of measures to reduce and, where feasible, eliminate POP emissions, and to ensure the sound management of stockpiles and wastes that contain POPs. A level of 0.1 ng TEQ/m3 of dioxins has been accepted internationally as the goal emission rate.

Regulation in Israel

The Israeli Union for Environmental Defense is a non-profit organization that handles legal battles involved in environmental and health-related laws, regulation and governmental approvals In Israel. Through our correspondence with them, we have learned that Israel`s regulation is focused on limiting emissions, not production; meaning industrial facilities are allowed to produce as much dioxin as they wish but may not release them into the environment. This concerned us because a) there is no oversight of how much dioxin is produced, and b) the oversight of emissions seems to be very lax.

In a 2004 article, we found that there is a law that regulates the amount of dioxin production in factories, but there is little to no enforcement of said law. Could you shed light on whether there has been any progress in this matter in recent years?

"There is no regulation regarding the amount of production, but rather the amount of emissions [of dioxins]. The regulations have improved considerably since the Clean Air Law (2008) and went into effect (in 2011). Factories have limitations on dioxin emissions (as well as restrictions on other materials). Regarding enforcement, we think that there has been a slight improvement since 2004, although, to our understanding, the enforcement level it still quite lacking."

"An issue where no improvements have been made regards the current information on total dioxin emissions in Israel. Since the 2005 dioxin emission survey, there has been no further investigation or update, and today there is virtually no overall information on all the emissions of these pollutants in Israel."

In your 2014 report on the emissions of hazardous substances, it was mentioned that the State of Israel had signed the Stockholm Convention on Persistent Organic Pollutants treaty in 2001. The report states that, despite the signing, the state has not yet ratified it. What is needed for "ratification" to take place and has there been any progress on the issue since.

The signing of an international treaty is [unfortunately] more a declaration of intent, and its practical significance is relatively limited. While this particular ratification has a higher legal status than others - meaning that the state is placing the obligations it has undertaken through the Convention into Israeli legislation, making the obligations part of the binding law - there has been no change on this matter [since 2001].

Regulation in Estonia

Through collaboration with the Tartu University team, we were able to learn more about dioxin pollution in Estonia and the Baltic Sea. Estonian regulations are in line with those found in the EU. Though dioxin emissions in Estonia were lower than expected (when measured in 2003), there were still moderate pollution rates. It was estimated that large amount of pollutants comes with air masses from the Czech Republic, Germany and Poland . Dioxins enter the Baltic Sea as air fallout when transported from land-based sources which could be attributed to chemical and forest industries [especially in Russia where use of chlorine gas in these industries is still common practice].

Regulation in Australia

Australian regulation are also based on the limits that were accepted at the time of Stockholm convention (TEQ value below 0.1 ng). The Australian government announced a four-year National Dioxins Program back in 2001 to reduce dioxins and dioxin-like substances in the environment.

The studies [from Australia] show that the levels of dioxins in food, people and the environment are generally low when compared with levels internationally. They also showed that the risks to human health and the environment are low. Although there were only a small number of samples analyzed, these studies provided the largest survey of dioxin levels taken in Australia to date.

References:

1. "Dioxin and Furan Inventories. National and Regional Emissions of PCDD/PCDF" UNEP Chemicals, IOMC, Geneva, Switzerland (1999).
2. "Residues of persistent organic pollutants in Estonian soils" Kurunthachalam Senthil Kumara el al. (2008).
3. "Measurements of persistent organic pollutants in Estonian ambient air (1990–2013)" Ott Rootsa et al (2015).
4. "Summary report, Estonia - Work package 4: Identification of sources and estimation of inputs/impacts on the Baltic Sea" Mailis Laht, Estonian Environmental Research Centre Epp Volkov, Estonian Environmental Research Centre (2011).
5. "Dioxins in the Baltic Sea" Helsinki Commission Baltic Marine Environment Protection Commission (2004).
6. "National Dioxins Program in Australia,Department of Environment and Energy in Australia", Australian Government Website (2018).

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Global Aspects

Dioxins are mainly by-products of industrial processes, including waste incineration, but can also result from natural processes, such as volcanic eruptions and forest fires. Some of the processes that create Dioxins include smelting, chlorine bleaching of paper pulp and the manufacture of some herbicides and pesticides. When it comes to the release of dioxins into the environment, uncontrolled waste incinerators (solid waste and hospital waste) are often the worst culprits due to incomplete burning.

Dioxin-based waste is not easily disposed of without contaminating the environment and human populations. Such materials need to be treated as hazardous waste and are most quickly destroyed by high temperature incineration in specialized facilities.



Extensive stores of PCB-based [1] waste and industrial oils, many with high levels of PCDF's [2] exist throughout the world. The long-term storage and improper disposal of these materials may result in exposure and contamination of the environment as well as human and animal food supplies.

Quantitatively speaking, the annual global dioxin production is approx. 17,200 kg, which corresponds to about 287 kg-TEQ. TEQ stands for “Toxic Equivalent” which weighs the toxicity of the less toxic compounds as fractions of the toxicity of the most toxic dioxin - TCDD. It been previously calculated (2015) that the total annual emission rate of dioxins into the atmosphere, only 9 kg-TEQ (3%) remains in the air. For the rest, 57% is deposited to land areas (163 kg-TEQ), while the remaining 40% is absorbed by ocean waters (115 kg-TEQ or 354 kg/year).


[1] - Polychlorinated biphenyl, a molecule with a structure similar to dioxin.
[2] - Polychlorinated dibenzofuran, another molecule with structure similar to dioxin.

Main sources of dioxin in each continent:

Europe

The continent of Europe is one of the main producers of dioxins worldwide. The emissions are produced both from industrial activities and nonindustrial burning processes. The ambient concentration varies depending on the climate, residential activities, and the degree of development and social awareness of the inhabitants in the respective countries. Among them, heavily industrialized countries like Germany were the main producers of dioxins until a few years ago (1990s) when stricter legislation and the implementation of more efficient treatment mechanisms led to the decrease of emissions to minimal values. Other industrialized countries like Poland, where less strict legislation is applied, have not shown the same progression.

Asia

As by European countries, combustion activities, metal industries, and waste incineration are the main sources of dioxin emissions in Asia. Concentrations can differ depending on the dioxin-producing process, legislation for the area, and the social awareness of the population. Furthermore, China, as a singular country, has been identified as the largest dioxin emitter in the world. Annual dioxin emission in China from 10 source groups was up to 10.2 kg TEQ in 2004, accounting for about 30% of the total global emissions 14,15. Due to technical difficulties in dioxin monitoring and laboratory analysis, information on dioxin contaminations in food supplies (in China) is limited.

Africa

Dioxin contaminations in Africa are mostly not a result of processes that occur on the continent itself, but rather a result of the airborne travel of Dioxin emissions that originate from Europe, among other sources. Africa is one of the continents that are most influenced by this type of secondary contamination, altering the correlation between the ratio of dioxin accumulation and the ratio of dioxin production per country.

America:

TThe United States is the highest generator of dioxins in both North and South America. According to the study of the National Dioxin Air Monitoring Network (NDAMN), which measured the distribution of atmospheric pollution from 1999 to 2004 in the United States, higher ambient concentrations of airborne dioxins were found in the eastern part of the country.
Furthermore, based on analyses from 1987 to 2000 release of dioxin-like compounds from regulated industrial sources significantly dropped. he annual releases to the U.S. environment over the three reference years were:

14,000 g in 1987,
3,400 g in 1995,
1,400 g in 2000.

Antarctica, Oceania and the seas:

The lowest concentration levels are found in the Antarctic and Oceania, while Europe presents the highest concentrations in soils. On the other hand, the northern parts of the Pacific Ocean, the High Seas, and the Mediterranean Sea show the highest levels of dioxins in water.

Severe contamination events of dioxins:

Agent Orange and the American - Vietnam war

During the War between the US and Vietnam in the 1960’s, thousands of kilometers of land were heavily sprayed with an herbicide called Agent Orange, which was used to clear heavily forested areas. But TCDD was an unintended byproduct of Agent Orange production; thus, the military had unknowingly contaminated all of that land with this toxin. Even today, over 50 years after the event took place, the United States is spending hundreds of millions of dollars to reclaim that land.

Seveso disaster in Italy

An accident at a chemical factory in Seveso, Italy in 1976 resulted in the highest known exposure to TCDD in residential areas. A mixture of toxic chemicals, including TCDD, was released into the air, contaminating an area of about 15 km2 where over 37,000 people lived. Within days, over 3000 animals in the area, including livestock, had perished, with over 80,000 animals being put down in order to prevent the contamination from entering our food chain. In addition, nearly 500 residents received severe skin lesions. In studies on the long-term effects of exposure on the affected population, higher incidences of cancer, nerve damage, cardiovascular and respiratory diseases, and impaired liver function were observed. This event gave rise to numerous scientific studies and standardized industrial safety regulations in Europe.

References:

1. "Dioxins and their effects on human health" World Health Organization (2016).
2. "Review of the current state and main sources of dioxins around the world" Miguel Dopico & Alberto Gómez; Journal of the Air & Waste Management Association, 65:9, 1033-1049 (2015).
3. "Trend of cancer risk of Chinese inhabitants to dioxins due to changes in dietary patterns: 1980–2009" Tao Huang , Hong Gao & Jianmin Ma; Scientific Reports volume 6, Article number: 21997 (2016)
4. "National Dioxins Program in Australia", Department of Environment and Energy in Australia, Australian Government Website (2018).
5. "Inventory of Dioxin Sources and Environmental Releases" United States Environmental Protection Agency (2018).