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Case studies

Sweden: Stenungsund Bay

Stenungsund is a municipality at the Swedish west coast, about 40 km north of Gothenburg. It is host to the biggest chemical cluster in Sweden, centered around a steam cracker that produces ethylene and various fuel gases, which are then used by a range of companies for the production of polyethylene, polyvinyl chloride (PVC), amines, detergents, and various other chemicals. Additionally, there are several harbors situated along the coast.

Martin Hassellöv and Lena Gipperth are co-ordinators for this case study. The work in the first case study during 2017 focused on (i) evaluating the role of metals in the context of the complex chemical cocktails found in the area, (ii) analyzing the ecological consequences of chemical mixtures on natural invertebrate communities, (iii) developing algorithms for the prioritization of chemical mixtures for risk assessment in the context of the EU Water Framework Directive (WFD) and Marine Strategy Framework Directive (MSFD). Several of those datasets are currently under evaluation and will be submitted to peer-reviewed journals in 2018.

Chemicals emitted to Askeröfjorden

The first exposure modelling efforts focus on chemicals emitted to the aquatic compartment of Askeröfjorden from actives within the Stenungsund municipality.

Of the several identified chemical flows into Askeröfjorden it has been decided to start the modelling with the releases from consumers and consumer products. The main sources of chemical exposure and risk from consumers and consumer products are assumed to be pharmaceutical use, down the drain chemicals and textiles. Exposure and subsequent risk is for pharmaceuticals due to their inherent biological activity, down the drain chemicals due to the total amount used in society, and textiles due to the large total surface-area of textile products in Swedish homes. Chemicals are released from these sources directly into the aquatic environment due to excretion, intended use or washing.

A number of meetings and study visits (at e.g. the local sewage plant and local supervising authority) as well as gathering of material has been conducted during 2017. Next phase of the Stenungsund case study will include more deep analysis of legislation and decisions relating to the flow of chemicals in the study area.

The work with modelling emissions

Postdoc Mikael Gustavsson at Department of Mathematical Sciences is working on modelling the chemical emission from households into the aquatic environment: pharmaceuticals, textiles and down-the-drain chemicals.

He uses data from the National Board on Health and Welfare in Swedenof how much pharmaceuticals that is prescribed. He also uses data from SPIN, a database on the use of substances in products in the Nordic countries.

– You get different blocks that don’t fit, but you still have to try to stack them. We try to make fair estimations, says Mikael Gustavsson.

The goal is to be able to estimate how much one person in Sweden is causing when it comes to emission of chemicals per year, and how much water is needed to dilute it to a non-toxic level.Researchers in FRAM are also investigating the content of the  flows into and out from a waste water plant in Stenungsund. They will measure chemicals in the incoming waste water, and then again in the water being emitted from the waste water plant.

– Based on the available databases we can guess quite well what goes into the waste water plants, however the actual emissions at the end of pipe requires and additional modelling step, says Mikael Gustavsson.

If the citizens pay for a waste water treatment plant through taxes, there is a point in checking how efficient they are, he mentions. Which chemicals are being eliminated and which ones are not? The researchers in FRAM would like to model the input to the waste water treatment plant of about 5000 chemicals.

– It will be interesting to see how that corresponds to the monitoring that will be performed this summer. As we today have not designed the treatment-plants to specifically remove most of the chemicals we want to model, it will also be interesting to see how much of a reduction we sort of get for "free" with the currently implemented technology, says Mikael Gustavsson.

 

Chile: Aconcagua River

The Aconcagua River runs about 142 km through five Chilean provinces, supporting a number of cities along its way. The most important economic activities in the river basin are agriculture, mining and chemical production. Consequently, several studies have identified the pollution of the ecosystem with pesticide residues, heavy metals (especially mercury and chromium).

Pesticides are widely used in both developed and developing countries to control or destroy pests that interfere with the agricultural production and reduce the quality and yield of agricultural crops. The proper use of pesticides has certainly helped in increasing the yields of agricultural crops.

However, many countries lack regulations and enforcement to ensure that farmers properly handle and use pesticides. In addition, under existing international laws, highly toxic, banned or unregulated pesticides are being exported to developing and middle-income countries, posing a serious concern to human health and the environment. Such is the case of Chile, which is among the countries with the highest levels of pesticide use worldwide, with a total of 10.7 kg of agrochemicals per arable hectare as of 2009 compared to an average of 0.21 kilos by the other OECD members.

Linking status of ecosystem to chemical stressors

The FRAM case study will addresses knowledge gaps regarding the pesticide contamination and on the ecological status of surface waters in Chile. Although toxic effects on aquatic organisms are regularly observed, it remains a challenge to link the presence of chemicals with the ecological status of the aquatic ecosystem, to identify major chemical stressors, and to find strategies for the reduction of pesticide-related risks.

The River Aconcagua Basin is located in Central Chile and it drains an area of 7340 km2 where 690 km2 are used for agricultural activities. About 30% of both Chilean grape and peach production, as well as an important percentage of the avocado production is carried out in the River Aconcagua Basin. Based on the relevance of this river basin, FRAM aims to conduct a fieldwork where novel tools will be applied in the Chilean Case Study. A multi-disciplinary approach using cutting-edge techniques that combines the identification of complex chemical mixtures together with the assessment of their effects using DNA-based tools will be implemented.

Planning the research

Thomas Backhaus and Jessica Coria are co-ordinators for the second case study. The work in the Chilean case study during 2017 focused on (i) selecting and operationalizing the study area (the Aconcagua river basin was selected for this purpose, an area with high levels of agriculatural and mining activities), (ii) collecting the existing chemical and biological monitoring data from the Chilean authorities, (iii) establishing contacts in the environmental ministry and research community in Chile. The start of the experimental work is planned for autumn 2018.

The main body of information is only available in Spanish, but we’re fortunate in that Jessica Coria is Chilean and we have also recruited Spanish speaking natural science researchers within FRAM.

 

Kenya: Lake Naivasha

Lake Naivasha is the second largest freshwater lake in Kenya. It harbors a unique flora and fauna and has been declared a “wetland of international importance” under the Ramsar convention. Horticultural industry represents the main economic activity in the lake area, accompanied by tourism and fishing. As horticulture is quite laborintensive and therefore provides employment opportunities, the population of the town of Naivasha and the surrounding area lake hinterland has increased fifty-fold over the past three decades. As most settlements have only rudimentary waste treatment, and the shoreline is routinely used for laundry, the lake is not only polluted by pesticide residues and heavy metals, but also by a broad range of other organic pollutants. However, state-of-the-art chemical monitoring programs are completely absent.

Page Manager: Åsa Arrhenius|Last update: 6/12/2018
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