New seminar series

Lectures in Biogeochemistry and Atmospheric Science

This is an interdepartmental research seminar series. After a kick-start at end of this spring semester, its aim is to run approx. every second week from fall semester 2011. We look for a mix of external and internal presenters.

 

Please make suggestions to the organizers:

Patrick Crill IGV

Örjan Gustafsson ITM

Axel Horst ITM

 

Program as pdf

 

Chemicals in deodorants present in Baltic Sea fish and in Arctic air

Cyclic volatile methyl siloxanes (cVMS) are used as carriers in a range of personal care products such as deodorants and hair care products. Risk assessments performed in the EU and in Canada have indicated that some cVMS may be problematic environmental contaminants, in particular because there are indications that they are persistent in the environment, subject to long-range transport and accumulate in fish.

 

Predicted concentrations of D5 in the Northern hemisphere. The scale goes

from less than 0.1 ng/m3 (green) to more than 5 ng/m3 (red).

The aim of ITM's research was to explore these concerns, which are based largely on laboratory experiments, by studying the behaviour of cVMS in the environment. The key elements in the research to date have been:

• Creation of a method to measure trace levels of cVMS in the atmosphere. A novel method was developed and tested which for the first time allowed the reliable quantification of cVMS in ambient air at background levels.

• Assessment of the behaviour of cVMS in the atmosphere. D5, the cVMS chemical emitted in the largest quantities, was measured in air at a rural station in Sweden for 5 months. This provided the first data on the levels of these chemicals worldwide. A model of atmospheric circulation and chemistry was used to generate hemispheric scale predictions of D5 concentrations in the atmosphere (see video above), which were compared with the measurements. The results showed that the emissions and atmospheric degradation rate of D5 were consistent with existing estimates, and that D5 is clearly transported from the centres of emission (e.g. Western Europe) to remote areas such as the Arctic.

• Development of a method to measure trace levels of cVMS in fish. This second novel method allows cVMS to be quantified in fish from background regions.

• Analyse the occurrence of cVMS in fish in Sweden. High levels of cVMS were found in fish from lakes receiving sewage treatment plant (STP) effluent in Sweden, but levels were much lower in fish from remote lakes. This demonstrated the importance of STP emissions for the cVMS contamination of fish. Furthermore, cVMS were found in herring from around the Baltic Sea, which suggests that they are quite persistent in water.

• Evaluation of the bioaccumulation of cVMS in fish. Bioaccumulation (transfer to biota from the environment) was studied in fish from Swedish lakes and from the Humber River estuary in England. It was found that the transfer of D5 from these environments to fish was greater for D5 than for PCB153, a chemical that is known to be highly bioaccumulative.

 

Related publications

 

Determination of Cyclic Volatile Methylsiloxanes in Biota with a Purge and Trap Method

Kierkegaard, A.; Adolfsson-Erici, M.; McLachlan, M.S. 2010 | Analytical chemistry | 82 (9573-9578)

Determination of decamethylcyclopentasiloxane in air using commercial solid phase extraction cartridges

Kierkegaard, A.; McLachlan, M.S. 2010 | Journal of Chromatography A | 1217 (3557-3560)

 

Concentrations and Fate of Decamethylcyclopentasiloxane (D-5) in the Atmosphere

McLachlan, M.S.; Kierkegaard, A.; Hansen, KM; van Egmond, R; Christensen, JH; Skjoth, CA 2010 | Environmental science & technology | 44 (5365-5370)