Screening of New Chemicals in Sweden: The Siloxane Case

Transcription

1 Screening of New Chemicals in Sweden: The Siloxane Case Eva Brorström-Lundén, Lennart Kaj, Jeanette Andersson, Anna Palm Cousins, Mikael Remberger, IVL, Swedish Environmental Research Institute Martin Schlabach, Norbert Schmidbauer NILU, Norwegian Institute for Air Research

2 Screening of new chemicals in Sweden Main objective: to investigate the occurrence and concentration levels of selected chemicals in a variety of environmental media Limitation Measurements of a chemical in several media at several sites but only a few samples at each site Several screening studies, have been initiated and financed by the Swedish Environmental Protection Agency. The selection of substances is made by EPA Contact: Britta Hedlund

3 Screening of chemicals A way of dimensioning the problem Additional objectives Identification of possible emission pathways To highlight important transport pathways of the substance in the environment, e.g. atmospheric transport Investigate accumulation of the chemical in different parts of the ecosystem Investigate human exposure

4 Screening of chemicals Collection of background information Sampling strategi based on the properties of the substances, emissions and use and expected occurrence in the environment Measurements development of methods sampling chemical analyses Material flow analyses (MFA) Fugacity models Evaluation of the results

5 Screening 2004:The siloxane case Siloxanes, a large group of chemicals, used in a number of applications and it may be spread to the environment via diffusive emission from consumer products as well as via point sources Substances with molecular weights up to hundred thousands Fuel additives, Cleaning/washing agents, Impregnation materials, Surface treatment, Construction materials, Paints, Laquers, Reprographic agents, Process regulators, Cosmetics etc The Swedish screening study was performed in parallel with a coordinated screening in the Nordic countries which was financed by the Nordic Minister of Council.

6 Siloxanes included in the screening The screening was limited to substances with low molecular weights Octamethylcyclotetrasiloxane, D4 Decamethylcyclopentasiloxane,D5 Dodecamethylcyclohexasiloxane, D6 Hexamethyldisiloxane, MM or HMDS Si O Si O Si Octamethyltrisiloxane, MDM Decamethyltetrasiloxane, MD2M Dodecamethylpentasiloxane, MD3M

7 Siloxanes widely used chemicals D4, D5 and MM are chemicals of high production volume within EU D6 D5 D4 MM is included in the OSPAR list as a candidate for dangerous substances In Sweden, there is limited use of MD2M, MDM and MM, and more extensive use of D4, D5 and D6 Usage(tonnes) Year Swedish use of D4, D5 and D6 SPIN*, 2005 *SPIN Substances in preparation in the Nordic countries. The figures from the database only represent the registered use in chemical products

8 Siloxanes widely used chemicals 80 D4 D5 DK DK DK SE DK Total use (tonnes) SE NO SE FI NO SE FI NO NO SE FI Use of D4 and D5 in the different Nordic countries SPIN, 2005

9 Screening of siloxane A sampling strategy was designed in order to determine the concentrations of the selected siloxane Background areas Point source Diffusive sources Accumulation in the ecosystem Human exposure Air Water Sediment Municipal sludge Biota Breast milk

10 Analytical methods Air samples The samples were collected on adsorbent tubes, Tenax. The adsorbent tubes were analyzed using the thermal desorber and GC-MS Sludge, sediment, breast milk and water The samples were diluted with water and purged with a gas stream passing through an adsorbent Tenax and thermally desorbed and analysed by GC-MS purge and trap Biota (fish) samples A very short and comprehensive sample preparation was used. The sample was homogenised and mixed with 1 ml n-hexane and analysed on a GC-HRMS system Due to the ubiquity of the siloxanes great care was given to reduce the risk for contamination of the samples with siloxanes through direct contact with the lab staff, the equipment used for sample storage, preparation, and extraction.

11 Concentrations of siloxanes in air in Sweden Swedish west coast Industrial areas concentrations (ng/m 3 ) 100 background point source urban D4 D5 D6 MM Diffusive 0 Råö 1 Råö 2 Råö 3 Stenungsund 1 Stenungsund 2 Stenungsund 3 Stockvik 1 Stockvik 2 Stockvik 3 Stockholm 1 Stockholm 2 Stockholm 3

12 Concentrations of cyclic siloxanes (ng/g dw) in sediment from the Nordic countries D 4 D 5 D B a c k g ro u n d U rb a n /D iffu s e P o in t s o u rc e Concentration (ng/g dw) 5 0 DK Kattegat NO Bergsjøen NO Bergsjøen NO Røgden NO Røgden SE Gotlandsd. SE Landsortsd. DK Roskilde FO Kaldbakf. IS 1s IS 2s IS 3s IS 4s NO Leangbukta NO Vrengens. NO Möre SE Stockholm SE Stockholm DK Lynetten FI Helsinki FI Espoo SE Gislaved SE Gislaved SE Gislaved 0

13 Concentrations of cyclic (left) and linear (right) siloxanes in water (pg/l) N O O u t. O s lo fj. N O R ø g d e n N O B e rg s jø e n D K K a tte g a t N O In. O s lo fj. IS R e y k ja v ik IS R e y k ja v ik IS R e y k ja v ik IS R e y k ja v ik D K L y n e tte n re c D K R o s k ild e N O A re n d a l F I N o k ia 2 F I N o k ia 1 D K B je rg m a rk e n D K L y n e tte n N O A re n d a l F O S e rs ja n tv. F I N o k ia 2 F I N o k ia 1 F I H e ls in k i F I E s p o o D K B je rg m a rk e n D K L y n e tte n S E H ö g b y to rp 2 S E H ö g b y to rp 1 N O G rø n m o N O B ø ls ta d N O S p illh a u g IS A lfn e s F O H u s a rh a g a F I E s p o o D K U g g le lø s e D K A v e d ø re S E G is la v e d d o. S E G is la v e d e ff S E G is la v e d u p. D 4 D 5 D C o n c e n tra tio n (µ g /L ) B a c k g ro u n d U rb a n In c o m in g s e w a g e O u tg o in g s e w a g e L a n d fills O th e r p o in t s o u rc e C o n c e n tra tio n (µ g /L ) M M M D M M D 2 M M D 3 M Samples were collected in different water types in the Nordic countries Note the different scales on the x-axes

14 Concentrations of siloxanes in sludge from municipal STPs in Sweden (ng/g DW) Siloxanes were detected in all 52 samples M D 3 M M D 2 M M D M M M The lower and upper boundaries of the box represent the 25- and 75- percentiles, the line within the box is the median concentration. The whiskers represent the 10- and 90-percentiles, and the dots are individual results outside this range. D 6 D 5 D

15 Concentrations and distribution of cyclic siloxanes in marine fish liver collected in the Nordic countries Marine fish Concentration (ng/g ww) 50 D4 D5 D6 Background Urban/Diffuse DK North Sea DK Wadden Sea F FO Mylingsgr. FO Kaldbaksf. FO Kaldbaksf. NO Lista DK Roskilde DK Øresund NO Sørfjord NO Ulsteinvik NO Oslofjord 0

16 Human Exposure of siloxanes Concentrations of D4, D5 and D6 (µg/l) in breast milk Swedish screening µg/l 8 6 D6 D5 D The samples are sorted in decreasing order of concentration Sample were below the quantification limit The bars to the right illustrate the quantification limits.

17 Conclusions of the screening Siloxanes were frequently found in most of the analysed media but there were a great variation in concentrations The cyclic siloxanes occurred in significantly higher concentrations than the linear siloxanes and D5 was the dominating siloxane in most samples while D4 mostly was highest in air Diffuse sources seemed to be most important for the observed concentrations of siloxanes in Sweden and in the Nordic environment. The siloxanes was also detcted in biota

18 Conclusions The use of siloxanes is extensive and a continued use may lead to increased environmental levels. However the NOEC for D4 was only exceeded in one water sample, influent to STP Follow Morde data is needed to follow trends Studies of the human exposure Meaurements in sludge Measurements in food Evaluate the impotance of atmospheric transport

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