Pollutants in Brünnich’s guillemots

Method

Individual samples from Brünnich’s guillemot eggs are analysed.

The Brünnich’s guillemot is categorised as “near threatened” on the Norwegian Red List. Even though the Brünnich’s guillemot lays only one egg, it is not regarded as being harmful to the population to collect eggs for sampling purposes. If the egg is collected early in the season the bird can lay another in the same season. The eggs are collected in connection with other Norwegian Polar Institute fieldwork.

The samples are processed in the laboratory using a variety of techniques so that several groups of pollutants can be analysed.

The following is done to analyse for organic, fat-soluble chemical sprays, PCBs and some brominated flame retardants (BFRs):

• The content of the egg is homogenised in a mixer.
• Up to 4 grams of the homogenised ess is weighed and placed in a test tube and an internal standard is added for the substances to be analysed (PCB, BFR and herbicides).
• Fat and pollutants are extracted from the sample using cyclohexane and acetone, and the amount of fat is determined by weighing. Fat is removed from the sample using ultrapure, concentrated sulphuric acid.
• The sample now consists of solvent and pollutants. It is analysed in an interlinked, high-resolution, gas chromatograph (GC) and mass spectrometer (MS). The sample is injected into the GC and separated on a 30-metre column.
• The temperature programme for splitting starts at 60–70 °C and the temperature is raised according to pre-determined programmes depending on which substances are being analysed. Helium is used as the carrier gas in the machine.

The following is done to analyse for PFOS:

• The samples were extracted twice from homogenised eggs using acetonitrile in an ultrasound bath. Concentrated extracts were cleaned with charcoal and acetic acid. The clean extract was added to ammonium acetate and precipitated.
• High-performance liquid chromatography linked to high-resolution mass spectrometry (HPLC-HRMS) and double mass spectrometry (MS-MS) was used to analyse various fluorine-bearing substances. Internal standards, analysis of duplicates and reference material were used to quality assure the analysis.

The concentrations are calculated by quantifying internal standards with known concentration and comparing these with the response (chromatogram) from the samples.

Detection limits for the individual compounds are 3 times the noise level of the instrument. The median detection limit for PCB is 0.2ng/g wet weight. Median detection limits for DDT and DDE are 0.02ng/g wet weight. The variation in the detection limit for toxaphene was 0.2–0.7 ng/g wet weight. The median detection limit for chlordanes is 0.2ng/g wet weight. The median detection limit for HCB is 0.08ng/g wet weight. The median detection limit for HCB is 0.07ng/g wet weight. The uncertainty is around 25–30 %. The detection limit for brominated flame retardants is 0.01–0.17 ng/g wet weight. The median detection limit for PFOS is 50pg/g wet weight. The uncertainty is around 10–20 %.

Quality

The analysis is quality assured using the methods described in the accreditation. To avoid sample contamination, only superclean equipment is used in the laboratory. 2 blank samples and a standard reference sample are analysed for every 10th sample.

The laboratory is accredited for analyses of pollutants and regularly takes part in international proficiency testing schemes. The detection limit in particular, but also the measurement uncertainty, has improved in recent years. In time series, there will therefore always be greater uncertainty attached to older measurements in the series.

Since the data are only collected every 5th year, the analyses will fail to give information on the variation in the concentration of pollutants from year to year. When the time series is being analysed, allowance must therefore be made for the possibility that year-to-year variations are not being detected. It will therefore take a long time to prove changes in the time series because it is difficult to be certain that the difference between two measured points is due to an actual change or a random variation.

Other metadata

The Norwegian Polar Institute’s data service

Reference level and action level

Since POPs are manufactured pollutants that are not found in a natural state, the reference value for an unaffected state will be zero (really the detection limit).

Threshold limits

Since the Brünnich’s guillemot is a protected species, it is not used as human food. Hence, no limits related to human consumption have been set for the content of POPs in the Brünnich’s guillemot.

Stringent measures have been implemented to limit the spread of PCBs and other POPs. The Stockholm Convention regulates an international ban on their manufacture and use, and most western countries introduced strict regulations of PCBs around 1980. The Stockholm Convention regulates an international ban on the manufacture and use of DDT, and most western countries introduced strict regulations of DDT at the end of the 1960s and the beginning of the 1970s.

Measures have been applied to limit the spread of brominated flame retardants (BFRs). Norway has banned most BFRs and the Stockholm Convention included groups of BFRs in 2011 and the flame retardant HBCD in 2013.

Stringent measures have been applied to limit the spread of chlordanes. The Stockholm Convention regulates an international ban on the manufacture and use of chlordanes and most western countries introduced strict regulations of chlordanes in 1970–1990. Chlordanes have been little used in Europe. In May 2000, 3M, the world’s leading manufacturer of PFOS announced that it would voluntarily phase out PFOS and PFOS-related products because the substances had been shown to be present in the environment, including in the Arctic. Other types of PFAS are still being manufactured and widely used throughout the world. PFOS is banned in accordance with the Stockholm Convention, but this regulation has many exceptions. There is a proposal of adding PFOA to the Stockholm Convention and this is currently under consideration. 

Stringent measures have been implemented to limit the spread of HCB and HCH. The Stockholm Convention regulates an international ban on the manufacture and use of HCB as a fungicide and verifies that the chemical industry has reduced its emissions. The Stockholm Convention regulates an international ban on the manufacture and use of HCH. The use of lindane, which consists of an HCH mixture, was permitted in Norway until 1992. Around 2000, the use of technical HCH and lindane was forbidden in China and France, which were the main countries using the chemicals at the end of the 20th century.

Method

Individual samples from Brünnich’s guillemot eggs are analysed.

The Brünnich’s guillemot is categorised as Near Threatened on the Norwegian Red List. Even though the Brünnich’s guillemot lays only one egg, it is not considered harmful to the population to collect eggs for sampling. If the egg is collected early in the season the bird can lay another in the same season. The eggs are collected in connection with other Norwegian Polar Institute fieldwork.

The egg samples are digested in 5 ml of concentrated nitric acid. Following digestion, 1 ml concentrated hydrochloric acid is added and the mixture is diluted to 50.0 ml with water. The mercury is quantified using an Agilent 8800 ICP-MS-MS in oxygen reaction mode.

Quality

The laboratory is accredited for analyses of pollutants and regularly takes part in international proficiency testing schemes.

Standard reference materials and blank samples are analysed at the same time as the egg samples. This, together with the limit of detection and limit of quantification, form part of the quality control.

Since the data are only collected every 5th year, the analysis will fail to give information on the variation in the concentration of pollutants from year to year. When the time series is being analysed, allowance must therefore be made for the possibility that year-to-year variations are not being detected.

It will therefore take a long time to prove changes in the time series because it is difficult to be certain that the difference between two measured points is due to an actual change or a random variation.

Other metadata

The Norwegian Polar Institute’s data service

Reference level and action level

No limits have been set for metals in living organisms. Mercury is an element that is found naturally, but combustion of fossil fuels has caused the mercury levels to rise after the Industrial Revolution.

Threshold limits

As the Brünnich’s guillemot is a protected species, it is not used as human food. Hence, no limits have been set for the content of mercury or other pollutants in the Brünnich’s guillemot.

The heavy metals, cadmium, mercury and lead, are regulated through the Heavy Metal Protocol of 1998 (LRTAP Convention). Mercury emissions have been reduced in North America and Europe since the 1990s, but emissions in Asia have risen sharply.