Not to be quoted without prior reference to the authors © Crown Copyright 2007

Fisheries Research Services Internal Report No 12/07

FRS METHOD FOR THE DETERMINATION OF TRACE METALS (INCLUDING RARE EARTH ELEMENTS) IN FRESHWATER SAMPLES BY INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY

Craig D Robinson, Sylvie Charles, Iain A Malcolm and Sandhya Devalla

May 2007

Fisheries Research Services Marine Laboratory Victoria Road Aberdeen. AB11 9DB

Fisheries Research Services Freshwater Laboratory Faskally Pitlochry. PH16 5LB

FRS Method for the Determination of Trace Metals in Freshwaters

FRS METHOD FOR THE DETERMINATION OF TRACE METALS (INCLUDING RARE EARTH ELEMENTS) IN FRESHWATER SAMPLES BY

INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY

Craig D. Robinson1, Sylvie Charles1, Ian A. Malcolm2, and Sandhya Devalla1

1Fisheries Research Services, Marine Laboratory

375 Victoria Road, Aberdeen, AB11 9DB 2Fisheries Research Services, Freshwater Laboratory

Faskally, Pitlochry, PH16 5LB

SUMMARY Fisheries Research Services require information on metals concentrations in freshwater (1) as part of long-term monitoring projects investigating the effects of environmental change (including reductions in atmospheric deposition of acidifying pollutants) (2) to assist in identification of source water provenance as part of hydrological and hydro-ecological studies. Trace element concentrations are currently determined by Inductively Coupled Plasma Mass Spectrometry (ICPMS). As part of the latter project identified above, there was a desire to expand the range of elements determined by ICP-MS to maximise the potential for identifying different source waters and to increase confidence in the existing measurements. For example, Fe showed low recovery (~75%) on its Quality Control chart in comparison to the certified value. For these reasons, a programme of method development and validation was conducted during 2006-07 which has resulted in successful expansion to the Scope of Accreditation (ISO17025) for the determination of trace elements (total 22), and additional validation of the determination of thorium and 14 Lanthanide elements in freshwaters. The utility of the method was demonstrated firstly by analysis of freshwater samples from the river Feshie during 2006, which assisted in source water determination, and secondly through analysis of samples collected from 38 sites in Galloway, SW Scotland. In the latter example, Environmental Quality Standards were exceeded for Mn at two sites, and for Cu at 8 sites.

INTRODUCTION For many years, Fisheries Research Services Freshwater Laboratory in Pitlochry (FRS FL) have monitored upland river water quality in relation to freshwater fisheries, changing land-use patterns (e.g. forestry), stream acidification and recovery (the Acid Waters Monitoring Network; AWMN), and environmental change. Such long-term datasets are important in understanding the effects of processes, such as changing atmospheric deposition and the growth of forestry plantations that occur over long timescales (FRS FL, 2006). This work complements the surface water monitoring undertaken by the Scottish Environment Protection Agency (SEPA), which is “predominantly designed to assess the impacts on water bodies from point sources” (SEPA, 2004). Recent FRS FL publications arising from these studies include Harriman et al. (2001, 2003) and McCartney et al. (2003). The analytes determined during FRS freshwater monitoring include pH, conductivity, alkalinity, nutrients (orthophosphate, nitrate, silicate), major anions (Cl-, SO4

2-), major cations (Ca2+, Na+, K+, NH4

+, Mg2+), monomeric aluminium and a number of trace metals (e.g. Fe, Mn, Cu, As, Al). FRS Marine Laboratory Aberdeen (FRS ML) is accredited to ISO17025 by UKAS for the determination of certain trace metals by Inductively Coupled Plasma Mass Spectrometry (ICP-MS); concentrations of the remaining analytes are determined using various UKAS accredited techniques undertaken at the FRS Freshwater Laboratory in

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FRS Method for the Determination of Trace Metals in Freshwaters Pitlochry. Other determinants measured at FRS FL, such as suspended solids and chlorophyll a are not currently accredited. FRS FL has also investigated how groundwaters can affect stream water quality, particularly with respect to salmonid spawning grounds (e.g. Malcolm et al., 2005). Recently this work resulted in the award of a NERC post-graduate studentship to the University of Aberdeen and FRS, the aim of which is to investigate the hydroecological significance of groundwater-surface water (GW-SW) interactions. One particular aspect of this project was to look at importance of GW-SW interactions on Atlantic salmon spawning site selection in the River Feshie, a tributary of the River Spey. The identification of sites within the stream catchment where groundwater contributions influence stream chemistry can be achieved using the differing elemental concentrations of groundwaters and surface waters as tracers (e.g. Soulsby et al., 2006). Previous scoping studies had identified the considerable potential of trace elements for identifying (1) groundwater contributions, and (2) the source of groundwater, based on the chemical signature of the local geology. Increasing the number of trace metals that can be included in the analysis, increases the potential utility of the method. FRS has a quality control policy that favours accreditation of analytical methods by the UK Accreditation Service (UKAS) to ISO17025. Consequently it was desirable that an extension to the existing UKAS Scope of Accreditation was sought to include additional metal determinants. The development and validation of these additional determinations, together with other recent methodological improvements made to the determination of trace metals in freshwater at FRS, are described. Objectives 1. To improve the determination of Fe.

Fe is determined as one of the usual suite of determinants, however its Quality Control (QC) chart indicated a relatively low recovery (75±3%) compared to the certified concentration of SLRS-4 Certified Reference Material (103±5 ppb). Participating in an interlaboratory proficiency testing scheme (organised by the Norwegian Institute for Water Research, NIVA) in 2002, 2004 and 2005, FRS obtained satisfactory results for four samples and unsatisfactory (low) results for two samples, with an indication of possibly reduced recoveries at lower concentrations (Fig. 1). Thus, there was a requirement to improve the determination of Fe in freshwater samples.

2. To obtain UKAS Accreditation for an expanded range of elements.

The existing analytes for whose determination in freshwaters FRS is currently UKAS Accredited are Al, Mn, Fe, Ni, Co, Cu, Zn, As, Cd, Hg, and Pb. A number of additional elements are included in the Multi-element Standard used for quantification purposes (Li, V, Cr, Se, Sr, Sn, Sb, Cs, Ba, Tl and U), and some of these are measurable in the SLRS-4 Certified Reference Material (CRM) that FRS uses for Quality Control of its freshwater metals analyses. To aid the groundwater-surface water project, it was decided to obtain additional accreditation for these elements.

3. To include the determination of Lanthanides and Th in the method.

To further aid the discrimination of the contribution of different water sources (ground and surface waters) to the overall water quality of the Girnock Burn, validation data was obtained for the determination of Lanthanides in freshwater samples.

4. To demonstrate the utility of the optimised method.

This was achieved by the determination of trace elemental concentrations in freshwater samples for (1) the determination of source waters in surface water samples in the River Feshie and (2) comparison with environmental quality standards using a selection of samples from the Galloway region.

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FRS Method for the Determination of Trace Metals in Freshwaters

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EXPERIMENTAL

Materials • Analytical (10 ppm Hg, Multi-element 2A, Rare Earth Elements; 1000 ppm Sn, Sb, Al,

Mn, Fe; 10,000 ppm Au) and internal standards (10 ppm Rh, 10 ppm Bi; 1000 ppm Sc, Ge) were of ICP-MS grade and purchased from SPEX CertiPrep Ltd. (Stanmore, Middlesex), or VWR International (Lutterworth, Leicestershire).

• Standards used for preparing spiked materials (1000 ppm Li, Se, Sb, Cs, Sn, Tl, Hg)

were purchased from VWR International (Lutterworth, Leicestershire) or SCP Science (Courtaboeuf, France).

• Concentrated nitric acid (Aristar grade, s.g. = 1.45) was purchased from VWR

International (Lutterworth, Leicestershire). • Ammonia and argon (>99.999%) gases were purchased from BOC (Aberdeen, UK). • Ultrapure deionised water (18.2 MΩ.cm) was prepared using an Elga Purelab UHQII

water system (Elga, Marlowe, Buckinghamshire). • SLRS-4 Certified Reference Material is prepared by National Research Council

Canada and was purchased from LGC Promochem, Middlesex, UK. • 1% v/v nitric acid solution (used in the preparation of standards, spiked solutions and

diluted internal standard mix) was prepared in aged polypropylene bottles by the addition of 20 ml Aristar conc. nitric acid to 1980 ml ultrapure deionised water.

• Internal standards mixture is prepared by diluting the stock standard solutions in 1%

nitric acid to a final concentration of 1 ppm Rh, 10 ppm Sc, 20 ppm Ge, 500 ppm Au, 1 ppm Bi.

Equipment Samples and standards were prepared in a horizontal laminar flow Class 100 clean air cabinet (MDH Ltd., Andover, Hants.), using calibrated Rainin EDP 1-10 ml electronic pipettes, Gilson or Soccorex manual pipettes (1-20; 10-200; 100-1000 µl), and disposable polypropylene centrifuge tubes (Fisher Scientific Ltd., Loughborough, Leicestershire). Elemental determinations were made using a Perkin-Elmer Sciex Elan 6100DRC Inductively Coupled Plasma Mass Spectrometer (ICP-MS) fitted with a Scott double pass spray chamber, cross-flow nebuliser, Gilson 312 peristaltic pump and Perkin-Elmer AS-91 autosampler (Perkin Elmer, Seer Green, Buckinghamshire). The instrument can be operated in standard mode, or by using the Dynamic Reaction Cell (DRC; ICP-DRC-MS). Sample Preparation Freshwater samples (25 ml) were received at FRS ML from FRS FL acidified to 1% v/v with cHNO3. The samples were centrifuged to remove any suspended solids, and 100 µl of the mixed internal standard solution added to 9.9 ml of sample prior to analysis.

FRS Method for the Determination of Trace Metals in Freshwaters

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Experimental Approach 1. To improve the determination of Fe.

Fe has four isotopes, 54, 56, 57 and 58, with natural abundances of 5.8, 91.72, 2.2 and 0.28% respectively. Using ICP-MS for elemental determinations, each of these isotopes suffers from significant interferences due to the formation of polyatomic species within the plasma, for example ArN at m/z 54, ArO at m/z 56 and 58, and ArOH at m/z 57. The ArN interference on 54Fe is not problematic if the HNO3 concentration in the standards and samples is identical. However, SLRS-4 was acidified to pH 1.6 with HNO3 (i.e. ~0.025 M) whereas the samples and standards are acidified to contain 1% cHNO3 (or ~0.16 M). This matrix mis-match could be expected to result in poor recovery for Fe. In addition, a small error in the acidification of analytical samples with nitric acid would result in an erroneous Fe concentration being reported.

In the Elan 6100DRC, polyatomic interferences such as ArN and ArO can be removed by the use of a reactive gas within the DRC (e.g. Olesik and Jones, 2006). The removal of interfering species (e.g. ArN), and control over the formation of additional species by the reactions occurring within the cell, is determined by the reaction gas used, the reaction gas flow rate, and the parameters RPa and RPq, which respectively relate to the DC voltage and the RF frequency applied to the quadrupole within the DRC. These parameters were optimised based upon manufacturer’s guidelines and through experiments conducted using SLRS-4 CRM since this has a known Fe concentration (103±5 µg/l).

2. To obtain UKAS Accreditation for an expanded range of elements.

The additional analytes included in Multi-element standard 2A (Li, V, Cr, Se, Sr, Sn, Sb, Cs, Ba, Tl and U) were added to the analytical method file. The isotopes, and instrument conditions (e.g. the mass spectrometer dwell time, the number of readings/replicate) were chosen based upon relative isotopic abundances, likely interferences, expected sample concentrations and a requirement that the total volume required for analysis be <10 ml. Methodological precision was assessed by repeated analyses of low and high standards, and accuracy by repeated analyses of SLRS-4 CRM and spiked samples. Single element standard solutions used for spiking were obtained from a different source to the quantitation standards. Shewhart Quality Control charts were then established.

3. To include the determination of Lanthanides and Th in the method.

A standard containing Lanthanide elements and Th was obtained and suitable isotopes added to the analytic method file. The isotopes and instrument conditions were selected as for Objective 2 and validation data were generated by repeated analyses of low and high standards, and spiked samples. The Lanthanide/Th solution used to prepare spiked samples was from a different supplier to that used to prepare the analytical standards. Shewhart Quality Control charts were also established for these elements.

4. To use the optimised method for the determination of trace element concentrations in

selected Scottish freshwaters.

Measurements of chloride concentration, alkalinity, trace metal concentrations, and temperature were obtained from 30 sites in a braided section of the river Feshie (NE Scotland), under low and high discharge conditions in 2006. The data were used in the PhD project to identify broad source water characteristics, and to link these with Atlantic salmon spawning areas.

FRS Method for the Determination of Trace Metals in Freshwaters

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Freshwater samples collected by FL from 38 locations in Galloway, SW Scotland in June 2006 were analysed by ICP-DRC-MS using the optimised method described in this report. The concentrations of 38 elements were determined and 14 of these were compared with the relevant Environmental Quality Standards used by SEPA for monitoring water quality under the EU Water Framework Directive (SEPA, 2004).

RESULTS To Improve Fe Determinations Before the improvement of Fe determinations was investigated, the concentration of Fe in SLRS-4 was determined 20 times (on 13 days) in 2004. This was done using 54Fe with the ICPMS in standard mode and the mean recovery was 75.1±2.9%. Figure 2 shows the recovery of Fe during optimisation of the DRC parameter RPq for 54Fe and 56Fe. The DRC parameter RPa was fixed at 0, following advice from the manufacturer. Optimal conditions for 54Fe were determined to be an RPq of 0.45 and an ammonia gas flow of 0.25 ml/min. For 56Fe, optimal conditions were an RPq of 0.7 and a gas flow of 0.25 ml/min. However, even under optimal conditions, the recovery for 56Fe was better (102±6.5%) than for 54Fe (96.2±3.5%; t-test p<0.01). In addition, 56Fe is the more abundant isotope and so also offers a lower detection limit; therefore, 56Fe was chosen as the preferred isotope for Fe determinations. Following DRC optimisation, repeated analysis (Table 1) of the low standard (0.5 ppb) was conducted to enable calculations of precision and detection limits (=4.65 x sd). The high standard (400 ppb) was also analysed repeatedly in order to assess precision at the top of the analytical range. A Shewhart quality control chart (Fig. 3) was established for 56Fe (with the limits based upon data from 20 points); the recovery on SLRS-4 CRM (mean±sd) was 102±6%. By comparison, the mean recovery for 54Fe by standard mode ICPMS continues to be approximately 75% (78±2.5 %). The Shewhart chart shows the method to be under good control with no fails (n=90). The revised, ICP-DRC-MS method was used for Fe determination in the 2006 NIVA proficiency testing round, with acceptable recovery being obtained for sample C, but high recovery for sample D (Table 2). The reason for this is under investigation. Fe concentrations determined as 56Fe (DRC) were compared to those determined as 54Fe (standard mode) for 38 freshwater samples collected by FL in June 2006 from sites in Galloway, SW Scotland. The two determinations produced highly comparable results, with no significant difference in the mean concentrations (t-test p=0.8). Validation of an expanded range of elements for UKAS Accreditation The isotopes (m/z) and mass spectrometer dwell times that were used in the ICPMS analysis for the expanded range of analytes are shown in Table 3. This table also summarises the mean recovery and precision from the analyses (n=10) of low and high standards under repeatability conditions (i.e. same instrument, same analyst, short time period), and the accuracy based upon repeated analysis of SLRS-4 CRM and spiked samples. Detection limits based upon 4.65 x standard deviation, and long-term QC chart parameters are also shown. With the exception of Se, all analytes show good precision (<2%) on the low and high standards, and have correspondingly low detection limits (<0.04 ppb). For Se the detection limit was <0.2 ppb and is judged fit for purpose. With the exception of Sb, all of the analytes show good recovery on the CRM or spiked sample (within 7% of the true value). The recovery for Sb is slightly higher at 117%. Long-term

FRS Method for the Determination of Trace Metals in Freshwaters

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performance indicates that the method is under good control, with low Shewhart chart failure rates (<2.5%, n=43-93; data not shown) for all of the extra analytes. Determination of Lanthanide elements and Th For the following elements a limited amount of validation data have been obtained: La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu, Yb and Th. The available validation data, isotopes used, and mass spectrometer dwell times are shown in Table 4. Concentrations of trace elements in Scottish freshwaters Freshwater samples collected by FL in June 2006 from 38 sites in Galloway, SW Scotland were analysed by ICP-DRC-MS using the optimised method as described above. The concentrations of 38 elements were determined and 14 of these compared to existing Environmental Quality Standards (EQS). The concentration data are summarised in Table 5, with full details by sampling site in the Appendix). For some elements, the EQS is dependant upon the CaCO3 concentration, with higher alkalinity waters having a higher EQS. In all of these samples the CaCO3 concentration was <50 mg/l (A. McCartney, pers. comm.) and thus the lowest EQSs were applicable. For three elements with defined EQSs (Cd, Sn and Hg), the concentrations in all samples were below the detection limits of the method. The Maximum Allowable Concentration EQS was exceeded at a limited number of sites for Mn (2 sites) and the EQS was exceed at 8 sites for Cu. Use of trace elements in determining source water contributions The influence of groundwater-surface water interactions on salmon spawning distributions was investigated as part of a NERC funded PhD project between FRS and the University of Aberdeen. Redd counts were carried out during 2005 and 2006 to establish spawning distributions. The river braids were mapped using superficial features (channel connections, spring source, hillslope origin, geomorphology likely to drive hyporheic exchange) to determine the likely influence of groundwater, short residence hillslope groundwater, and short residence surface/hyporheic waters. In 2006, a variety of methods were utilised in an effort to establish the validity of the qualitative classification scheme. In this PhD, trace metal data was combined with other hydrochemical data from 30 sites on the river Feshie in a Principle Components Analysis to identify broad source water characteristics. A sample output from the work is shown in Figure 4.

DISCUSSION To Improve Fe Determinations The change from standard mode to DRC mode for Fe determination has resulted in a much improved recovery on the Certified Reference Material (from 75% to 102%). However, the change did not significantly affect the concentrations of Fe as reported to FL for the samples collected in June 2006. The reason for this is that in standard mode 54Fe is subject to interference from 40Ar14N. This is unavoidable as the samples and CRM are acidified using HNO3. It is essential therefore to prepare the standards in a matrix containing exactly the same concentration of HNO3 as the samples. For FL freshwater samples, both the standards and samples contain 1% v/v cHNO3, however SLRS is acidified to pH 1.6 with HNO3 (i.e. ~0.025 M, or 0.16% v/v). Consequently the standards contain a higher N concentration, and have a greater ArN interference, than does SLRS, and consequently the recovery of Fe in SLRS appears low when analysed in standard mode. The use of the DRC mode for Fe determinations removes the ArN interference, giving good recovery on SLRS,

FRS Method for the Determination of Trace Metals in Freshwaters

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and ensuring that any slight errors in sample acidification would not affect the Fe results. The apparent low recovery at low concentration in the NIVA EQA samples may reflect the lack of a digestion step in the analytical method (e.g. through exposure to UV light) to destroy dissolved and colloidal organic material. Fe will bind to this, particularly at low concentrations, and this could explain the lower recovery obtained. However, this trend appears only on the basis of three samples with relatively low Fe concentrations, and additional data are required before this hypothesis can be substantiated. Validation of the determination of additional elements The expanded range of elements was assessed by UKAS at the annual site inspection in February 2007 and the determination of Li, V, Cr, Se, Sr, Sn, Sb, Cs, Ba, Tl and U was added to the Scope of Accreditation. Of these, Sb had a slight over recovery (117%) in SLRS, however, Sb had also been added to the spiked (0.8 ppb) sample, and in this the mean recovery was 98±1.8% (n=38; data not shown), possibly indicating that a slight matrix effect, rather than a memory effect, may be the cause of this over-recovery. The validation of Lanthanide and Th determinations shows good mean recoveries (98-101%; n=6) and precision (4.0-5.2% RSD), although a more limited amount of data is currently available than for the other elements. Use of trace elements in determining source water contributions Trace metals proved to be a very useful source water fingerprinting tool in both the River Feshie (described here) and the Girnock Burn. Together with temperature data, the trace metal data allowed the investigators an objective basis for establishing source water contributions that could not be obtained using superficial morphological characteristics, and that often contrasted with initial expectations. The data confirmed that spawning Atlantic salmon heavily utilised areas where the groundwater characteristics dominated surface waters. Concentrations of trace elements in Scottish freshwaters The utility of the ICP-DRC-MS method for the determination of trace elements was demonstrated by the analysis of 38 water samples collected in June 2006 from various sites in Galloway, SW Scotland. Concentrations were generally low, but some showed considerable variation between sites (RSDs were ~40-250%). Of the 26 additional elements in the method, six (Li, V, Cr, Sr, Sb, Ba) were present in all of the samples collected from sites in Galloway in June 2006, and six (Sn, Eu, Tb, Ho, Tm, Lu) were detected in less than 8% of the samples. Mn exceeded the MAC EQS (300 µg/l) for two sites, but Cu exceeded its EQS (0.5 µg/l) at eight sites. The EQS for Cu (and some other elements) was revised in 1993, and the SEPA EQS document (SEPA, 2004) notes that “whilst these revised values may be used operationally by Regulatory Authorities they have not been made directly statutory”. The Statutory EQS for Cu is 1 µg/l, for water with < 50 mg/l CaCO3 and three sites exceeded this limit. Of the 8 sites where Cu concentrations exceeded 0.5 ug/l, the majority were located close to Loch Grannach. This loch is situated at an altitude of 200m in an area characterised by forestry plantations and moorland; the high Cu concentrations are presumably a reflection of the local geology, rather than a point source of contamination.

REFERENCES FRS FL. 2006. Long-term Chemical and Biological Monitoring Programmes. Unpublished report to the Freshwater Fisheries and Aquaculture Division, Scottish Executive Rural Affairs Department, Edinburgh. Available from: Dr I. Malcolm, Fisheries Research Services, Freshwater Laboratory, Pitlochry. 18pp.

FRS Method for the Determination of Trace Metals in Freshwaters

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Harriman, R., Watt, A. W., Christie, A. E. G., Collen, P., Moore, D. W., McCartney, A. G., Taylor, E. M., and Watson, J. 2001. Interpretation of trends in acidic deposition and surface water chemistry in Scotland during the past three decades. Hydrology and Earth System Sciences, 5, 407-420. Harriman, R., Watt, A. W., Christie, A. E. G., Moore, D. W., McCartney, A. G., and Taylor, E. M. 2003. Quantifying the effects of forestry practices on the recovery of upland streams and lochs from acidification. Science of the Total Environment, 310, 101-111. McCartney, A. G., Harriman, R., Watt, A. W., Moore, D. W., Taylor, E. M., Collen, P., and Keay, E. J. 2003. Long-term trends in pH, aluminium and dissolved organic carbon in Scottish fresh waters; implications for brown trout (Salmo trutta) survival. Science of the Total Environment, 310, 133-141. Malcolm, I. A., Youngson, A. F., Soulsby, C., and Hannah, D. M. 2005. Catchment scale controls on groundwater – surface water interactions in the hyporheic zone: implications for salmon embryo survival. Rivers Research and Applications, 21, 977-989 Olesik, J. W., and Jones, D. R. 2006. Strategies to develop methods using ion-molecule reaction in a quadrupole reaction cell to overcome spectral overlaps in inductively coupled plasma mass spectrometry. Journal of Analytical Atomic Spectrometry, 21, 141-159. SEPA. 2004. Annex G Environmental Quality Standards (EQS) List. On-line citation, available from: http://www.sepa.org.uk/pdf/guidance/water/annexes/annex_g.pdf Scoulsby, C. Tetzlaff, D., van den Bedem, N., Malcolm, I.A., Bacon, P.J., and Youngson, A.F. 2006. Inferring groundwater influences on surface water in montane catchments from hydrochemical surveys of springs and streamwaters. Journal of Hydrology, 333, 199-213.

TABLES Table 1: Precision of Fe (DRC) analysis on spiked blanks and SLRS Certified Reference Material. Results of repeated (within-batch) analyses, used for calculation of precision and detection limits for Fe (56Fe using the ICPMS in DRC mode with ammonia gas (0.25 ml/min), an RPq value of 0.7 and an RPa value of 0).

Low std (0.5 µg/l) High std (400 µg/l) SLRS (103±5 µg/l) 1 0.688 406 102.1 2 0.654 405 100.1 3 1.996 408 104.2 4 0.651 407 98.0 5 0.654 410 100.6 6 0.509 409 103.2 7 0.496 412 104.3 8 0.513 409 105.6 9 0.517 410 10 0.507 411 Mean 0.719 409 102.3 SD 0.455 2.23 2.6 LoD (µg/l) 2.1 RSD% 63.4 0.55 2.5 Recovery (%) 99.3

Table 2: External Quality Control data for Fe (56Fe using the ICPMS in DRC mode with ammonia gas (0.25 ml/min), an RPq value of 0.7 and an RPa value of 0).

Assigned (µg /l)

Reported (µg/l) Recovery %

Sample C 539 553 102.6 Sample D 439 568 129.4

Table 3: Method performance for the extended range of analytes. Limit of Detection (LoD) calculated based upon 4.65 x sd of the low standard. For the Shewhart control chart, LCL = lower control limit; LWL = lower warning limit; UWL = upper warning limit; UCL = upper control limit; warning limits are 2xSD, control limits are 3xSD. Concentrations outwith the control values, or two consecutive points outwith the warning limits, are failed and the samples reanalysed.

Precision -low std (µg/l) High std (µg/l) SLRS/ spiked sample (n=10) Shewhart chart (µg/l; n=43-93) Analyte m/z Dwelltime

(ms) mean sd rsd (%) LoD mean sd rsd

(%) True (µg/l) Recovery (%) sd rsd

(%) Material LCL LWL Mean UWL UCL

Li 7 25 0.505 0.004 0.8 0.019 54.7 0.20 0.4 2 99.9 5.3 5.3 SLRS 0.419 0.445 0.496 0.548 0.574V 51 25 0.491 0.004 0.8 0.017 51.8 0.15 0.3 0.32±0.03 106.3 3.9 3.6 SLRS 0.276 0.304 0.361 0.418 0.446Cr 52 25 0.475 0.008 1.7 0.037 51.7 0.17 0.3 0.33±0.02 94.5 9.2 9.7 SLRS 0.157 0.219 0.342 0.465 0.527Se 82 50 0.485 0.042 8.6 0.195 52.3 0.26 0.5 2 101.8 6.0 5.9 SLRS 0.151 0.243 0.426 0.609 0.701Sr 88 25 0.499 0.004 0.7 0.017 54.9 0.15 0.3 26.3±3.2 106.0 2.2 2.1 SLRS 25.01 25.92 27.74 29.56 30.47Sn 120 50 0.476 0.004 0.8 0.017 0.755 0.003 0.5 0.8 95.4 1.4 1.5 Spike 0.699 0.720 0.762 0.804 0.826Sb 121 25 0.488 0.005 1.0 0.022 0.763 0.005 0.7 0.23±0.04 117.0 2.3 2.0 SLRS 0.249 0.255 0.267 0.278 0.284Cs 133 25 0.509 0.003 0.6 0.013 49.4 0.15 0.3 2 101.3 3.2 3.2 Spike 1.767 1.843 1.995 2.148 2.224Ba 137 25 0.497 0.007 1.4 0.032 50.7 0.12 0.2 12.2±0.6 105.2 2.0 1.9 SLRS 11.11 11.61 12.63 13.65 14.16Tl 205 50 0.492 0.002 0.4 0.010 53.8 0.37 0.7 2 99.0 2.9 2.9 Spike 1.766 1.838 1.983 2.127 2.200U 238 50 0.512 0.003 0.5 0.013 56.9 0.59 1.0 0.05±0.003 99.0 4.0 4.1 SLRS 0.042 0.042 0.050 0.055 0.058

Table 4: Method performance for Lanthanide elements and thorium. Limit of Detection (LoD) calculated based upon 4.65 x sd of the low standard.

Precision - low std (µg/l) Precision - high std (µg/l)

Recovery on spiked sample (n=7) Shewhart chart (µg/l; n=9)

Analyte m/z Dwelltime (ms) mean sd rsd

(%) LoD mean sd rsd (%)

True (µg/l)

Recovery (%) sd rsd

(%) LCL LWL Mean UWL UCL

La 139 25 0.253 0.003 1.14 0.013 0.989 0.006 0.57 0.8 98.8 4.5 4.6 0.682 0.718 0.790 0.862 0.898 Ce 140 25 0.254 0.002 0.81 0.010 1.000 0.004 0.37 0.8 99.3 4.0 4.0 0.698 0.730 0.794 0.859 0.891 Pr 141 25 0.255 0.003 1.31 0.015 1.003 0.003 0.32 0.8 99.4 4.2 4.2 0.694 0.727 0.795 0.862 0.896 Nd 142 25 0.254 0.005 1.90 0.022 1.001 0.006 0.64 0.8 98.9 4.2 4.3 0.690 0.724 0.791 0.859 0.893 Sm 149 25 0.255 0.001 0.54 0.006 1.008 0.007 0.74 0.8 99.1 4.5 4.6 0.684 0.720 0.793 0.866 0.902 Eu 151 25 0.256 0.002 0.67 0.008 1.015 0.008 0.79 0.8 98.5 4.2 4.3 0.687 0.721 0.788 0.856 0.889 Gd 158 25 0.255 0.005 1.81 0.021 1.005 0.006 0.61 0.8 99.1 3.4 3.5 0.711 0.738 0.793 0.848 0.876 Tb 159 25 0.254 0.003 1.19 0.014 1.005 0.006 0.59 0.8 99.0 4.1 4.1 0.694 0.727 0.792 0.857 0.890 Dy 164 25 0.258 0.003 1.19 0.014 1.014 0.010 1.03 0.8 98.0 3.8 3.9 0.694 0.724 0.784 0.845 0.875 Ho 165 25 0.258 0.001 0.32 0.004 1.013 0.007 0.69 0.8 98.3 4.1 4.1 0.689 0.721 0.786 0.851 0.883 Er 166 25 0.254 0.003 1.10 0.013 1.004 0.005 0.48 0.8 97.4 4.6 4.7 0.670 0.706 0.779 0.852 0.888 Tm 169 25 0.256 0.003 1.14 0.014 1.006 0.006 0.62 0.8 97.3 4.7 4.8 0.666 0.703 0.779 0.854 0.892 Lu 175 25 0.255 0.003 1.16 0.014 1.006 0.008 0.82 0.8 97.9 4.0 4.0 0.688 0.720 0.783 0.846 0.878 Yb 174 25 0.255 0.003 1.05 0.012 1.008 0.010 1.03 0.8 97.4 3.9 4.0 0.685 0.716 0.779 0.842 0.874 Th 232 25 0.256 0.002 0.77 0.009 1.013 0.013 1.33 0.8 97.2 3.8 3.9 0.686 0.716 0.778 0.839 0.869

Table 5: Concentrations of trace elements determined in freshwater sampled from Galloway in June 2006, and compared with existing Environmental Quality Standards (EQSs; SEPA, 2004). For results that were below Detection Limit (DL), the DL x 0.5 was used to calculate concentration statistics. AA=annual average, MAC=Maximum Allowable Concentration. *The EQS depends upon CaCO3 concentration, for these samples the lowest EQS was appropriate.

Concentration (µg/l)Element EQS (µg/l) AA (MAC) Mean±SD Median±95% CI Min Max

No. <DL

No. > EQS

Li 1.08 ± 1.26 0.40 ± 0.67 0.235 5.27 0 0 Al 132.2 ± 82.0 121.8 ± 0.40 26.9 376 0 0 V 20* 0.263 ± 0.108 0.2 48 ± 26.1 0.115 0.621 0 0 Cr 2* 0.186 ± 0.086 0.172 ± 0.034 0.075 0.448 0 0 Fe 1000 152.9 ± 177.4 98.9 ± 0.027 20.3 881 0 0 Fe (DRC) 1000 141.8 ± 153.5 97.7 ± 48.8 21.2 777 0 0 Mn 30 (300) 70.1 ± 181.6 14.8 ± 57.7 1.09 1087 0 2 Ni 8* 0.37 ± 0.20 0.38 ± 0.07 <0.191 0.85 8 0 Co 3 (100) 0.12 ± 0.20 0.06 ± 0.07 0.018 1.14 0 0 Cu 0.5* 0.404 ± 0.278 0.294 ± 0.088 0.14 1.24 0 8 Zn 8* 2.79 ± 1.45 2.87 ± 0.46 0.589 6.12 0 0 As 50 0.599 ± 0.477 0.449 ± 0.154 <0.217 2.48 1 0 Se 0.277 ± 0.177 0.241 ± 0.066 <0.195 0.80 10 Sr 6.93 ± 3.46 6.40 ± 1.10 3.25 20.4 0 Y 0.118 ± 0.111 0.085 ± 0.035 0.029 0.58 0 Cd 5 <0.194 <0.194 38 0 Sn 25 <0.010 <0.01 38 0 Sb 0.085 ± 0.026 0.081 ± 0.008 0.048 0.153 0 Cs 0.047 ± 0.029 0.048 ± 0.009 <0.013 0.175 2 Ba 2.21 ± 1.16 1.93 ± 0.37 0.799 5.41 0 La 0.127 ± 0.116 0.095 ± 0.037 0.023 0.664 0 Ce 0.318 ± 0.398 0.209 ± 0.126 0.028 2.27 0 Pr 0.029 ± 0.026 0.026 ± 0.023 <0.015 0.146 5 Nd 0.111 ± 0.098 0.086 ± 0.031 0.022 0.537 1 Sm 0.023 ± 0.023 0.016 ± 0.008 <0.006 0.118 10 Eu 0.006 ± 0.002 0.005 ± 0.002 <0.008 0.014 35 Gd 0.028 ± 0.030 0.011 ± 0.010 <0.022 0.155 21 Tb <0.014 <0.014 38 Dy 0.018 ± 0.018 0.007 ± 0.006 <0.014 0.093 20 Ho 0.006 ± 0.003 0.005 ± 0.003 <0.004 0.018 35 Er 0.011 ± 0.010 0.007 ± 0.005 <0.013 0.053 25 Tm <0.014 0.005 38 Yb 0.011 ± 0.009 0.006 ± 0.005 <0.012 0.047 25 Lu <0.014 <0.01 38 Hg 1 <0.010 <0.01 38 0 Tl 0.011 ± 0.009 0.011 ± 0.004 <0.010 0.050 16 Pb 4* 0.569 ± 0.413 0.464 ± 0.141 <0.162 1.52 5 0 Th 0.016 ± 0.015 0.008 ± 0.007 <0.009 0.057 19 U 0.701 ± 1.226 0.198 ± 0.446 <0.013 6.88 9

FIGURES Figure 1: Results of Fe determinations in samples for the NIVA external quality assurance scheme. A) Recovery by round and sample

0

20

40

60

80

100

120

140

2002 2004 2005 2006

Year

Rec

over

y (%

)

Sample C Sample D

B) Recovery by assigned concentration

0

20

40

60

80

100

120

140

0 100 200 300 400 500 600

Assigned Concn (ug/l)

Rec

over

y (%

)

Figure 2: Optimisation of dynamic reaction cell parameters for determination of Fe (recovery compared to SLRS-4 Certified Reference Material (certified Fe conc = 103±5 µg/l)

70

80

90

100

110

120

0 0.4 0.45 0.5* 0.6 0.6** 0.7 0.75

RPq (0=std mode)NH3 gas flow = 0.25 ml/min, except *=0.3 and **=0.5

Rec

over

y (%

)

Fe54Fe56

Figure 3: Shewhart quality control chart for 56Fe in SLRS-4 Certified Reference Material following optimisation of dynamic reaction cell parameters

Fisheries Research ServicesSLRS4 - Freshwater LRM

Iron 56 by DRC (ug/l)

Individ.: cl: 104.695 ucl: 123.137 lcl: 86.2533Subgrp Size 1

Target: 103

Con

cent

ratio

n (u

g/l)

25

25

25

2525

26

26

26

2626

27

27

27

27

35

3535

3535

3636363636

37

3737

37

3838

3838

3939

393939

4040

40

40

40

4242

4343

4444

44

44

44

454545

484848

48

48

4949

50505050

50

5151

5152

53

535353

5353

54

54

56

56

56

57

58

58

585859

60

60

61

6262

Individ.

cl

lwl

uwl

lcl

ucl

Target

90

100

110

120

ROW:BATCH:

733110

943160

1153243

1353243

1563334

1773441

1983455

2193793

Figure 4: PCA plot showing the chemical characteristics of sites in relation to components 1 and 2. Polygons indicate designation of source waters according to multi-proxy approach including trace metal PCA. Determinants showing major component loadings are indicated on the relevant axes.

APPENDIX – ELEMENTAL CONCENTRATIONS (ug/l) IN FRESHWATER SAMPLES COLLECTED FROM GALLOWAY IN JUNE 2006 UKAS ID Site Name Grid Ref CaCO3 Li Al V Cr Fe Fe DRC Mn Co Ni Cu Zn As Se

Limit of Detection: (mg/l) 0.019 0.196 0.017 0.037 1.65 2.12 0.094 0.007 0.099 0.202 0.34 0.045 0.1954350/06 LOCH DUNGEON NX528842 0.65 0.279 88.3 0.120 0.150 38.8 36.7 15.6 0.106 0.281 0.367 4.59 0.236 <DL 4351/06 HAWSE BURN NX521846 2.45 0.263 40.8 0.115 0.091 28.4 27.1 3.7 0.051 <DL 0.209 1.36 0.405 0.2074352/06 LOCH MINNOCH NX533857 1.40 0.290 95.5 0.173 0.164 78.0 73.7 15.1 0.060 0.388 0.893 3.37 1.571 <DL 4353/06 LOCH HARROW NX533867 0.55 0.320 128 0.184 0.176 137 132 42.8 0.262 0.680 0.432 4.61 0.581 <DL4354/06 FOLK BURN NX527870 5.95 0.334 58.2 0.179 0.126 37.6 35.9 3.9 0.040 0.438 0.246 1.16 0.422 0.281 4355/06 LOCH DOON NS478006 1.05 0.360 132 0.284 0.261 201 193 23.2 0.097 0.667 0.408 5.48 0.580 0.3274356/06 LOCH RIECAWR NX442937 0.85 0.310 120 0.312 0.332 236 225 28.4 0.087 0.712 0.639 3.66 0.937 0.343 4357/06 TUNSKEEN LANE NX434912 3.50 0.239 38.9 0.198 0.243 156 149 3.9 0.034 0.377 0.191 0.87 0.590 0.3494358/06 LOCH MACATERICK NX444911 0.40 0.269 97.7 0.233 0.250 203 195 51.0 0.047 0.595 0.427 3.95 0.525 0.268 4359/06 LOCH VALLEY NX438818 -0.10 0.352 130 0.263 0.199 45.9 43.9 11.0 0.063 0.852 0.209 3.43 0.226 0.198 4360/06 LOCH ENOCH NX444857 -0.50 0.297 83.9 0.263 0.147 49.3 46.4 6.7 0.064 0.348 0.247 3.14 <DL 0.178 4361/06 LOCH ARRON NX444837 -0.15 0.261 140 0.509 0.269 67.2 64.5 10.3 0.088 0.506 0.257 3.58 0.441 0.226 4362/06 LOCH NELDRICKEN NX443825 0.20 0.403 131 0.300 0.191 52.0 49.8 9.1 0.059 0.442 0.272 3.48 0.289 0.232 4363/06 LOCH NARROCH NX453815 -0.10 0.408 157 0.347 0.178 72.1 68.8 8.5 0.060 0.420 0.225 3.73 0.238 0.219 4364/06 LONG LOCH OF GLENHEAD NX446806 0.35 0.235 109 0.273 0.202 83.4 84.0 9.4 0.069 0.349 0.276 3.05 0.366 <DL 4365/06 ROUND LOCH OF GLENHEAD NX448802 -0.20 0.308 123 0.209 0.171 44.0 44.3 14.4 0.086 0.379 0.227 3.82 0.264 <DL4366/06 DARGALL LANE NX449786 1.70 0.270 34.1 0.124 0.093 20.3 21.3 1.1 0.034 0.694 0.173 1.67 0.952 <DL 4367/06 WHITE LAGGAN BURN NX468776 5.10 0.237 26.9 0.164 0.168 28.2 29.1 4.3 0.035 0.472 0.182 1.03 0.248 <DL 4368/06 BLACK LAGGAN BURN NX469777 5.95 0.245 26.9 0.178 0.207 32.9 32.5 8.4 0.035 0.384 0.227 1.17 0.641 0.247 4369/06 GREEN BURN NX478793 4.55 0.404 77.9 0.291 0.442 262 265 21.7 0.093 0.473 0.207 0.589 0.522 0.235 4370/06 LOCH DEE OUTFLOW NX478797 1.25 0.236 49.5 0.154 0.171 32.0 33.0 8.0 0.021 0.369 0.509 1.28 0.398 <DL 4371/06 LONG LOCH OF THE DUNGEON NX467838 0.60 0.863 128 0.198 0.118 118 118 23.1 0.029 0.253 0.188 2.36 0.280 <DL 4372/06 ROUND LOCH OF THE DUNGEON NX466848 0.45 0.796 132 0.202 0.110 125 125 33.5 0.024 0.221 0.420 3.15 0.298 0.2184373/06 DRY LOCH OF THE DUNGEON NX467858 -0.25 0.499 119 0.204 0.099 20.9 21.2 9.4 0.048 <DL 0.136 2.70 0.148 0.2174374/06 LOCH GRANNOCH OUTFLOW (PULLAUGH BURN) NX548715 -0.65 1.11 222 0.306 0.180 166 168 122 0.183 0.449 0.339 5.79 0.456 0.250 4375/06 LOCH GRANNOCH INFLOW 4 (CUTTIE SHALLOW BURN) NX543708 2.70 4.94 263 0.621 0.448 593 497 108 0.564 0.556 0.709 2.50 1.07 0.487 4376/06 LOCH GRANNOCH INFLOW 5 (CUTTIEMORE BURN) NX537699 0.55 2.95 100 0.205 0.110 87.9 87.5 13.8 0.028 <DL 0.177 1.59 0.348 0.275 4377/06 LOCH GRANNOCH INFLOW 1 NX552714 2.60 2.80 376 0.362 0.234 881 777 1087 1.138 0.439 0.702 3.82 0.998 0.7884378/06 LOCH GRANNOCH INFLOW 2 NX552712 0.95 1.58 219 0.148 0.131 110 110 90.2 0.080 <DL 1.062 1.79 0.388 0.8004379/06 LOCH GRANNOCH INFLOW 3 NX547698 3.95 1.76 305 0.437 0.266 531 451 326 0.493 0.348 0.449 4.23 1.38 0.5594380/06 LOCH GRANNOCH INFLOW 6 (LODGE BURN) NX537686 1.00 1.17 143 0.368 0.098 51.4 49.0 8.8 0.026 <DL 0.228 2.34 0.538 0.296 4381/06 LOCH GRANNOCH LODGE BAY NX540685 -0.50 1.16 238 0.319 0.173 162 154 110 0.170 0.371 0.372 6.12 0.504 0.2984382/06 CARROUCH BURN NX546666 1.50 1.98 85.2 0.209 0.075 26.5 26.2 4.1 0.018 <DL 0.210 1.07 0.284 <DL 4383/06 MID BURN NX546661 4.35 1.24 61.7 0.220 0.087 112 108 13.5 0.030 <DL 0.311 0.789 0.345 0.310 4384/06 CARDOON BURN NX547660 8.35 5.27 58.6 0.343 0.126 161 154 17.3 0.053 <DL 1.117 1.59 0.597 0.3364385/06 CRAIGLOWRIE BURN NX553670 1.00 1.42 256 0.320 0.166 182 175 68.3 0.074 0.245 1.242 3.10 0.599 0.398 4386/06 BENMEAL BURN NX558657 1.30 2.98 230 0.359 0.207 359 306 208 0.190 0.319 0.370 1.96 1.51 0.588 4387/06 LITTLE WATER OF FLEET NX587672 0.60 2.16 197 0.311 0.190 219 210 119 0.092 0.380 0.482 2.07 2.48 0.403

i

APPENDIX – ELEMENTAL CONCENTRATIONS (µg/l) IN FRESHWATER SAMPLES FROM GALLOWAY (cont) UKAS ID Grid Ref Sr Cd Sn Sb Cs Ba Hg Tl Pb U La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Lu Yb Th

Limit of Detection: 0.017 0.018 0.017 0.022 0.013 0.032 0.011 0.01 0.015 0.013 0.013 0.010 0.015 0.022 0.006 0.008 0.021 0.014 0.014 0.004 0.013 0.014 0.014 0.012 0.009 4350/06 NX528842 5.72 <DL <DL 0.070 0.014 3.53 <DL <DL 0.255 <DL 0.063 0.072 <DL 0.042 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4351/06 NX521846 8.11 <DL <DL 0.052 0.014 3.34 <DL <DL <DL <DL 0.023 0.028 0.005 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL4352/06 NX533857 6.49 <DL <DL 0.084 0.015 3.16 <DL <DL 0.203 <DL 0.046 0.075 <DL 0.044 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL4353/06 NX533867 6.34 <DL <DL 0.067 <DL 3.37 <DL <DL 0.404 <DL 0.083 0.157 0.020 0.078 0.016 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4354/06 NX527870 20.4 <DL <DL 0.057 <DL 3.47 <DL <DL <DL <DL 0.039 0.036 0.009 0.034 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL4355/06 NS478006 7.64 <DL <DL 0.068 0.020 3.02 <DL <DL 0.424 0.060 0.114 0.232 0.029 0.122 0.024 <DL 0.028 <DL 0.021 <DL <DL <DL <DL <DL 0.0164356/06 NX442937 6.73 <DL <DL 0.056 0.029 3.03 <DL <DL 0.451 0.018 0.088 0.180 0.023 0.088 0.016 <DL <DL <DL 0.014 <DL <DL <DL <DL <DL 0.011 4357/06 NX434912 8.86 <DL <DL 0.050 0.036 1.14 <DL <DL 0.183 0.030 0.047 0.092 <DL 0.047 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 0.021 4358/06 NX444911 4.76 <DL <DL 0.074 0.027 1.63 <DL <DL 0.435 0.027 0.086 0.185 0.021 0.075 0.015 <DL <DL <DL <DL <DL <DL <DL <DL <DL 0.014 4359/06 NX438818 4.17 <DL <DL 0.081 0.057 1.44 <DL 0.013 0.734 0.167 0.148 0.313 0.030 0.100 0.016 <DL <DL <DL <DL <DL <DL <DL <DL <DL 0.017 4360/06 NX444857 3.33 <DL <DL 0.082 0.038 1.17 <DL <DL 0.704 0.072 0.062 0.134 0.015 0.054 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4361/06 NX444837 3.70 <DL <DL 0.097 0.047 1.28 <DL 0.015 0.968 0.057 0.076 0.160 0.017 0.066 0.011 <DL <DL <DL <DL <DL <DL <DL <DL <DL 0.018 4362/06 NX443825 4.28 <DL <DL 0.083 0.065 0.952 <DL 0.015 0.731 0.238 0.157 0.326 0.033 0.108 0.019 <DL 0.022 <DL <DL <DL <DL <DL <DL <DL 0.0194363/06 NX453815 3.25 <DL <DL 0.091 0.060 1.51 <DL 0.014 1.01 0.228 0.198 0.447 0.041 0.141 0.023 <DL 0.028 <DL 0.014 <DL <DL <DL <DL <DL 0.0244364/06 NX446806 6.83 0.081 <DL <DL 0.047 1.51 <DL 0.014 0.920 0.053 0.081 0.179 0.020 0.067 0.010 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4365/06 NX448802 4.89 <DL <DL 0.075 0.049 2.00 <DL 0.014 0.774 0.118 0.125 0.262 0.025 0.085 0.015 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4366/06 NX449786 8.68 <DL <DL 0.054 0.029 5.00 <DL 0.012 0.266 <DL 0.039 0.046 <DL 0.031 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL4367/06 NX468776 9.25 <DL <DL 0.065 0.034 3.28 <DL <DL <DL <DL 0.027 0.033 0.006 0.025 0.005 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4368/06 NX469777 8.33 <DL <DL 0.064 0.027 1.99 <DL <DL <DL <DL 0.026 0.033 0.007 0.029 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL4369/06 NX478793 8.70 <DL <DL 0.048 0.034 2.81 <DL <DL 0.194 0.030 0.082 0.163 0.022 0.084 0.016 <DL <DL <DL 0.015 <DL <DL <DL <DL <DL <DL 4370/06 NX478797 5.87 <DL <DL 0.071 0.031 2.44 <DL <DL <DL <DL 0.032 0.047 0.007 0.028 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL4371/06 NX467838 4.41 <DL <DL 0.087 0.060 0.799 <DL <DL 0.530 0.603 0.072 0.147 0.017 0.063 0.014 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4372/06 NX466848 4.77 <DL <DL 0.082 0.062 1.31 <DL <DL 0.476 1.018 0.063 0.120 <DL 0.055 0.011 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4373/06 NX467858 5.33 <DL <DL 0.070 0.048 1.69 <DL 0.010 0.573 0.404 0.102 0.126 0.020 0.070 0.013 <DL <DL <DL <DL <DL <DL <DL <DL <DL <DL 4374/06 NX548715 4.31 <DL <DL 0.121 0.049 2.29 <DL 0.026 1.07 0.563 0.145 0.447 0.035 0.143 0.030 <DL 0.037 <DL 0.021 <DL 0.013 <DL <DL <DL <DL4375/06 NX543708 8.58 <DL <DL 0.098 0.054 1.01 <DL 0.015 1.40 1.51 0.314 0.969 0.077 0.305 0.071 0.014 0.092 <DL 0.065 0.013 0.036 <DL <DL 0.034 <DL4376/06 NX537699 5.16 <DL <DL 0.082 0.042 0.923 <DL 0.012 0.305 0.596 0.087 0.266 0.023 0.086 0.022 <DL 0.024 <DL 0.018 <DL <DL <DL <DL 0.013 <DL 4377/06 NX552714 7.11 <DL <DL 0.122 0.175 5.41 <DL 0.050 1.47 1.52 0.664 2.274 0.146 0.537 0.118 <DL 0.155 <DL 0.093 0.018 0.053 <DL <DL 0.047 0.054 4378/06 NX552712 3.31 <DL <DL 0.105 0.059 2.55 <DL 0.010 0.236 2.211 0.328 1.000 0.079 0.295 0.070 0.013 0.086 <DL 0.056 0.011 0.033 <DL <DL 0.034 0.0574379/06 NX547698 8.87 <DL <DL 0.130 0.090 1.86 <DL 0.025 1.52 0.430 0.185 0.520 0.047 0.179 0.041 0.010 0.051 <DL 0.032 <DL 0.019 <DL <DL 0.016 0.022 4380/06 NX537686 4.83 <DL <DL 0.138 0.045 4.03 <DL 0.011 0.565 6.88 0.106 0.298 0.029 0.118 0.031 <DL 0.037 <DL 0.025 <DL 0.014 <DL <DL 0.015 0.045 4381/06 NX540685 4.52 <DL <DL 0.123 0.051 2.56 <DL 0.017 1.14 0.854 0.147 0.450 0.036 0.139 0.029 <DL 0.038 <DL 0.023 <DL 0.013 <DL <DL 0.012 0.026 4382/06 NX546666 6.20 <DL <DL 0.075 0.059 1.23 <DL 0.012 0.200 1.96 0.128 0.247 0.028 0.102 0.024 <DL 0.030 <DL 0.022 <DL 0.013 <DL <DL 0.012 0.015 4383/06 NX546661 9.49 <DL <DL 0.081 0.070 0.876 <DL 0.011 0.149 0.785 0.133 0.292 0.033 0.135 0.033 <DL 0.037 <DL 0.027 <DL 0.017 <DL <DL 0.016 0.043 4384/06 NX547660 17.7 <DL <DL 0.076 0.050 2.18 <DL 0.011 0.341 1.22 0.111 0.253 0.029 0.123 0.030 <DL 0.034 <DL 0.023 <DL 0.014 <DL <DL 0.014 0.034 4385/06 NX553670 8.09 <DL <DL 0.109 0.051 1.40 <DL 0.012 0.800 1.85 0.186 0.433 0.042 0.158 0.035 <DL 0.045 <DL 0.026 <DL 0.014 <DL <DL 0.014 0.027 4386/06 NX558657 7.94 <DL <DL 0.108 0.080 1.71 <DL 0.021 1.04 1.31 0.256 0.597 0.056 0.216 0.049 <DL 0.059 <DL 0.035 <DL 0.019 <DL <DL 0.016 0.035 4387/06 NX587672 6.47 <DL <DL 0.153 0.071 0.968 <DL 0.012 0.748 1.75 0.166 0.440 0.040 0.153 0.037 <DL 0.043 <DL 0.025 <DL 0.014 <DL <DL 0.014 0.028

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