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Comparison of source-location algorithms for atmospheric samplers

Numerous algorithms have been developed to determine the source characteristics for an atmospheric release, e.g., (Bieringer et al., 2017). This study compares three models that have been applied to the data collected by the International Monitoring System operated by the Comprehensive Nuclear-Test-Ban Treaty Preparatory Commission to estimate source event parameters. Each model uses a different approach to estimate the parameters. A deterministic model uses a possible source region (PSR) approach (Ringbom et al., 2014) that is based on the correlation between predicted and measured sample values. An unnamed model developed at Pacific Northwest National Laboratory (herein called BAYEST) uses a Bayesian formulation (Eslinger et al., 2019; Eslinger et al., 2020; Eslinger and Schrom, 2016). The FREAR model uses a different Bayesian formulation (De Meutter and Hoffman, 2020; De Meutter et al., 2021; Pieter De Meutter, 2021). The performance of the three source-location models is evaluated with 100 synthetic release cases for the single xenon isotope, 133 Xe. The release cases resulted in detections in a fictitious network with 120 noble gas samplers. All three source-location models use the same sampling data. The two Bayesian models yield more accurate location estimates than the deterministic PSR model, with FREAR having slightly better location performance than BAYEST. Samplers with collection periods of 3, 6, 8, 12, and 24-h were used. Results from BAYEST show that location accuracy improves with each reduction in sample collection length. The BAYEST model is slightly better for estimating the start time of the release. The PSR model has about the same spread in start times as the FREAR model, but the PSR results have a better average start time. The Bayesian source-location algorithms give more accurate results than the PSR approach, and provide release magnitude estimates, while the base PSR model does not estimate the release magnitude. This investigation demonstrates that a reasonably dense sampling grid will sometimes yield poor location and time estimates regardless of the model. The poor estimates generally coincide with cases where there is a much larger distance between the release point and the first detecting sampler than the average sampler spacing.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

Idealized simulation study of the relationship of disdrometer sampling statistics with the precision of precipitation rate measurement

Due to the discretized nature of rain, the measurement of a continuous precipitation rate by disdrometers is subject to statistical sampling errors. Here, Monte Carlo simulations are employed to obtain the precision of rain detection and rate as a function of disdrometer collection area and compared with World Meteorological Organization guidelines for a 1 min sample interval and 95 % probability. To meet these requirements, simulations suggest that measurements of light rain with rain rates R ≤ 0.50 mm h-1 require a collection area of at least 6 cm × 6 cm, and for R = 1 mm h -1 , the minimum collection area is 13 cm × 13 cm. For R = 0.01 mm h -1 , a collection area of 2 cm × 2 cm is sufficient to detect a single drop. Simulations are compared with field measurements using a new hotplate device, the Differential Emissivity Imaging Disdrometer. The field results suggest an even larger plate may be required to meet the stated accuracy, likely in part due to non-Poissonian hydrometeor clustering.

54 ENVIRONMENTAL SCIENCES↗

2022 Results for Avian Monitoring of Inorganic Elements and Organic Chemical Concentrations in Passerine Eggs and Nestlings Collected from Technical Area 16 Burn Grounds, Technical Area 36 Minie, and Technical Area 39 Point 6 at Los Alamos National Laboratory

In 2022, nonviable avian eggs and one nestling were opportunistically collected at Los Alamos National Laboratory (LANL) near open detonation sites located at Technical Area (TA) 16 burn grounds, TA-36 Minie, and TA-39 Point 6. Samples were evaluated for inorganic elements (mostly metals) or per- and polyfluoroalkyl substances (PFAS). Three western bluebird (Sialia mexicana) egg samples were collected from TA-16 burn grounds. One deceased mountain bluebird (Sialia currucoides) nestling sample was collected from TA-36 Minie. One ash-throated flycatcher (Myiarchus cinerascens) egg sample was collected from TA-39 Point 6. Concentrations of inorganic elements (i.e., mostly metals) observed in this study were compared with the regional statistical reference level (RSRL), which is the upper-level bounds of background concentrations (mean + three standard deviations = 99% confidence interval). Several inorganic elements were not detected in avian eggs. All of the inorganic elements that were detected were below the RSRL and the lowest observable adverse effect level (LOAEL), when available. No PFAS compounds were detected in the mountain bluebird nestling sample collected from TA-36, and the majority of PFAS compounds were not detected in the western bluebird egg sample from TA-16. These data suggest that inorganic element and PFAS concentrations in eggs and nestlings are not of ecological concern. More data are needed to make a robust assessment and to evaluate trends over time.

59 BASIC BIOLOGICAL SCIENCES↗

Properties of Cosmic Lithium Isotopes Measured by the Alpha Magnetic Spectrometer

We present the first measurement of cosmic-ray fluxes of 6 Li and 7 Li isotopes in the rigidity range from 1.9 to 25 GV. The measurements are based on 9.7 × 10 5 6 Li and 1.04 × 10 6 7 Li nuclei collected by the Alpha Magnetic Spectrometer on the International Space Station from May 2011 to October 2023. We observe that over the entire rigidity range the 6 Li and 7 Li fluxes exhibit nearly identical time variations and, above ∼4 GV, the time variations of 6 Li , 7 Li , He, Be, B, C, N, and O fluxes are identical. Above ∼7 GV, we find an identical rigidity dependence of the 6 Li and 7 Li fluxes. This shows that they are both produced by collisions of heavier cosmic-ray nuclei with the interstellar medium and, in particular, excludes the existence of a sizable primary component in the 7 Li flux.

cosmic ray acceleration↗

Fission TPC FY2020 Report (Mid Q2 FY2021): Preliminary 235 U(n,f)/ 6 Li(n,t)α Cross Section Ratio Analysis & Update on the 239 Pu(n,f) Data Collection

Fission TPC L2 Milestone Description: The fission TPC experimental campaign is in its final stages of collecting high precision (n,f) cross section data aimed at improving our understanding of the 239 Pu fission process. During FY 2019 235 U(n,f)/ 6 Li(n,t) ratio data collection began at WNR/LANSCE. This data is the first step in demonstrating the efficacy of 6 Li(n,t) as a diagnostic standard for a 239 Pu(n,f) ratio measurement. In FY 2020 and FY2021, the NIFFTE Collaboration will analyze 235 U(n,f)/ 6 Li(n,t) data already collected to establish this technique in preparation for 239 Pu(n,f)/ 6 Li(n,t) ratio data. Additionally, the ability to vapor deposit 239 Pu was developed in 2019, greatly improving target quality. As access to experimental facilities allows, 239 Pu/ 235 U and 239 Pu/ 6 Li data will be collected to provide new inputs for evaluation of the 239 Pu(n,f) cross section.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Tuning collective anion motion enables superionic conductivity in solid-state halide electrolytes

Halides of the family Li 3 MX 6 (M = Y, In, Sc and so on, X = halogen) are emerging solid electrolyte materials for all-solid-state Li-ion batteries. They show greater chemical stability and wider electrochemical stability windows than existing sulfide solid electrolytes, but have lower room-temperature ionic conductivities. Here, in this work, we report the discovery that the superionic transition in Li 3 YCl 6 is triggered by the collective motion of anions, as evidenced by synchrotron X-ray and neutron scattering characterizations and ab initio molecular dynamics simulations. Based on this finding, we used a rational design strategy to lower the transition temperature and thus improve the room-temperature ionic conductivity of this family of compounds. We accordingly synthesized Li 3 YCl x Br 6-x and Li 3 GdCl 3 Br 3 and achieved very high room-temperature conductivities of 6.1 and 11 mS cm -1 for Li 3 YCl 4.5 Br 1.5 and Li 3 GdCl 3 Br 3 , respectively. These findings open new routes to the design of room-temperature superionic conductors for high-performance solid batteries.

25 ENERGY STORAGE↗

Genetic Predictive Factors for Nonsusceptible Phenotypes and Multidrug Resistance in Expanded-Spectrum Cephalosporin-Resistant Uropathogenic Escherichia coli from a Multicenter Cohort: Insights into the Phenotypic and Genetic Basis of Coresistance

Antimicrobial resistance in urinary tract infections (UTIs) is a major public health concern. This study aims to characterize the phenotypic and genetic basis of multidrug resistance (MDR) among expanded-spectrum cephalosporin-resistant (ESCR) uropathogenic Escherichia coli (UPEC) causing UTIs in California patient populations. Between February and October 2019, 577 ESCR UPEC isolates were collected from patients at 6 clinical laboratory sites across California. Lineage and antibiotic resistance genes were determined by analysis of whole-genome sequence data. The lineages ST131, ST1193, ST648, and ST69 were predominant, representing 46%, 5.5%, 4.5%, and 4.5% of the collection, respectively. Overall, 527 (91%) isolates had an expanded-spectrum β-lactamase (ESBL) phenotype, with bla CTX-M-15 , bla CTX-M-27 , bla CTX-M-55 , and bla CTX-M-14 being the most prevalent ESBL genes. In the 50 non-ESBL phenotype isolates, 40 (62%) contained bla CMY-2 , which was the predominant plasmid-mediated AmpC (pAmpC) gene. Narrow-spectrum β-lactamases, bla TEM-1B and bla OXA-1 , were also found in 44.9% and 32.1% of isolates, respectively. Among ESCR UPEC isolates, isolates with an ESBL phenotype had a 1.7-times-greater likelihood of being MDR than non-ESBL phenotype isolates (P < 0.001). The cooccurrence of bla CTX-M-15 , bla OXA-1 , and aac(6')-Ib-cr within ESCR UPEC isolates was strongly correlated. Cooccurrence of bla CTX-M-15 , bla OXA-1 , and aac(6')-Ib-cr was associated with an increased risk of nonsusceptibility to piperacillin-tazobactam, cefepime, fluoroquinolones, and amikacin as well as MDR. Multivariate regression revealed the presence of bla CTX-M-55 , bla TEM-1B , and the ST131 genotype as predictors of MDR.

59 BASIC BIOLOGICAL SCIENCES↗

DOE CESER 6 GHz Interference Study

DOE CESER has sponsored Idaho National Laboratory (INL) to conduct an objective and independent study of potential 6 GHz interference from outdoor operation of unlicensed devices in the 6 GHz band on fixed service (FS) microwave communication links operated by electrical sector incumbents in that band. INL is collaborating with University of Notre Dame (UND), Electric Power Research Institute (EPRI), Lockard & White, Southern Company, and AT&T, to gather data with real-world 6 GHz interference experiments and identify (1) the potential for interference from unlicensed devices and (2) the interference necessary to cause harm to the incumbents. In addition to the functional assessment, a security assessment of the FCC mandated Automatic Frequency Coordination (AFC) System to regulate use of unlicensed 6 GHz standard power devices is also being conducted. A major objective is to create a science-based and defensible methodology used to produce the necessary data and to derive objective conclusions. This proven methodology can then be used to produce objective data and conclusions for other spectrum bands with similar incumbent uses including 4.4 – 4.9 GHz and 7.125 – 7.4 GHz, identified in the reconciliation bill that was adopted on July 4, 2025, as well as the National Spectrum Strategy discussions that are ongoing. This report contains 6 GHz field experiments and findings in the following real-world scenarios with commercial unlicensed standard power (SP) 6 GHz devices regulated by Automated Frequency Coordination (AFC): • University of Notre Dame (UND) Stadium with a capacity of 80,000 spectators, where Wi-Fi operating in 6 GHz has been deployed recently • Southern Company 6 GHz FS microwave link between Columbus and Fortson, Georgia Following are the following key findings from this study. 1. The AFC is under-protective of FS when line-of-sight exists along the path centerline. Data collected at Southern’s 6 GHz fixed link site shows significant erosion of as much as 21.4-24.4 dB of under-protection that can lead to potential service degradation under typical operating conditions. This first key finding is most likely the result of erroneous use of the RF propagation model. INL will collaborate with EPRI and the AFC Functional Requirements Working Group to submit a change request to the WinnForum TS-1014 standard towards correct use of the propagation model by the AFC. 2. There is additive interference effect of about 3 dB from nearly equal power interferers measured from simultaneous operation of two SP AP's operating co-channel with the FS receive from different locations along the path. This second key finding should be used to add the impact of additive interference of operation of multiple APs in the same geographical area, to the next generation of AFCs. INL will collaborate with FCC on the need for the AFC to consider additive interference. We also recommend that additional experiments are conducted on 6 GHz spectrum interference to further improve the AFC operation as the number of outdoor Wi-Fi devices continues to increase. These proposed steps and recommendations will make the co-existence of the incumbents and the 6 GHz outdoor Wi-Fi providers possible without any impact on the incumbents with a win-win outcome for all.

6 GHz↗

Observation of the Charmonium Decay η c → γ γ in J / ψ → γ η c

Using ( 2712.4 ± 14.3 ) × 10 6 ψ ( 3686 ) events collected with the BESIII detector at the BEPCII collider, the decay η c → γ γ in J / ψ → γ η c is observed. We determine the product branching fraction B ( J / ψ → γ η c ) × B ( η c → γ γ ) = ( 5.23 ± 0.2 6 stat ± 0.3 0 syst ) × 10 − 6 . This result is consistent with the lattice QCD calculation ( 5.34 ± 0.16 ) × 10 − 6 from HPQCD in 2023. By using the world-average values of B ( J / ψ → γ η c ) and the total decay width of η c , the partial decay width Γ ( η c → γ γ ) is determined to be ( 11.30 ± 0.5 6 stat ± 0.6 6 syst ± 1.1 4 ref ) keV , which deviates from the corresponding world-average value by 3.4 σ . Published by the American Physical Society 2025

Ablikim, M.↗

Partial wave analyses of ψ ( 3686 ) → p p ¯ π 0 and ψ ( 3686 ) → p p ¯ η

Using a sample of ( 2712 ± 14 ) × 10 6 ψ ( 3686 ) events collected with the BESIII detector, we perform partial wave analyses of the decays ψ ( 3686 ) → p p ¯ π 0 and ψ ( 3686 ) → p p ¯ η . The branching fractions of ψ ( 3686 ) → p p ¯ π 0 and ψ ( 3686 ) → p p ¯ η are determined to be ( 133.9 ± 11.2 ± 2.3 ) × 10 − 6 or ( 183.7 ± 13.7 ± 3.2 ) × 10 − 6 and ( 61.5 ± 6.5 ± 1.1 ) × 10 − 6 or ( 84.4 ± 6.9 ± 1.4 ) × 10 − 6 , respectively, where the two solutions are caused by an ambiguous phase angle between resonant and continuum processes. Several well-established N * states are observed in the p π 0 and p η systems, and the corresponding branching fractions are measured. The ratio of decay widths Γ N ( 1535 ) → N η / Γ N ( 1535 ) → N π is determined to be 0.99 ± 0.05 ± 0.19 . Published by the American Physical Society 2025

Ablikim, M.↗

Search for Λ − Λ ¯ oscillation in J / ψ → Λ Λ ¯ decay

Using ( 10087 ± 44 ) × 10 6 J / ψ decays collected by the BESIII detector at the BEPCII collider, we search for baryon number violation via Λ − Λ ¯ oscillation in the decay J / ψ → Λ Λ ¯ . No evidence for Λ − Λ ¯ oscillation is observed. The upper limit on the time-integrated probability of Λ − Λ ¯ oscillation is estimated to be 1.4 × 10 − 6 , corresponding to an oscillation parameter less than 2.1 × 10 − 18 GeV at 90% confidence level. Published by the American Physical Society 2025

Ablikim, M.↗

Measurements of the Branching Fraction, Polarization, and C P Asymmetry for the Decay B 0 → ω ω

We present a comprehensive study of B 0 → ω ω decays using 772 × 10 6 B B ¯ pairs collected with the Belle detector at the KEKB e + e − collider. This process is a suppressed charmless decay into two vector mesons and can exhibit interesting polarization and C P violation. The decay is observed for the first time with a significance of 7.9 standard deviations. We measure a branching fraction B = ( 1.53 ± 0.29 ± 0.17 ) × 10 − 6 , a fraction of longitudinal polarization f L = 0.87 ± 0.13 ± 0.13 , and a time-integrated C P asymmetry A C P = − 0.44 ± 0.43 ± 0.11 , where the first uncertainties listed are statistical and the second are systematic. This is the first observation of B 0 → ω ω and the first measurements of f L and A C P for this decay. Published by the American Physical Society 2024

Physics↗

Enhanced Hanford Low-Activity Waste Glass Property Data Development: Phase 5 and Phase 6

This report summarizes the data collected on two test matrices of low-activity waste (LAW) glass compositions intended to expand the composition-property database: Low-Activity Waste (LAW) Phase 5: Expansion of LAW Glass Composition Boundaries and LAW Phase 6: High PCT and VHT Response Glass Matrix. Both matrix glass compositions were statistically designed to expand the LAW glass composition region. The analyses performed on these glasses include chemical composition (for target compositional verification), density, viscosity, electrical conductivity, crystal fraction, container centerline cooling with crystal identification, the product consistency test (PCT) response, the vapor hydration test (VHT) response, and sulfur solubility. Because of the slightly different scope of the two matrices, not all methods were applied to both matrices. Specifically, the following measurements were taken only on the LAW Phase 5: Expansion of LAW Glass Composition Boundaries glasses: crystal fraction as a function of temperature, density (ρ), viscosity (η), and electrical conductivity (EC, e). Combined, these data contribute a significant amount, 51 glasses, to the database for high LAW loaded enhanced waste glasses. Most of these data are focused near the boundaries of acceptable PCT and VHT responses, where prediction uncertainties are most impactful.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

2021 Results for Avian Monitoring of Inorganic and Organic Element Concentrations in Passerine Eggs and Nestlings Collected from Technical Area 16 Burn Grounds, Technical Area 36 Minie, and Technical Area 39 Point 6 at Los Alamos National Laboratory (Rev. 2)

In 2021, non-viable avian eggs and one nestling were opportunistically collected at Los Alamos National Laboratory (LANL) near open detonation sites located at Technical Area (TA) 16 burn grounds and TA-36 Minie. Similar to previous years, nestboxes were monitored at TA-39 Point 6, however, no avian samples were available for opportunistic collection. Samples were evaluated for inorganic elements (mostly metals), dioxins, and furans. One ash-throated flycatcher (Myiarchus cinerascens) egg sample was collected from TA-16 burn grounds. One ash-throated flycatcher and one mountain bluebird (Sialia currucoides) egg sample and one deceased western bluebird (Sialia mexicana) nestling sample were collected from TA-36 Minie. Concentrations of inorganic elements observed in this study were compared with the regional statistical reference level (RSRL) which is the upper-level bounds of background concentrations (mean + three standard deviations = 99% confidence interval). Several inorganic elements were not detected in avian eggs. Most inorganic elements detected were below the RSRL and all were the lowest observable adverse effect level (LOAEL), when available. The nestling collected from TA-36 did not contain detectable concentrations of dioxin or furan congeners. These data suggest that inorganic and organic element concentrations in eggs and nestlings are not of ecological concern. More data are needed to make a robust assessment and to evaluate trends over time.

54 ENVIRONMENTAL SCIENCES↗

Search for the isospin-violating decays 𝜒 𝑐⁢𝐽 → $Λ\bar{⁢Σ}^0$ + c.c. and 𝜂 𝑐 → $Λ\bar{⁢Σ}^0$ + c.c.

Using a sample of (2712.4 ± 14.3) × 10 6 𝜓⁡(3686) events collected with the BESIII detector, we perform a search for the isospin-violating decays 𝜒 𝑐⁢𝐽 → $Λ\bar{⁢Σ}^0$ + c.c.(𝐽 = 0,1,2) and 𝜂 𝑐 → $Λ\bar{⁢Σ}^0$ + c.c. No significant signal for 𝜒 𝑐⁢𝐽 or 𝜂 𝑐 is observed in the $Λ\bar{⁢Σ}^0$ invariant mass distribution. The upper limits on the branching fractions at the 90% confidence level are set to be ℬ⁡(𝜒 𝑐⁢0 → $Λ\bar{⁢Σ}^0$ + c.c.) < 1.5 × 10 −6 , ℬ⁡(𝜒 𝑐⁢1 → $Λ\bar{⁢Σ}^0$ + c.c.) < 1.6 × 10 −6 , ℬ⁡(𝜒 𝑐⁢2 → $Λ\bar{⁢Σ}^0$ + c.c.) < 1.7 × 10 −6 , and ℬ⁡(𝜂 𝑐 → $Λ\bar{⁢Σ}^0$ + c.c.) < 6.2 × 10 −5 for the first time.

Ablikim, M. [Institute of High Energy Physics] (OR↗

Observation of an Axial-Vector State in the Study of the Decay ψ ( 3686 ) → ϕ η η ′

Using ( 2712.4 ± 14.3 ) × 10 6 ψ ( 3686 ) events collected with the BESIII detector at BEPCII, a partial wave analysis of the decay ψ ( 3686 ) → ϕ η η ′ is performed with the covariant tensor approach. In addition to the established states h 1 ( 1900 ) and ϕ ( 2170 ) , an axial-vector state with a mass near 2.3 GeV / c 2 is observed for the first time. Its mass and width are measured to be 2316 ± 9 stat ± 3 0 syst MeV / c 2 and 89 ± 1 5 stat ± 2 6 syst MeV , respectively. The product branching fractions of B [ ψ ( 3686 ) → X ( 2300 ) η ′ ] B [ X ( 2300 ) → ϕ η ] and B [ ψ ( 3686 ) → X ( 2300 ) η ] B [ X ( 2300 ) → ϕ η ′ ] are determined to be ( 4.8 ± 1.3 stat ± 0.7 syst ) × 10 − 6 and ( 2.2 ± 0.7 stat ± 0.7 syst ) × 10 − 6 , respectively. The branching fraction B [ ψ ( 3686 ) → ϕ η η ′ ] is measured for the first time to be ( 3.14 ± 0.1 7 stat ± 0.2 4 syst ) × 10 − 5 . The first uncertainties are statistical and the second are systematic. Published by the American Physical Society 2025

Ablikim, M.↗

Measurement of branching-fraction ratios and CP asymmetries in B± → DCP±K± decays at Belle and Belle II

Abstract We report results from a study ofB ± → DK ± decays followed byDdecaying to theCP-even final stateK + K − and CP-odd final state$$ {K}_S^0{\pi}^0 $$ K S 0 π 0 , whereDis an admixture ofD 0 and$$ {\overline{D}}^0 $$ D ¯ 0 states. These decays are sensitive to the Cabibbo-Kobayashi-Maskawa unitarity-triangle angleϕ 3 . The results are based on a combined analysis of the final data set of 772×10 6 $$ B\overline{B} $$ B B ¯ pairs collected by the Belle experiment and a data set of 198×10 6 $$ B\overline{B} $$ B B ¯ pairs collected by the Belle II experiment, both in electron-positron collisions at the Υ(4S) resonance. We measure the CP asymmetries to be$$ \mathcal{A} $$ A CP+ = (+12.5±5.8±1.4)% and$$ \mathcal{A} $$ A CP− = (−16.7±5.7±0.6)%, and the ratios of branching fractions to be$$ \mathcal{R} $$ R CP+ = 1.164±0.081±0.036 and$$ \mathcal{R} $$ R CP− = 1.151±0.074±0.019. The first contribution to the uncertainties is statistical, and the second is systematic. The asymmetries$$ \mathcal{A} $$ A CP+ and$$ \mathcal{A} $$ A CP− have similar magnitudes and opposite signs; their difference corresponds to 3.5 standard deviations. From these values we calculate 68.3% confidence intervals of (8.5 ° <ϕ 3 < 16.5 ° ) or (84.5 ° <ϕ 3 < 95.5 ° ) or (163.3 ° <ϕ 3 < 171.5 ° ) and 0.321 B< 0.465.

Physics↗

2020 Results for Avian Monitoring of Inorganic and Organic Element Concentrations in Passerine Eggs and Nestlings Collected from Technical Area 16 Burn Grounds, Technical Area 36 Minie, and Technical Area 39 Point 6 at Los Alamos National Laboratory

In 2020, non-viable avian eggs and two nestling were opportunistically collected at Los Alamos National Laboratory (LANL) near open detonation sites located at Technical Area (TA) 16 burn grounds, TA-36 Minie, and TA-39 Point 6. These samples were evaluated for inorganic elements (mostly metals), dioxins, and furans. A total of six eggs and two deceased western bluebird (Sialia mexicana) nestling samples were collected among the three locations of interest. Concentrations of inorganic elements observed in this study were compared with the regional statistical reference level (RSRL) which is the upper-level bounds of background concentrations (mean + three standard deviations = 99% confidence interval). Several inorganic elements were not detected in avian eggs and all inorganic elements detected were below the RSRL and the lowest observable adverse effect level (LOAEL), when available. One nestling collected from TA-39 contained detectable concentrations of two dioxin congeners. Heptachlorodibenzodioxin-1,2,3,4,6,7,8 and octachlorodibenzodioxin-1,2,3,4,6,7,8,9 concentration exceeded the RSRL, but did not exceed the calculated tetrachlorodibenzodioxin 2,3,7,8 (TCDD) toxic equivalent LOAEL. These data suggest that inorganic and organic element concentrations in eggs and nestlings are not of ecological concern. More data are needed to make a robust assessment and to evaluate trends over time.

54 ENVIRONMENTAL SCIENCES↗