Archives of Environmental Contamination and Toxicology (2021) 81:236–254

Overview

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et al. 2005; Bauch 2007; May and Brumbaugh 2007; Schmitt by humans. Table 1 presents a summary of the sampling
Table 1 Fish plug evaluation study design summary
wet weight of the tissue sample. The laboratory’s method material sample (see Table 3 for the required frequencies
The required quality control samples associated with Table 3, the selenium analysis laboratory ran three additional
reference material sample (see Table 2 for the required fre- the tissue sample. However, because the USEPA selenium
noted in Table 2, the mercury analysis laboratory ran an using a separate sample aliquot (i.e., a single plug from each
Table 2 QC samples and acceptance criteria for mercury analysis of fish tissue
samples, with analyses interspersed among Less than one-tenth the concentration of an Overall, 60% of the method blanks were non-
the samples in the analysis batch associated sample detects (below 40 pg), and 40% of the method
of any field samples, and again at the end of ranged from 80 to 119% overall
Reference material sample (laboratory used 1 per batch of up to 20 field samples 75–125% recovery None of the reference sample results fell out-
TORT-3 from the National Research Council side the acceptance limits. Recoveries ranged
of Canada) from 88 to 105% overall
Matrix spike sample 1 per batch of up to 20 homogenized fillet tis- 70–130% recovery None of the matrix spike sample results
run two matrix spike samples per batch) Recoveries ranged from 71 to 119% overall
ranged from 92 to 108% overall sample. Summary statistics were generated and tabulated
75–125% recovery None of the reference sample results fell out- tions; selenium wet-weight concentrations and dry-weight
from 90 to 110% overall
Recoveries ranged from 72 to 106% overall let) and for each combination of tissue collection method,
Table 3 QC samples and acceptance criteria for selenium analysis of fish tissue
in Supplementary Information Table SI1. Results and measures were observed for the Lake Ontario Chinook
are summarized in Table 4 across all of the sampling loca- approximately 8.5%. The concentrations from this site/
let). Table 5 summarizes the mercury results within each sites/species, indicating that the variability in concentra-
Potomac River Largemouth Bass, and lower mean con- tistically significant at an alpha of 0.05 (p = 0.973); therefore,
in this study range from 23 to 649 ng/g, which is well of waterbody and species, and a single overall comparison
Lake Fish Tissue Study ranged from 23 ng/g to a maxi- ate from a normal distribution slightly (Shapiro–Wilk
ment ranged from 21 to 1,418 ng/g (USEPA 2016b), and results. Model variability did not vary with the measured
Coastal Condition Assessment ranged from 23 to 956 ng/g model residuals and measured concentrations), and Levene’s
samples represent a range of mercury concentrations that between sample types (p = 0.795) (Levene et al. 1960). As
Mean mercury concentrations in the fillet plugs (FP) p < 0.0001 when comparing model variability across water-
concentrations for FP samples) (Table 5 and Fig. 4). The data would have made statistical significance of sample type
Supplementary Information Table SI2. Descriptive statistics
Table 4 Descriptive statistics for mercury results across all sampling locations by sample type
for the 240 selenium sample results are detailed in Table 6
(Table 7) (Fig. 6). Wet-weight selenium results ranged from
results, evidenced by the RSD values in Table 7, was less
specific RSD for wet-weight selenium was about 16% versus
over 80% for mercury.
Table 5 Descriptive statistics for mercury results by sampling location, species, and sample type
selenium concentrations (Table 7 and Fig. 8). There was
Fig. 4 Mean natural log-transformed mercury wet-weight results by species and sample type
Fig. 5 Mean natural log-transformed mercury wet-weight results by in Fig. 10. As with the selenium results, the log-transformed

Methods (brief)

and Selenium: Fish Muscle Biopsy Samples Versus Homogenized
mercury phase included 300 fillet homogenates and 300 field-extracted plug samples from 60 fish, and the selenium phase
fillet samples provide sufficient tissue mass for the analysis Study Objectives and Sampling Design
Researchers have considered other tissue collection meth- began collecting fish muscle biopsy plug samples (fillet
extraction of muscle tissue (i.e., 40-mg samples) from live ing and homogenizing fish to obtain mercury data. At that
technique for taking skeletal muscle samples from live adult fillet plug analysis could serve as a reliable alternative to
using a dermal biopsy punch to collect a 1-cm3 tissue sample whole fillet tissue to monitor mercury concentrations in
fillet plug) samples to analyze selenium levels in the endan- plug samples for selenium surveillance monitoring in fresh-
son et al. (2000) collected fillet plugs from the endangered Act Section 304(a) aquatic life ambient water quality crite-
samples to assess mercury levels in endangered Colorado objectives of this study were to assess the comparability of
The choice of tissue sample type for contaminant analysis homogenized fillet samples and to test the applicability of
Knight et al. (2019) noted that this sampling alternative has extracted fillet plug samples for the selenium phase (plus an
not been widely implemented in routine monitoring due, at additional 120 fillet plug samples for solids determination).
whether the small sample volumes and the tissue extraction
Sampling sites and fish species collected 6 6 Lake Michigan, Lake Trout; Lake Erie, Walleye; Lake
Fish collected per site 10 5 Collection of single specimen fish samples per site
Fish tissue sample types 2 2 Fillet plug samples (two plugs per sample) and homog-
enized fillet tissue samples

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Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.

Commit	Date	Change	Description
b01ec52c	2026-08-04	major	2 sections added
d49e450f	2026-08-03	major	5 sections added; narrative text revised