Fourth Sampling Period

The table below shows the radioactive isotopes measured in each of the kelp samples, corrected to time of collection during the fourth sampling period (May through June 2015). To date, all of the samples have been analyzed and are shown in the table. All data is based on a single sample size (n=1) of 6.5 kg fresh weight of blade tissue.

For a discussion of the radioactive isotopes shown in the table below, please see Results from First Sampling Period.


Sample ID Location
UAS-4
Juneau, AK
KSMSC-4
Kodiak Island, AK
RES-5
Tofino, BC
DC-5
Bamfield, BC
RRU-4
Sooke, BC
ODFW-4a
Depoe Bay, OR
ODFW-4c
Gregory Point Research Reserve, OR
ODFW-4d
Cape Arago, OR
ODFW-4b
Redfish Rocks Marine Reserve, OR
HSU-4
Humboldt County, CA
BML-4
Van Damme State Park, CA
Anthropogenic Natural
Collection Date Cs-137 Cs-134 I-131 K-40 U-238 series (early) U-238 series (late) Th-232 series (early) Th-232 series (late) Be-7
05/14/2015
0.19 ± 0.04
nondetect (< 0.04)
nondetect (< 1.6)
4320 ± 4
171.5 ± 4.9
2.47 ± 0.03
1.06 ± 0.16
0.24 ± 0.02
2.1 ± 0.5
05/31/2015
0.20 ± 0.02
nondetect (< 0.02)
nondetect (< 0.2)
3525 ± 2
48.9 ± 1.5
1.62 ± 0.03
0.18 ± 0.09
0.06 ± 0.01
0.8 ± 0.2
05/28/2015
0.30 ± 0.04
nondetect (< 0.04)
nondetect (< 4)
3112 ± 4
132.4 ± 6
1.9 ± 0.05
0.68 ± 0.16
0.21 ± 0.02
4.4 ±
05/16/2015
0.23 ± 0.02
nondetect (< 0.02)
nondetect (< 0.5)
2772 ± 2
52.2 ± 1.9
1.74 ± 0.03
0.55 ± 0.08
0.08 ± 0.01
7.4 ± 0.3
06/13/2015
0.15 ± 0.04
nondetect (< 0.04)
nondetect (< 0.5)
3791 ± 5
31.4 ± 3
1.47 ± 0.05
0.46 ± 0.15
0.12 ± 0.02
1.4 ± 0.6
05/04/2015
0.23 ± 0.03
nondetect (< 0.02)
nondetect (< 0.6)
3570 ± 3
18.5 ± 2.3
1.89 ± 0.03
0.82 ± 0.11
0.06 ± 0.01
0.9 ± 0.4
05/18/2015
0.23 ± 0.05
nondetect (< 0.04)
nondetect (< 4.4)
3156 ± 4
80.3 ± 6.4
1.69 ± 0.06
0.83 ± 0.18
0.04 ± 0.01
0.7 ± 0.4
05/31/2015
0.21 ± 0.05
nondetect (< 0.05)
nondetect (< 2.5)
2837 ± 6
68.9 ± 5.7
2.05 ± 0.07
nondetect (< 0.21)
0.15 ± 0.03
nondetect (< 0.7)
05/21/2015
0.14 ± 0.04
nondetect (< 0.04)
nondetect (< 3.9)
3973 ± 4
96.5 ± 6.4
1.07 ± 0.05
nondetect (< 0.14)
0.16 ± 0.02
nondetect (< 0.6)
06/10/2015
nondetect (< 0.05)
nondetect (< 0.06)
nondetect (< 1.1)
4543 ± 8
33.6 ± 5.4
1.56 ± 0.07
0.83 ± 0.27
0.11 ± 0.02
1.5 ± 0.8
06/18/2015
0.21 ± 0.03
nondetect (< 0.03)
nondetect (< 2.9)
2372 ± 4
111.0 ± 5
2.16 ± 0.05
1.2 ± 0.2
0.44 ± 0.03
4.1 ± 0.9

Table Notes:

  • All uncertainties quoted are "one-sigma," meaning that they represent a 68% confidence range for the quantity measured. Detection limits are also "one-sigma" in that they give the 68% confidence upper limit.
  • Radioactive isotopes are measured in units of Becquerels per kilogram dry weight (Bq/kg dwt). One Becquerel is one nuclear decay per second.
  • Data are decay-corrected to the date the sample was collected.


Update Log:

  • 12/08/2015 - Initial data posted
  • 05/18/2016 - Sample BML-4 posted