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Annual Statewide Toxics Summary
Cobalt
FAQs
nanograms per cubic meter
Year
Months
Present
Minimum
Median
Mean
90th
Percentile
Maximum
Standard
Deviation
Number of
Observations
Detection
Limit
2024
0.65
0.65
*
0.65
2.8
0.26
154
1.3
2023
0.65
0.65
0.71
0.65
4.0
0.30
362
1.3
2022
0.65
0.65
0.76
0.65
4.2
0.44
390
1.3
2021
0.65
0.65
*
0.65
4.4
0.53
312
1.3
2020
0.65
0.65
*
0.65
1.6
0.09
106
1.3
2019
0.65
0.65
0.84
1.6
2.8
0.46
410
1.3
2018
0.65
0.65
0.92
1.7
3.4
0.53
428
1.3
2017
0.65
0.65
1.41
2.8
5.6
1.02
420
1.3
2016
0.65
0.65
0.69
0.65
3.0
0.21
424
1.3
2015
0.65
0.65
0.65
0.65
1.6
0.05
418
1.3
2014
0.8
0.8
1.03
1.8
4.5
0.66
398
1.6
2013
0.75
0.75
*
0.75
2.7
0.19
431
1.5
2012
0.75
0.75
0.92
0.75
4.0
0.53
444
1.5
2011
0.75
0.75
0.76
0.75
4.4
0.19
430
1.5
2010
0.75
0.75
0.76
0.75
2.0
0.09
440
1.5
2009
0.75
0.75
0.84
0.75
8.0
0.72
520
1.5
2008
*
*
*
*
*
*
0
*
2007
0.75
0.75
0.88
0.75
6.7
0.75
462
1.5
2006
*
*
*
*
*
*
0
*
2005
*
*
*
*
*
*
0
*
2004
*
*
*
*
*
*
0
*
2003
7.5
7.5
*
7.5
7.5
0.00
86
15
2002
7.5
7.5
7.77
7.5
20
0.61
491
15
2001
8
8
8.14
8
40
1.76
505
16
2000
8
8
8.12
8
26
1.16
472
16
1999
8
8
8.23
8
25
1.70
565
16
1998
8
8
8.02
8
18
0.42
561
16
1997
8
8
8.03
8
23
0.74
557
16
1996
8
8
8.00
8
8
0.00
595
16
1995
8
8
8.13
8
38
1.56
602
16
1994
8
8
8.15
8
33
1.46
585
16
1993
8
8
8.00
8
8
0.00
575
16
1992
8
8
8.01
8
17
0.38
554
16
1991
8
8
8.02
8
19
0.46
567
16
1990
8
8
*
8
17
0.51
309
16
1989
*
*
*
*
*
*
0
*
Notes
:
Values below the Limit of Detection (LoD) assumed to be ½ LoD.
Means and risks shown only for years with data in all 12 months.
"*" means there was insufficient or no data available to determine the value.
