Transcript Our waters, our fish, our people”

“Our waters, our fish, our
people”
Mercury contamination in fish
resources of two Treaty #3
communities
Research Question
• Do our fish still contain high levels of Hg?
• Is it possible that some fish species in
some lakes are clean enough to eat?
• How much fish can we eat without the fear
of Hg poisoning?
• Can we set up a monitoring program
ourselves to check the Hg levels in fish?
Grassy Narrows Territory
Wabaseemoong Territory
Clay Lake
Winnipeg River
Ball Lake
Caribou River
Maynard Lake
Tetu Lake
Indian Lake
Swan Lake
Separation Lake
Old Man Lake
Tide Lake
Goshawk Lake
Garden Lake
Walleye
7.000
6.000
Ball lake
Clay lake
5.000
Garden
Indian lake
Maynard lake
4.000
Separation
Tide lake
3.000
Ball Lake trendline
2.000
1.000
0.000
20
30
40
50
60
length (cm)
70
80
90
Whitefish
0.600
0.500
Ball lake
Clay lake
Clay Lake Trendline
Garden lake
0.400
Indian lake
Maynard lake
Separation lake
Tide lake
0.300
0.200
0.100
0.000
35
40
45
50
length (cm)
55
60
Bass
7.000
6.000
Ball lake
5.000
Clay lake
Indian lake
Maynard lake
Separation lake
4.000
Clay Lake Trendline
3.000
2.000
1.000
0.000
15
20
25
30
35
length (cm)
40
45
50
Northern Pike
7.000
6.000
Ball lake
Clay lake
5.000
Indian lake
Garden lake
Separation lake
4.000
Tide lake
Maynard
3.000
Clay Lake Trendline
2.000
1.000
0.000
30
40
50
60
70
length (cm)
80
90
100
110
Hg in Clay Lake
Scott (1974)
Species
Walleye
Northern
Pike
Whitefish
Present study (2003)
N
Avg Hg
(mg/kg)
length
range(cm)
N
Avg Hg
(mg/kg)
Length
range(cm)
508
7.10
15.3-71.1
20
2.98
28.0-69.0
497
5.97
21.2-80.3
20
2.14
39.0-68.0
234
1.83
25.7-52.5
19
0.31
44.0-54.0
Hg in Walleye from Ball Lake
N
Hg (mg/kg)
1971
60
1.99
1972
45
2.71
1976
46
1.39
Present study
(2003)
20
0.40
Year
Mercury Contamination in Walleye
Concentraton Hg (ug/g)
18
16
Clay Lake
14
12
10
1973
2003
8
6
Ball Lake
4
Clay Lake
Indian Lake
2
Indian Lake
Ball Lake
Tetu Lake
0
0
20
40
60
80
100
120
distance downstream from Dryden (miles)
140
160
180
200
Table 20: Average Hg Levels Fishing Popularity of Specific Lakes
Grassy Narrows
Lake
Average Level of
Hg
# Participants
Fishing (% of
Population)
Clay
2.982
7 (13%)
Ball
1.070
18 (34%)
Tide
0.979
24 (45%)
Indian
0.643
36 (68%)
Seperation
0.600
39 (74%)
Garden
0.575
45 (85%)
Maynard
0.417
47 (89%)
Table 1: Participant Profile of Each Community
Grassy Narrows
GN %
Wabaseemoong
WD %
Total n
87
100%
55
100%
Sampled
52
60%
41
75%
Volunteered
35
40%
14
25%
Male
51
59%
21
38%
Female
36
41%
34
62%
18-40
55
63%
35
64%
41-60
21
24%
16
29%
61+
11
13%
4
7%
Distribution of Average Fish Intake – Grassy Narrows
30.00
25.00
# 0f Participants
20.00
15.00
10.00
5.00
0.00
0-4
5-9
10-19
20-39
40-59
60-79
Average Total Fish (g/day)
80-99
100-199
200-299
Table 20: Average portion size for a fish meal (g/meal) (mean ± SD)
Grassy Narrows
Walleye
276 ± 134
Whitefish
232 ± 167
Bass
255 ± 192
Northern Pike
180 ± 145
Average Fish Intake - Grassy Narrows By Gender
Group
Local Fish
Market Fish
60.00
Average Intake (g of fish/day)
50.00
40.00
30.00
20.00
10.00
0.00
Male
Female
Average
Male
Female
Summer
Male
Female
Fall
Season
Male
Female
Winter
Male
Female
Spring
Average Fish Intake - Grassy Narrows By
Age Group
Local Fish
Market Fish
60.00
Average Intake (g of fish/day)
50.00
40.00
30.00
20.00
10.00
0.00
18-40 41-60 60+
18-40 41-60 60+
18-40 41-60 60+
18-40 41-60 60+
18-40 41-60 60+
Average
Summer
Fall
Winter
Spring
Season
Average Mercury Exposure by Age and Gender Group – Grassy Narrows
0.7
Average Mercury Exposure (ug/kg body wt/day)
0.6
0.5
0.4
female
male
0.3
0.2
0.1
0
18-40
41-60
61+
Mean Hair Hg (ppm)
7.001-8.00
6.001-7.00
5.001-6.00
4.001-5.00
3.001-4.00
2.001-3.00
1.001-2.00
DL-1.00
below DL
# of Participants
Distribution of Mean Hair Mercury
Concentrations – Grassy Narrows
30
25
20
15
10
5
0
Estimated Mercury Exposure and Measured
Hair Level - Grassy Narrows
8
7
6
Hair (ppm)
5
4
3
2
1
0
0
0.5
1
1.5
Intake (ug Hg/kg body wt/day)
2
2.5
Profile of participants with high Hg intake in Grassy Narrow
Estimated Hg
Exposure
(ug/kg body
wt/ day)
Mean Hair
Hg (ppm)
Age
Gender
Average Fish
Consumption
(g/day)
GN104
7.2
52
Male
10
0.3
GN118
7.4
49
Male
276
0.7
Participant
Recommendation
Grassy Narrow
• Currently, there is no problem with high Hg
exposure from eating fish
• Do not eat fish from Clay and Ball Lake
• Promote eating more fish, particularly
whitefish up to 5 fish meal per week
• Walleye may be limited to 2 fish meal
every 3 weeks for those who are
concerned.