PMID- 35292021
OWN - NLM
STAT- MEDLINE
DCOM- 20220504
LR  - 20220504
IS  - 1476-069X (Electronic)
IS  - 1476-069X (Linking)
VI  - 21
IP  - 1
DP  - 2022 Mar 16
TI  - Past mercury exposure and current symptoms of nervous system dysfunction in 
      adults of a First Nation community (Canada).
PG  - 34
LID - 10.1186/s12940-022-00838-y [doi]
LID - 34
AB  - BACKGROUND: The watershed in Asubpeeschoseewagong Netum Anishinabek (Grassy 
      Narrows First Nation) territory has been contaminated by mercury (Hg) since 1962, 
      resulting in very high Hg concentrations in fish, central to the community's 
      culture, traditions, economy and diet. Biomarkers of Hg exposure (umbilical cord 
      blood and hair/blood samples), monitored between 1970 and 1997, decreased over 
      time. A recent Grassy Narrows Community Health Assessment (GN-CHA) survey 
      included current symptoms of nervous system dysfunction. The present study aimed 
      to cluster self-reported symptoms and examine their associations with past Hg 
      exposure. METHODS: The GN-CHA included 391 adults. Symptom clustering used a 
      two-step segmentation approach. Umbilical cord Hg and/or yearly measurements of 
      equivalent hair Hg were available for 242 participants. Structural Equation 
      Models (SEM) displayed the associations between Hg exposure and clusters, with Hg 
      exposure modelled as a latent variable or in separate variables (prenatal, 
      childhood and having had hair Hg >/= 5 mug/g at least once over the sampling 
      period). Longitudinal Mixed Effects Models (LMEM) served to examine past hair Hg 
      with respect to clusters. RESULTS: A total of 37 symptoms bonded into 6 clusters, 
      representing Extrapyramidal impairment, Sensory impairment, Cranial nerve 
      disturbances, Gross motor impairment, Neuro-cognitive deficits and Affect/Mood 
      disorders. Median Hg concentrations were 5 mug/L (1-78.5) and 1.1 mug/g (0.2-16) 
      for umbilical cord and childhood hair, respectively. More than one-third (36.6%) 
      had hair Hg >/= 5 mug/g at least once. In SEM, latent Hg was directly associated 
      with Extrapyramidal and Sensory impairment, Cranial nerve disturbances and 
      Affect/Mood disorders. Direct associations were observed for prenatal exposure 
      with Affect/Mood disorders, for childhood exposure with Extrapyramidal impairment 
      and Cranial nerve disturbances, and for hair Hg >/= 5 mug/g with Extrapyramidal and 
      Sensory impairment. For all clusters, a further association between past Hg 
      exposure and symptom clusters was mediated by diagnosed nervous system disorders. 
      LMEM showed higher past hair Hg among those with higher scores for all clusters, 
      except Affect/Mood disorders. CONCLUSION: Our findings provide evidence that in 
      this First Nation community, past Hg exposure from fish consumption was 
      associated with later-life clusters of coexisting symptoms of nervous system 
      dysfunction.
CI  - (c) 2022. The Author(s).
FAU - Philibert, Aline
AU  - Philibert A
AD  - Universite du Quebec a Montreal, Centre de recherche interdisciplinaire sur le 
      bien-etre, la sante, la societe et l'environnement (Cinbiose), CP 8888, Succ. 
      Centreville, Montreal, Quebec, H3C 3P8, Canada.
FAU - Fillion, Myriam
AU  - Fillion M
AD  - Universite du Quebec a Montreal, Centre de recherche interdisciplinaire sur le 
      bien-etre, la sante, la societe et l'environnement (Cinbiose), CP 8888, Succ. 
      Centreville, Montreal, Quebec, H3C 3P8, Canada.
AD  - Departement Science et Technologie, Universite TELUQ, 5800 Saint Denis St, 
      Montreal, Quebec, H2S 3L4, Canada.
FAU - Da Silva, Judy
AU  - Da Silva J
AD  - Grassy Narrows First Nation, General Delivery, P0X 1B0, Grassy Narrows, Ontario, 
      Canada.
FAU - Lena, Tanya Suvendrini
AU  - Lena TS
AD  - Women's College Hospital, 76 Grenville St, Toronto, Ontario, M5S 1B2, Canada.
FAU - Mergler, Donna
AU  - Mergler D
AUID- ORCID: 0000-0002-5205-5180
AD  - Universite du Quebec a Montreal, Centre de recherche interdisciplinaire sur le 
      bien-etre, la sante, la societe et l'environnement (Cinbiose), CP 8888, Succ. 
      Centreville, Montreal, Quebec, H3C 3P8, Canada. mergler.donna@uqam.ca.
LA  - eng
GR  - 152882/CIHR/Canada
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20220316
PL  - England
TA  - Environ Health
JT  - Environmental health : a global access science source
JID - 101147645
RN  - FXS1BY2PGL (Mercury)
SB  - IM
MH  - Animals
MH  - Canada
MH  - Child
MH  - Environmental Exposure/analysis
MH  - Female
MH  - Fishes
MH  - Hair/chemistry
MH  - Humans
MH  - *Mercury
MH  - Nervous System
MH  - Pregnancy
PMC - PMC8925187
OTO - NOTNLM
OT  - Clustering
OT  - First nation
OT  - Mercury
OT  - Mixed effects model
OT  - Nervous system dysfunction
OT  - Past exposure
OT  - Structural equation modelling
OT  - Symptom clusters
COIS- The authors declare that they have no competing interests.
EDAT- 2022/03/17 06:00
MHDA- 2022/05/06 06:00
PMCR- 2022/03/16
CRDT- 2022/03/16 05:41
PHST- 2021/10/01 00:00 [received]
PHST- 2022/02/08 00:00 [accepted]
PHST- 2022/03/16 05:41 [entrez]
PHST- 2022/03/17 06:00 [pubmed]
PHST- 2022/05/06 06:00 [medline]
PHST- 2022/03/16 00:00 [pmc-release]
AID - 10.1186/s12940-022-00838-y [pii]
AID - 838 [pii]
AID - 10.1186/s12940-022-00838-y [doi]
PST - epublish
SO  - Environ Health. 2022 Mar 16;21(1):34. doi: 10.1186/s12940-022-00838-y.