TY - JOUR
T1 - Blood manganese as an exposure biomarker
T2 - State of the evidence
AU - Baker, Marissa G.
AU - Simpson, Christopher D.
AU - Stover, Bert
AU - Sheppard, Lianne
AU - Checkoway, Harvey
AU - Racette, Brad A.
AU - Seixas, Noah S.
PY - 2014/4/1
Y1 - 2014/4/1
N2 - Despite evidence of adverse health effects resulting from exposure to manganese (Mn), biomarkers of exposure are poorly understood. To enhance understanding, mean blood Mn (MnB) and mean air Mn (MnA) were extracted from 63 exposure groups in 24 published papers, and the relationship was modeled using segmented regression. On a log/log scale, a positive association between MnA and MnB was observed among studies reporting MnA concentrations above about 10 μg/m3, although interpretation is limited by largely cross-sectional data, study design variability, and differences in exposure monitoring methods. Based on the results of the segmented regression, we hypothesize that below the concentration of about 10 μg/m3, Mn in the body is dominated by dietary Mn, and additional inhaled Mn only causes negligible changes in Mn levels unless the inhaled amount is substantial. However, stronger study designs are required to account for temporal characteristics of the MnA to MnB relationships that reflect the underlying physiology and toxicokinetics of Mn uptake and distribution. Thus, we present an inception cohort study design we have conducted among apprentice welders, and the analytical strengths this study design offers. To determine if blood could be a useful biomarker for Mn to be utilized by industrial hygienists in general industry requires additional time-specific analyses, which our inception cohort study design will allow.
AB - Despite evidence of adverse health effects resulting from exposure to manganese (Mn), biomarkers of exposure are poorly understood. To enhance understanding, mean blood Mn (MnB) and mean air Mn (MnA) were extracted from 63 exposure groups in 24 published papers, and the relationship was modeled using segmented regression. On a log/log scale, a positive association between MnA and MnB was observed among studies reporting MnA concentrations above about 10 μg/m3, although interpretation is limited by largely cross-sectional data, study design variability, and differences in exposure monitoring methods. Based on the results of the segmented regression, we hypothesize that below the concentration of about 10 μg/m3, Mn in the body is dominated by dietary Mn, and additional inhaled Mn only causes negligible changes in Mn levels unless the inhaled amount is substantial. However, stronger study designs are required to account for temporal characteristics of the MnA to MnB relationships that reflect the underlying physiology and toxicokinetics of Mn uptake and distribution. Thus, we present an inception cohort study design we have conducted among apprentice welders, and the analytical strengths this study design offers. To determine if blood could be a useful biomarker for Mn to be utilized by industrial hygienists in general industry requires additional time-specific analyses, which our inception cohort study design will allow.
KW - Biomarkers of exposure
KW - exposure assessment
KW - manganese
KW - occupational health
KW - welding
UR - http://www.scopus.com/inward/record.url?scp=84897728031&partnerID=8YFLogxK
U2 - 10.1080/15459624.2013.852280
DO - 10.1080/15459624.2013.852280
M3 - Article
C2 - 24579750
AN - SCOPUS:84897728031
SN - 1545-9624
VL - 11
SP - 210
EP - 217
JO - Journal of Occupational and Environmental Hygiene
JF - Journal of Occupational and Environmental Hygiene
IS - 4
ER -