OBJECTIVES: Exposure to manganese (Mn) may cause movement disorders, but less is known whether the effects persist after the termination of exposure. This study investigated the association between former exposure to Mn and fine motor deficits in elderly men from an industrial area with steel production. METHODS: Data on the occupational history and fine motor tests were obtained from the second follow-up of the prospective Heinz Nixdorf Recall Study (2011-2014). The study population included 1232 men (median age 68 years). Mn in blood (MnB) was determined in archived samples (2000-2003). The association between Mn exposure (working as welder or in other at-risk occupations, cumulative exposure to inhalable Mn, MnB) with various motor functions (errors in line tracing, steadiness, or aiming and tapping hits) was investigated with Poisson and logistic regression, adjusted for iron status and other covariates. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated for substantially impaired dexterity (errors >90th percentile, tapping hits <10th percentile). RESULTS: The median of cumulative exposure to inhalable Mn was 58 µg m-3 years in 322 men who ever worked in at-risk occupations. Although we observed a partly better motor performance of exposed workers at group level, we found fewer tapping hits in men with cumulative Mn exposure >184.8 µg m-3 years (OR 2.15, 95% CI 1.17-3.94). MnB ≥ 15 µg l-1, serum ferritin ≥ 400 µg l-1, and gamma-glutamyl transferase ≥74 U l-1 were associated with a greater number of errors in line tracing. CONCLUSIONS: We found evidence that exposure to inhalable Mn may carry a risk for dexterity deficits. Whether these deficits can be exclusively attributed to Mn remains to be elucidated, as airborne Mn is strongly correlated with iron in metal fumes, and high ferritin was also associated with errors in line tracing. Furthermore, hand training effects must be taken into account when testing for fine motor skills.
OBJECTIVES: Exposure to manganese (Mn) may cause movement disorders, but less is known whether the effects persist after the termination of exposure. This study investigated the association between former exposure to Mn and fine motor deficits in elderly men from an industrial area with steel production. METHODS: Data on the occupational history and fine motor tests were obtained from the second follow-up of the prospective Heinz Nixdorf Recall Study (2011-2014). The study population included 1232 men (median age 68 years). Mn in blood (MnB) was determined in archived samples (2000-2003). The association between Mn exposure (working as welder or in other at-risk occupations, cumulative exposure to inhalable Mn, MnB) with various motor functions (errors in line tracing, steadiness, or aiming and tapping hits) was investigated with Poisson and logistic regression, adjusted for iron status and other covariates. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated for substantially impaired dexterity (errors >90th percentile, tapping hits <10th percentile). RESULTS: The median of cumulative exposure to inhalable Mn was 58 µg m-3 years in 322 men who ever worked in at-risk occupations. Although we observed a partly better motor performance of exposed workers at group level, we found fewer tapping hits in men with cumulative Mn exposure >184.8 µg m-3 years (OR 2.15, 95% CI 1.17-3.94). MnB ≥ 15 µg l-1, serum ferritin ≥ 400 µg l-1, and gamma-glutamyl transferase ≥74 U l-1 were associated with a greater number of errors in line tracing. CONCLUSIONS: We found evidence that exposure to inhalable Mn may carry a risk for dexterity deficits. Whether these deficits can be exclusively attributed to Mn remains to be elucidated, as airborne Mn is strongly correlated with iron in metal fumes, and high ferritin was also associated with errors in line tracing. Furthermore, hand training effects must be taken into account when testing for fine motor skills.
Authors: Y Kim; K S Kim; J S Yang; I J Park; E Kim; Y Jin; K R Kwon; K H Chang; J W Kim; S H Park; H S Lim; H K Cheong; Y C Shin; J Park; Y Moon Journal: Neurotoxicology Date: 1999-12 Impact factor: 4.294
Authors: C M Fored; J P Fryzek; L Brandt; G Nise; B Sjögren; J K McLaughlin; W J Blot; A Ekbom Journal: Occup Environ Med Date: 2006-02 Impact factor: 4.402
Authors: R Lucchini; L Selis; D Folli; P Apostoli; A Mutti; O Vanoni; A Iregren; L Alessio Journal: Scand J Work Environ Health Date: 1995-04 Impact factor: 5.024
Authors: Brad A Racette; Susan Searles Nielsen; Susan R Criswell; Lianne Sheppard; Noah Seixas; Mark N Warden; Harvey Checkoway Journal: Neurology Date: 2016-12-28 Impact factor: 9.910
Authors: Danelle Rolle-McFarland; Yingzi Liu; Farshad Mostafaei; S Elizabeth Zauber; Yuanzhong Zhou; Yan Li; Quiyan Fan; Wei Zheng; Linda H Nie; Ellen M Wells Journal: Neurotoxicology Date: 2021-12-10 Impact factor: 4.294
Authors: Anne Lotz; Beate Pesch; Swaantje Casjens; Martin Lehnert; Wolfgang Zschiesche; Dirk Taeger; Chien-Lin Yeh; Tobias Weiss; Tobias Schmidt-Wilcke; Clara Quetscher; Stefan Gabriel; Maria Angela Samis Zella; Dirk Woitalla; Ulrike Dydak; Christoph van Thriel; Thomas Brüning; Thomas Behrens Journal: Neurotoxicology Date: 2020-12-07 Impact factor: 4.398
Authors: Beate Pesch; Swaantje Casjens; Dirk Woitalla; Shalmali Dharmadhikari; David A Edmondson; Maria Angela Samis Zella; Martin Lehnert; Anne Lotz; Lennard Herrmann; Siegfried Muhlack; Peter Kraus; Chien-Lin Yeh; Benjamin Glaubitz; Tobias Schmidt-Wilcke; Ralf Gold; Christoph van Thriel; Thomas Brüning; Lars Tönges; Ulrike Dydak Journal: Cells Date: 2019-01-29 Impact factor: 6.600