. Author manuscript; available in PMC: 2019 Jan 1.

Published in final edited form as: Neurotoxicology. 2017 Jun 23;64:50–59. doi: 10.1016/j.neuro.2017.06.011

Table 1.

Summary statistics for demographics (I), exposure metrics, and blood metals (II) in welders and controls.

	Controls (N=32) Mean ± SD	Welders (N=48) Mean ± SD	Raw p-values
*I. Demographics*
Age (years)	43.4 ± 11.2	48.0 ± 10.8	0.075
Education (years)	16.2 ± 2.4	12.8 ± 1.7	<0.001
ALT (IU/L)	37.7 ± 16.5	39.8 ± 16.7	0.684
BMI (kg/m²)	26.0 ± 3.3	29.2 ± 5.3	0.004
Hemoglobin	14.8 ± 0.8	15.2 ± 1.0	0.102
Smokers (%)	3.2%	15.2%	0.091
Cigarettes/day (no.)	13.0 ± 12.0	20.2 ± 13.5	0.303
UPDRS-I	1.0 ± 1.9	1.7 ± 2.0	0.125
UPDRS-II	3.9 ± 3.1	4.6 ± 3.5	0.383
UPDRS-III	1.5 ± 2.1	1.9 ± 2.4	0.461

*II. Exposure metrics and Blood Metal levels*
HrsW (hours)	0 ± 0 (0)	248 ± 195	<0.001
E₉₀ mg-days/m³	0.0027 ± 0	2.4 ± 2.0	<0.001
YrsW (years)	0 ± 0 (0)	25.8 ± 10.6	<0.001
ELT mg-years/m³	0.0013 ± 0.0004	1.2± 0.8	<0.001
Mn (ng/mL)	8.8 ± 2.5	10.7 ± 3.2	<0.001
Fe (μg/mL)	498 ± 75	551 ± 56	<0.001

Data represent the mean ± SD. Demographic (I) and blood metal (II) measures were compared between controls and welders using analysis of variance (ANOVA) for demographic and blood metal data. Abbreviations: ALT-alanine aminotransferase; BMI-body mass index; UPDRS-Unified Parkinson’s Disease Rating Scale-motor scores.