Cardiovascular effects after pulmonary exposure to welding fume.
Kan-H; Antonini-JM; Roberts-JR; Salmen-R; Lin-Y; Kashon-ML; Castranova-V
Toxicologist 2012 Mar; 126(Suppl 1):323
Epidemiological studies have found positive associations between air pollution and adverse cardiovascular outcome. Whether exposure to welding fumes cause similar cardiovascular dysfunction remains unclear. The present study investigated the effects of manual metal arc-hard surfacing (MMA-HS) on the heart and the vascular system. Rats were intratracheally instilled with MMA-HS (2 mg/rat, once a week) or saline for seven weeks. On days 1 and 7 after the last treatment, rats were implanted with indwelling catheters and cardiovascular function in response to increasing levels of adrenoreceptor agonists was assessed. Pulmonary exposure to MMA-HS decreased the basal level of left ventricular pressure and the positive dp/dt of the heart at 1 day post-exposure. The negative dp/dt of the heart in response to isoproterenol decreased 7 days after exposure to MMA-HS. Exposure to MMA-HS slightly reduced blood pressure in response to norepinephrine at 1 day post-exposure, but this change was not statistically significant. In addition, pulmonary exposure to MMA-HS reduced the phosphorylation level of cardiac troponin I in the heart. This was consistent with the reduced heart muscle contractility indicated by decreases in left ventricular pressure, positive and negative dp/dt. These findings suggest that the heart may be more prone to developing dysfunction than the vascular system after exposure to welding fumes.
Laboratory-animals; Laboratory-techniques; Laboratory-testing; Exposure-assessment; Exposure-methods; Exposure-levels; Lung; Pulmonary-system; Immune-reaction; Particulates; Cardiovascular-disease; Cardiovascular-function; Cardiovascular-system; Cardiovascular-system-disease; Heart; Welders; Welding; Arc-welders; Arc-welding; Metal-fumes; Metallic-fumes; Metal-compounds
The Toxicologist. Society of Toxicology 51st Annual Meeting and ToxExpo, March 11-15, 2012, San Francisco, California