Sex differences in cardiopulmonary effects of acute bromine exposure

Accidental occupational bromine (Br>2>) exposures are common, leading to significant morbidity and mortality; however, the specific effects of Br>2> inhalation in female victims are unclear. Our studies demonstrated that acute high-concentration Br>2> inhalation is fatal, and cardiac injury and dysfunction play an important role in Br>2> toxicity in males. In this study, we exposed female Sprague Dawley rats, age-matched to those males from previously studied, to 600 ppm Br>2> for 45 min and assessed their survival, cardiopulmonary injury and cardiac function after exposure. Br>2> exposure caused serious mortality in female rats (59%) 48 h after exposure. Rats had severe clinical distress, reduced heart rates and oxygen saturation after Br>2> inhalation as was previously reported with male animals. There was significant lung injury and edema when measured 24 h after exposure. Cardiac injury biomarkers were also significantly elevated 24 h after Br>2> inhalation. Echocardiography and hemodynamic studies were also performed and revealed that the mean arterial pressure was not significantly elevated in females. Other functional cardiac parameters were also altered. Aside from the lack of elevation of blood pressure, all other changes observed in female animals were also present in male animals as reported in our previous study. These studies are important to understand the toxicity mechanisms to generate therapies and better-equip first responders to deal with these specific scenarios after bromine spill disasters.>