IL6 and COVID-19: Among the severe COVID-19 patients, those in the higher urinary cadmium quartiles had a significantly higher neutrophil/lymphocyte ratio, higher levels of inflammatory markers including ferritin, LDH, IL-6 and CRP, significantly higher risk of organ failure (i.e., higher APACHE II and SOFA scores), and significantly higher risk of hypoxemia (i.e., lower PaO2/FiO2) requiring a significantly higher rate of invasive mechanical ventilation.