Wu et al. [50] studied 764 steel mill workers from 6 work sites and showed that harsh working conditions (noise, dust and heat) were associated with an incidence of anti-HSP70 antibodies in 40.6% of hypertensive patients and only 18.6% of normotensive individuals; furthermore, statistical correlations between anti-HSP70 levels and hypertension were more significant in severely (>160/95 mmHg) hypertensive patients. This evidence concerns the gene HSPA1A and hypertensive disorder.