Human exposure to arsenic in groundwater from Lahore district, Pakistan

• As levels were measured in children, adults and old age from Lahore, Pakistan.
• Different sites showed significant differences in levels of total As.
• Blood and nail As concentrations showed a significant (p < 0.05) positive correlation.
• Antioxidants enzymes activity decreased with increase in As concentrations.

In the present study we determined As concentrations in healthy volunteers from three different age groups (children, adults and old age) residing in Lahore, Pakistan to gain insight into arsenic exposure to humans via drinking water. The results revealed that the concentrations of As were significantly (p < 0.05) different among different sites, while non significant trends were observed among different age classes. As concentrations in blood and nails samples showed a significant (p < 0.05) positive correlation. The mean concentrations of As were higher in nails samples (1.43 μg/g) followed by blood samples (1.15 μg/L); urine samples (0.82 μg/l) and hair samples (0.74 μg/g) based on all sites. The antioxidants enzyme activities in blood samples showed a significant (p < 0.01) decrease with the increase in As concentrations. The result suggests that urgent action is needed to prevent further human exposure to As.