Monitoring of heavy metal contamination in human blood-population exposed to different wastewater irrigated agricultural farms and source apportionment in Pakistan

The study was designed to assess the heavy metal contents in human blood of farmers in six agricultural farms irrigated with untreated industrial effluents, urban wastewater, canal and tube well water and source apportionment in peri urban area of Multan city,Pakistan. Human blood samples (n=30) and wastewater, soil, Brassica and Maize plants, Chicken liver, groundwater and raw milk (each n=30) were analyzed for cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni) and lead (Pb) by Inductively Coupled Plasma-optical Emission Spectrometry (ICP- OES). Mean contents of Cd, Cr, Mn and Ni exceeded the WHO safe limits in human blood of population exposed to wastewater farms and all metals were within safe limits at canal and tube well water farms. Contamination level of human blood at industrial wastewater irrigated farm was highest and was lowest at tube well water farm. Total contents of metals in blood were 100 to 350 times higher at wastewater irrigated farms than that at canal water farm. The multivariate statistical analysis indicated that the wastewater, soil and foodstuff grown at respective farms were common sources of human blood contamination. The human population exposed to wastewater irrigated fields may suffer to serious health implications due to blood contamination with heavy metals exceeding safe limits. Use of properly treated wastewater in agricultural farms may safeguard the health of public and ecosystem