Concentrations of cadmium, lead, chromium and copper in the blood samples collected from different groups of the population, living in and around the city of Lahore were determined in order to assess the exposure levels of these metals in the industrial workers and general population exposed to environmental pollutants. The groups were comprised of normal males and females; exposed industrial workers, laboratory workers and cancer patients.
The male industrial worker and exposed female groups were found to contain higher lead-blood levels than I the normal groups. Cancer patient groups were found to contain the highest lead-blood concentrations than all the groups studied. The results showed higher blood-lead levels for all male groups compared to the female groups.
Cadmium-blood concentrations were found to be higher for male industrial worker s and exposed female groups compared to the normal groups. Significantly low cadmium-blood levels were observed for cancer patients of both sexes. There appears to be a possible 1ink between lead add cadmium blood levels and cancer.
Chromium and copper-blood levels were generally higher f or females of all groups compared to the male groups. No significant variations were observed for copper-blood levels for exposed and cancer patients groups of both sexes. Almost similar chromium-blood levels were observed for industrial worker and cancer patient groups.
The levels of heavy metals in blood for normal groups were generally higher than those for the similar groups in different parts of the world
In order to investigate the major possible sources metallic pollutants, such as cadmium, lead, chromium nickel and copper, the contents of these metals were determined in water and commonly used food commodities.
Tap water samples were found to contain heavy medals below the permissible limits except lead, whereas city sewage water contained elevated levels of heavy metals.
Concentrations of cadmium, lead, chromium, nickel and copper were determined in urban (polluted) and rural (polluted) and rural vegetables, rice, wheat, pulses, spices, refined and raw s gar, meat (beef, mutton and chicken), vegetable oil and hyrogenated vegetable oil (vegetable ghee). Elevated levels of these toxic metals were found in urban vegetables, spices and beef Nickel was found to be 4.4 times higher in vegetable ghee than the maximum permissible limits.
Dietary data showed that the prime source of heavy metals intake by city population were vegetables and cereals. These sources contribute 79-93% of the total food intakes. Forty percent of the total nickel intake in the body is contributed by vegetable ghee source only.
High intakes of cadmium, lead chromium etc. from various source by the city population have been reflected in the elevated levels of these metals in the blood of the general population and exposed industrial worker groups. Experimental/ statistical data reveal that industrial worker who are exposed to these toxic metals while working in iron/steel re-rolling mills/foundries, electroplating, printing, paint/ pigment, leather tanning, chemicals, rubber, tyre and plastic manufacturing etc. industries are at much higher risk of various types of disease including caner compared to the normal persons.