has revealed a significant increase in the incidence of liver cancer at a higher level of arsenic exposure (>0.64 mg/L). However, no such associations have been found at lower levels of Arsenic. Moreover, the significant differences obtained are irrespective of gender.
Reports related to the association of high concentration of arsenic with prostate cancer have resulted from studies conducted in Taiwan. However, reports on association of prostate cancer to lowe concentration of arsenic exposure is lacking. Recent studies on the basis of urine collected (to determine the levels of arsenic) from 3932 Native Americans (45 to 74 years of age) have revealed that exposure to low-to-medium levels of arsenic results in a high prostate cancer mortality hazard ratio (3.30; 95% CI, 1.28 to 8.48). This value was found to be higher than that observed for liver cancer (1.56; 95% CI, 1.02 to 2.39).
There has been very few reports that attempts to draw parallel between leukemia and arsenic exposure. One report suggested that the incidence rate of leukemia was about 4 times higher in arsenic (70 ?g/L) and chromium (240 ?g/L) contaminated region than the average value observed in US. Additionally, significant association between keukemia and arsenic exposure have been reported in pregnant mothers in studies conducted on pediatric leukemia patients in California.
Non-Carcinogenic effects of Arsenic
Neurological effects, intellectual and memory function
There has been increased association of neurobehavioral changes and abnormalities during puberty and adult stages with the accumulation of arsenic in the body. The effects may get enhanced with lead exposure. One of the neurological complications associated with arsenic is neuritis, resulting in adverse effects on the sensory functions of the peripheral nerves. Deficiency in long-term memory formation and verbal intelligence quotient has been observed in association with arsenic exposure in Mexican children. The effects are enhanced in proportion with the drug. However, these effects are also controlled by the length of arsenic exposure as well as the intake of several nutritional factors.