assessment of human health risk and surface soil contamination by some toxic elements in arak city, iran

Background: population growth, numerous factories, and many vehicles are the primary sourcesof environmental pollution and toxic elements in the industrial city of arak, iran.methods: in june 2016, a total of 30 toxic element samples were taken from surface soilsto examine their contents of lead (pb), zinc (zn), copper (cu), nickel (ni), arsenic (as),chromium (cr), and cadmium (cd). the samples were collected from 0 to 20 cm depth andmeasured using atomic absorption spectroscopy (aas) (pg990 model).results: the results showed that the mean concentrations of all toxic elements except arsenic hada higher value than the background values in the world. the top enrichment factor (tef) of toxicelements of nickel, chromium, lead, and copper was higher than other elements. the potentialecological risk (per) index showed high and very high risk for the elements. for all elements,the hazard index (hi) values were higher for children than for adults. moreover, the results ofcarcinogenic health risk assessment (carcinogenicity risk [cr]) of the toxic elements for cr inchildren with an average value of 0.001 and adults with an average value of 3.81e-04 showed thatthe cr of chromium for children poses a serious threat to the health of children and adults.conclusion: in general, the toxic element pollution for the surface soil of arak is of concern, andsignificant measures should be taken to reduce the pollutants.