Quantification and Risk Assessment of PAHs in Street Dust from Functional Areas of Khamis-Mushait, Saudi Arabia

The average value of polycyclic aromatic hydrocarbons (PAHs) in Khamis-Mushait street dust was 2809.46 ng/g, ranging from 1250.41-4249.29 ng/g. Incinerator and industrial locations had the highest concentration of fossil PAHs (∑FPAHs), accounting for 69.62% of PAHs. The highest concentrations of carcinogenic PAHs (∑CARC) and combustion PAHs (∑COMB) were found in the King Fahd Garden and Al-Hayat National Hospital regions, accounting for 41.70 % and 27.46 % of PAHs, respectively. Naphthalene (NAP), Acenaphthylene (ACY) and Acenaphthene (ACE) were > effective range low (ERL). However, ACE was > effective range medium (ERM), and ACY, ACE, and DBA (dibenzo anthracene) were > Probable Effect Level (PEL). Furthermore, the effects of NAP, fluoranthene (FLT), pyrene (PYR), and benzo (a)pyren (BaP) were greater than the threshold effect level (TEL). The order of Hazardous indices (HI) for both children and adults were ACE > ACY > NAP > PYR > fluorene (FLR) > FLT > benzo (ghi) perylene (BghiP) > phenanthrene (PHN) > ANT. However, total HI for non-cancer risks for PAHs were 2.69×10-2 -9.91×10-5 and 2.50x10-2 - 9.22×10-4 to adults and children, respectively. These values considered safe level and insignificant to adults and children. In addition, ACE may pose risk based on acute and intermediate oral exposure. The cluster analysis of dust samples declared the following order from different sources: traffic > industrial > commercial.