Cleanup levels at an oil distribution and storage station in eastern central Mexico determined from a health risk assessment

The subsoil of an oil storage and distribution station located in eastern central Mexico was characterised in terms of some fuel fractions and metals. The site was found to be contaminated mainly with total petroleum hydrocarbons (TPHs) at a concentration higher than that legislated in Mexico. The presence of BTEX (benzene, toluene, ethylbenzene and xylenes) and 11 of the 16 USEPA polynuclear aromatic hydrocarbons (PAHs) were also identified. The health risk assessment carried out indicated that only dibenzo(a,h)anthracene was found at a concentration that exceeds the previously fixed minimum acceptable risk, and must be reduced. The TPH actual concentration must be reduced up to a value of 2.00 mg/kg. The Adult Lead Methodology (ALM) indicated that the maximum lead concentration present in the soil is lower than the value of 435 mg/kg, which would cause a maximum concentration of 10 μg/dl on the blood of foetus of women exposed to lead-contaminated soils.