Evaluation of Heavy Metal Pollution Characteristics in Greenhouse Soils of Antalya (Turkey)

Abstract

To evaluate the heavy metal pollution of intensive greenhouse regions of Antalya, the relations among the soil, greenhouse plants and groundwater properties and heavy metal characteristics were determined and several environmental pollution indexes were used to evaluate the size of pollution and risks. Groundwaters of greenhouse area have low conductivity but high nitrate content. Heavy metal contents of groundwaters were below the permissible levels, and the average heavy metal evaluation index (HEI) values for all metals in groundwaters were below the critical value.The concentration of heavy metals with the exception of Ni in soils of greenhouses were generally below the referenced limits. Soil metal speciation showed that the greatest percentage of all metals was present in the residual form, and the mobility of metals declined in the following order: As>Cd>Zn>Pb>Ni. Single factor and composite pollution coefficient values of all metals with the exception of Ni were not exceeded critical limit. Anthropogenic and enrichment factor indexes of greenhouse soils indicate that both two parameter showed similar trends and 1 to 5 fold metal enrichment by anthropogenic inputs compared to uncontaminated soil. On the basis of total concentration, potential ecological risk indexes of soil metals except Ni were found below the threshold value that indicate these metals have a low risk to surrounding environment. But mobility factor of Ni element in greenhouse soil was found considerably low. All heavy metal
concentrations with the exception of Cd in tomato fruits were found below the permissible heavy metal limits. However, target hazard quotient (THQ) indexes of tomato fruits were found below the critical value and thus it can be presumable no health risk for Cd metal in short or medium
terms. Although soil total Ni concentration was excessed the pollutant limits, possibly due to low soil mobility factor of Ni, concentration of Ni in tomato fruit was found very low.In a comprehensive manner, in addition to total concentrations referenced for soil metal pollution assessment, metal bioavailability studies may provide useful information for assessing environmental risks.