Characterization and origin of organic and inorganic pollution in urban soils in Pisa (Tuscany, Italy)

Abstract

We assessed the quality of 31 urban soils in Pisa by analyzing total petroleum hydrocarbons (TPHs), Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, and the platinum group elements (PGEs). The risk was evaluated by the geological accumulation index (I ) and the enrichment factor (EF). Results were compared with those obtained from a non-urban site and with the quantitative limits fixed by Italian legislation. In nearly all the monitored sites, the legal limit for TPH of 60 mg/kg in residential areas was exceeded, indicating widespread and intense pollution throughout the entire city area. The I indicated no Cd, Cu, Mn, Ni, and Zn pollution and minimal Pb and Cr pollution due to anthropogenic enrichment. Legal Hg and Zn limits of 1 and 150 mg/kg, respectively, were exceeded in about 20% of sites; Cd (2 mg/kg), Cr (150 mg/kg), and Cu (120 mg/kg) in only one site; and the Ni legal limit of 120 mg/kg was never exceeded. Some urban soils showed a higher Hg level than the more restrictive legal limit of 5 mg/kg concerning areas for industrial use. Based on the soluble, exchangeable, and carbonate-bound fractions, Mn and Zn showed the highest mobility, suggesting a more potential risk of soil contamination than the other metals. The TPH and both Cr and Hg amounts were not correlated with any of the other monitored metals. The total contents of Cd, Pb, Zn, and Cu in soils were positively correlated with each other, suggesting a common origin from vehicular traffic. The PGE values (Pt and Pd) were below the detection limits in 75%-90% of the monitored areas, suggesting that their accumulation is at an early stage.

The Complex Issue of Urban Trees—Stress Factor Accumulation and Ecological Service Possibilities

“…The major source of these particles are fertilizers from areas cultivated nearby, household waste, weathering products for building materials, construction waste, low-particle dust emitted by households, and transportation byproducts, such as fuel combustion products or the abrasion of vehicle parts. Soil pollution has been documented along roadsides in cities all over the world, including China [44], Brazil [45], India [46], Russia [47], Iran [48], Turkey [49], Australia [50], Italy [51], Germany and Poland [52], among others. This underlines the large scale of the problem.…”

Contamination and Hazard Risk Assessment of Potentially Toxic Elements in Road Dust Lagos, Southwest, Nigeria

“…Road dust is increasingly recognised as an environmental pollution indicator in urban cities worldwide [1]. The generation of dust has been linked to mining, construction, farming, vehicular traffic, industrial emitters and natural sources and its chemical composition by these anthropogenic activities, specifically chemical plants, fuel combustion, wearing of tyre, brake and road surfaces and household waste [2], [3], [4], [5], [6]. Road dust can be referred to as the accumulation of impervious solid particles with a very short half-life of between 190 to 370 days [7] owing to the ease of resuspension into the atmosphere [8] or washed away as street run off through precipitation to become an important component of suspended and dissolved solids [9].…”