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Trace Elements in Abiotic and Biotic Environments
for the blood and 0.5–15 ng/L and 0.18 μg/L for urine have been reported (Vaughan
and Florence 1992). Pt levels of 0.1 to 2.8 μg/L in the blood are in the general population. In serum, of occupationally exposed workers, Pt levels range from 150 to
440 μg/L. The principal Pt deposition sites are the kidneys, liver, spleen, and adrenals. The high amount of 191 Pt found in the kidney shows that once Pt is absorbed,
most of it is accumulated in the kidney and is excreted in the urine. The lower level
in the brain suggests that Pt ions cross the blood–brain barrier, but to a limited extent
(WHO 1991b).
Metallic Pt is considered to be biologically inert and nonallergenic, and because
the emitted Pt is probably in metallic, or oxide, form, the sensitizing potential is
presumably very low. Platinum from the road dust, however, can be solubilized and
enters into water, sediments, soils, and the food chain (Ravindra et al. 2004).
Platinum compounds provide an excellent illustration of the need to differentiate
the chemical species of an element, when evaluating its allergenic potential. Allergic
symptoms including rhinitis, asthma, and urticaria have been reported after World
War II in workers employed in Pt refineries and in secondary users, mainly from the
manufacture or recycling of catalysts plants (WHO 2006a).
Platinum compounds, especially soluble salts, are toxic, and chronic industrial
exposure to these compounds is responsible for the development of a syndrome
known as platinosis, which is characterized by respiratory and cutaneous hypersensitivity. The acute toxicity of Pt depends mainly on the Pt species. Soluble Pt
compounds are much more toxic than insoluble ones. Exposure to Pt salts is mainly
confined to occupational environments, primarily to Pt metal refineries and catalyst
manufacture plants.
Platinum nanoparticles, with different sizes, showed the different bacterio-toxic
or compatible properties with the clinical pathogen (Gopal et al. 2013).
cis-Diaminedichloroplatinum(II), cis-(NH 3 ) 2 PtCl 2 , clinically called cisplatin is
one of the most successful anticancer compounds. After the discovery of its activity,
thousands of Pt complexes have been synthesized and evaluated for their anticancer
activity. Research in the field of Pt-based cancer chemotherapy showed that cisplatin
and its analogous compounds exhibit very similar patterns of antitumor sensitivity
and susceptibility to resistance, which means that most of them produce identical
adducts with DNA (Abu-Surrah et al. 2008).
The concentration of Pt in the sewage of hospitals is originating from excreted
antineoplastic drugs. About 70% of Pt, administered in the form of either cisplatin
or carboplatin, is excreted, and therefore, it ends up in hospital effluents. Pt concentrations, measured in the total effluents of hospitals, ranged widely from <10 ng/L
to approximately 3500 ng/L. Nursing staffs are evidently concerned about the risk
of hazardous exposure of Pt, due to increasing use and contact with antineoplastic
drugs (Ravindra et al. 2004).
The International Agency for Research on Cancer considered the evidence for
carcinogenicity of cisplatin for animals to be sufficient, but that for humans inadequate. Cisplatin is classified in Group 2A, that is, probably carcinogenic to humans
(IARC 1987, 2013).