Cadmium Pollution in the Tourism Environment: A Literature Review

Cadmium is a highly-toxic metal, and, its environmental occurrence and human exposure consequently deserve close attention. The insight into the relationships between cadmium and tourism relations has deepened during the past three decades and the research into this relationship is reviewed. For this purpose, 83 relevant publications (mainly articles in international journals) were analyzed. It was found that investigation of Cd in the tourism environment took place in all continents (except Antarctica) and has intensified since the mid-2000s; Chinese researchers are the most active contributors. The Cd occurrence in air, living organisms, sediments, soil, suspended particular matter, water, and of the human environment has been studied. It has become clear that tourism contributes to Cd pollution (particularly, by hotel wastewater and increased traffic), and, vice versa, Cd pollution of beaches, coastal waters, food, urban parks, etc. creates risks for tourists and increases human exposure to this toxic metal. Both mechanisms have received equal attention. Examples concern many places worldwide, with the Mediterranean and Central and Eastern Europe as apparently critical regions. Our significantly incomplete knowledge of the relationships between cadmium and tourism must be ascribed to the common oversimplification of these relationships and to the scarcity or even absence of information supplied by the most important tourist destinations. The present review demonstrates that more studies of heavy metals and, particularly, Cd in the tourism environment are needed.

Emission and control characteristics for incineration of Sedum plumbizincicola biomass in a laboratory-scale entrained flow tube furnace

Experiments were conducted to investigate and control pollutant emission from incineration of Sedum plumbizincicola plants on a laboratory scale using an entrained flow tube furnace. Without control technologies, the flue gas contained 0.101 mg Nm(-3) of Cd, 46.4 mg Nm(-3) of Zn, 553 mg Nm(-3) of NOx, 131 pg Nm(-3) of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/Fs) and 35.4 mg Nm(-3) of polycyclic aromatic hydrocarbons (PAHs). In pollutants control experiments. Al2O3, CaO, and kaolin were compared as adsorbents and activated carbon was used as an end-of-pipe method for the capture of pollutants. Kaolin, the most effective of the three adsorbents, removed 91.2% of the Cd in flue gas. While 97.6% of the Cd and 99.6% of the PAHs were removed by activated carbon. Incineration may therefore be regarded as a viable option for the safe disposal of the biomass of the zinc and cadmium hyperaccumulator species S. plumbizincicola.