Figure 2: Major contaminants encountered, distributed according to (a) continents and (b) climatic zones. All results expressed as percentages of total respondents in each category: BTEX: Benzene, Toluene, Ethylbenzene and Xylene; PAH: Polycyclic Aromatic Hydrocarbons; SAH: Saturated Aliphatic Hydrocarbons; PCB: Polychlorinated Biphenyls; TCE: Trichloroethane; PCE: Perchloroethane; Metals; and AgroX and Pesticides: Agrochemicals and Pesticides. Lines of latitude used for delineations into climatic zones were as follows: Temperate (North): 23.5°N-66.6°N; Tropical: 23.5°N-23.5°S; Temperate (South): 23.5°S-66.6°S. There were no respondents from the Polar Regions. For this study all of China was captured under Temperate (South).