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6.2 Sources of Soil Pollutants 181

Fig. 6.21 Structures of
phthalate ester and bisphenol A

Chronic effects of benzene, toluene, and xylene include changes in the liver and
harmful effects on the kidneys, heart, lungs, and nervous system.
Phthalate esters (PAEs) which are widely used in plastics, automotive, clothing,
cosmetics, lubricants, and pesticides industries can enter into the environment easily
and regularly. PAEs (structure in Fig. 6.21 ) are persistent in the environment and

often have cumulative effect and amplification of biological effects, which can enter
the food chain and endanger human health. In general, PAEs are considered to be
endocrine disrupting chemicals (EDCs), whose effects may not appear until long
after exposure (Daiem et al. 2012 ).

6.2.11.1 Hazards of Organic Pollutants

Human health risks of organic pollutants include allergies, damage to the nervous
system, disruption of the immune system, reproductive disorders, and cancer (van
der Perk 2006 ). Some volatile organic compounds such as tetrachloroethylene,
trichloroethylene, dichloroethylene, and vinyl chloride or chloroethylene, which
may contaminate the soil, are potential carcinogens. Chlorinated aromatic compounds
such as hexachlorobenzene and pentachlorophenol, polychlorinated biphenyls, and
PAHs are also potential carcinogens. They are lipophilic and bioaccumulate in fatty
human tissues. Occupational and accidental high-level exposure to some POPs is of
concern for both acute and chronic worker exposure. The greatest risk is found
where the use of POPs in tropical agriculture has resulted in a large number of
deaths and injuries. Worker exposure to POPs during waste management is a signifi cant
source of occupational risk in many countries. Short-term exposure to high concen-
trations of certain POPs has been shown to result in illness and death. A study in the
Philippines showed that in 1990 endosulfan became the number one cause of pesti-
cide-related acute poisoning among subsistence rice farmers and mango sprayers.
The earliest reports of exposure to persistent organic pollutants related to human
health impact include an episode of HCB poisoning of food in southeast Turkey,
resulting in the death of 90 % of those affected and in other exposure related
incidences of hepatic cirrhosis, porphyria, and urinary, arthritic, and neurological
disorders (Peters 1976 ). In another acute incident in Italy in 1976, release of 2,3,7,8-
TCDD to the environment resulted in a purported increase of chloracne and an
increased leukemia- and thyroid cancer-related mortality (Pestaori et al. 1993 ).
More recently, the USEPA have been reviewing the dioxin-related health effects,
especially for the noncarcinogenic endpoints such as immunotoxicity, reproductive
diseases, and neurotoxicity.