Occurrence, Detection Technologies, and Regulations of Phthalic Acid Esters at Atmospheric and Aquatic Environments

Phthalic acid esters or phthalates are widely used as plasticizers in various industrial plastic products. Among various phthalates, Dibutyl phthalate(DBP) and Di-(2-ehtylhexyl) phthalate(DEHP) are the most frequently used phthalates. As the risks of several phthalates have been studied, the use of phthalates is being restricted in many countries. Several studies have revealed that phthalates ubiquitously exist in air and water environments. It is interesting to note that indoor phthalate concentrations were higher than those of outdoor in air environment. In water environment, while a significant amount of phthalates is removed from wastewater treatment plants, there is little difference among phthalate concentrations of tap water, bottled water, lake water and surface water. That means phthalates are not effectively removed from the drinking water treatment plants. There are regulations pertaining to phthalates in Korea, the USA, and the EU. Most regulations are mainly about the allowable amounts when plastic products are manufactured. In Korea, water regulation about phthalates stipulates the wastewater discharge concentration, while the USA water regulation about phthalates set the maximum allowable concentration in drinking water. However, in air, both Korea and the USA only designate phthalates as pollutants, and there is no regulation about the concentration of phthalates. Most studies used Gas Chromatograph-Mass Spectrometer (GC-MS) for detecting phthalates. GC-MS can detect low concentrations of phthalates with precision and reliability, but it is time-consuming and requires expertise. Due to the nature of large footprint, it cannot be used to measure phthalates concentrations directly in situ. Biosensor is a portable technology that allows a rapid detection of target compounds in situ. While sensors that detect phthalates in water are well developed, sensors that detect phthalates in the atmosphere have been less thoroughly investigated in the studies. To effectively manage phthalates in indoor environments, more studies regarding atmospheric phthalate sensor technology may be needed.