Determination of Trace Phthalic Acid Monoesters in Sediments and Soils by GC-MS

Abstract

A simple procedure for determining trace phthalic acid monoesters (PAMs) in sediments/soils was developed. The method used ultrasonic extraction, silylation derivatization, and GC-MS. After ultrasonic extraction, the supernatants were reextracted with dichloromethane, silylated, and did not require further clean-up before GC-MS analysis. Effects of parameters, such as extraction solvents, pH of water as extraction solvent and sediment/soil properties, on the recovery of PAMs were studied. Five sediments from Tianjin city and one red soil from Jiangxi province were used. The results showed that organic carbon (OC) content played an important role in the recovery of PAMs. The optimal extraction solvent for sediments/soils with >1% of OC content and high CEC was 0.01 M HCl aqueous solution and pure water was better for sediments/soils with <1% of OC content. In 5 g sediment/soil sample (dry weight), the method detection limit (MDL) was below 0.04 ng/g for mono-n-butyl phthalate (MBP) and 0.02 ng/g for mono-(2-ethylhexyl)-phthalate (MEHP). Average recoveries of MBP and MEHP were 81.6%−105.2% and 76.0%−95.6%, respectively, with relative standard deviations ≤ 6.6%. MBP and MEHP in the sediment and soil samples studied were detected at levels of 9. 2-57.1 and 13.0-166.7 ng/g, respectively.

Uptake and Metabolism of Phthalate Esters by Edible Plants

“…To determine the concentrations of MPEs, the dried plant tissue samples from both PAE- and MPE-treated groups, the soil samples, and cell material samples were spiked with deuterated MnBP and MEHP as recovery surrogates and then extracted in a sonication water bath with 15 mL of deionized water twice, 15 min for each extraction . The extracts were centrifuged at 3000 rpm for 30 min.…”

“…19 The extracts were centrifuged at 3000 rpm for 30 min. The supernatants were combined and acidified to pH 2 with glacial acetic acid and then liquid−liquid extracted using 3 mL of methylene chloride (three consecutive times, each for 10 min).…”

“…To determine the concentrations of MPEs, the dried plant tissue samples from both PAE-and MPE-treated groups, the soil samples, and cell material samples were spiked with deuterated MnBP and MEHP as recovery surrogates and then extracted in a sonication water bath with 15 mL of deionized water twice, 15 min for each extraction. 19 The extracts were centrifuged at 3000 rpm for 30 min. The supernatants were combined and acidified to pH 2 with glacial acetic acid and then liquid−liquid extracted using 3 mL of methylene chloride (three consecutive times, each for 10 min).…”

“…Likewise, mono­(2-ethylhexyl) phthalate (MEHP), a primary metabolite of DEHP, may account for toxicity effects of orally ingested DEHP . However, even though MPEs likely coexist with PAEs in soil, ,, at present there is no information on plant uptake of MPEs. Studies on pesticides have highlighted the capacity of plant metabolism after uptake .…”

Thyroid Endocrine Disruption in Zebrafish Larvae after Exposure to Mono-(2-Ethylhexyl) Phthalate (MEHP)

“…For instance, Suzuki et al, observed MEHP in the Tama River in Tokyo at concentrations of 0.01–1.3 μg/L (2001). A recent study demonstrated that MEHP was detected in all sediment and soil samples ranged from 13.0 to 166.7 ng/g [14]. Moreover, MEHP has been widely detected in human biological samples such as milk, urine, saliva, and serum [15]–[19].…”