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A rapid method for the determination of five organophosphorus flame retardants (OPFRs) in textile wastewater was established by dispersive liquid-liquid microextraction (DLLME) based on solidification of floating organic drop (SFO) coupled with ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The analytes were extracted from the water samples by SFO-DLLME, which was performed using a mixture of an extraction solvent that was less dense than water, 1-undecanol, and a dispersive solvent, methanol. The influences of the SFO-DLLME parameters on the extraction efficiencies were studied. 1-Undecanol (extraction solvent, 400 μL) and methanol (dispersive solvent, 300 μL) were added to textile wastewater (containing 2 g NaCl) with pH between 6 and 9, and the solution was shaken for 2 min. Under optimum conditions, the linear ranges of the proposed method were from 2 μg/L to 100 μg/L with correlation coefficients ( R 2 ) above 0.99 for all the analytes. The limits of detection ( S/N =3) ranged from 2 μg/L to 5 μg/L. The precision of the method was evaluated in terms of repeatability; the relative standard deviations varied from 2.7% to 11.2% ( n =6). The relative recoveries ranged from 71.6% to 117.6% for all analytes. Only 3 of the 11 selected samples were tested positive for OPFRs, and the total concentrations of OPFRs in them were in the range of 2.6-3.4 μg/L. Hence, this method is accurate, environmentally friendly, fast, and convenient for the routine analysis of OPFRs in textile wastewater.

An efficient method based on liquid-liquid extraction and dispersive liquid-liquid microextraction coupled with gas chromatography-mass spectrometry was developed for the determination of trace azo dyes in textile wastewater. The azo dyes were reduced to aromatic amines by sodium dithionite under alkaline conditions. The main pretreatment conditions that affected the extraction efficiency were optimized. Under the optimized experimental conditions, the linear ranges of this method were as follows:0.05-10 μg/L for 13 aromatic amines; 0.05-5 μg/L for 7 aromatic amines; and 20-100 μg/L for 2,4-diaminoanisole. The correlation coefficients were in the range of 0.996-0.999. The limits of detection reached 0.05 μg/L for all the 20 aromatic amines, and the detection limit of 2,4-diaminoanisole was 20 μg/L. Actual wastewater-spiked experiments involving printing, dyeing, and weaving showed that the average recoveries of the amines were in the range of 75.6%-115.1%. The developed method has high enrichment multiples and low detection limits, and it is suitable for the detection of trace levels of banned azo dyes in textile wastewater.

A rapid screening method based on high performance liquid chromatography-linear ion trap/orbitrap high-resolution mass spectrometry (HPLC-LTQ/Orbitrap MS) for 22 disperse dyes in ecological textiles has been established. The target compounds were extracted by pyridine/water (1:1, v/v) by shaking extraction in 90 degrees C water bath. The extracts were then separated by a CAPCELL PAK C18 column (100 mm x 2.0 mm, 5 μm) using gradient elution with acetonitrile-5 mmol/L ammonium acetate containing 0.01% (v/v) formic acid as mobile phases, and finally analyzed by HPLC-LTQ/Orbitrap in positive and negative ESI modes. The retention time and accurate mass of parent ion were used for fast screening of 22 disperse dyes, while the confirmatory analysis was obtained by fragments generated by collision-induced dissociation (CID) MS/MS. Target analysis exhibited high mass accuracy (< 5 x 10(-6)). Each target showed a good linearity in its own concentration range and the correlation coefficient was higher than 0.99. The LOQs were 0.125-2.5 mg/kg. Except for Disperse Yellow 49, the average recoveries of most disperse dyes at three spiked levels were 65%-120%, and the relative standard deviations (n = 6) were less than 15%. The method was applied for screening 40 different kinds of textiles, and Disperse Orange 37/76 was detected in one of them. With high selectivity and strong anti-jamming ability, this method is simple, rapid, accurate, and it can be used for the inspection of disperse dyes in textiles.

A method of ultra-performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (UPLC-LTQ/Orbitrap MS) was used to determine 24 free carcinogenic aromatic amines in textiles. The main factors influencing the method, including the extraction solvent, the extraction temperature and the extraction time, were optimized. Under the optimized experimental conditions, the analytes were extracted by dichloromethane for 10 min and loaded into a ZORBAX SB-C18 column (150 mm x 2.1 mm, 5 µm) with a gradient elution of methanol and 0.1% aqueous formic acid solution, and finally detected by LTQ/Orbitrap MS. The screening and quantitative analysis were carried out by the accurate mass of quasi-molecular ion and the peak in extracted chromatogram with accurate mass respectively. The correlation coefficients (R2) were higher than 0.99. The recoveries were 87.8%-105.6% with the RSDs were 1.6%-3.4%. The limits of detection were 0.5-1 µg/kg, and the limits of quantification were 1.5-3 µg/kg. The proposed method was applied to 14 textile samples containing spandex. 4,4'-Diaminodiphenylmethane was determined in five samples and the contents were 0.21-25.6 mg/kg. The results indicate that the developed method is a simple, efficient, precise and reliable technique for the determination of free carcinogenic aromatic amines in textiles.

A method of ultra-performance liquid chromatography-linear ion trap/orbitrap high resolution mass spectrometry (UPLC-LTQ/Orbitrap MS) was used to screen and confirm 24 banned aromatic amines and their 14 isomers at the same time. The main factors influencing the separation including the column, and the nature of make-up solvent were optimized. Under the optimized experimental conditions, the analytes were reduced to banned aromatic amine with sodium dithionite, extracted by methyl tert-butyl ether and loaded onto a ZORBAX SB-C18 column (150 mm x 2.1 mm, 5 μm) with a gradient elution of methanol and 0.1% formic acid aqueous solution, and finally detected by LTQ/Orbitrap MS. The screening and quantitative analysis were carried out by the accurate mass of quasi-molecular ion and the peak in extracted chromatogram with accurate mass. The correlation coefficients were higher than 0.99 and the limits of detection were in the range of 0.5-5 μg/kg. The method could screen and confirm the 24 banned aromatic amines and their 14 isomers at the same time. The results were 1.56 mg/kg of 4-chloroaniline, 0.34 mg/kg of o-toluidine, and 0.81 mg/kg of 2,6-toluylenediamine with the relative standard deviations ranging from 0.27% to 1.32% in actual samples. The results indicate that the developed method is simple, efficient and precise, and can be a reliable technique for the separation of the 24 banned aromatic amines and their 14 isomers in textile samples.

A study for the simultaneous determination of 21 primary aromatic amines derived from the reduction of the azo colorants in plastic components of electrical and electronic products was conducted. Organic solvents were used to dissolve or swell the plastics to release the azo dyes existing in the plastic components. The azo colorants were reduced to aromatic amines under strong reducing condition of dithionite. Aromatic amines were extracted with methyl tert-butyl ether. Methanol-water (1: 1, v/v) was used to concentrate the extract to constant-volume for HPLC-MS analysis. The analytes were separated on a ZORBAX Eclipse XDB C18 column using the gradient elution with acetonitrile and 0.1% (v/v) formic acid aqueous solution at a flow rate of 0.6 mL/min. The analyte confirmation was performed using retention time and characteristic ions in selected ion monitoring (SIM) mode. The correlation coefficients (r) of all the standard curves were more than 0.998, and the limits of quantification of the analytes were 0.5 mg/kg. The recoveries were 60.1% - 129.5% for the 21 aromatic amines with the RSDs not more than 14.0% except for a few compounds. The results showed that the banned azo colorants in the plastic products can be analyzed qualitatively and quantitatively through reductive conversion into aromatic amines. In addition, this method has high accuracy and good precision.

A method of high performance liquid chromatography-linear ion trap/Orbitrap high resolution mass spectrometry (HPLC-LTQ/Orbitrap MS) was used to screen and confirm carcinogenic dyes in textiles. The analytes were extracted from textile samples with pyridine/water (1/1, v/v) in a water bath under controlled conditions (95 degrees C, 150 r/min), and then filtered with a 0.22 microm polytetrafluoroetylene (PTFE) membrane. The eluates were separated on a CAPCELL PAK C18 column (100 mm x 2.0 mm, 5 microm) using gradient elution with acetonitrile/ 5 mmol/L ammonium acetate aqueous solution containing 0.01% formic acid (in positive mode) and acetonitrile/5 mmol/L ammonium acetate aqueous solution (in negative mode), and finally detected by HPLC-LTQ/Orbitrap MS in ESI modes. Full scan experiments were performed over the range of m/z 200-800. The screening and quantitative analysis were carried out by the accurate mass of quasi-molecular ion and the peak area in extracted chromatogram with accurate mass, respectively. The confirmatory analysis for target compounds was performed with the retention time and qualitative fragments obtained by data-dependent scan mode. Under the optimal conditions, nine carcinogenic dyes were routinely detected with mass accuracy below 5 x 10(-6) (5 ppm), and good linearities were provided in their respective linear ranges with correlation coefficients higher than 0.99. The limits of detection were in the range of 0.125-25 mg/kg. The average recoveries at three spiked levels were in the range of 62.13%116.28% with the relative standard deviations (RSDs) lower than 15%. The proposed method was applied to screen and confirm the nine carcinogenic dyes in textile samples. It is convenient and reliable.

A method has been developed for the determination of hexabromocyclododecane (HBCD) in fire proof coatings by gas chromatography-mass spectrometry (GC-MS). The sample was extracted with dichloromethane and purified through an organic membrane before analysis with GC-MS. The characteristic fragments (m/z 157, 239, 319, 401) and the quantitative ion (m/z 239) were selected. With the optimized conditions, the good linear relationship was obtained between the peak area and the mass concentration of HBCD in the range of 5 to 100 mg/L with the correlation coefficient more than 0. 999. The spiked recoveries in the coatings of acrylic and epoxy resins were 92.9% - 116.3% with the RSDs not more than 8%. The LOD (S/N > or = 3) of HBCD was 30 microg/g, and the LOQ (S/N > or = 10) was 100 microg/g, which were much lower than the international maximum residue limit. The method is simple, quick, accurate and precise, which can meet the requirements of the European Commission Regulation (EC) No. 1907/2006 and Norway PoHS instruction (Prohibition on Certain Hazardous Substances in Consumer Products) for the determination of HBCD. It is suitable for the analysis of HBCD in fire proof coatings.

A method was established for the simultaneous determination of some phthalic acid esters, namely, dimethyl phthalate (DMP), diethyl phthalate (DEP), dipropyl phthalate (DPrP), dibutyl phthalate (DBP), diamyl phthalate (DAP), dihexyl phthalate (DHP), benzyln-butyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP), dicyclohexyl phthalate (DCHP), di-n-octyl phthalate (DNOP), diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP) in textiles by solid phase extraction (SPE) coupled with gas chromatography (GC). The phthalic acid esters in textiles were extracted by Soxhlet extraction with hexane, the extracts were then cleaned up and enriched by a strong anion exchange (SAX) SPE cartridge. The parameters affecting the purification efficiency of SPE cartridge, such as solvent conditioning, rinsing, and elution, were studied. Conditioning with 5 mL hexane and rinsing with 3 mL isooctane were proved to be the optimal conditions. Of the several solvent ratios (ethylacetate in hexane) used for selective elution of phthalic acid esters from the SAX SPE cartridge, the 15% (v/v) content for ethylacetate in hexane gave the best result. Under the optimized conditions, the recoveries of phthalic acid esters for spiked standards (n=7) were 86.3%-102.7%, and the relative standard deviations (RSDs) were less than 5%. In this method the detection limits for DMP, DEP, DPrP, DBP, DAP, BBP, DCHP, DEHP, DNOP were all below 1 mg/kg, and the detection limits for DINP and DIDP were 1.74 mg/kg and 1.55 mg/kg respectively. This SPE-GC method is sensitive, accurate and suitable for the analysis of phthalate environmental hormones in textiles.