Novel contaminants identified in fish kills in the Red River watershed, 2011-2013.

Provisional molecular weights and chemical formulas were assigned to 4 significant previously unidentified contaminants present during active fish kills in the Red River region of Oklahoma. The provisional identifications of these contaminants were determined using high-resolution liquid chromatography-time-of-flight mass spectrometry (LC-TOFMS), LC-Fourier transform ion cyclotron resonance mass spectrometry (LC-FTICRMS), and LC-ion trap mass spectrometry (LC-ITMS). Environmental water samples were extracted using a solid-phase extraction (SPE) method, and sediment samples were extracted using a modified sonication liquid extraction method. During screening of the samples, 2 major unknown chromatographic peaks were detected at m/z 624.3 and m/z 639.3. The peak at m/z 639.3 was firmly identified, through the use of an authentic standard, as a porphyrin, specifically chlorin-e6-trimethyl ester, with m/z 639.31735 (M + H)+ and molecular formula C37 H43 N4 O6 . The other major peak, at m/z 624.3 (M + H)+ , was identified as an amide-containing porphyrin. It was discovered that the amide compound was an artifact created during the SPE process by reaction of ammonium hydroxide at 1 of 3 potential reaction sites on chlorin-e6-trimethyl ester. Other unique nontargeted chemicals were also detected and the importance of their identification is discussed. Environ Toxicol Chem 2018;37:336-344. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Trace level haloacetic acids in drinking water by direct injection ion chromatography and single quadrupole mass spectrometry.

Chlorine has been widely used to kill disease-causing microbes in drinking water. During the disinfection process, organic and inorganic material in source waters can combine with chlorine and certain other chemical disinfectants to form disinfection by-products. The kind of disinfectant used can produce different types and levels of disinfectant byproducts in the drinking water, such as trihalomethanes and haloacetic acids (5HAAs). Currently, USEPA Method 552 utilizes a methyl tert-butyl ether extraction and diazomethane derivatization of HAAs and phenolic disinfectant by-products, and a gas chromatograph equipped with a capillary column to perform the separation of methyl-haloacetates and anisoles. To detect, gas chromatography and electron capture detector are used. This article demonstrates a simple method using direct injection ion chromatography hyphenated with mass spectrometry for the analysis of 5HAAs.