Characterization of Halogenated Organic Compounds in Pelagic Sharks and Sea Turtles Using a Nontargeted Approach.

Halogenated organic compounds (HOCs) in marine species collected from the Atlantic Ocean [3 shortfin mako (Isurus oxyrinchus) and 1 porbeagle (Lamna nasus)], and 12 sea turtles collected from the Pacific Ocean [3 loggerhead (Caretta caretta), 3 green (Chelonia mydas), 3 olive ridley (Lepidochelys olivacea), and 3 hawksbill (Eretmochelys imbricata)] were analyzed with a nontargeted analytical method using two-dimensional gas chromatography coupled to high-resolution time-of-flight mass spectrometry. Sharks and sea turtles had distinct HOC profiles. Halogenated methoxyphenols (halo-MeOPs) were the most abundant compound class identified in sea turtle livers, while polychlorinated biphenyls (PCBs) were the most abundant in shark livers. In addition to legacy contaminants and halo-MeOPs, a total of 110 nontargeted/novel HOCs (NHOCs) were observed in the shark livers. Shortfin mako collected from the northern Gulf of Mexico contained the largest number (89) and most diverse structural classes of NHOCs. Among all NHOCs, a group of compounds with the elemental composition C14H12-nCln (n = 5-8) exhibited the highest concentrations, followed by chlorocarbazoles and tris(chlorophenyl) methanes (TCPMs). Using nontargeted workflows, a variety of known and unknown HOCs were observed, which demonstrate the need to develop more complete chemical profiles in the marine environment.

Nontargeted Screening of Halogenated Organic Compounds in Fish Fillet Tissues from the Great Lakes.

Fish have been used for decades as bioindicators for assessing toxic contaminants in the Great Lakes ecosystem. Routine environmental monitoring programs target predetermined compounds that do not reflect the complete exposure of chemicals to biota and do not provide the complete halogenated fingerprint of the biota. In the current work, a nontargeted screening method was developed using a two-dimensional gas chromatograph coupled to a high-resolution time-of-flight mass spectrometer and was applied to 149 edible fish fillets from different species in the Great Lakes to characterize a more robust set of halogenated organic compounds across species and among lakes. Lake Ontario had the largest number of novel halogenated organic compounds (NHOCs). Seven NHOCs were observed in species from all lakes, indicating that this regional signature was not species-dependent. Hierarchical cluster analysis showed identical NHOC profiles between bottom dwelling and pelagic species. The NHOCs were grouped into seven clusters with similar structures and potentially similar environmental behaviors. Seven of the 29 NHOCs likely containing methoxy or ethoxy groups on a benzene or benzene-methanol backbone were clustered into one group with similar retention times. Five NHOCs were clustered with legacy contaminants that likely have similar structures or are their degradation products.

[Relationship between thyrotropin and urine iodine in Han and Uygur nationalities pregnancy women in People's Hospital of Xinjiang Uygur Autonomous Region].

Objective: To investigate the relationship between thyrotropin (TSH) and urine iodine in pregnant women of Han and Uygur ethnic groups in People's Hospital of Xinjiang Uygur Autonomous Region. Methods: A total of 1 568 pregnant who completed screening of TSH and urine iodine in People's Hospital of Xinjiang Uygur Autonomous Region hospital from August 2014 to December 2017 were included in the study, 956 cases were Han and the other 612 were Uygur. Basic clinical data, serum TSH, thyroid peroxidase autoantibody (TPOAb) , and urine iodine levels were retrospectively analyzed. Results: (1) General results: The median urine iodine level was 162.6 µg/L (53.4-539.3 µg/L) , and the distribution of urine iodine classification was iodine deficiency 42.9% (672/1 568) , iodine appropriate 36.7% (576/1 568) , iodine slightly high 17.1% (268/1 568) and iodine excess 3.3% (52/1 568) respectively. (2) The median urine iodine levels of Han and Uygur pregnant women were 169.1 µg/L (54.6-583.4 µg/L) and 156.3 µg/L (53.1-539.3 µg/L) respectively, and the difference was statistically significant (P<0.05) .The distribution of urine iodine status in pregnancy between Han and Uygur was significantly different, which were 40.9% (391/956) vs. 45.9% (281/612) in iodine deficiency, 35.4% (338/956) vs. 38.9% (238/612) in iodine appropriate, 20.2% (193/956) vs. 12.3% (75/612) in iodine slightly high and 3.6% (34/956) vs. 2.9% (18/612) in iodine excess. (3) High serum TSH level proportion was significantly higher in Uygur ethnic group, early pregnancy, thyroid peroxidase antibody positive and anti-thyroglobulin antibody positive group when compared with Han, late pregnancy, thyroid peroxidase antibody negative and anti-thyroglobulin antibody negative groups (all P<0.05) . There were no significant differences in different age groups and iodine nutrition groups (P>0.05) . (4) There was no correlation between urinary iodine and TSH levels in all pregnant women (P>0.05) , neither in Han or Uygur group. When further stratified by gestational age, age, and antibody level, there was a positive correlation between urine iodine and serum TSH level in Han pregnant women >30 years old (P<0.05) , and there was a negative correlation in the third trimester in Uygur (P<0.05) . When serum antibody level, gestational week and age were controlled. There was no correlation between urine iodine and serum TSH level in neither group. Conclusions: (1) In Han and Uygur pregnant women, the median urine iodine level and the distribution of urine iodine classification between two ethnic groups are significantly different. (2) The correlation between urine iodine and serum TSH is not identified in Han or Uygur pregnant women.

Comprehensive Analysis of the Great Lakes Top Predator Fish for Novel Halogenated Organic Contaminants by GC×GC-HR-ToF Mass Spectrometry.

The U.S. Environmental Protection Agency's Great Lakes Fish Monitoring and Surveillance Program (GLFMSP) has traced the fate and transport of anthropogenic chemicals in the Great Lakes region for decades. Isolating and identifying halogenated species in fish is a major challenge due to the complexity of the biological matrix. A nontargeted screening methodology was developed and applied to lake trout using a 2-dimensional gas chromatograph coupled to a high resolution time-of-flight mass spectrometer (GC×GC-HR-ToF MS). Halogenated chemicals were identified using a combination of authentic standards and library spectral matching, with molecular formula estimations provided by exact mass spectral interpretation. In addition to the halogenated chemicals currently being targeted by the GLFMSP, more than 60 nontargeted halogenated species were identified. Most appear to be metabolites or breakdown products of larger halogenated organics. The most abundant compound class was halomethoxyphenols accounting for more than 60% of the total concentration of halogenated compounds in top predator fish from all five Great Lakes illustrating the need and utility of nontargeted halogenated screening of aquatic systems using this platform.