The diversity of naturally produced organohalogens

More than 3800 organohalogen compounds, mainly containing chlorine or bromine but a few with iodine and fluorine, are produced by living organisms or are formed during natural abiogenic processes, such as volcanoes, forest fires, and other geothermal processes. The oceans are the single largest source of biogenic organohalogens, which are biosynthesized by myriad seaweeds, sponges, corals, tunicates, bacteria, and other marine life. Terrestrial plants, fungi, lichen, bacteria, insects, some higher animals, and even humans also account for a diverse collection of organohalogens.     

Structure elucidation of four possible biogenic organohalogens using isotope exchange mass spectrometry

The molecular structures of four unknown bioaccumulating halogenated compounds, C10H6N2Br3Cl3, C10H6N2Br4Cl2, C10H6N2Br5Cl, and C10H6N2Br6 were characterized using isotope exchange positive chemical ionization (IE-PCI) mass spectrometry (MS) and identified by comparison to synthesized standards. NH3 and ND3 were used as reagent gases for the IE-PCI-MS experiment. The shift in mass of the quasimolecular ion between the NH3 and ND3 PCI obtained spectra indicated the number of exchangeable hydrogens attached to the two nitrogen atoms in C10H6N2Br4Cl2, and thus the type of amines present (primary, secondary, or tertiary). 19 compounds (13 amines of varying degree of substitution; six containing no nitrogen) were used as reference compounds and controls in the experiment to validate the IE-PCI technique. The results of the IE-PCI-MS indicated the presence of two tertiary amine functional groups. The molecular structures of the four hexahalogenated compounds were then proposed to be 1,1'-dimethyl-3,3',4,-tribromo-4',5,5'-trichloro-2,2'-bipyrrole, 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-dichloro-2,2'-bipyrrole, 1,1'-dimethyl-3,3',4,4',5-pentabromo-5'-chloro-2,2'-bipyrrole, and 1,1'-dimethyl-3,3',4,4',5,5'-hexabromo-2,2'-bipyrrole and subsequently synthesized. Comparison of retention times and electron capture negative ionization (ECNI) full scans on various gas chromatography (GC) columns between the synthesized bipyrroles and the corresponding unknown compounds in biota indicated that three of the unknown compounds--possible marine natural products--were the proposed halogenated dimethyl bipyrroles. The placement of the halogen atoms on the fourth compound, C10H6N2Br3Cl3 could not be unequivocally determined since the synthesized standard could not be fully characterized.     

Supporting breastfeeding in emergencies: protecting women's reproductive rights and maternal and infant health

Women have the right to support that enables them to breastfeed. Supporting breastfeeding in emergencies is important because artificial feeding places mothers and children at risk. In emergencies, artificial feeding is dangerous to the infant, difficult and requires substantial resources. In contrast, breastfeeding guards infant health. It is also protective against postpartum haemorrhage, maternal depletion, maternal anaemia and closely spaced births and should therefore concern not only nutritionists, but also those involved in reproductive health. However, it is common for women's ability to breastfeed to be undermined in emergencies by the indiscriminate distribution of breast-milk substitutes and the absence of breastfeeding support. Controlling the distribution of breast-milk substitutes, providing supportive environments, and appropriate medical and practical assistance to breastfeeding women safeguards the health and well-being of mothers and babies. Greater collaboration between the nutrition and reproductive health sectors is required to promote best practice in protecting breastfeeding women and their children in emergencies.     

Modeling Dinophysis in Western Andalucía using an autoregressive hidden Markov model

Environmental and Ecological Statistics - Dinophysis spp. can produce diarrhetic shellfish toxins (DST) including okadaic acid and dinophysistoxins, and some strains can also produce non-diarrheic...     

Media messages and the needs of infants and young children after Cyclone Nargis and the WenChuan Earthquake

Infants and young children are vulnerable in emergencies. The media plays an important role in aid delivery and has a positive impact when reports are accurate. However, the media has been implicated in encouraging harmful aid in the form of donations of infant formula and other milk products. Internet‐based media reports were collected after Cyclone Nargis in Myanmar and the WenChuan Earthquake in China (2008) and examined for content related to infant and young child feeding. Common messages identified included that: babies are vulnerable; stress prevents breastfeeding; and providing infant formula saves lives. Messages rarely reported included that: artificial feeding is dangerous; and breastfeeding protects infants. This analysis suggests that current patterns of media reporting may encourage harmful aid and increase child morbidity and mortality. Aid organisations should encourage the media to report accurately on the needs of infant and young children in emergencies so as to improve aid delivery.     

Aerostat-lofted instrument and sampling method for determination of emissions from open area sources

An aerostat-borne instrument and sampling method was developed to characterize air samples from area sources, such as emissions from open burning. The 10 kg battery-powered instrument system, termed “the Flyer”, is lofted with a helium-filled aerostat of 4 m nominal diameter and maneuvered by means of one or two tethers. The Flyer can be configured variously for continuous CO₂ monitoring, batch sampling of semi-volatile organic compounds (SVOCs), volatile organic compounds (VOCs), black carbon, metals, and PM by size. The samplers are controlled by a trigger circuit to avoid unnecessary dilution from background sampling when not within the source plume. The aerostat/Flyer method was demonstrated by sampling emissions from open burning (OB) and open detonation (OD) of military ordnance. A carbon balance approach was used to derive emission factors that showed excellent agreement with published values.     

The natural production of organobromine compounds

Organobromine chemicals are produced naturally by an array of biological and other chemical processes in our environment. Some of these compounds are identical to man-made organobromine compounds, such as methyl bromide, bromoform, and bromophenols, but many others are entirely new moleclar entities, often possessing extraordinary and important biological properties. Although only a few natural organobromine compounds had been discovered up to 1968, this number as of early 1999 is more than 1,600, and new examples are being discovered continually. Organobromine compounds are produced naturally by marine creatures (sponges, corals, sea slugs, tunicates, sea fans) and seaweed, plants, fungi, lichen, algae, bacteria, microbes, and some mammals. Many of these organobromine compounds are used in chemical defense, to facilitate food gathering, or as hormones.