The challenge of validating vulnerability estimates: the option of media content analysis for identifying drought-related crises

For an integrated assessment of the vulnerability of societies to drought it is necessary to set the benchmark at a level where the impacts of droughts lead to a state of affairs that departs from normal conditions, i.e. a crisis event. This article aims to improve the understanding of drought-related crisis events on the basis of a twofold media content analysis. This approach enables us to test when increased vulnerability in fact leads to a crisis situation and offers an improved understanding of the intensity and the extent of crisis events. To this end, we first outline our perspective on crisis and give an overview on existing approaches to identify crisis events. We then outline our two-step approach of media content analysis aimed at developing a crisis data set for the case study regions Andhra Pradesh (India), Southern Portugal and the Volga region (Russia). Using the Factiva news database and information by regional newspapers, a crisis data set is generated enabling us to define the occurrence and extent of drought-related crisis events in the case study regions. Moreover, based on attributes of drought impacts reported by news sources, we categorize the extensiveness of a specific drought. As a key result, our findings suggest that Southern Portugal, the case study region which is expected to be less susceptible to drought events than the other case study regions, faced the most extended crisis events.     

Treated wood in livestock facilities: relationships among residues of pentachlorophenol, dioxins, and furans in wood and beef.

Wood and other environmental samples were collected from sites that produced beef with higher than average residues of dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF). Analyses of these samples for PCDD/Fs and pentachlorophenol (PCP) indicated that the high beef residues were associated with PCP-treated wood in the animal facilities. Concentrations of PCDD/Fs in wood as toxic equivalents ranged from 10 to 320,000 pg/g. These concentrations were closely related to the concentrations of PCP, indicating that analysis for PCP provides an economical method to identify wood with high concentrations of PCDD/Fs. Further evidence for the PCP-treated wood as the source of the beef residues is provided by the similarity of the congener profiles in beef from the sites and those profiles predicted from the profiles in wood.     

Rat urinary metabolites from O,O-diethyl-O-(3,5,6-trichloro-2-pyridyl) phosphorothioate.

Rats metabolized single oral doses of O,O-diethyl-O(3,5,6-trichloro-2-pyridyl-2,6-14C) phosphorothioate to at least six radiolabeled urinary metabolites. The urine contained about 90 percent of the dose. Three of these metabolites were identified as the glucuronide of 3,5,6-trichloro-2-pyridinol (80% the urinary 14C), a glycoside of 3,5,6-trichloro-2-pyridinol (4%), and 3,5,6-trichloro-2-pyridinol (12%).     

Tissue distribution, excretion, and metabolism of 1,2,7,8-tetrachlorodibenzo-p-dioxin in the rat

A tissue distribution, excretion, and metabolism study was conducted using a relatively non-toxic dioxin congener, i.e., 1,2,7,8-tetrachlorodibenzo-p-dioxin (1278-TCDD), to gain a better understanding of mammalian metabolism of dioxins. Conventional, bile duct cannulated, and germ free male rats were administered mg/kg quantities as a single oral dose. Elimination of 1278-TCDD was largely complete by 72 h. Distribution of [¹⁴C]1278-TCDD was low in all tissues examined. Metabolites were identified in urine, bile, and feces by negative ion FAB-MS and ¹H-NMR, or GC/MS. The major fecal metabolite was a NIH-shifted hydroxylated TCDD. The bile contained a glucuronide conjugate of this hydroxy TCDD, and a diglucuronide conjugate of a dihydroxy-triCDD. The major metabolites in urine were glucuronide and sulfate conjugates of 4,5-dichlorocatechol.     

An investigation of the in vivo formation of octachlorodibenzo-p-dioxin

The in vivo formation of dioxins from chemical precursors was investigated in rats. Sprague-Dawley rats were fed pentachlorophenol or a predioxin in peanut oil for 14 days. Mass balance calculations indicated that pentachlorophenol was not converted to dioxins; however, the predioxin, nonachloro-2-phenoxyphenol, was converted to OCDD. Conversion of the predioxin ranged from 0.5% to 153% and depended on the amount of predioxin and OCDD present in the diet. The analytical procedures used for sample preparation did not appear to cause conversion of the predioxin to OCDD. The mechanism for biological conversion may be enzymatic or spontaneous.