Long term changes in polychlorodibenzo-p-dioxin concentrations in wood treated with technical pentachlorophenol

Wood samples treated with technical pentachlorophenol (PCP), technical sodium pentachlorophenoxide (NaPCP) and octachlorodibenzo-p-dioxin have been exposed outdoors for periods up to $\text{2}\text{1}\text{2}$ years. Analysis of extracts from the samples show that photolytic reductive dechlorination of highly chlorinated dibenzo-p-dioxins to less chlorinated isomers occurs. However there is no discernible increase in polychlorodibenzo-p-dioxin concentrations in the technical PCP treated wood presumably because further photolytic reactions and volatilisation compete effectively with the photolytic formation. There is no evidence for formation of octachlorodibenzo-p-dioxin (OCDD) in technical PCP treated wood in this study, probably because photolytic destruction and volatilisation compete effectively with formation reactions when the initial OCDD concentration is relatively high.     

Occurrence and persistence of perfluorooctanesulfonate and other perfluorinated surfactants in groundwater at a fire-training area at Wurtsmith Air Force Base,Michigan, USA

Various formulations of fire-extinguishing materials, including aqueous film-forming foams (AFFFs), were used as part of fire-training exercises conducted at Wurtsmith Air Force Base (WAFB) in northeastern Michigan from the 1950s until the base was decommissioned in 1993. As a result of past fire-training exercises, AFFF-laden wastewater containing fuels, solvents, and other materials directly entered groundwater without prior treatment. Perfluorinated surfactants are key components in some AFFF formulations. In this study, groundwater was analyzed for perfluoroalkanesulfonates and perfluorocarboxylates. Perfluoroalkanesulfonates were directly detected using negative-ion electrospray ionization mass spectrometry. Derivatized perfluorocarboxylates were detected using electron impact gas chromatography-mass spectrometry. Groundwater from wells around fire-training area FTA-02 at WAFB contained four perfluorinated surfactants ranging in concentration from 3 to 120 microg L(-1): perfluorooctanesulfonate (PFOS); perfluorohexanesulfonate; perfluorooctanoate; and perfluorohexanoate. This is the first report demonstrating that PFOS, recently shown to be toxic to organisms ranging from zooplankton to primates, is still present in groundwater in measurable quantities five or more years after its last known use.     

Forest health conditions in North America

Some of the greatest forest health impacts in North America are caused by invasive forest insects and pathogens (e.g., emerald ash borer and sudden oak death in the US), by severe outbreaks of native pests (e.g., mountain pine beetle in Canada), and fires exacerbated by changing climate. Ozone and N and S pollutants continue to impact the health of forests in several regions of North America. Long-term monitoring of forest health indicators has facilitated the assessment of forest health and sustainability in North America. By linking a nationwide network of forest health plots with the more extensive forest inventory, forest health experts in the US have evaluated current trends for major forest health indicators and developed assessments of future risks. Canada and Mexico currently lack nationwide networks of forest health plots. Development and expansion of these networks is critical to effective assessment of future forest health impacts.     

WATER USE DATA – WHO NEEDS IT?1

ABSTRACT: This paper addresses problems in the design of a water use data base and valuation of water use data. An examination of the economic efficiency and distributional aspects of selected water management problems indicates that there are benefits to be obtained from water use information and, thus, there is a potential value to water use data. Water use information is viewed as being produced by combining water use data with other data in a modeling context suggested by theory relevant to the problem at hand, and a well designed water use data base will facilitate this synthesis. Data “needs” in the production of water use information via economic modeling are described to illustrate the relationship between theory and data. Some of the desirable characteristics of a water use data base and inadequacies of the existing water use data “base” are described. The fugitive nature of the water use data resource and a lack of understanding of both the information “production function” and the role of water use information in decisionmaking complicates the water use data valuation problem.