Occurrence of perfluorinated organic acids in the North and Baltic Seas. Part 2: distribution in sediments

Purpose  

The distribution of polar perfluorinated compounds (PFCs) in sea water of the North and Baltic Seas has been described in part 1 of this study. In part 2, their occurrence in sediments is described in order to further investigate their distribution routes and possible sinks.     

Biochar pyrolyzed at two temperatures affects Escherichia coli transport through a sandy soil

The incorporation of biochar into soils has been proposed as a means to sequester carbon from the atmosphere. An added environmental benefit is that biochar has also been shown to increase soil retention of nutrients, heavy metals, and pesticides. The goal of this study was to evaluate whether biochar amendments affect the transport of Escherichia coli through a water-saturated soil. We looked at the transport of three E. coli isolates through 10-cm columns packed with a fine sandy soil amended with 2 or 10% (w/w) poultry litter biochar pyrolyzed at 350 or 700°C. For all three isolates, mixing the high-temperature biochar at a rate of 2% into the soil had no impact on transport behavior. When added at a rate of 10%, a reduction of five orders of magnitude in the amount of E. coli transported through the soil was observed for two of the isolates, and a 60% reduction was observed for the third isolate. Mixing the low-temperature biochar into the soil resulted in enhanced transport through the soil for two of the isolates, whereas no significant differences in transport behavior were observed between the low-temperature and high-temperature biochar amendments for one isolate. Our results show that the addition of biochar can affect the retention and transport behavior of E. coli and that biochar application rate, biochar pyrolysis temperature, and bacterial surface characteristics were important factors determining the transport of E. coli through our test soil.     

II. Incidence of Acute Respiratory Illness

A study of acute respiratory illness was conducted from November 1968 through April 1969 among families residing in an area of relatively high nitrogen dioxide exposure, in an area of elevated suspended particulate exposure, and in two control areas of Greater Chattanooga. Respiratory illness rates were consistently higher in all family segments in the high-nitrogen dioxide exposure area when rates were averaged for the entire 24 weeks of study, the A₂/Hong-Kong epidemic period, or post-epidemic interval. A relative excess in respiratory illness of 18.8 percent was found among families exposed to elevated NO₂ concentrations and an excess of 10.4 percent was found among families in the elevated-suspended particulate exposure area.     

Cost and Benefits of Road Dust Control in Seattle’s Industrial Valley

The paving of gravel roads with an average daily traffic (ADT) over 15 is a least cost method for reducing suspended particulate In the air in Seattle. It is also a good business investment when the ADT exceeds 100. Clean roads, gutters, and parking lots may reduce or eliminate Seattle’s most serious environmental constraint on economic development. In a study done in Seattle’s Duwamish Valley the impact of road dust on air quality was measured by obtaining dust emission factors for vehicles traveling at 10, 20, and 30 mph on gravel as well as dusty paved roads. A University of Washington Mark II Cascade Impactor was mounted on a trailer and towed behind a car to determine the concentration and size distribution of this dust. It was found that each vehicle mile at 20 mph on unpaved roads contributed 7.0 Ib of dust to the air, 1.9 Ib consisting of particles smaller than 10 microns in diameter and 0.24 Ib below 2 microns. Three to eight percent by weight of this respirable dust was free silica, which is potentially toxic. The quantity of dust generated varies as an exponent of the speed. The concentrations of dust found in the air near a dry gravel road with an ADT of 250 reached 584 μg/m3 for an 8 hr work day. A 24 hr suspended particulate reading of 463 μg/m3 total and 3.83 μg/m3 free silica was found beside a dusty paved road with an ADT of 18,000. Nineteen miles of gravel roads and 110 miles of dusty paved roads contributed 2700 tons/year of particulate, of which 700 tons were below 10 microns. Paving or oiling such roads will produce benefits of $3,881,000 yearly in household cleaning, health care, sewer, vehicle operation, and road maintenance costs as well as an increase in property values. Clean roads can lower the cost of clean air in Seattle.     

Simultaneous Control of Hg0, SO2, and NOx by Novel Oxidized Calcium-Based Sorbents

Abstract

Efforts to develop multipollutant control strategies have demonstrated that adding certain oxidants to different classes of Ca-based sorbents leads to a significant improvement in elemental Hg vapor (Hg⁰), SO₂, and NO_x removal from simulated flue gases. In the study presented here, two classes of Ca-based sorbents (hydrated limes and silicate compounds) were investigated. A number of oxidizing additives at different concentrations were used in the Ca-based sorbent production process. The Hg⁰, SO₂, and NO_x capture capacities of these oxidant-enriched sorbents were evaluated and compared to those of a commercially available activated carbon in bench-scale, fixed-bed, and fluid-bed systems. Calcium-based sorbents prepared with two oxidants, designated C and M, exhibited Hg⁰ sorp-tion capacities (~100 μg/g) comparable to that of the activated carbon; they showed far superior SO₂ and NO_x sorption capacities. Preliminary cost estimates for the process utilizing these novel sorbents indicate potential for substantial lowering of control costs, as compared with other processes currently used or considered for control of Hg⁰, SO₂, and NO_x emissions from coal-fired boilers. The implications of these findings toward development of multipollutant control technologies and planned pilot and field evaluations of more promising multipollutant sorbents are summarily discussed.     

Managing climate change impacts to enhance the resilience and sustainability of Fennoscandian forests

Projected warming in Sweden and other Fennoscandian countries will probably increase growth rates of forest trees near their northern limits, increase the probability of new pest outbreaks, and foster northerly migration of both native and exotic species. The greatest challenges for sustainable forestry are to restore and enhance the ecological and socioeconomic diversity of intensively managed forested landscapes. With appropriate management, climate warming may facilitate the regeneration of this diversity. Experimental transplant gardens along latitudinal or altitudinal gradients and high-resolution maps of expected future climate could provide a scientific basis for predicting the climate response of potential migrant species. Management of corridors and assisted migration could speed the movement of appropriate species.     

Methylsulfonyl PCB and DDE metabolites and their enantioselective gas chromatographic separation in human adipose tissues, seal blubber and pelican muscle

In the present investigation, eleven human adipose tissue samples, two seal blubber samples and two pelican muscles samples were analyzed with regard to their concentrations of PCB parent compounds as well as to the respective chiral methylsulfonyl metabolites 3-MeSO2-CB 91, 4-MeSO2-CB 91, 3-MeSO2-CB 95, 4-MeSO2-CB 95, 3-MeSO2-CB 149, 4-MeSO2-CB 149, 3-MeSO2-CB 132, 4-MeSO2-CB 132, 3-MeSO2-CB 174, and 4-MeSO2-CB 174 and the achiral metabolites 3-MeSO2-CB 49, 4-MeSO2-CB 49, 3-MeSO2-CB 101, 4-MeSO2-CB 101, 3-MeSO2-CB 110, 4-MeSO2-CB 110 and 3-MeSO2-DDE. In order to verify enantioselective transformation processes and to compare the different enzymatic transformation pathways in birds and mammals, the enantioselective excesses of the chiral PCB-metabolites were determined by enantioselective gas chromatography with electron capture and mass spectrometric detection using modified cyclodextrin phases, including heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl-)-beta-cyclodextrin/OV1701 (1:1) for the parent PCBs and heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl-)-beta-cyclodextrin/SE52 (1:4) for the metabolites, respectively.