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This progress report summarizes the research and development activities conducted in the Environmental Sciences Division of Oak Ridge National Laboratory during fiscal year (FY) 1992, which which extended from October 1, 1991, through September 30, 1992. This report is structured to provide descriptions of current activities and accomplishments in each of the division`s major organizational units. Section activities are described in the Earth and Atmospheric sciences, ecosystem studies, Environmental analysis, environmental biotechnology, and division operations.

A detailed method of patient skin self examination for the dysplastic naevus syndrome using full-scale colour total body photographs is described. The patient and the physician share the same set of photographs to monitor the syndrome. Any new lesions or changing lesions are reported by the patient to the physician for further evaluation. This method has an advantage over previous recommendations because patient use of the photographs provides an objective visual baseline for comparison. Overall costs of caring for patients with the dysplastic naevus syndrome through this method are likely to decrease since biopsies can be limited to new lesions or lesions demonstrating a changing pattern.

A method of full-scale colour total body photography for the management of patients with the dysplastic naevus syndrome is presented. These photographs are indexed for easy use and require no special equipment for viewing. Controversy about the use of clinical photography for the management of the dysplastic naevus syndrome is reviewed.

In this work we will discuss three cutaneous markers of systemic disease. Acanthosis nigricans is the most widely known in this category. Cutaneous angiokeratomas are usually associated with enzyme defect disorders, such as Fabry's disease, and are linked in this work as a reactive pattern in hepatorenal failure. Mast cell disease may occur in a number of forms, often with systemic involvement.

We evaluated 18,014 patients who underwent allogeneic bone marrow transplantation (BMT) at 235 centers worldwide to examine the incidence of and risk factors for posttransplant lymphoproliferative disorders (PTLD). PTLD developed in 78 recipients, with 64 cases occurring less than 1 year after transplantation. The cumulative incidence of PTLD was 1.0% +/- 0.3% at 10 years. Incidence was highest 1 to 5 months posttransplant (120 cases/10,000 patients/yr) followed by a steep decline to less than 5/10,000/yr among/=1-year survivors. In multivariate analyses, risk of early-onset PTLD (1 year) was strongly associated (P.0001) with unrelated or human leukocyte antigen (HLA) mismatched related donor (relative risk [RR] = 4.1), T-cell depletion of donor marrow (RR = 12.7), and use of antithymocyte globulin (RR = 6.4) or anti-CD3 monoclonal antibody (RR = 43.2) for prophylaxis or treatment of acute graft-versus-host disease (GVHD). There was a weaker association with the occurrence of acute GVHD grades II to IV (RR = 1.9, P =.02) and with conditioning regimens that included radiation (RR = 2.9, P =.02). Methods of T-cell depletion that selectively targeted T cells or T plus natural killer (NK) cells were associated with markedly higher risks of PTLD than methods that removed both T and B cells, such as the CAMPATH-1 monoclonal antibody or elutriation (P =.009). The only risk factor identified for late-onset PTLD was extensive chronic GVHD (RR = 4.0, P =.01). Rates of PTLD among patients with 2 or/=3 major risk factors were 8.0% +/- 2.9% and 22% +/- 17.9%, respectively. We conclude that factors associated with altered immunity and T-cell regulatory mechanisms are predictors of both early- and late-onset PTLD.

Benzoic acid (BA) was used to induce nonimmunologic contact irritation in 10 younger (23-47 years old) and 5 older (72-90 years old) healthy volunteers. BA 2.5% in petrolatum was applied to 8 locations on the face, neck and volar forearm. Changes in the skin blood flow were monitored using a laser Doppler flowmeter. Also measured at each location were baseline measurements of skin blood flow, transepidermal water loss, stratum corneum hydration, skin surface temperature and skin surface pH.The neck area exhibited the greatest reaction in both age groups while the forearm exhibited the least. At each site tested, the younger group consistently demonstrated greater reactivity to BA. A significant correlation was noted between stratum corneum hydration and irritation.This information provides a basis to further study the frequent poorly understood intolerance of the face to topical formulation.

Several articles have been published that carefully describe techniques for obtaining reliable photographic series of patients with the atypical mole syndrome. Four common methods of total body photography are described. Follow-up studies of the effectiveness of photodocumentation for patients with the atypical mole syndrome are reviewed.

Sulfate sulfur concentrations and pH of precipitation and streamflow, and sulfur concentrations of biomass and soil components, were determined for a 97.5-ha mixed deciduous forest (Walker Branch Watershed) in eastern Tennessee. Amounts of sulfur (S) added by precipitation and lost by streamflow were compared to fluxes of S between biomass pools. Approximately 18.1 kg/ha per year entered the watershed from the atmosphere, while only 11.5 kg/ha per year were lost in streamflow. Analysis of biomass and soil concentrations of S indicate that, of the 6.6 kg/ha per year apparent accumulation of S for the watershed as a whole, 8.6 kg accrue to mineral soil while 4.3 kg are lost from organic soil horizons, and 2.3 kg accrue to annual increment of vegetation. Seasonal variations in S input and export from the watershed were closely tied to precipitation events. The weighted mean pH of the rainfall samples collected at five sampling sites on the watershed was pH 4.2. Sulfate accounts for 80% of major anions (millequivalent basis) contributed to the watershed. The behavior of S on Walker Branch Watershed appears to differ significantly from locations in the northeastern US, however the data suggest active expansion to the southeastern US of themore » area impacted by atmospheric sulfate pollution commonly associated with the northeastern region of the US.« less

Wind-blown rain, rain splash, and films of free moisture play important roles in the epidemiology of many plant diseases. The effects of simulated rain acidified with sulfuric acid were studied on several host-parasite systems. Plants were exposed in greenhouse or field to simulated rain of pH 3.2 ± 0.1 or pH 6.0 ± 0.2. Simulated ‘rain’ of pH 3.2 resulted in: (1) an 86% inhibition in telia production of Cronartium fusiforme on Quercus phellos; (2) a 66% inhibition of reproduction of Meloidogyne hapla on field-grown Phaseolus vulgaris; (3) a 10% decrease in the severity of Uromyces phaseoli on field-grown Phaseolus vulgaris; and (4) an inhibition of Rhizobium nodulation of Phaseolus vulgaris and Glycine max by an average of 73%. Effects on halo blight of kidney bean (caused by Pseudomonas phaseolicola) depended upon the segment of the disease cycle in which the ‘rain’ occurred: (a) simulated rain of pH 3.2 applied to plants before inoculation stimulated disease development; (b) suspension of inoculum in ‘rain’ of pH 3.2 decreased inoculum potential; and (c) ‘rain’ of pH 3.2 applied to plants after infection inhibited disease development. Scanning electron microscopy of epicuticular waxes on leaves of Quercus phellos and Phaseolus vulgaris showed marked erosion of those surfaces by ‘rain’ of pH 3.2, indicating possible influences on the structure and function of plant cuticles. These results suggest that the acidity of rain is a new parameter of environmental concern, and underline the need for study of the consequences of prolonged exposure of both agronomic and natural ecosystems to this stress factor.

During 1982-1984, experiments regarding the nature of crop responses to combinations of acid rain and gaseous pollutant treatments were conducted. Open-top field chambers were used in conjunction with an automatic rain exclusion-simulant distribution system to expose crops to controlled levels of gaseous pollutants and rain acidity in a field setting. Rain exclusion was achieved by automatically moving covers over the experimental plots at the onset of a rain event. The simulant distribution system was automatically activated after 0.25 mm of rain was collected in a recording rain gauge located adjacent to the experimental plots. Rain simulants were dispensed through nozzles until the amount deposited within the plot equaled that deposited by the natural rain outside the plot. The system was capable of dispensing rain simulants with three levels of acidity to ambient air plots and to charcoalfiltered and nonfiltered-air chambered plots. The ability to automatically dispense rain simulants during, and in e...

Sulfur (S) cycling in a chestnut oak forest on Walker Branch Watershed, Tennessee, was dominated by geochemical processes involving sulfate. Even though available SO 42- was present far in excess of forest nutritional requirements, the ecosystem as a whole accumulated ∼60% of incoming SO4-S. Most (90%) of this accumulation occurred by SO 42- adsorption in sesquioxide-rich subsurface soils, with a relatively minor amount accumulating and cycling as SO 42- within vegetative components. Organic sulfates are thought to constitute a large proportion of total S in surface soils, also, and to provide a pool of readily mineralized available S within the ecosystem.

M. Alexander’s paper was an overview of the effects of acidity on micro-organisms and microbial processes. He reported that microbiologists have long been interested in effects of acidity, and that there is an enormous literature on the subject. He began the review by listing the six major microbial groups in soil (bacteria, fungi, actinomycetes, protozoa, algae, and viruses) and their essential functions.

Deposition of materials from the atmosphere onto the earth’s surface involves many complicated processes. Gases, liquids, and solids are deposited over time periods of minutes to months after they are placed into the atmosphere. Once airborne, matter can change its chemical and physical characteristics. Constituents in rain that confer acidity such as H+, NO3 −, and SO4 2−, as well as gaseous pollutants such as O3, SO2, and NOX are of concern because they may have affected ecosystems in North America and Europe.

Wind-blown rain, rain splash, and films of free moisture play important roles in the epidemiology of many plant diseases. The chemical nature of the aqueous microenvironment at the infection court is a potentially significant factor in the successful dissemination, establishment, and survival of plant pathogenic microorganisms. Acidic rainfall has a potential for influencing not only the pathogen, but also the host organism, and the host-pathogen complex. Although host-pathogen interactions add a degree of complexity to the study of abiotic environmental stress of plants, it is our hope, through the use of a combination of general concepts, theoretical postulations, and experimental data, to describe the potential role that rainfall acidity may play in the often subtle balance between populations of plants and populations of plant pathogens.

Above-ground surfaces of higher plants are the site of deposition of a variety of airborne biological materials and atmospheric pollutants. These biological materials (pollen, fungal spores, bacterial cells, waste from insect feeding) and the pollutants (as aerosols, gases, or dissolved in rain) may interact to influence the host plant, the pathogen, or the host/pathogen association. The conditions of the plant’s surface environments can affect the behavior of a pathogen and alter the chemical characteristics of throughfall or stemflow originating at those surfaces. Host-pathogen interactions represent a sensitive indicator of plant stress, since the changes in balance between host and parasite may reveal a subtle abiotic stress long before the response would be detectable in the healthy plant alone. The impact of wet and dry deposition of pollutant materials on the plant surface alone, and on potentially pathogenic organisms, is necessary in order to fully interpret many plant:parasite interactions. This paper discusses examples of pollutant-parasite interactions at the leaf surface to illustrate the role that pollutants can play in the relationship of susceptible host and virulent pathogen.

Greenhouse, growth chamber, and field experiments were conducted to determine the response of crop plants to levels of acidity in simulated rain. The major objectives of this research effort were: (1) to determine the levels of acidity in rain that alter crop productivity, (2) to evaluate varietal differences in crop response, and (3) to determine the response of crop plants to the combined stress of acid rain and gaseous pollutants [primarily ozone (O3)]. In the greenhouse, plants were exposed to either four or six levels of acidity twice per week with a rain simulator. In the growth chamber experiments, gaseous pollutant fumigations were conducted either once or three times weekly with a continuously stirred tank reactor exposure system. In the field, open-top field chambers were used in conjunction with an automatic rain exclusion-simulant distribution system to expose crops to controlled levels of gaseous pollutants and rain acidity. In an experiment with tomato cultivars, pH 2.3 rain applied to both foliage and soil reduced growth, while the same solution applied to the soil without foliar contact increased growth. The growth response of radish and alfalfa plants to the combined stress of acid rain and ozone was additive. The visible injury response of younger radish leaves to combinations that included pH 3.3 rain and 0.2 and 0.4 ppm of O3 was less than additive. In field studies, Davis soybeans snowed no significant growth or yield responses to ambient O3 levels, or simulated rain at pH 5.2, 4.2 or 3.2. There was a small (−3%) rain treatment (pH) effect on weight per seed in the pH 4.2 simulated rain and the ambient rain treatments (also ~pH 4.2).