Search

Understanding metal scavenging by calcite in deep aquifers in granite is of importance for deciphering and modeling hydrochemical fluctuations and water-rock interaction in the upper crust and for retention mechanisms associated with underground repositories for toxic wastes. Metal scavenging into calcite has generally been established in the laboratory or in natural environments that cannot be unreservedly applied to conditions in deep crystalline rocks, an environment of broad interest for nuclear waste repositories. Here, we report a microanalytical study of calcite precipitated over a period of 17 years from anoxic, low-temperature (14 °C), neutral (pH: 7.4-7.7), and brackish (Cl: 1700-7100 mg/L) groundwater flowing in fractures at >400 m depth in granite rock. This enabled assessment of the trace metal uptake by calcite under these deep-seated conditions. Aquatic speciation modeling was carried out to assess influence of metal complexation on the partitioning into calcite. The resulting environment-specific partition coefficients were for several divalent ions in line with values obtained in controlled laboratory experiments, whereas for several other ions they differed substantially. High absolute uptake of rare earth elements and U(IV) suggests that coprecipitation into calcite can be an important sink for these metals and analogousactinides in the vicinity of geological repositories.

The toxicity of arsenic (As) towards life on Earth is apparent in the dense distribution of genes associated with As detoxification across the tree of life. The ability to defend against As is particularly vital for survival in As-rich shallow submarine hydrothermal ecosystems along the Hellenic Volcanic Arc (HVA), where life is exposed to hydrothermal fluids containing up to 3000 times more As than present in seawater. We propose that the removal of dissolved As and phosphorus (P) by sulfide and Fe(III)(oxyhydr)oxide minerals during sediment-seawater interaction, produces nutrient-deficient porewaters containing < 2.0 ppb P. The porewater arsenite-As(III) to arsenate-As(V) ratios, combined with sulfide concentration in the sediment and/or porewater, suggest a hydrothermally-induced seafloor redox gradient. This gradient overlaps with changing high affinity phosphate uptake gene abundance. High affinity phosphate uptake and As cycling genes are depleted in the sulfide-rich settings, relative to the more oxidizing habitats where mainly Fe(III)(oxyhydr)oxides are precipitated. In addition, a habitat-wide low As-respiring and As-oxidizing gene content relative to As resistance gene richness, suggests that As detoxification is prioritized over metabolic As cycling in the sediments. Collectively, the data point to redox control on Fe and S mineralization as a decisive factor in the regulation of high affinity phosphate uptake and As cycling gene content in shallow submarine hydrothermal ecosystems along the HVA.

The seafloor sediments of Spathi Bay, Milos Island, Greece, are part of the largest arsenic-CO 2 -rich shallow submarine hydrothermal ecosystem on Earth. Here, white and brown deposits cap chemically distinct sediments with varying hydrothermal influence. All sediments contain abundant genes for autotrophic carbon fixation used in the Calvin-Benson-Bassham (CBB) and reverse tricaboxylic acid (rTCA) cycles. Both forms of RuBisCO, together with ATP citrate lyase genes in the rTCA cycle, increase with distance from the active hydrothermal centres and decrease with sediment depth. Clustering of RuBisCO Form II with a highly prevalent Zetaproteobacteria 16S rRNA gene density infers that iron-oxidizing bacteria contribute significantly to the sediment CBB cycle gene content. Three clusters form from different microbial guilds, each one encompassing one gene involved in CO 2 fixation, aside from sulfate reduction. Our study suggests that the microbially mediated CBB cycle drives carbon fixation in the Spathi Bay sediments that are characterized by diffuse hydrothermal activity, high CO 2 , As emissions and chemically reduced fluids. This study highlights the breadth of conditions influencing the biogeochemistry in shallow CO 2 -rich hydrothermal systems and the importance of coupling highly specific process indicators to elucidate the complexity of carbon cycling in these ecosystems.

The deep biosphere is one of the least understood ecosystems on Earth. Although most microbiological studies in this system have focused on prokaryotes and neglected microeukaryotes, recent discoveries have revealed existence of fossil and active fungi in marine sediments and sub-seafloor basalts, with proposed importance for the subsurface energy cycle. However, studies of fungi in deep continental crystalline rocks are surprisingly few. Consequently, the characteristics and processes of fungi and fungus-prokaryote interactions in this vast environment remain enigmatic. Here we report the first findings of partly organically preserved and partly mineralized fungi at great depth in fractured crystalline rock (-740 m). Based on environmental parameters and mineralogy the fungi are interpreted as anaerobic. Synchrotron-based techniques and stable isotope microanalysis confirm a coupling between the fungi and sulfate reducing bacteria. The cryptoendolithic fungi have significantly weathered neighboring zeolite crystals and thus have implications for storage of toxic wastes using zeolite barriers.Deep subsurface microorganisms play an important role in nutrient cycling, yet little is known about deep continental fungal communities. Here, the authors show organically preserved and partly mineralized fungi at 740 m depth, and find evidence of an anaerobic fungi and sulfate reducing bacteria consortium.

The surface waters at the ultramafic ophiolitic outcrop in Chimaera, Turkey, are characterized by high pH values and high metal levels due to the percolation of fluids through areas of active serpentinization. We describe the influence of the liquid chemistry, mineralogy, and H 2 and CH 4 levels on the bacterial community structure in a semidry, exposed, ultramafic environment. The bacterial and archaeal community structures were monitored using Illumina sequencing targeting the 16S rRNA gene. At all sampling points, four phyla, Proteobacteria , Actinobacteria , Chloroflexi , and Acidobacteria , accounted for the majority of taxa. Members of the Chloroflexi phylum dominated low-diversity sites, whereas Proteobacteria dominated high-diversity sites. Methane, nitrogen, iron, and hydrogen oxidizers were detected as well as archaea and metal-resistant bacteria. IMPORTANCE Our study is a comprehensive microbial investigation of the Chimaera ophiolite. DNA has been extracted from 16 sites in the area and has been studied from microbial and geochemical points of view. We describe a microbial community structure that is dependent on terrestrial, serpentinization-driven abiotic H 2 , which is poorly studied due to the rarity of these environments on Earth., (Copyright © 2017 Neubeck et al.)

Fungi have recently been found to comprise a significant part of the deep biosphere in oceanic sediments and crustal rocks. Fossils occupying fractures and pores in Phanerozoic volcanics indicate that this habitat is at least 400 million years old, but its origin may be considerably older. A 2.4-billion-year-old basalt from the Palaeoproterozoic Ongeluk Formation in South Africa contains filamentous fossils in vesicles and fractures. The filaments form mycelium-like structures growing from a basal film attached to the internal rock surfaces. Filaments branch and anastomose, touch and entangle each other. They are indistinguishable from mycelial fossils found in similar deep-biosphere habitats in the Phanerozoic, where they are attributed to fungi on the basis of chemical and morphological similarities to living fungi. The Ongeluk fossils, however, are two to three times older than current age estimates of the fungal clade. Unless they represent an unknown branch of fungus-like organisms, the fossils imply that the fungal clade is considerably older than previously thought, and that fungal origin and early evolution may lie in the oceanic deep biosphere rather than on land. The Ongeluk discovery suggests that life has inhabited submarine volcanics for more than 2.4 billion years.

We have after half a century of coordinated scientific drilling gained insight into Earth´s largest microbial habitat, the subseafloor igneous crust, but still lack substantial understanding regarding its abundance, diversity and ecology. Here we describe a fossilized microbial consortium of prokaryotes and fungi at the basalt-zeolite interface of fractured subseafloor basalts from a depth of 240 m below seafloor (mbsf). The microbial consortium and its relationship with the surrounding physical environment are revealed by synchrotron-based X-ray tomographic microscopy (SRXTM), environmental scanning electron microscopy (ESEM), and Raman spectroscopy. The base of the consortium is represented by microstromatolites-remains of bacterial communities that oxidized reduced iron directly from the basalt. The microstromatolites and the surrounding basalt were overlaid by fungal cells and hyphae. The consortium was overgrown by hydrothermally formed zeolites but remained alive and active during this event. After its formation, fungal hyphae bored in the zeolite, producing millimetre-long tunnels through the mineral substrate. The dissolution could either serve to extract metals like Ca, Na and K essential for fungal growth and metabolism, or be a response to environmental stress owing to the mineral overgrowth. Our results show how microbial life may be maintained in a nutrient-poor and extreme environment by close ecological interplay and reveal an effective strategy for nutrient extraction from minerals. The prokaryotic portion of the consortium served as a carbon source for the eukaryotic portion. Such an approach may be a prerequisite for prokaryotic-eukaryotic colonisation of, and persistence in, subseafloor igneous crust.

Fungi have been recognized as a frequent colonizer of subseafloor basalt but a substantial understanding of their abundance, diversity and ecological role in this environment is still lacking. Here we report fossilized cryptoendolithic fungal communities represented by mainly Zygomycetes and minor Ascomycetes in vesicles of dredged volcanic rocks (basanites) from the Vesteris Seamount in the Greenland Basin. Zygomycetes had not been reported from subseafloor basalt previously. Different stages in zygospore formation are documented in the studied samples, representing a reproduction cycle. Spore structures of both Zygomycetes and Ascomycetes are mineralized by romanechite-like Mn oxide phases, indicating an involvement in Mn(II) oxidation to form Mn(III,VI) oxides. Zygospores still exhibit a core of carbonaceous matter due to their resistance to degradation. The fungi are closely associated with fossiliferous marine sediments that have been introduced into the vesicles. At the contact to sediment infillings, fungi produced haustoria that penetrated and scavenged on the remains of fragmented marine organisms. It is most likely that such marine debris is the main carbon source for fungi in shallow volcanic rocks, which favored the establishment of vital colonies.

The deep biosphere of the subseafloor basalts is recognized as a major scientific frontier in disciplines like biology, geology, and oceanography. Recently, the presence of fungi in these environments has involved a change of view regarding diversity and ecology. Here, we describe fossilized fungal communities in vugs in subseafloor basalts from a depth of 936.65 metres below seafloor at the Detroit Seamount, Pacific Ocean. These fungal communities are closely associated with botryoidal Mn oxides composed of todorokite. Analyses of the Mn oxides by Electron Paramagnetic Resonance spectroscopy (EPR) indicate a biogenic signature. We suggest, based on mineralogical, morphological and EPR data, a biological origin of the botryoidal Mn oxides. Our results show that fungi are involved in Mn cycling at great depths in the seafloor and we introduce EPR as a means to easily identify biogenic Mn oxides in these environments.

Precipitation of exceptionally 13C-depleted authigenic carbonate is a result of, and thus a tracer for, sulphate-dependent anaerobic methane oxidation, particularly in marine sediments. Although these carbonates typically are less depleted in 13C than in the source methane, because of incorporation of C also from other sources, they are far more depleted in 13C (δ13C as light as -69‰ V-PDB) than in carbonates formed where no methane is involved. Here we show that oxidation of biogenic methane in carbon-poor deep groundwater in fractured granitoid rocks has resulted in fracture-wall precipitation of the most extremely 13C-depleted carbonates ever reported, δ13C down to -125‰ V-PDB. A microbial consortium of sulphate reducers and methane oxidizers has been involved, as revealed by biomarker signatures in the carbonates and S-isotope compositions of co-genetic sulphide. Methane formed at shallow depths has been oxidized at several hundred metres depth at the transition to a deep-seated sulphate-rich saline water. This process is so far an unrecognized terrestrial sink of methane.

Impacts are common geologic features on the terrestrial planets throughout the solar system, and on at least Earth and Mars impacts have induced hydrothermal convection. Impact-generated hydrothermal systems have been suggested to possess the same life supporting capability as hydrothermal systems associated with volcanic activity. However, evidence of fossil microbial colonization in impact-generated hydrothermal systems is scarce in the literature. Here we report of fossilized microorganisms in association with cavity-grown hydrothermal minerals from the 458 Ma Lockne impact structure, Sweden. Based on morphological characteristics the fossilized microorganisms are interpreted as fungi. We further infer the kerogenization of the microfossils, and thus the life span of the fungi, to be contemporaneous with the hydrothermal activity and migration of hydrocarbons in the system. Our results from the Lockne impact structure show that hydrothermal systems associated with impact structures can support colonization by microbial life.

Debates on the formation of banded iron formations in ancient ferruginous oceans are dominated by a dichotomy between abiotic and biotic iron cycling. This is fuelled by difficulties in unravelling the exact processes involved in their formation. Here we provide fossil environmental evidence for anoxygenic photoferrotrophic deposition of analogue banded iron rocks in shallow marine waters associated with an Early Quaternary hydrothermal vent field on Milos Island, Greece. Trace metal, major and rare earth elemental compositions suggest that the deposited rocks closely resemble banded iron formations of Precambrian origin. Well-preserved microbial fossils in combination with chemical data imply that band formation was linked to periodic massive encrustation of anoxygenic phototrophic biofilms by iron oxyhydroxide alternating with abiotic silica precipitation. The data implicate cyclic anoxygenic photoferrotrophy and their fossilization mechanisms in the construction of microskeletal fabrics that result in the formation of characteristic banded iron formation bands of varying silica and iron oxide ratios.

We report the discovery of fossilized filamentous structures in samples of the lithified, volcaniclastic apron of Gran Canaria, which were obtained during Leg 157 of the Ocean Drilling Program (ODP). These filamentous structures are 2-15 μm in diameter and several hundred micrometers in length and are composed of Si, Al, Fe, Ca, Mg, Na, Ti, and C. Chitin was detected in the filamentous structures by staining with wheat germ agglutinin dye conjugated with fluorescein isothiocyanate (WGA-FITC), which suggests that they are fossilized fungal hyphae. The further elucidation of typical filamentous fungal morphological features, such as septa, hyphal bridges, and anastomosis and their respective sizes, support this interpretation. Characteristic structures that we interpreted as fossilized spores were also observed in association with the putative hyphae. The fungal hyphae were found in pyroxene phenocrysts and in siderite pseudomorphs of a basalt breccia. The fungal colonization of the basalt clasts occurred after the brecciation but prior to the final emplacement and lithification of the sediment at ∼16-14 Ma. The siderite appears to have been partially dissolved by the presence of fungal hyphae, and the fungi preferentially colonized Fe-rich carbonates over Fe-poor carbonates (aragonite). Our findings indicate that fungi may be an important geobiological agent in subseafloor environments and an important component of the deep subseafloor biosphere, and that hydrothermal environments associated with volcanism can support a diverse ecosystem, including eukaryotes.

Chromite is a mineral with low solubility and is thus resistant to dissolution. The exception is when manganese oxides are available, since they are the only known naturally occurring oxidants for chromite. In the presence of Mn(IV) oxides, Cr(III) will oxidise to Cr(VI), which is more soluble than Cr(III), and thus easier to be removed. Here we report of chromite phenocrysts that are replaced by rhodochrosite (Mn(II) carbonate) in subseafloor basalts from the Koko Seamount, Pacific Ocean, that were drilled and collected during the Ocean Drilling Program (ODP) Leg 197. The mineral succession chromite-rhodochrosite-saponite in the phenocrysts is interpreted as the result of chromite oxidation by manganese oxides. Putative fossilized microorganisms are abundant in the rhodochrosite and we suggest that the oxidation of chromite has been mediated by microbial activity. It has previously been shown in soils and in laboratory experiments that chromium oxidation is indirectly mediated by microbial formation of manganese oxides. Here we suggest a similar process in subseafloor basalts.

One of the key-principles of the iron-sulphur world theory is to bring organic molecules close enough to interact with each other, using the surface of pyrite as a substrate in a hydrothermal setting. The present paper explores the relationship of pyrite and organic matter in a hydrothermal setting from the geological record; in hydrothermal calcite veins from Carboniferous limestones in central Ireland. Here, the organic matter is accumulated as coatings around, and through, pyrite grains. Most of the pyrite grains are euhedral-subhedral crystals, ranging in size from ca 0.1-0.5 mm in diameter, and they are scattered throughout the matrix of the vein calcite. The organic matter was deposited from a hydrothermal fluid at a temperature of at least 200°C, and gives a Raman signature of disordered carbon. This study points to an example from a hydrothermal setting in the geological record, demonstrating that pyrite can have a high potential for the concentration and accumulation of organic materials.

Purpose: Depressive symptomatology during pregnancy has been associated with negative health outcomes for both the mother and child. This study examines the potential associations between depression and depressive symptoms in poor women and African-American women and their lifelong experiences of discrimination., Methods: Data from 2,731 African-American and White participants in the Pregnancy Outcomes and Community Health Study were analyzed. Multiple regression analyses were used to investigate relations between depressive symptoms and total discrimination, and between depressive symptoms and 3 discrimination types (gender, race, and socioeconomic)., Main Findings: Initial results showed that African-American women had higher levels of depressive symptoms than White women. Self-reported total discrimination and discrimination types were each positively associated with depressive symptomatology in all women. After adjusting for sociodemographic characteristics (maternal age, education, employment status, partner status, and Medicaid status) and examining significant interactions, the race difference in depressive symptomatology was evident only in employed women. The addition of total discrimination to the multicovariate model eliminated race differences in the adjusted mean level of depressive symptoms. When the 3 discrimination types were modeled simultaneously with all other covariates, only gender and economic discrimination remained positively associated with depressive symptoms in African-American and White women., Conclusions: These results should be cautiously interpreted because of 1) the study design--namely, ascertainment of maternal discrimination and depressive symptoms at a single time point; and 2) limitations of the discrimination measure. Despite these limitations, the study points to potential links between lifetime discrimination and depressive symptoms in pregnancy.

The Siljan ring structure (368 +/- 1.1 Ma) is the largest known impact structure in Europe. It isa 65-km-wide, eroded, complex impact structure, displaying several structural units, including a central uplifted region surrounded by a ring-shaped depression. Associated with the impact crater are traces of a post-impact hydrothermal system indicated by precipitated and altered hydrothermal mineral assemblages. Precipitated hydrothermal minerals include quartz veins and breccia fillings associated with granitic rocks at the outer margin of the central uplift, and calcite, fluorite, galena, and sphalerite veins associated with Paleozoic carbonate rocks located outside the central uplift. Two-phase water/gas and oil/gas inclusions in calcite and fluorite display homogenization temperatures between 75 degrees C and 137 degrees C. With an estimated erosional unloading of approximately 1 km, the formation temperatures were probably not more than 10-15 degrees C higher. Fluid inclusion ice-melting temperatures indicate a very low salt content, reducing the probability that the mineralization was precipitated during the Caledonian Orogeny. Our findings suggest that large impacts induce low-temperature hydrothermal systems that may be habitats for thermophilic organisms. Large impact structures on Mars may therefore be suitable targets in the search for fossil thermophilic organisms.

This investigation focuses on the relationship between racial discrimination and health. Many studies have shown a link between race and differential health outcomes, but few have actually measured racial discrimination. Such studies leave unanswered the question of exactly how the experience of racial discrimination might affect health. Racial discrimination is argued to act in the same fashion as other chronic stressors by increasing blood pressure. However, racial discrimination may also give rise to the sense of thwarted aspirations, itself a stressor, and make the active coping style of "John Henryism" more likely. In these data, we measure perceived racial discrimination for a sample of African Americans and find that experiencing racially-based discriminatory treatment does not impact health. There is no relationship between doctor-diagnosed hypertension and cardiovascular disease, and being the victim of racially biased treatment. We discuss possible reasons for this, and argue that greater conceptualization about the postulated link between discrimination and health is necessary, as well as explicitly designed studies for the purpose of examining this postulated relationship.

The research on external (social system) and internal (personal) attributions to mental health outcomes for African Americans is reviewed. Although many blacks have aspirations that they are unable to achieve, the motivational and mental health consequences of this situation are unclear. Several researchers have suggested that it is adaptive for African Americans to reduce striving effort and bring personal goals more in line with the objective realities of an unfair opportunity structure. Others have proposed that because an unjust system is to blame, the most appropriate response is to work collectively with other group members to make the system more open to opportunities for advancement. Epidemiologic research on the relationship of internal-external locus of control to mental disorder has generally found that being internal has positive mental health effects; while having an external orientation is detrimental. This paper addresses these issues by demonstrating that the psychiatric-epidemiologic and the race-consciousness literatures lead to opposite predictions about the relationship of external attributions (fatalism and system blame) to mental health. The article concludes with a series of issues that need to be addressed in order to advance knowledge about social and psychological risk factors for psychiatric disorders in African Americans.

A three-wave panel study of auto plant closings focused on the mental health effects of unemployment on blue-collar workers. This paper explores how the impact of long-term unemployment varies across race and gender. We also examine whether other demographic factors can themselves modify the impacts of race and gender. Dependent variables include two measures of distress and two drinking measures. Results showed that the effect of long-term unemployment on distress and drinking was more severe among less educated workers, and responses of blacks were especially sensitive to level of education. In addition, men showed a greater association of long-term unemployment with depression (and to some extent anxiety) than did women. Marriage affected the responses of men but not of women, and of whites but not of blacks. Explanatory variables--the worker's experiences of financial hardship, other negative life events, and lack of a confidant--largely accounted for male-female differences. We conclude by discussing theoretical implications of these effects and address the limitations of the traditional term "vulnerability" in describing them.

Despite the many important benefits of leisure-time physical exercise on health, many Americans do not engage in exercise. This is more the case for the African-American population. This study assesses the impact of efficacy cognitions on leisure-time physical activity (LTPA) in an African-American sample. Our findings show that LTPA is predicted by the sense of efficacy in this African-American sample. Further analyses address significant factors in the prediction of the sense of efficacy. We find that the general sense of mastery predicts efficacy in this African-American sample. This may be especially significant for the African-American population. Also, analysis reveals surprising findings concerning characteristics predictive of efficacy cognitions. The highly educated are least likely to believe in the efficacy of preventive health behavior.

Collecting three waves of panel data offered an unusual opportunity to examine the long-term outcomes of the use of mental health services. Data are drawn from a panel study of autoworkers. Waves 1, 2, and 3 consisted of 1,597, 1,288, and 1,136 workers, respectively, from four closing and 12 non-closing plants in Southeastern Michigan. Our results revealed a surprising finding: use of mental health services, whether in the general or specialty sectors, had a negative impact on the subsequent mental health of autoworkers in our sample. The use of mental health services is associated with increased levels of psychological distress. Further, we show that the negative association between use of mental health services and distress was greater for certain demographic groups, notably Blacks, men, older workers, the poorly educated, and the unemployed, depending upon the type of service used. Finally, we sought to uncover the reasons for the negative impact of services use. Results suggest that self-blame, for one, contributed to the negative impact of using mental health services.

The relationship of social ties to health behavior is studied in this paper. The general hypothesis tested is that those with social relationships are more likely to avoid health damaging behavior. Patterns regarding specific social ties and particular health behaviors are examined. Findings indicate the relationships of spouse, organization member, and friend are related to preventive health behavior; spouses are less likely smokers, drinkers, and heavy drinkers. The friend relationship is related to decreased smoking behavior, while the employee relationship is related to increased drinking. A consistent predictor of health behaviors is the social tie of organization member. People with relationships as organization members are more likely always to wear seat belts, smoke and drink less, and consume lower amounts of these substances.

This study of coping with unemployment traces the distress levels of workers in 4 closing and 12 nonclosing General Motors (GM) plants. Workers were interviewed 3 months before plants closed, 1 year after, and 2 years after (final N = 1,136). Tested were (a) effects of unemployment on symptoms of depression, anxiety, and somatization; (b) linkages between depression and subsequent unemployment, controlling for workers' gender, race, marital status, age, education, prior income, and seniority; and (c) the relationship between workers' coping decisions and subsequent depression. Results showed that unemployment at Waves 2 and 3 was related to prior frequency of symptoms of depression. Depression, in turn, was alleviated for workers whose coping decisions at Wave 2 fit with their Wave 3 outcomes: those who both wanted and found a job, lost a job they disliked, or remained unemployed as planned.

Large-scale 1987 General Motors plant shutdowns offered an unusual opportunity to study effects of actual and anticipated unemployment on mental health. Workers from four closing and 12 nonclosing plants (Ns = 831 and 766 respectively) were interviewed approximately three months before scheduled plant closings. Dependent variables were baseline frequencies of somatic, depressive, and anxiety symptoms. The quasi-experimental design made it possible to explore systematically the mental health problems of individual autoworkers as a function of their employment status, their demographic characteristics, and the interaction of the two. Three groups were formed by dividing workers at closing plants into those already laid off and those anticipating layoff; the third group consisted of workers in nonclosing plants. Results revealed a pattern of interaction between unemployment and demographic variables, showing differential vulnerability to job loss. Less educated blacks were especially affected; follow-up analyses showed that their more distressed mental health could not be attributed entirely to other, prior stressors.

This paper considers the role of social mobility to hypertension among blacks. Using a nationally representative sample of the adult black population, this research finds no effects of intergenerational socioeconomic mobility. Minimal effects are found for geographic mobility; geographic moves bears a small positive relationship to hypertension. The implications for a theory of mobility effects on black health are discussed.

This study examines the relationship between anger expression and life stress in a nationally representative sample of black adults. Recent research of mostly white subjects has shown that anger-hostility, one of the components of the Type A behavioral pattern, is an important predictor of health problems. The findings of the present inquiry indicate that anger-hostility is an important predictor of life stress, and that people with higher levels of anger conflict are more likely to experience negative life events. Moreover, negative life events and anger are shown to be independent predictors of health problems among blacks. The implications of these results for future studies of the health of black Americans are discussed.

Using data from two national surveys, findings from this research indicated that blacks were more likely than whites to seek help from mental health professionals, particularly for economic and physical health problems. Blacks also sought help more often than whites from other sources of professional help, such as teachers, lawyers, social workers and emergency rooms. On the other hand, whites were more likely to seek help from medical sources for all types of problems, and from clergy members.

This study examined the relationship between anger expression, other psychosocial measures, and health problems in a nationally representative, cross-sectional sample of 1277 black adults. Subjects indicating a high level of outwardly expressed anger during a period in which they experienced a severe personal problem had a significantly higher number of health problems than their counterparts who expressed low and moderate levels of anger. Anger expression also significantly interacted with a measure of life strain (employment status) to predict health problems. Blacks who were unemployed were more likely to have a higher number of health problems if anger was expressed outwardly at a high level. The relationship was found to be independent of age, gender, urbanicity, smoking, and drinking problems. The overall pattern of the findings suggests that blacks who are at increased risk for health problems may be identified by how often anger is experienced and expressed during periods of emotional distress.