A socioeconomic assessment of human exposure to ozone in the South Coast Air Basin of California

The purpose of this study is to assess by age, race, ethnicity, and income the effects of air pollution control measures and population growth on human exposure to ozone in the South Coast Air Basin of California (SoCAB). A methodology to study human exposure to air pollutants from a socioeconomic perspective has been developed. Specifically, the Regional Human Exposure model (REHEX-II) has been applied to estimate historical (1980-1982) and recent (1990-1992) human exposure to ozone. The model accounts for time spent in different microenvironments for different age groups and incorporates long-term air quality data with high spatial resolution. The simulation results, expressed as per capita hours of exposure to ozone above various concentration thresholds, are associated with population race, ethnicity, and per capita income. The results indicate that ozone exposure differences by race and ethnicity have diminished over time. However, the study suggests that on average, low income areas may be experiencing higher ozone exposure than high income areas, suggesting that environmental health risks (e.g., respiratory diseases) may be systematically higher for low income groups in the SoCAB.     

Ascaris lumbricoides intensity in relation to environmental, socioeconomic, and behavioral determinants of exposure to infection in children from southeast Madagascar

Ascaris lumbricoides worm counts were examined as the outcome products of exposure proxy variables. A survey of 663 children, 4-10 yr old, living in southeastern Madagascar revealed prevalences of 93% for A. lumbricoides, 55% for Trichuris trichiura, and 27% for hookworm. Worm expulsions were conducted on 428 of these children; the data revealed an overdispersed distribution of A. lumbricoides, with an arithmetic mean of 19.2 worms per child. A concurrent socioeconomic household survey was conducted by visitation and interview. Exposure to infection was assessed by environmental, demographic, behavioral, and socioeconomic indicators. Ascaris lumbricoides aggregations were associated with gender, housing style, ethnicity, and agricultural factors. The results suggest that exposure and infection are ubiquitous in this child population, and that A. lumbricoides intensity is influenced by gender-related behavioral and environmental factors that contribute to exposure.     

Epidemiological investigations on arbovirus infections at Igbo-Ora, Nigeria

Using mortality and incidence data from Alameda County, California, this study attempted to determine whether the higher occurrence rate of prostatic cancer among black men as compared with whites in the United States might be explained by racial differences in factors associated with socioeconomic status. Each death or case of prostatic cancer was assigned to a social class based on census tract of residence, and rates by race and socioeconomic status were computed. Comparison of age-specific mortality and incidence rates by socioeconomic status reveals no gradient in either whites or blacks. The higher risk for blacks holds up at almost every age and socioeconomic level. However, the racial differences are less pronounced for incidence than for mortality. Racial differences in the occurrrence of deaths appearing in Part II of the death certificate are also examined.     

A Study of the Relationship between Air Pollutants and Inversion in the ABL over the City of Lanzhou

By analyzing the pollutant concentrations over the urban area and over the rural area of the city of Lanzhou,Gansu Province,China,the relationships between the daytime inversion intensity and the pollutant concentration in the atmospheric boundary layer (ABL) are studied with the consideration of wind speed and direction,potential temperature,specific humidity profiles,pollutant concentration in the ABL,the surface temperature,and global radiation on the ground.It was shown that the daytime inversion is a key factor in controlling air pollution concentration.A clear and positive feedback process between the daytime inversion intensity and the air pollutants over the city was found through the analysis of influences of climatic and environmental factors.The mechanisms by which the terrain and air pollutants affect the formation of the daytime inversion are discussed.The solar radiation as the essential energy source to maintain the inversion is analyzed,as are various out-forcing factors affecting the inversion and air pollutants.At last,a physical frame of relationships of air pollution with daytime inversion and the local and out-forcing factors over Lanzhou is built.     

Why study socioeconomic factors and cancer?

The occurrence of cancer within a population can be studied at many different levels, including forms of social organization, the individual, a particular organ system, or a particular molecule. The causes of cancer can also be studied at these different levels, including socioeconomic factors, lifestyle, the organ burden of a carcinogen, or DNA adducts. Clearly, there are advantages in understanding disease causation at all of the different levels at which it operates. Although cancer risk factors such as tobacco smoke may appear to operate at the individual level, exposure may occur due to a wide range of political, economic and social factors; conversely, tobacco smoke ultimately also has effects at the cellular and molecular levels, including the production of mutations in DNA. Of course, it is important to gain information, and take action, at all possible levels, but the history of public health shows that changes at the population level are usually more fundamental and effective than changes at the individual level, even when a single risk factor accounts for most cases of disease. In this sense, a risk factor such as smoking can be regarded as a secondary symptom of deeper underlying features of the social and economic structure of society. Thus, just as a variety of health effects in various organ systems (for example, various types of cancer) may have a common contributing cause (for example, tobacco smoking) at the level of the individual, a variety of individual exposures (for example, smoking and diet) may have common socioeconomic causes at the population level. In many instances there is clear evidence that cancer is related to socioeconomic factors, but this does not appear to be fully explained by known risk factors. More importantly, there is little evidence as to which socioeconomic factors are of most importance, or whether it is the overall 'package' of social inequality that is responsible for the differences in cancer risk. The aim of this book is therefore to summarize what is already known, and to identify gaps in our knowledge.     

Exposure to occupational carcinogens and social class differences in cancer occurrence

It has been estimated that occupational exposures are responsible for about 4% of all human cancers in industrialized countries. These cancers are concentrated among manual workers and in the lower social classes, thus contributing to the social class gradient in cancer incidence and mortality. On the basis of the 1971 cancer mortality data from England and Wales, it was estimated that occupational cancer is responsible for about a third of the total cancer difference between high (I, II and III-NM) and low (III-M, IV and V) social classes, and for about half of the difference for lung and bladder cancer. However, direct evidence on the extent of the contribution of occupational exposure to carcinogens to social class differences is lacking, and several problems, such as the possible interaction between carcinogens and the effect of extraoccupational confounding factors, add further elements of uncertainty.     

Treatment of orbicularis oculi muscle hypertrophy in lower lid blepharoplasty

Curschmann's spirals have been observed for more than 100 yr in the sputum of patients affected by lung cancer, asthma, chronic bronchitis, or in asymptomatic smokers. However, to date, their clinical significance and pathogenesis have not been completely explained. Curschmann's spirals in the sputum of two populations were studied: 164 traffic policemen of Rome and 119 subjects living in a rural district near Perugia. Of these two groups, only the first were exposed daily to urban environmental pollutions. Spirals were detected in the sputum of 29 traffic policemen and in 3 subjects from the group not exposed daily to urban environmental pollutants. Between these two groups of subjects the difference was statistically significant (P < 0.001). Therefore, daily exposure to urban atmospheric pollution may play a role in the production of Curschmann's spirals. Our two groups were also divided into smokers and nonsmokers to evaluate if cigarette smoking could influence the presence of spirals in sputum. Our study confirms the association of spirals in the sputum of smokers but also indicates their presence in individuals who never smoked but were exposed to environmental pollutants. We also noticed that exposure to pollution and cigarette smoking may have a synergistic effect on the formation of spirals in the respiratory tract.     

Adverse effects of sunlight on the skin

Many people consider a summer's day pleasant: warm and bright. The sun's ultraviolet rays do not contribute to the pleasure, and are biologically mainly harmful. As UV radiation does not penetrate any deeper than our skin, this organ has to be particularly well adapted to the UV exposure. The skin exploits the UV radiation for the synthesis of vitamin D3. Our day-to-day exposure suffices for this beneficial UV effect. Excessive exposure, as in sunbathing, only contributes to the adverse effects, like sunburn and suppression of cellular immunity in the short term, and 'photoaging' and skin cancer in the long term. The UVB radiation in sunlight is mainly responsible for these harmful effects, the UVA radiation to a far lesser extent (10-20% contribution). The UVA radiation from modern tanning equipment does not differ from that in sunlight, but UVA radiation does not lead to vitamin D3 production; it rather degrades vitamin D3 and a tan offers insufficient protection against the UVB radiation in full sunlight.     

Tumorigenic conversion of a non-tumorigenic rat urothelial cell line by overexpression of H2O2-generating peroxisomal fatty acyl-CoA oxidase

Two of the major cutaneous consequences of ultraviolet (UV) radiation exposure are immunosuppression and the development of skin cancer. This study examined whether these effects are genetically determined. Suppression of contact hypersensitivity by local, low-dose UV radiation was examined in what have been termed "UV-susceptible" and "UV-resistant" strains of mice. C3H/HeJ mice ("UV resistant") were resistant to the adverse effects of low-dose UV radiation when normal doses of hapten were applied to UV-irradiated skin; however, they were sensitive when the amount of hapten used for sensitization was reduced. A similar effect was observed in BALB/c mice ("UV resistant") and when the hapten was dimethylbenz(a)anthracene, thus indicating that the genetic variation was not strain or hapten specific. Despite the fact that some strains were sensitive and some were resistant to low-dose UV radiation when high doses of hapten were employed, all strains initially sensitized to hapten through UV-irradiated skin were found to be unresponsive when rechallenged on normal skin, no matter what the initial sensitizing dose of hapten was. To determine whether other biologic effects of UV also exhibited genetic variation, C3H/HeN and C3H/HeJ mice were compared for susceptibility to UVB-induced skin cancer formation. C3H/HeJ mice developed significantly more tumors than C3H/HeN mice when subjected to a single dose of UV radiation followed by repeated exposure to the tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate. These studies provide strong evidence that genetic factors influence individual susceptibility to the biologic effects of UV radiation.     

Environmental tobacco smoke and lung cancer

In a case-control study of 1,004 lung cancer cases and 1,004 population controls, all nonsmokers (71 cases, 236 controls) were interviewed for their exposure to environmental tobacco smoke. On the basis of indices of duration, we separated intermediate and high exposures from low or no exposure. The odds ratio for high exposure was 2.09 (95% confidence interval = 1.02-4.28). Exposure from the spouse was only weakly associated with lung cancer risk. We found little association for exposure during childhood. High exposure at the work place showed an odds ratio of 1.91. There was little indication of confounding by dietary habits.     

Environmental causes for sinonasal cancers in pet dogs, and their usefulness as sentinels of indoor cancer risk

A case-control study was conducted to investigate the environmental causes of sinonasal cancers among pet dogs. Sinonasal cancer (SNC) cases and digestive cancer controls from the years 1989 through 1993 were obtained from a veterinary histopathology database. Owners were mailed a self-administered survey requesting information on canine factors, owner demographics, household exposures (including environmental tobacco smoke), and local pollution. A total of 129 case owners and 176 control owners returned completed surveys: a response rate of approximately 72%. Only household exposures were associated with increased SNC risk. Use of indoor coal or kerosene heaters represented the strongest risk factors, with significant adjusted odds ratios of 4.2 and 2.2 respectively. Environmental tobacco smoke exposure was not a risk factor and was suggestive of a nonsignificant, mildly protective effect at the lower exposure levels. Increasing nasal length was a significant risk factor, and there was effect modification between nasal length and coal or kerosene combustion. No self-reported measures of local pollution, such as urban status or residence within 1 mile of a factory, were associated with SNC risk. These results suggest that canine SNC has a strong environmental component and highlight the importance of indoor exposures, especially from fossil fuel combustion products. These results also suggest that pet dogs represent excellent sentinels for indoor cancer risk and that canine SNC cases can be used as early markers of household exposure to carcinogenic combustion products.     

Effect of environmental pollutants on the C-reactive protein of a freshwater major carp, Catla catla

C-reactive proteins (CRP) have been affinity purified to electrophoretic homogeneity from the sera of major carp, Catla catla before and after exposure to environmental pollutants. Exposure to these pollutants elevate the levels of circulating CRPs to 2.8-3.5 times the normal values. Kinetic studies of metal intoxication indicate that a unique molecular variant of CRP is present in the serum at the peak level of acute phase induction, and this variant coexists with normal CRPs. Carbohydrate analysis and lectin binding reveals that these CRPs are glycoproteins differing significantly in total carbohydrate contents. Their electrophoretic mobilities in native gel are different but become identical on desialylation and deglycosylation implying that the molecular variants vary in the glycan parts. All these forms of CRP contain two nonidentical subunits of Mr 22 and 29 kDa. Examination of their immunological crossreactivity demonstrate their similarity in overall molecular topology but their differences in the quantitative extent of binding are reflected.     

Risk factors for incident and recurrent condylomata acuminata among men. A population-based study

BACKGROUND AND OBJECTIVES: The rapid increase in the number of physician office visits for condylomata acuminata and the association of human papillomavirus and cancer has prompted renewed interest in the epidemiology of this sexually-transmitted disease. Few epidemiologic studies have examined what risk factors are associated with condylomata acuminata in men. GOAL: To determine what factors may predispose a man to the occurrence of condylomata acuminata. STUDY DESIGN: A population-based case-control study was conducted among male members of a health maintenance organization. Patients were men 18 years or older who were seen for condyloma at one of four primary care clinics of Group Health Cooperative of Puget Sound between April 1, 1987 and September 30, 1991. Control subjects were frequency matched to the patients on clinic site, race, and age. In-person interviews were used to ascertain exposure histories from both patients and control subjects. RESULTS: Recurrent condyloma was reported by about one third of our patients. Patients with multiple partners were strongly associated with developing the disease. Several factors were either more strongly or only associated with recurrent disease. Other behavioral measures, such as recreational drug use, were also related the occurrence of condyloma. CONCLUSION: These results confirm the sexual-transmitted mechanism of condyloma in men. Exposure to multiple partners was associated with elevated risk of both recurrent and incident disease. Other cofactors may be involved in the etiology of condyloma.     

Socioeconomic status and cancer screening

The only widely applied cancer screening programmes are those for cancers of the cervix and female breast. Participation in breast cancer screening has been shown to depend on income and education, health insurance and type of health service. Women in low social classes tend to have lower screening participation rates than those in higher classes. Socioeconomic differences in screening practices tend to decrease when participation is promoted, cultural and economic barriers are removed, and social support is offered. In both developed and developing countries, women of low socioeconomic status have a higher than average risk of cervical cancer, and a lower than average participation in Pap smear screening.     

Tobacco smoking, cancer and social class

Consumption of tobacco products, both by smoking and by other means, has long been causally connected with cancers of the lung, larynx, mouth and pharynx, oesophagus, bladder, and many other sites. Tobacco is the main specific contributor to total mortality in many developed countries and has become a major contributor in the developing countries as well. In most industrialized countries, prevalence of cigarette smoking is currently higher in low than in high social classes, although in some industrialized countries smoking was more frequent in high social classes during the first half of this century. The latter pattern of tobacco consumption is more likely to apply to developing countries. To formulate and carry out effective tobacco control activities it is essential to assess the relative incidence of tobacco-related cancers in different social strata and the prevalence of tobacco use across strata. Despite many years of data gathering the information base is far from complete, especially in developing countries where tobacco use is increasing rapidly, and where aggressive marketing by the transnational tobacco industry is occurring. A critical question is the extent to which tobacco usage can 'explain' the observed social class differences in cancer risk. Class differences in lung cancer are likely to be mostly related to the unequal distribution of tobacco smoking between social classes, and in some fairly simple situations this has been satisfactorily demonstrated. Nevertheless, there are many unresolved issues, especially with regard to the role of collateral exposures, such as hazardous occupations, poor diet, and limited access to health care. The question of whether tobacco use 'explains' socioeconomic differences in one or more of the cancers that it causes has rarely been directly addressed in epidemiological studies.     

Lifetime exposure to environmental tobacco smoke among urban women: differences by socioeconomic class

This study sought to determine cumulative lifetime exposure to environmental tobacco smoke (ETS) among urban women in relation to sociodemographic factors. In a population survey carried out in Geneva, Switzerland, during 1993-1995, a representative sample of 1,883 women aged 35-74 years answered interview questions on lifetime ETS exposure. Exposed women were defined as those who had spent at least 1 hour daily in a smoky environment during 1 or more years. The prevalence of current ETS exposure was 31.0% among 1,458 never or former smokers. Lifetime prevalence was 58.3% among 1,061 never smokers. The home (42.1%) and the workplace (39.6% of employed women) were the most frequent sources of ETS exposure, leisure time activity being a secondary source. Throughout a lifetime, work accounted for the greatest average intensity of exposure (on average, 19 hours of exposure per week), while the longest duration of exposure (on average, 18 years) was in the home. Cumulative lifetime exposure (intensity (in hours/week) x duration) from all sources combined was 308 hours/week-years, which can correspond to 30.8 hours/week over a period of 10 years or 20.5 hours/week over a period of 15 years. Women from low socioeconomic classes had more intense and longer exposures than women from higher socioeconomic classes, mainly because of work exposure. Both the intensity and the duration of lifetime ETS exposure were greater than previously suspected. Reduction of ETS exposure in the workplace should be a public health priority.     

Possible explanations for social class differences in cancer patient survival

Social class differences in cancer patient survival have been reported for most cancer types and for a number of countries. The etiology of these differences has been studied less thoroughly and less systematically than social class differences in cancer occurrence. Stage of disease at diagnosis appears to be the most important factor contributing to the social class differences in cancer patient survival. This has been observed most clearly for gastrointestinal and gynaecological cancers. Social class differences in survival are generally wider for patients diagnosed with cancer at local stages than for those diagnosed with cancer at advanced stages. The reasons why cancers are more frequently diagnosed at a local stage in high than in low social classes in not properly understood at the moment. Of other potential contributing factors, the role of treatment and psychosocial factors has scarcely been studied. Biological indicators of tumour aggressiveness have failed to explain the social class differences.     

Effects of air pollution on health

Air pollution is composed of a particulate phase and a gaseous phase. The particulate phase, consisting of dust and aerosols, is the vehicle of toxic pollutants, transporting them into the respiratory tract. The irritants (sulphur dioxide, nitrogen oxides, aldehydes, and hydrocarbons) are the most important pollutants as regards health; the mucous membranes of the eyes and the respiratory tract are mostly affected. Other substances penetrate into the organism where they can develop actions harmful to various organs (carbon monoxide), generate cancer (polyaromatic hydrocarbons) or attack enzymatic systems (lead). Epidemiologic studies have revealed that populations exposed to high degrees of air pollution show increased mortality, which is mainly due to illnesses of the respiratory tract. Atmospheric pollution can also cause sensations of unpleasantness due to irritations of the eyes and the respiratory tract, bad odours, and the impairment of visibility and sunlight.     

Hypochondriasis in the elderly: a reaction to social stress

Hypochondriasis in the elderly is often a preventable or reversible syndrome. It can become chronic if the patient finds no relief from social stress or becomes dependent upon medical services as a source of support. When this is recognized, psychotherapeutic intervention is necessary. Although no socioeconomic group is exempt, hypochondriasis in the elderly occurs more often among the lower social classes. Its higher prevalence in this group is attributable to the frequency and severity of social stress and the loss of alternative social opportunities. If psychotherapeutic intervention is necessary, the elderly hypochondriac patient should be helped to recognize social stress as a major source of the problem and to develop a realistic method of coping with it. Apparently the precipitating factors are often in the socioeconomic sphere; hence, social planners should be aware of this fact if the demands on the health care system are to be reduced.     

Laying the Foundation for Quantifying Regional Exposure to Social Phenomena: Considering the Case of Legalized Gambling as a Public Health Toxin.

Exposure and adaptation models provide competing perspectives of the environmental influence on the development of addictive disorders. Exposure theory suggests that the presence of environmental toxins (e.g., casinos) increases the likelihood of related disease (e.g., gambling-related disorders). Adaptation theory proposes that new environmental toxins initially increase adverse reactions; subsequently, symptoms diminish as individuals adapt to such toxins and acquire resistance. The authors describe a new public health regional exposure model (REM) that provides a tool to gather empirical evidence in support of either model. This article demonstrates how the strategic REM, modified to examine gambling exposure, uses standardized indices of exposure to social phenomena at the regional level to quantify social constructs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)