1,3-Butadiene has been assessed as a Priority Substance under the Canadian Environmental Protection Act. The general population in Canada is exposed to 1,3-butadiene primarily through ambient air. Inhaled 1,3-butadiene is carcinogenic in both mice and rats, inducing tumors at multiple sites at all concentrations tested in all identified studies. In addition, 1,3-butadiene is genotoxic in both somatic and germ cells of rodents. It also induces adverse effects in the reproductive organs of female mice at relatively low concentrations. The greater sensitivity in mice than in rats to induction of these effects by 1,3-butadiene is likely related to species differences in metabolism to active epoxide metabolites. Exposure to 1,3-butadiene in the occupational environment has been associated with the induction of leukemia; there is also some limited evidence that 1,3-butadiene is genotoxic in exposed workers. Therefore, in view of the weight of evidence of available epidemiological and toxicological data, 1,3-butadiene is considered highly likely to be carcinogenic, and likely to be genotoxic, in humans. Estimates of the potency of butadiene to induce cancer have been derived on the basis of both epidemiological investigation and bioassays in mice and rats. Potencies to induce ovarian effects have been estimated on the basis of studies in mice. Uncertainties have been delineated, and, while there are clear species differences in metabolism, estimates of potency to induce effects are considered justifiably conservative in view of the likely variability in metabolism across the population related to genetic polymorphism for enzymes for the critical metabolic pathway.
Europe was officially declared free from malaria in 1975; nevertheless, this disease remains a potential problem related to the presence of former vectors, belonging to the Anopheles maculipennis complex. Autochthonous-introduced malaria cases, recently reported in European countries, together with the predicted climatic and environmental changes, have increased the concern of health authorities over the possible resurgence of this disease in the Mediterranean Basin. In Italy, to study the distribution and bionomics of indigenous anopheline populations and to assess environmental parameters that could influence their dynamics, an entomological study was carried out in 2005-2006 in an at-risk study area. This model area is represented by the geographical region named the Maremma, a Tyrrhenian costal plain in Central Italy, where malaria was hyperendemic up to the 1950s. Fortnightly, entomological surveys (April-October) were carried out in four selected sites with different ecological features. Morphological and molecular characterization, blood meal identification, and parity rate assessment of the anophelines were performed. In total, 8274 mosquitoes were collected, 7691 of which were anophelines. Six Anopheles species were recorded, the most abundant of which were Anopheles labranchiae and An. maculipennis s.s. An. labranchiae is predominant in the coastal plain, where it is present in scattered foci. However, this species exhibits a wider than expected range: in fact it has been recorded, for the first time, inland where An. maculipennis s.s. is the most abundant species. Both species fed on a wide range of animal hosts, also showing a marked aggressiveness on humans, when available. Our findings demonstrated the high receptivity of the Maremma area, where the former malaria vector, An. labranchiae, occurs at different densities related to the kind of environment, climatic parameters, and anthropic activities.
IMPORTANCE UV radiation (UVR) exposure is the primary environmental risk factor for developing cutaneous malignant melanoma (CMM). OBJECTIVE To measure changes in sun behavior from the first until the third summer after the diagnosis of CMM using matched controls as a reference. DESIGN, SETTING, AND PARTICIPANTS Three-year follow-up, observational, case-control study performed from May 7 to September 22, 2009, April 17 to September 15, 2010, and May 6 to July 31, 2011, at a university hospital in Denmark of 21 patients with CMM and 21 controls matched to patients by sex, age, occupation, and constitutive skin type participated in the study. Exposure to UVR was assessed the first and second summers (n=20) and the first and third summers (n=22) after diagnosis. Data from 40 participants were analyzed. MAIN OUTCOMES AND MEASURES Exposure to UVR was assessed by personal electronic UVR dosimeters that measured time-related UVR in standard erythema dose (SED) and corresponding sun diaries (mean, 74 days per participant each participation year). RESULTS Patients' daily UVR dose and UVR dose in connection with various behaviors increased during follow-up (quantified as an increase in daily UVR dose each year; all days: mean, 0.3 SED; 95% CI, 0.05-0.5 SED; days with body exposure: mean, 0.6 SED; 95% CI, 0.07-1.2 SED; holidays: mean, 1.2 SED; 95% CI, 0.3-2.1 SED; days abroad: 1.9 SED; 95% CI, 0.4-3.4 SED; and holidays with body exposure: mean, 2.3 SED; 95% CI, 1.1-3.4 SED). After the second year of follow-up, patients' UVR dose was higher than that of controls, who maintained a stable UVR dose. No difference was found between groups in the number of days with body exposure or the number of days using sunscreen in the second and third years of follow-up. CONCLUSIONS AND RELEVANCE Our findings suggest that patients with CMM do not maintain a cautious sun behavior in connection with an increase in UVR exposure, especially on days with body exposure, when abroad, and on holidays.
A 10-year follow-up of a population-based study of people with multiple sclerosis in Stockholm, Sweden: changes in health-related quality of life and the value of different factors in predicting health-related quality of life.
Health-related quality of life (HRQL) in people with multiple sclerosis (PwMS) is negatively affected compared to that of the general population. Cognitive impairment and depressive symptoms have been shown to predict worse HRQL in a short-term perspective. Considering the progressive nature of MS, it is essential to include the long-term (10 years) perspective of HRQL in PwMS.
The aim of this 10-year follow-up of a population-based sample of PwMS was to explore changes in and the predictive value of personal factors, degree of MS disability, depressive symptoms and cognitive impairment on HRQL.
Data on personal and disease-specific factors, mood, and cognitive function was collected. Data on HRQL was collected, seen as a health profile with the Sickness Impact Profile, as a health index with the EuroQol 5D and as a single global question with the EQ Visual Analog Scale.
HRQL worsened over 10 years according to the health profile (Sickness Impact Profile Total and its physical dimension) and according to the health index. The effect sizes were small. HRQL assessed with the single global question remained unchanged. Depressive symptoms and cognitive impairment predicted worse HRQL.
In a 10-year perspective the HRQL with regard to its physical domain or when seen as a total health profile tends to get worse in PwMS. Yet, HRQL with regard to its psychosocial domain and with regard to PwMS' self-rated health, remains stable. There is a potential for health-care professionals to decrease the impact of modifiable factors on HRQL in PwMS by identifying those with depressive symptoms and/or cognitive impairment and initiating evidence-based treatment as well as meeting the need for environmental facilitators aiming at reducing disability.
In order to investigate how well-being and ill health is affected by the process of aging, the main aim was to investigate these self-perceived aspects of health over a 10-year period among older Swedish adults. The aim was also to study how these aspects correlated with objectively assessed functional limitations, use of mobility device, person-environment (P-E) fit (also denoted accessibility), problems in housing, and activity of daily living (ADL) dependence. Using the Swedish national population register, a baseline sample of persons aged 75-84 years was identified. Out of the 133 participants at baseline (1994), the 31 participants still available 10 years later were included. The data were collected by means of interview and observation at home visits. Overall, the participants rated their subjective well-being as high and a stable prevalence of ill-health symptoms over time was reported. Changes in subjective well-being as related to changes in functional aspects seem to mainly occur earlier in the aging process, while as time goes by these relations weaken. ADL dependence, however, is more influential in more advanced age. The results confirm the complexity of the construct of health. A main contribution is that the results shed light on the importance of taking the impact of environmental factors into consideration.
The study aimed to explore changes in the prevalence of psychological distress and co-occurring psychological symptoms among 19-34 years old Finnish university students between the years 2000 and 2012.
The prevalence of perceived frequent psychological symptoms was compared in four nationwide cross-sectional student health surveys with random samples (N=11,502) in the following years: 2000 (N=3,174), 2004 (N=3,153), 2008 (N=2,750), and 2012 (N=2,425).
In the time phase from 2000 to 2012, the overall psychological distress (12-item General Health Questionnaire, GHQ-12) increased from 22% to 28%, while there was also an increase in the frequently experienced psychological symptoms (depressiveness from 13% to 15%, anxiety from 8% to 13%, concentration problems from 12% to 18%, and psychological tension from 13% to 18% with a peak prevalence observed in 2008). The co-occurrence of different psychological symptoms increased as well. Psychological distress was more common in females and in older students.
The findings suggest an increasing trend of frequent psychological distress among Finnish university students over the years from 2000 to 2012, with the peak prevalence occurring in 2008, which may reflect the growing multifaceted environmental demands.
Since Dr. Fogh-Andersen's legendary 1942 thesis, the Danish facial cleft population has been one of the most extensively studied in terms of epidemiology and genetic-epidemiology. The etiology of cleft lip and/or palate (CLP) is still largely an enigma, and different results concerning environmental and genetic risk factors are obtained in different countries and regions. This may be due to etiological heterogeneity between settings. Therefore, an in-depth studied area with an ethnically homogeneous population, such as Denmark, has provided one of the best opportunities for progress in CLP etiological research. The present review summarizes epidemiological and genetic-epidemiological studies conducted in the 20th century Danish facial cleft population. Furthermore, analyses of sex differences, time trends and seasonality for more than 7000 CLP cases born in Denmark in the period 1936 to 1987 are presented. The review also points toward the excellent opportunities for continued etiological CLP research in Denmark in the 21st century using already established resources and an on-going prospective cohort study of 100,000 pregnant women.
The level of radiation exposure in children in Belarus caused by the Chernobyl accident was investigated on the basis of whole body 137Cs count. The subjects were 10,062 children (4,762 boys and 5,300 girls) in Mogilev and Gomel, Belarus, who received Chernobyl Sasakawa Health and Medical Cooperation Project health examinations from May 1991 to December 1992 and who were 5-16 y old at the time of examination. The median whole body 137Cs count per body weight varied from 21-48 Bq kg-1 and from 28-126 Bq kg-1 in Mogilev oblast and Gomel oblast, respectively. (The "oblast" is the largest administrative district constituting the country. Belarus consists of 6 oblasts). Corresponding annual effective dose equivalents were all less than the public dose limit of 1 mSv y-1, but the observed levels in the children were considerably higher than the average level of 2.3 Bq kg-1 reported in the past for the former Soviet Union.
Comment In: Health Phys. 1995 May;68(5):733-57730075
Division of Intramural Research, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709, USA.
Epigenetic modifications, such as DNA methylation, due to in utero exposures may play a critical role in early programming for childhood and adult illness. Maternal smoking is a major risk factor for multiple adverse health outcomes in children, but the underlying mechanisms are unclear.
We investigated epigenome-wide methylation in cord blood of newborns in relation to maternal smoking during pregnancy.
We examined maternal plasma cotinine (an objective biomarker of smoking) measured during pregnancy in relation to DNA methylation at 473,844 CpG sites (CpGs) in 1,062 newborn cord blood samples from the Norwegian Mother and Child Cohort Study (MoBa) using the Infinium HumanMethylation450 BeadChip (450K).
We found differential DNA methylation at epigenome-wide statistical significance (p-value
This paper provides a short overview of cobalt-related diseases with particular reference to the potential carcinogenicity of cobalt compounds, and a review of a 10-year surveillance programme on plate painters exposed to cobalt in two Danish porcelain factories. Clinical experience and epidemiological studies have demonstrated that cobalt exposure may lead to severely impaired lung function, i.e. hard metal lung disease and occupational cobalt-related asthma, contact dermatitis and cardiovascular effects. However, the evidence for the carcinogenicity of cobalt and cobalt compounds is considered inadequate (IARC, 1991). Most frequently, exposure to cobalt occurs simultaneously with exposure to other elements known to pose a health risk, (e.g. nickel, arsenic, chromium, tungsten). The importance of cobalt as sole causal agent in hard metal lung diseases, cardiomyopathy and cancer are still a matter of controversy. In the two Danish porcelain factories, cobalt blue underglaze dyes have been used since 1888. In contrast to the exposure experience of hard metal factories, the exposure of plate painters occurs with only low trace levels of other potentially harmful compounds such as the carcinogenic metals nickel, arsenic and chromium. Consequently, the nearly-pure cobalt exposure makes the plate painters an attractive group for studies on the health effects of cobalt. During the period 1982-1992 the surveillance programme showed a profound reduction in the urine level of cobalt (Co-U) from 100-fold to 10-fold above the median level of the unexposed control subjects. In the same period, the airborne cobalt exposure declined from 1356 nmol/m3 to 454 nmol/m3, the Danish occupational exposure limit being 845 nmol/m3. In 1982, when the cobalt exposure was above the occupational exposure limit, the plate painters showed a chronic impaired lung function. The obstructive effects may be similar to some of the effects observed in hard metal workers. In 1988, a study on the effect of cobalt exposure at low levels revealed no inhibitory effects on thyroid function, but the ratio between T4 and T3 increased, indicating that low cobalt exposure may have an impact on the metabolism of thyroid hormones. Parallel studies were conducted on the metabolism and excretion of cobalt. The gastrointestinal uptake of soluble CoCl was considerably higher than the uptake of insoluble cobalt(II) oxide. In addition, it was demonstrated that ingestion of controlled amounts of the soluble cobalt compound resulted in significantly higher concentrations of cobalt in urine and blood (Co-B) from females compared with males (P
In recent years, a focus on workers' ability, rather than impairment, has guided disability management services. However, a challenge with the notion of 'ability' is identification of the border between ability and inability. This article considers this gray zone of disability management in the case of a workers' compensation vocational retraining program for injured workers in Ontario.
In-depth interviews and focus groups were conducted with a purposive sample of 71 participants who were directly involved with the vocational retraining process. Workers in the program had on average incurred injury 3 years earlier. Procedural and legal documents were also analyzed. Principles of grounded theory and discourse analysis guided the data gathering and analysis.
A program focus on worker abilities did not allow for consideration of unresolved medical problems. Concepts such as maximum medical rehabilitation distracted attention from workers' ongoing chronic and unstable health situations, and incentive levers to employers directed some of the least capable workers into the program. As well, communication pathways for discussing health problems were limited by rules and provider reluctance to reveal problems. Therefore, workers completing the program were deemed 'employable', while ongoing and problematic health conditions preventing employment remained relatively uncharted and invisible.
This study reinforces how the shift in disability management paradigm to a focus on ability and return to work requires consideration of environmental conditions, including policies and programs and implementation. A focus on the environment in which worker ability can be enacted might be as important as a focus on improving individual worker characteristics.
Long-term measures to reduce tobacco consumption in Australia have had differential effects in the population. The prevalence of smoking in Aboriginal peoples is currently more than double that of the non-Aboriginal population. Aboriginal Health Workers are responsible for providing primary health care to Aboriginal clients including smoking cessation programs. However, Aboriginal Health Workers are frequently smokers themselves, and their smoking undermines the smoking cessation services they deliver to Aboriginal clients. An understanding of the barriers to quitting smoking experienced by Aboriginal Health Workers is needed to design culturally relevant smoking cessation programs. Once smoking is reduced in Aboriginal Health Workers, they may then be able to support Aboriginal clients to quit smoking.
We undertook a fundamental qualitative description study underpinned by social ecological theory. The research was participatory, and academic researchers worked in partnership with personnel from the local Aboriginal health council. The barriers Aboriginal Health Workers experience in relation to quitting smoking were explored in 34 semi-structured interviews (with 23 Aboriginal Health Workers and 11 other health staff) and 3 focus groups (n = 17 participants) with key informants. Content analysis was performed on transcribed text and interview notes.
Aboriginal Health Workers spoke of burdensome stress and grief which made them unable to prioritise quitting smoking. They lacked knowledge about quitting and access to culturally relevant quitting resources. Interpersonal obstacles included a social pressure to smoke, social exclusion when quitting, and few role models. In many workplaces, smoking was part of organisational culture and there were challenges to implementation of Smokefree policy. Respondents identified inadequate funding of tobacco programs and a lack of Smokefree public spaces as policy level barriers. The normalisation of smoking in Aboriginal society was an overarching challenge to quitting.
Aboriginal Health Workers experience multilevel barriers to quitting smoking that include personal, social, cultural and environmental factors. Multidimensional smoking cessation programs are needed that reduce the stress and burden for Aboriginal Health Workers; provide access to culturally relevant quitting resources; and address the prevailing normalisation of smoking in the family, workplace and community.
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Humpback whales (Megaptera novaeangliae) were hunted commercially in Canada's Pacific region until 1966. Depleted to an estimated 1,400 individuals throughout the North Pacific, humpback whales are listed as Threatened under Canada's Species at Risk Act (SARA) and Endangered under the US Endangered Species Act. We conducted an 8-year photo-identification study to monitor humpback whale usage of a coastal fjord system in British Columbia (BC), Canada that was recently proposed as candidate critical habitat for the species under SARA. This participatory research program built collaborations among First Nations, environmental non-governmental organizations and academics. The study site, including the territorial waters of Gitga'at First Nation, is an important summertime feeding destination for migratory humpback whales, but is small relative to the population's range. We estimated abundance and survivorship using mark-recapture methods using photographs of naturally marked individuals. Abundance of humpback whales in the region was large, relative to the site's size, and generally increased throughout the study period. The resulting estimate of adult survivorship (0.979, 95% CI: 0.914, 0.995) is at the high end of previously reported estimates. A high rate of resights provides new evidence for inter-annual site fidelity to these local waters. Habitat characteristics of our study area are considered ecologically significant and unique, and this should be considered as regulatory agencies consider proposals for high-volume crude oil and liquefied natural gas tanker traffic through the area. Monitoring population recovery of a highly mobile, migratory species is daunting for low-cost, community-led science. Focusing on a small, important subset of the animals' range can make this challenge more tractable. Given low statistical power and high variability, our community is considering simpler ecological indicators of population health, such as the number of individuals harmed or killed each year by human activities, including ship strikes and entanglement in fishing gear.
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Cites: Biol Lett. 2011 Apr 23;7(2):299-30220943678
Persons with severe mental illness (e.g. schizophrenia, bipolar disorder) have a high prevalence of somatic conditions compared to the general population. Mortality data in the Nordic countries reveal that these persons die 15-20 years earlier than the general population. Some factors explaining this high prevalence may be related to the individuals in question; others arise from the health care system's difficulty in offering somatic health care to these patient groups. The aim of the present study was therefore to explore the experiences and views of patients, relatives and clinicians regarding individual and organizational factors which facilitate or hinder access to somatic health care for persons with severe mental illness.
Flexible qualitative design. Data was collected by means of semi-structured individual interviews with patients with severe mental illness, relatives and clinicians representing primary and specialized health care. In all, 50 participants participated.
The main barrier to accessing somatic care is the gap between the organization of the health care system and the patients' individual health care needs. This is observed at both individual and organizational level. The health care system seems unable to support patients with severe mental illness and their psychiatric-somatic comorbidity. The main facilitators are the links between severe mental illness patients and medical departments. These links take the form of functions (i.e. systems which ensure that patients receive regular reminders), or persons (i.e. professional contacts who facilitate patients' access the health care).
Health care services for patients with severe mental illness need reorganization. Organizational structures and systems that facilitate cooperation between different departments must be put in place, along with training for health care professionals about somatic disease among psychiatric patients. The links between individual and organizational levels could be strengthened by introducing professional contacts, such as liaison physicians and case managers. This is also important to reduce stress and responsibility among relatives.
A statistical and epidemiological review of British Columbia native Indian and non-Indian mortality revealed that accidents were the leading cause of death among Indians but ranked only fourth among non-Indians. Comparison of accidental death rates by age and sex showed that, without exception, the rates among Indians were considerably higher than the corressponding rates for non-Indians. While the Indians represented some 2% of the total population of British Columbia, they accounted for over 10% of the total accident fatalities, 29% of drownings, and 21% of fatal burns.Socioeconomic, environmental and psychosocial factors and excessive drinking are considered the chief causes responsible for this rather unusual epidemiological phenomenon.This study revealed certain hazardous conditions which are specific to the Indian's present way of life. In the authors' opinion the recognition of these specific hazards is imperative for the planning of effective preventive campaigns.
Cites: Can J Public Health. 1962 Oct;53:409-1213992080
Accidental exposure to peanut has been reported to occur frequently. Total avoidance of peanut is difficult because of its widespread use, manufacturing and labeling errors, utensil contamination, and label misinterpretation.
Given the apparent increased awareness of peanut allergy by both consumers and food manufacturers, we aimed to determine the current frequency of accidental exposures occurring in peanut allergic children in Quebec and to identify factors associated with exposure.
The parents of children with peanut allergy diagnosed at the Montreal Children's Hospital completed questionnaires about accidental exposure to peanut occurring over the period of the preceding year. Logistic regression was used to identify associated factors.
Of 252 children, 62% were boys, with a mean age of 8.1 years (SD, 2.9). The mean age at diagnosis was 2.0 years (SD, 2.1). Thirty-five accidental exposures occurred in 29 children over a period of 244 patient-years, yielding an annual incidence rate of 14.3% (95% CI, 10.0% to 19.9%). Fifteen reactions were mild, 16 moderate, and 4 severe. Of 20 reactions that were moderate to severe, only 4 received epinephrine. Eighty percent of children attended schools prohibiting peanut, and only 1 accidental exposure occurred at school. No associated factors were identified.
Accidental exposure to peanut occurs at a lower frequency than previously reported, but most reactions are managed inappropriately.
Enhanced awareness, access to safer environments, and good food manufacturing practices may have contributed to a lower incidence of inadvertent peanut exposure, but a further reduction and better education on allergy management are desirable.