Frequency of workplace incidents and injuries in veterinarians, veterinary nurses and veterinary students and measures to control these.

BACKGROUND: Veterinarians, veterinary nurses and veterinary students work and train in a variety of environments and are exposed to a wide range of hazards. OBJECTIVES: (1) To compare the rate of health and safety incidents and injuries between veterinarians, veterinary nurses and veterinary students. (2) To investigate the health and safety hazard controls present in Australian veterinary workplaces. STUDY DESIGN: A cross-sectional study, using an online questionnaire. METHODS: Anonymous links to the questionnaire were disseminated to Australian veterinarians, veterinary nurses and veterinary students. RESULTS: A total of 494 veterinarians, 484 veterinary nurses and 212 veterinary students completed the survey. Incidents and injuries were common, particularly sharps-related injuries and animal bites. Australian veterinary nurses and veterinarians experienced the studied incidents at similar rates to each other. Veterinary students experienced some incidents and injuries at rates higher than both veterinarians and veterinary nurses, including heatstroke, hypothermia, sunburn, electric shock, loss of consciousness, being rammed or pushed over by an animal and farm equipment injuries. Of the workplace hazard controls reported, first aid boxes were most commonly present, and safety meetings occurred least commonly. Veterinary nurses received Q fever and rabies vaccines much less frequently than veterinarians and veterinary students. CONCLUSION: This study demonstrated that improvements need to be made to the occupational health and safety standards in the Australian veterinary sector. Veterinarians and veterinary nurses had suboptimal rates of access to many of the required and critical workplace health and safety controls. Improvements to the standard of health and safety training of veterinary students are indicated, given their higher rates of certain incidents and injury.

Hypothesis: A perfect day conveys internal time.

In 2007 the International Agency for Research on Cancer [IARC] concluded "shift work that involves circadian disruption is probably carcinogenic to humans" (Group 2A). To investigate the "probable" causal link, information on individual chronobiology is needed to specify exposures to circadian disruption associated with shift work. In epidemiological studies this information is usually assessed by questionnaire. The most widely used Morningness-Eveningness-Questionnaire (MEQ) and MunichChronoTypeQuestionnaire (MCTQ) reveal information on circadian type (MEQ) and actual sleep behaviour (MCTQ). As a further option we suggest to obtain preferred sleep times by using what we call the perfect day (PD) approach. We hypothesize that a PD - as a day of completely preferred sleep behaviour - captures pristine internal time. We argue that the PD approach may measure internal time more accurately than the MEQ and MCTQ which convey influences by work and social time pressures. The PD approach may therefore reduce misclassifications of internal time and reveal circadian disruption caused by different shift systems.

A telephone survey of factors affecting willingness to participate in health research surveys.

BACKGROUND: In recent years, reduced participation has been encountered across all epidemiological study designs, both in terms of non-response as well as refusal. A low response rate may reduce the statistical power but, more importantly, results may not be generalizable to the wider community. METHODS: In a telephone survey of 1413 randomly selected members of the Australian general population and of 690 participants sourced from previous studies, we examined factors affecting people's stated willingness to participate in health research. RESULTS: The majority of participants (61 %) expressed willingness to participate in health research in general but the percentage increased when provided with more specific information about the research. People were more willing if they have personal experience of the disease under study, and if the study was funded by government or charity rather than pharmaceutical companies. Participants from previous studies, older people and women were the groups most willing to participate. Younger men preferred online surveys, older people a written questionnaire, and few participants in any age and sex groups preferred a telephone questionnaire. CONCLUSION: Despite a trend toward reduced participation rates, most participants expressed their willingness to participate in health research. However, when seeking participants, researchers should be concrete and specific about the nature of the research they want to carry out. The preferred method of recommended contact varies with the demographic characteristics.

Childhood brain tumours: associations with parental occupational exposure to solvents.

BACKGROUND: Parental occupational exposures have been associated with childhood brain tumours (CBT), but results are inconsistent. Few studies have studied CBT risk and parental solvent exposure, suggesting a possible association. We examined the association between CBT and parental occupational exposure to solvents in a case-control study. METHODS: Parents of 306 cases and 950 controls completed detailed occupational histories. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for both maternal and paternal exposure to benzene, other aromatics, aliphatics and chlorinated solvents in key time periods relative to the birth of their child. Adjustments were made for matching variables (child's age, sex and state of residence), best parental education and occupational exposure to diesel exhaust. RESULTS: An increased risk of CBT was observed with maternal occupational exposures to chlorinated solvents (OR=8.59, 95% CI 0.94-78.9) any time before birth. Paternal exposure to solvents in the year before conception was associated with an increased CBT risk: OR=1.55 (95% CI 0.99-2.43). This increased risk appeared to be mainly attributable to exposure to aromatic solvents: OR=2.72 (95% CI 0.94-7.86) for benzene and OR=1.76 (95% CI 1.10-2.82) for other aromatics. CONCLUSIONS: Our results indicate that parental occupational exposures to solvents may be related to an increased risk of CBT.

The association between different night shiftwork factors and breast cancer: a case-control study.

BACKGROUND: Research on the possible association between shiftwork and breast cancer is complicated because there are many different shiftwork factors, which might be involved including: light at night, phase shift, sleep disruption and changes in lifestyle factors while on shiftwork (diet, physical activity, alcohol intake and low sun exposure). METHODS: We conducted a population-based case-control study in Western Australia from 2009 to 2011 with 1205 incident breast cancer cases and 1789 frequency age-matched controls. A self-administered questionnaire was used to collect demographic, reproductive, and lifestyle factors and lifetime occupational history and a telephone interview was used to obtain further details about the shiftwork factors listed above. RESULTS: A small increase in risk was suggested for those ever doing the graveyard shift (work between midnight and 0500 hours) and breast cancer (odds ratio (OR)=1.16, 95% confidence interval (CI)=0.97-1.39). For phase shift, we found a 22% increase in breast cancer risk (OR=1.22, 95% CI=1.01-1.47) with a statistically significant dose-response relationship (P=0.04). For the other shiftwork factors, risks were marginally elevated and not statistically significant. CONCLUSION: We found some evidence that some of the factors involved in shiftwork may be associated with breast cancer but the ORs were low and there were inconsistencies in duration and dose-response relationships.

Lifestyle factors associated with survival after colorectal cancer diagnosis.

BACKGROUND: Aside from tumour stage and treatment, little is known about potential factors that may influence survival in colorectal cancer patients. The aim of this study was to investigate the associations between physical activity, obesity and smoking and disease-specific and overall mortality after a colorectal cancer diagnosis. METHODS: A cohort of 879 colorectal cancer patients, diagnosed in Western Australia between 2005 and 2007, were followed up to 30 June 2012. Cox's regression models were used to estimate the hazard ratios (HR) for colorectal cancer-specific and overall mortality associated with self-reported pre-diagnosis physical activity, body mass index (BMI) and smoking. RESULTS: Significantly lower overall and colorectal cancer-specific mortality was seen in females who reported any level of recent physical activity than in females reporting no activity. The colorectal cancer-specific mortality HR for increasing levels of physical activity in females were 0.34 (95% CI=0.15, 0.75), 0.37 (95% CI=0.17, 0.81) and 0.41 (95% CI=0.18, 0.90). Overweight and obese women had almost twice the risk of dying from any cause or colorectal cancer compared with women of normal weight. Females who were current smokers had worse overall and colorectal cancer-specific mortality than never smokers (overall HR=2.64, 95% CI=1.18, 5.93; colorectal cancer-specific HR=2.70, 95% CI=1.16, 6.29). No significant associations were found in males. CONCLUSION: Physical activity, BMI and smoking may influence survival after a diagnosis of colorectal cancer, with more pronounced results found for females than for males.

Cancer incidence and mortality among underground and surface goldminers in Western Australia.

BACKGROUND: In a cohort of goldminers, we estimated cancer mortality and incidence, for both surface and underground workers, and we examined the hypothesis that (underground) mining may be protective against prostate cancer. METHODS: Standardised mortality and incidence ratios (SMRs and SIRs) and 95% confidence intervals (CI) were calculated to compare cancer mortality and incidence of former goldminers with that of the general male population. Internal comparisons on duration of underground work were examined using Cox regression. RESULTS: During 52 608 person-years of follow-up among 2294 goldminers, 1922 deaths were observed. For any cancer, mortality was increased for the total group of miners (SMR=1.27, 95% CI 1.16-1.39). In the Cox models, lung cancer mortality and incidence were particularly increased among underground miners, even after adjustment for smoking. The SMR for prostate cancer suggested a lower risk for underground miners, whereas incidence of prostate cancer was significantly increased (SIR=1.31, 95% CI 1.07-1.60) among underground miners. CONCLUSION: Overall cancer mortality and incidence was higher among Western Australian goldminers compared with the general male population, particularly for underground mining. This study does not support the hypothesis that miners have a decreased risk of prostate cancer.

Mental health in female veterinarians: effects of working hours and having children.

BACKGROUND: Personal, interpersonal and organisational factors have been suggested as possible causes of stress, anxiety and depression for veterinarians. We used established psychological scales to measure (1) levels of distress and work-related stress (anxiety and depression) and (2) the demographic and work characteristics of female veterinarians in relation to anxiety, depression and mental health. METHODS: A national cross-sectional survey of a cohort population was conducted and self-administered questionnaires were received from 1017 female veterinarians who completed the mental health section of the survey. Using linear and logistic regression analyses, we examined demographic and work-related factors associated with overall stress measured by the General Health Questionnaire scale and the Affective Well-Being scale (Anxiety-Contentment Axis and Depression-Enthusiasm Axis). RESULTS: More than one-third (37%) of the sample was suffering 'minor psychological distress', suggesting the stressful nature of veterinary practice. Women with two or more children had less anxiety and depression compared with those who had never been pregnant or were childless. Longer working hours were associated with increased anxiety and depression in female veterinarians overall and in stratified samples of women with and without children. CONCLUSION: Among the work characteristics of veterinary practice, long working hours may have a direct effect on a veterinarian's health in terms of anxiety, depression and mental health. The finding also indicates that women with two or more children have less anxiety and depression than women who have never been pregnant or childless women.

Serious injuries to Australian veterinarians working with cattle.

OBJECTIVE: To describe the factors associated with serious injuries sustained during cattle-associated activities by veterinarians responding to the Health Risks of Australian Veterinarians (HRAV) survey. METHODS: Responses from the HRAV survey were reviewed and the factors associated with serious injuries reported by veterinarians while working with cattle were analysed. All veterinarians who had graduated from Australian veterinary schools between 1960 and 2000 were eligible for inclusion in the survey. RESULTS: The survey identified 474 serious injuries sustained while undertaking cattle-associated activities. Most cattle-associated injuries (82%) were sustained in stock or handling yards and 57% of reported injuries were sustained while undertaking pregnancy testing or undertaking examinations. Nearly 80% of all cattle-associated injuries were sustained as a result of the veterinarian being kicked or struck (49%) or pushed against or stepped on (30%). The part of the body most commonly injured was the upper limbs. Fractures were the most common type of serious injury sustained. The use of safety precautions at the time of the injury was reported by 62% of those veterinarians reporting injury. CONCLUSIONS: This study describes factors associated with serious injuries while working with cattle, as reported by veterinarians responding to the HRAV survey. Findings from this study will facilitate discussions aimed at addressing injury prevention for cattle veterinarians, including improving the awareness of safe handling practices and safety precautions.

Breast cancer among Yemeni women using the National Oncology Centre Registry 2004-2010.

BACKGROUND: In developing countries including Arab countries breast cancer is one of the most common cancers found in women. Even though breast cancer incidence is lower in Arab developing countries than in western countries, Arabic women are more likely to be diagnosed at an earlier age than the women in western countries. METHOD: A descriptive study was undertaken to investigate the type of breast cancer, lymph node involvement, side of breast and, region and age distribution of breast cancer patients registered in the National Oncology Centre in Yemen. RESULTS: From September 2004 to December 2010, 2654 women across Yemen diagnosed with breast cancer were registered in the National Oncology Centre for treatment. Between the years 2004 and 2010, breast cancer represented 22% of all cancers registered in women. Seventy-one per cent of the women were aged 50 or younger at the time of diagnosis. The most common age group affected was women aged 41-50 years, with (35%) of cases occurring in this age. Invasive ductal carcinoma was the most common pathology (76%) and 79% of the patients had lymph node involvement at the time of diagnosis. Approximately 2% had bilateral disease and the frequency of left (44%) and right breast cancer (42%) were similar. CONCLUSION: This study has shown that breast cancer is a disease of young women in Yemen. The majority of women presented with lymph node involvement. Hence efforts are needed to increase breast cancer awareness in Yemen for early detection at all age groups, and to target women living in areas that have lower access to health care services.

Risk of childhood acute lymphoblastic leukaemia following parental occupational exposure to extremely low frequency electromagnetic fields.

BACKGROUND: Earlier studies have reported moderate increases in the risk of acute lymphoblastic leukaemia (ALL) among children whose mothers have been occupationally exposed to extremely low frequency (ELF) electromagnetic fields. Other studies examining parental occupational exposure to ELF and ALL have reported mixed results. METHODS: In an Australian case-control study of ALL in children aged < 15 years, parents were asked about tasks they undertook in each job. Exposure variables were created for any occupational exposure before the birth of the child, in jobs 2 years before birth, in jobs 1 year before birth and up to 1 year after birth. RESULTS: In all, 379 case and 854 control mothers and 328 case and 748 control fathers completed an occupational history. Exposure to ELF in all time periods was similar in case and control mothers. There was no difference in exposure between case and control fathers. There was no association between maternal (odds ratio (OR)=0.96; 95% CI=0.74-1.25) or paternal (OR=0.78; 95% CI=0.56-1.09) exposure to ELF any time before the birth and risk of childhood ALL. CONCLUSION: We did not find an increased risk of ALL in offspring of parents with occupational exposure to ELF.

Second cancer incidence and cancer mortality among chronic lymphocytic leukaemia patients: a population-based study.

BACKGROUND: Patients with chronic lymphocytic leukaemia (CLL) are known to have increased risks of second cancer. The incidence of second cancers after CLL has not been reported in detail for Australia, a country with particularly high levels of ultraviolet radiation (UVR). METHODS: The study cohort comprised of all people diagnosed with a primary CLL between 1983 and 2005 in Australia. Standardised incidence ratios (SIRs) and standardised mortality ratios (SMRs) were calculated using Australian population rates. RESULTS: Overall, the risk of any second incident cancer was more than double that of the general population (SIR=2.17, 95% confidence interval (CI)=2.07, 2.27) and remained elevated for at least 9 years after CLL. Risks were increased for many cancers, particularly melanoma (SIR=7.74, 95% CI=6.85, 8.72). The risk of melanoma increased at younger ages, but was constant across >9 years of follow-up. Chronic lymphocytic leukaemia patients also had an increased risk of death because of melanoma (SMR=4.79, 95% CI=3.83, 5.90) and non-melanoma skin cancer (NMSC; SMR=17.0, 95% CI=14.4, 19.8), suggesting that these skin cancers may be more aggressive in CLL patients. CONCLUSION: We speculate that a shared risk factor, such as general immune suppression, modulated by UVR exposure may explain the increased risk of melanoma and NMSC in CLL patients.

Hypotheses for mechanisms linking shiftwork and cancer.

Shift work has been associated with various adverse health outcomes. In particular, there has been a recent flourish in investigating potential cancer risk associated with working night shifts and other shift schedules. Epidemiologic studies have revealed generally weak associations due to several methodological challenges such as lack of standard classifications of shift or night work. The field also has been hindered by a lack of clarity about the possible mechanisms by which shiftwork could have an effect on cancer risk. One possible mechanism is reduced production of melatonin caused by exposure to light at night. Although there is a growing body of evidence that provides some support for this mechanism, several other mechanisms also make sense from a biological point of view. Further, the relatively weak magnitude of the associations between light at night and melatonin level suggests that multiple factors may be operating along the pathway between shift work and adverse health consequences (including cancer risk). Here we propose four additional mechanisms that should be considered for a comprehensive investigation of these potential pathways. These are: phase shift; sleep disruption; lifestyle factors (such as poor quality diets, less physical activity and higher BMI); and lower vitamin D. Consideration of all these mechanisms is necessary in order to design effective preventative workplace strategies. In developed countries, approximately 20% of the population undertake shiftwork and, while we are unlikely to be able to eliminate shiftwork from current work practices, there are aspects of shiftwork that can be modified and there may be facets of individual susceptibility that we may be able to identify and target for prevention.

Merkel cell carcinoma in Western Australia: a population-based study of incidence and survival.

BACKGROUND: Merkel cell carcinoma (MCC) is an uncommon but aggressive cutaneous skin cancer. Even with the appropriate treatment, MCC is prone to recurrence, and metastases are common. Exposure to ultraviolet radiation has been suggested as contributing towards the development of MCC. MCC has not been extensively investigated in Australia, even though Australia has the highest incidence of sun-related cancers in the world. OBJECTIVES: To describe the demographics and determine trends of incidence and survival of MCC cases in Western Australia (WA). METHODS: All reported invasive cases of MCC incident between 1 January 1993 and 31 December 2007 were extracted from the WA Cancer Registry. Age-adjusted incidence rates for MCC were calculated using direct standardization to the U.S. standard 2000 population. Cause-specific survival was investigated using Kaplan-Meier and Cox proportional hazards analysis. results: Two hundred and fifteen cases were confirmed by pathological review as being definite cases of MCC. Patients were mainly males (65%) and elderly (median age 77 years). Standardized age-adjusted incidence rates were higher in men (1·0/100,000) than in women (0·63/100,000) and higher in older ages (15·5/100,000 in the 85+year age group) than younger ages (0·1/100,000 in the 30-34 year age group). Five-year cause-specific survival was 64%. CONCLUSIONS: Incidence of MCC in WA is the highest reported in the literature. In addition, MCC has worse survival than melanoma. The high rates and demographic and anatomical distribution are consistent with sun exposure playing a causal role.

Meat consumption and cooking practices and the risk of colorectal cancer.

BACKGROUND/OBJECTIVES: The association between meat consumption and the risk of colorectal cancer (CRC) has been controversial. One of the difficulties in determining this association has been measurement of different attributes of meat consumption, including cooking methods and level of doneness. SUBJECTS/METHODS: We investigated the association between meat consumption and cooking practices and the risk of CRC in a population-based case-control study in the Western Australian Bowel Health Study. From July 2005 to February 2007, 567 incident CRC cases and 713 controls, who were frequency matched to cases for age- and sex, completed questionnaires on lifestyle and meat consumption. Estimated odds ratios (ORs) comparing meat consumption quartile groups were obtained from multivariate logistic regression models. RESULTS: The amount of red baked meat consumed had a statistically significant inverse trend of association with CRC (Q4 OR=0.73 95% confidence interval 0.53-1.01). When frequency was multiplied by serving size and by doneness, the association remained protective but was no longer statistically significant. The protective trends for red pan-fried meat were also borderline statistically significant. There were no other statistically significant or meaningful associations with any of the types of meat cooked by any method and the risk of CRC. CONCLUSIONS: Our data do not support the hypothesis that meat consumption is a risk factor for CRC.

Screening for breast cancer post reduction mammoplasty.

AIM: To investigate whether remodelling of the breast after breast reduction surgery has an effect on mammographic cancer detection. METHODS AND MATERIALS: For women who attended population-based screening between January 1998 to December 2007, data were extracted on their age, history of previous breast reduction, and the result of screening (recall for further assessment, cancer, or no cancer). The number of cancers detected, recalls per 1000 screens and the characteristics of the cancers detected in the two groups was compared. RESULTS: In total 244,147 women with 736,219 screening episodes were reviewed. In the 4743 women who had a breast reduction, 51 breast cancers were detected [age standardized rate (ASR) of 4.28 per 1000 screening episodes; 95% CI 3.11-5.46], compared with 4342 breast cancers in 239 404 women screened in the non-reduction group (ASR of 5.99 per 1000 screening episodes; 95% CI 5.81-6.16). There were fewer cancers in the breast reduction group with a relative risk of 0.71. There was no significant difference in the rate of recall between the two groups, with a crude recall rate of 46.1 per 1000 screening episodes post-breast reduction compared with 50.7 per 1000 screening episodes for women without breast reduction. There was no significant difference in the pathological type or location of the cancer between the two groups of women. CONCLUSION: Postoperative breast changes following reduction mammoplasty do not significantly hinder analysis of the screening mammogram.

Occupational causes of testicular cancer in adults.

Testicular cancer is one of the commonest cancers in men of working age, and is increasing in incidence in Europe and North America. One suggested mechanism of causation is that there is impaired differentiation of germ cells in the pre- or perinatal period, followed by malignant transformation in later life, possibly by a hormonal mechanism. Endocrine disrupting chemicals (EDCs) have been a major focus of interest for etiological research into testicular cancer because they interact with various hormonal pathways. Several EDCs including bisphenol A, phthalates, metals, polychlorinated biphenyls, and organochlorines have been investigated, but there are few studies and those that exist have not been able to assess exposure well. In addition, several studies, particularly those with better exposure assessment, have suggested that workers in electrical occupations have increased risks of testicular cancer. Electromagnetic radiation may have subthermal effects or may disrupt hormone release. Chronodisruption such as due to shift-work could potentially increase the risk of testicular cancer via disruption of hormonal cycles, but only one study has so far investigated this possibility. Lastly, solvent exposure, particularly to dimethylformamide, has been suggested to be associated with testicular cancer, but almost all these studies are based on job title only, with no specific assessment of solvent exposure. In conclusion, there is little evidence available on which to base definitive statements about occupational causes of testicular cancer. Future studies need to improve exposure assessment and develop ways to adjust for possible prenatal factors.