Prevalent occupational exposures and risk of lung cancer among women: Results from the application of the Canadian Job-Exposure Matrix (CANJEM) to a combined set of ten case-control studies.

BACKGROUND: Worldwide, lung cancer is the second leading cause of cancer death in women. The present study explored associations between occupational exposures that are prevalent among women, and lung cancer. METHODS: Data from 10 case-control studies of lung cancer from Europe, Canada, and New Zealand conducted between 1988 and 2008 were combined. Lifetime occupational history and information on nonoccupational factors including smoking were available for 3040 incident lung cancer cases and 4187 controls. We linked each reported job to the Canadian Job-Exposure Matrix (CANJEM), which provided estimates of probability, intensity, and frequency of exposure to each selected agent in each job. For this analysis, we selected 15 agents (cleaning agents, biocides, cotton dust, synthetic fibers, formaldehyde, cooking fumes, organic solvents, cellulose, polycyclic aromatic hydrocarbons from petroleum, ammonia, metallic dust, alkanes C18+, iron compounds, isopropanol, and calcium carbonate) that had lifetime exposure prevalence of at least 5% in the combined study population. For each agent, we estimated lung cancer risk in each study center for ever-exposure, by duration of exposure, and by cumulative exposure, using separate logistic regression models adjusted for smoking and other covariates. We then estimated the meta-odds ratios using random-effects meta-analysis. RESULTS AND CONCLUSIONS: None of the agents assessed showed consistent and compelling associations with lung cancer among women. The following agents showed elevated odds ratio in some analyses: metallic dust, iron compounds, isopropanol, and organic solvents. Future research into occupational lung cancer risk factors among women should prioritize these agents.

Long working hours, sedentary work, noise, night shifts and risk of ischaemic heart disease.

OBJECTIVE: Ischaemic heart disease (IHD) is a leading cause of death in Western countries. The aim of this study was to examine the associations between occupational exposure to loud noise, long working hours, shift work, and sedentary work and IHD. METHODS: This data linkage study included all New Zealanders employed and aged 20-64 years at the time of the 2013 census, followed up for incident IHD between 2013 and 2018 based on hospitalisation, prescription and death records. Occupation and number of working hours were obtained from the census, and exposure to sedentary work, loud noise and night shift work was assessed using New Zealand job exposure matrices. HRs were calculated for males and females using Cox regression adjusted for age, socioeconomic status, smoking and ethnicity. RESULTS: From the 8 11 470 males and 7 83 207 females employed at the time of the census, 15 012 male (1.9%) and 5595 female IHD cases (0.7%) were identified. For males, there was a modestly higher risk of IHD for the highest category (>90 dBA) of noise exposure (HR 1.19; 95% CI 1.07 to 1.33), while for females exposure prevalence was too low to calculate an HR. Night shift work was associated with IHD for males (HR 1.10; 95% CI 1.05 to 1.14) and females (HR 1.25; 95% CI 1.17 to 1.34). The population attributable fractions for night shift work were 1.8% and 4.6%, respectively. No clear associations with working long hours and sedentary work were observed. CONCLUSIONS: This study suggests that occupational exposures to high levels of noise and night shift work might be associated with IHD risk.

Herbicide use in farming and other jobs in relation to non-Hodgkin's lymphoma (NHL) risk.

OBJECTIVES: Given mixed evidence for carcinogenicity of current-use herbicides, we studied the relationship between occupational herbicide use and risk of non-Hodgkin's lymphoma (NHL) in a large, pooled study. METHODS: We pooled data from 10 case-control studies participating in the International Lymphoma Epidemiology Consortium, including 9229 cases and 9626 controls from North America, the European Union and Australia. Herbicide use was coded from self-report or by expert assessment in the individual studies, for herbicide groups (eg, phenoxy herbicides) and active ingredients (eg, 2,4-dichlorophenoxyacetic acid (2,4-D), glyphosate). The association between each herbicide and NHL risk was estimated using logistic regression to produce ORs and 95% CIs, with adjustment for sociodemographic factors, farming and other pesticides. RESULTS: We found no substantial association of all NHL risk with ever-use of any herbicide (OR=1.10, 95% CI: 0.94 to 1.29), nor with herbicide groups or active ingredients. Elevations in risk were observed for NHL subtypes with longer duration of phenoxy herbicide use, such as for any phenoxy herbicide with multiple myeloma (>25.5 years, OR=1.78, 95% CI: 0.74 to 4.27), 2,4-D with diffuse large B-cell lymphoma (>25.5 years, OR=1.47, 95% CI: 0.67 to 3.21) and other (non-2,4-D) phenoxy herbicides with T-cell lymphoma (>6 years, lagged 10 years, OR=3.24, 95% CI: 1.03 to 10.2). An association between glyphosate and follicular lymphoma (lagged 10 years: OR=1.48, 95% CI: 0.98 to 2.25) was fairly consistent across analyses. CONCLUSIONS: Most of the herbicides examined were not associated with NHL risk. However, associations of phenoxy herbicides and glyphosate with particular NHL subtypes underscore the importance of estimating subtype-specific risks.

Neuropsychological symptoms in workers handling cargo from shipping containers and export logs.

PURPOSE: Acute poisonings of workers handling shipping containers by fumigants and other harmful chemicals off-gassed from cargo have been reported but (sub)-chronic neuropsychological effects have not been well studied. METHODS: This cross-sectional study assessed, using standardised questionnaires, current (past 3-months) neuropsychological symptoms in 274 container handlers, 38 retail workers, 35 fumigators, and 18 log workers, all potentially exposed to fumigants and off-gassed chemicals, and a reference group of 206 construction workers. Prevalence odds ratios (OR), adjusted for age, ethnicity, smoking, alcohol consumption, education, personality traits and BMI, were calculated to assess associations with the total number of symptoms (≥ 3, ≥ 5 or ≥ 10) and specific symptom domains (neurological, psychosomatic, mood, memory/concentration, fatigue, and sleep). RESULTS: Compared to the reference group, exposed workers were more likely to report ≥ 10 symptoms, statistically significant only for retail workers (OR 6.8, 95% CI 1.9-24.3) who also reported more fatigue (OR 10.7, 95% CI 2.7-42.7). Container handlers with the highest exposure-duration were more likely to report ≥ 10 symptoms, both when compared with reference workers (OR 4.0, 95% CI 1.4-11.7) and with container handlers with shorter exposure duration (OR 7.5, 95% CI 1.7-32.8). The duration of container handling was particularly associated with symptoms in the memory/concentration domain, again both when compared to reference workers (OR 8.8, 95% CI 2.5-31.4) and workers with the lowest exposure-duration (OR 6.8, 95% CI 1.5-30.3). CONCLUSION: Container handlers may have an increased risk of neuropsychological symptoms, especially in the memory/concentration domain. Retail workers may also be at risk, but this requires confirmation in a larger study.

Sports and trauma as risk factors for Motor Neurone Disease: New Zealand case-control study.

OBJECTIVES: To assess whether sports, physical trauma and emotional trauma are associated with motor neurone disease (MND) in a New Zealand case-control study (2013-2016). METHODS: In total, 321 MND cases and 605 population controls were interviewed collecting information on lifetime histories of playing sports, physical trauma (head injury with concussion, spine injury) and emotional trauma (14 categories). ORs were estimated using logistic regression adjusting for age, sex, ethnicity, socioeconomic status, education, smoking status, alcohol consumption and mutually adjusting for all other exposures. RESULTS: Head injury with concussion ≥3 years before diagnosis was associated with MND (OR 1.51, 95% CI: 1.09-2.09), with strongest associations for two (OR 4.01, 95% CI: 1.82-8.86), and three or more (OR 2.34, 95% CI: 1.00-5.45) head injuries. Spine injury was not associated with MND (OR 0.81, 95% CI: 0.48-1.36). Compared to never playing sports, engaging in sports throughout childhood and adulthood increased MND risk (OR 1.81, 95% CI: 1.01-3.25), as was more than 12 years playing football/soccer (OR 2.35, 95% CI: 1.19-4.65). Reporting emotionally traumatic events in more than three categories was associated with MND (OR 1.88, 95% CI: 1.17-3.03), with physical childhood abuse the only specific emotional trauma associated with MND (OR 1.82, 95% CI: 1.14-2.90), particularly for those reporting longer abuse duration (OR(5-8 years) 2.26, 95% CI: 1.14-4.49; OR(>8 years) 3.01, 95% CI: 1.18-7.70). For females, having witnessed another person being killed, seriously injured or assaulted also increased MND risk (OR 2.68, 95% CI: 1.06-6.76). CONCLUSIONS: This study adds to the evidence that repeated head injury with concussion, playing sports in general, and playing football (soccer) in particular, are associated with an increased risk of MND. Emotional trauma, that is physical abuse in childhood, may also play a role.

Occupational exposures to pesticides and other chemicals: a New Zealand motor neuron disease case-control study.

OBJECTIVES: To assess associations between occupational exposures to pesticides and other chemicals and motor neuron disease (MND). METHODS: A population-based case-control study that included 319 MND cases (64% male/36% female) recruited through the New Zealand MND Association complemented with hospital discharge data, and 604 controls identified from the Electoral Roll. For each job held, a questionnaire collected information on 11 exposure categories (dust, fibres, tobacco smoke, fumes, gas, fumigants, oils/solvents, acids/alkalis, pesticides, other chemicals and animals/animal products). ORs were estimated using logistic regression adjusting for age, sex, ethnicity, socioeconomic status, education, smoking, alcohol consumption, physical activities, head/spine injury and other occupational exposures. RESULTS: Two exposure categories were associated with increased MND risks: pesticides (OR 1.70, 95% CI 1.17 to 2.48) and fumigants (OR 3.98, 95% CI 1.81 to 8.76), with risks increasing with longer exposure duration (p<0.01). Associations were also observed for: methyl bromide (OR 5.28, 95% CI 1.63 to 17.15), organochlorine insecticides (OR 3.28, 95% CI 1.18 to 9.07), organophosphate insecticides (OR 3.11, 95% CI 1.40 to 6.94), pyrethroid insecticides (OR 6.38, 95% CI 1.13 to 35.96), inorganic (copper) fungicides (OR 4.66, 95% CI 1.53 to 14.19), petrol/diesel fuel (OR 2.24, 95% CI 1.27 to 3.93) and unspecified solvents (OR 1.91, 95% CI 1.22 to 2.99). In women, exposure to textile fibres (OR 2.49, 95% CI 1.13 to 5.50), disinfectants (OR 9.66, 95% CI 1.29 to 72.44) and cleaning products (OR 3.53, 95% CI 1.64 to 7.59) were also associated with MND; this was not observed in men (OR 0.80, 95% CI 0.44 to 1.48; OR 0.72, 95% CI 0.29 to 1.84; OR 0.57, 95% CI 0.21 to 1.56, respectively). CONCLUSIONS: This study adds to the evidence that pesticides, especially insecticides, fungicides, and fumigants, are risk factors for MND.

A longitudinal linkage study of occupation and ischaemic heart disease in the general and Maori populations of New Zealand.

OBJECTIVES: Occupation is a poorly characterised risk factor for cardiovascular disease (CVD) with females and indigenous populations under-represented in most research. This study assessed associations between occupation and ischaemic heart disease (IHD) in males and females of the general and Maori (indigenous people of NZ) populations of New Zealand (NZ). METHODS: Two surveys of the NZ adult population (NZ Workforce Survey (NZWS); 2004-2006; n = 3003) and of the Maori population (NZWS Maori; 2009-2010; n = 2107) with detailed occupational histories were linked with routinely collected health data and followed-up until December 2018. Cox regression was used to calculate hazard ratios (HR) for IHD and "ever-worked" in any of the nine major occupational groups or 17 industries. Analyses were controlled for age, deprivation and smoking, and stratified by sex and survey. RESULTS: 'Plant/machine operators and assemblers' and 'elementary occupations' were positively associated with IHD in female Maori (HR 2.2, 95%CI 1.2-4.1 and HR 2.0, 1.1-3.8, respectively) and among NZWS males who had been employed as 'plant/machine operators and assemblers' for 10+ years (HR 1.7, 1.2-2.8). Working in the 'manufacturing' industry was also associated with IHD in NZWS females (HR 1.9, 1.1-3.7), whilst inverse associations were observed for 'technicians and associate professionals' (HR 0.5, 0.3-0.8) in NZWS males. For 'clerks', a positive association was found for NZWS males (HR 1.8, 1.2-2.7), whilst an inverse association was observed for Maori females (HR 0.4, 0.2-0.8). CONCLUSION: Associations with IHD differed significantly across occupational groups and were not consistent across males and females or for Maori and the general population, even within the same occupational groups, suggesting that current knowledge regarding the association between occupation and IHD may not be generalisable across different population groups.

Ischaemic Heart Disease and Occupational Exposures: A Longitudinal Linkage Study in the General and Maori Populations of New Zealand.

OBJECTIVES: This study assessed associations between occupational exposures and ischaemic heart disease (IHD) for males and females in the general and Maori populations (indigenous people of New Zealand). METHODS: Two surveys of the general adult [New Zealand Workforce Survey (NZWS); 2004-2006; n = 3003] and Maori population (Maori NZWS; 2009-2010; n = 2107), with information on occupational exposures, were linked with administrative health data and followed-up until December 2018. Cox proportional hazards regression (adjusted for age, deprivation, and smoking) was used to assess associations between organizational factors, stress, and dust, chemical and physical exposures, and IHD. RESULTS: Dust [hazard ratio (HR) 1.6, 95%CI 1.1-2.4], smoke or fumes (HR 1.5, 1.0-2.3), and oils and solvents (HR 1.5, 1.0-2.3) were associated with IHD in NZWS males. A high frequency of awkward or tiring hand positions was associated with IHD in both males and females of the NZWS (HRs 1.8, 1.1-2.8 and 2.4, 1.1-5.0, respectively). Repetitive tasks and working at very high speed were associated with IHD among NZWS females (HRs 3.4, 1.1-10.4 and 2.6, 1.2-5.5, respectively). Maori NZWS females working with vibrating tools and those exposed to a high frequency of loud noise were more likely to experience IHD (HRs 2.3, 1.1-4.8 and 2.1, 1.0-4.4, respectively). Exposure to multiple dust and chemical factors was associated with IHD in the NZWS males, as was exposure to multiple physical factors in males and females of the NZWS. CONCLUSIONS: Exposures associated with an elevated IHD risk included dust, smoke or fumes, oils and solvents, awkward grip or hand movements, carrying out repetitive tasks, working at very high speed, loud noise, and working with tools that vibrate. Results were not consistently observed for males and females and between the general and Maori populations.

Occupational insecticide exposure and risk of non-Hodgkin lymphoma: A pooled case-control study from the InterLymph Consortium.

Evidence for the human health effects of pesticides is needed to inform risk assessment. We studied the relationship between occupational insecticide use and risk of non-Hodgkin lymphoma (NHL) by pooling data from nine case-control studies participating in the InterLymph Consortium, including 7909 cases and 8644 controls from North America, the European Union and Australia. Insecticide use was coded using self-report or expert assessment, for insecticide groups (eg, organophosphates, pyrethroids) and active ingredients (eg, malathion, permethrin). Associations with insecticides were estimated using logistic regression to produce odds ratios (ORs) and 95% confidence intervals (CI) for all NHL and NHL subtypes, with adjustment for study site, demographic factors and use of other pesticides. Occupational insecticide use, overall, was not associated with risk of NHL. Use of organophosphate insecticides was associated with increased risk of all NHL and the subtype follicular lymphoma, and an association was found with diazinon, in particular (ever use: OR = 2.05, 95%CI: 1.24-3.37). The carbamate insecticide, carbaryl, was associated with risk of all NHL, and the strongest associations were found with T-cell NHL for ever-use (OR = 2.44, 95%CI: 1.13-5.28) and longer duration (>8 years vs never: OR = 2.90, 95%CI: 1.02-8.25). There was no association of NHL with other broad groups of insecticides, including organochlorines and pyrethroids, and some inverse associations were estimated in relation to historical DDT use. Our findings contribute to the totality of evidence available to help inform risk decisions by public health and regulatory agencies of importance given continued, widespread use of organophosphate and carbamate insecticides.

Total blood mercury and its determinants in New Zealand children and adults.

BACKGROUND: Mercury is a widespread persistent environmental pollutant associated with adverse health effects. OBJECTIVE: This first national biomonitoring survey of blood total mercury (tHg) conducted in New Zealand aimed to provide baseline data and identify exposure determinants. METHODS: Blood was collected from 191 children (age 5-18 years) and 304 adults (20-65) in 2014-2016 and analysed for tHg using inductively coupled plasma mass spectrometry. Linear regression was used to assess associations with demographic and lifestyle factors. RESULTS: Blood mercury was detected in 93% of children and 99% of adults, with geometric means (GMs) of 0.86 and 1.65 µg/L, respectively. The 60-65-year olds had the highest GM (2.34 µg/L). Regression indicated that tHg was 40% higher in boys compared to girls. Eating fish ≥ 3 times/week (compared to ≤once/week) was associated with 2.7 and 1.7 times higher tHg in children and adults, respectively. Shellfish consumption was also associated with higher tHg. High daily tap water consumption (≥2 L for children, ≥3 L for adults) was associated with lower tHg. In adults, smoking and milk consumption were associated with higher tHg. SIGNIFICANCE: Fish and shellfish consumption is a strong determinant of New Zealanders blood tHg levels, with water and milk consumption possibly acting as modulating factors.

An empirical test of the biodiversity hypothesis: Exposure to plant diversity is associated with a reduced risk of childhood acute lymphoblastic leukemia.

The biodiversity hypothesis posits that declining biodiversity may be responsible, at least in part, for the global increase in immune diseases. However, few studies have been able to demonstrate a link between exposure to biodiversity and specific health outcomes. We test whether exposure to plant diversity protects against childhood acute lymphoblastic leukemia (ALL) by promoting immune maturation. Our sample consisted of all children born in New Zealand from 1998 to 2013 (n = 899,126; 264 ALL cases), which we followed from birth to age five. We calculated plant-diversity metrics using the Global Biodiversity Information Facility, which contains over two million geocoded plant records in New Zealand. Consistent with previous research, children who had always lived in an urban area, or who had an older mother, were at greater risk for ALL, whereas children with older siblings were at lower risk. In addition, we found that plant-diversity metrics based on the maximum number of plant genera a child was exposed to during the first two years of life were protective of ALL. Specifically, exposure to the highest tertile of plant diversity was associated with a reduction in ALL risk of 35% (95% CI: 11%-53%). Exposure to plant diversity, and associated microbial communities, may be a viable public-health intervention to reduce the risk of ALL and possibly other immune diseases.

Occupational exposure to organic dust and risk of lymphoma subtypes in the EPILYMPH case-control study.

Objectives This study aimed to estimate the risk of lymphoma and its major subtypes in relation to occupational exposure to specific organic dusts. Methods We explored the association in 1853 cases and 1997 controls who participated in the EpiLymph case-control study, conducted in six European countries in 1998-2004. Based on expert assessment of lifetime occupational exposures, we calculated the risk of the major lymphoma subtypes associated with exposure to six specific organic dusts, namely, flour, hardwood, softwood, natural textile, synthetic textile, and leather, and two generic (any types) groups: wood and textile dusts. Risk was predicted with unconditional regression modeling, adjusted by age, gender, study center, and education. Results We observed a 2.1-fold increase in risk of follicular lymphoma associated with ever exposure to leather dust [95% confidence interval (CI) 1.01-4.20]. After excluding subjects who ever worked in a farm or had ever been exposed to solvents, risk of B-cell lymphoma was elevated in relation to ever exposure to leather dust [odd ratio (OR) 2.2, 95% CI 1.00-4.78], but it was not supported by increasing trends with the exposure metrics. Risk of Hodgkin lymphoma was elevated (OR 2.0, 95% CI 0.95-4.30) for exposure to textile dust, with consistent upward trends by cumulative exposure and three independent exposure metrics combined (P=0.023, and P=0.0068, respectively). Conclusions Future, larger studies might provide further insights into the nature of the association we observed between exposure to textile dust and risk of Hodgkin lymphoma.

Lung cancer risk in painters: results from the SYNERGY pooled case-control study consortium.

OBJECTIVES: We evaluated the risk of lung cancer associated with ever working as a painter, duration of employment and type of painter by histological subtype as well as joint effects with smoking, within the SYNERGY project. METHODS: Data were pooled from 16 participating case-control studies conducted internationally. Detailed individual occupational and smoking histories were available for 19 369 lung cancer cases (684 ever employed as painters) and 23 674 age-matched and sex-matched controls (532 painters). Multivariable unconditional logistic regression models were adjusted for age, sex, centre, cigarette pack-years, time-since-smoking cessation and lifetime work in other jobs that entailed exposure to lung carcinogens. RESULTS: Ever having worked as a painter was associated with an increased risk of lung cancer in men (OR 1.30; 95% CI 1.13 to 1.50). The association was strongest for construction and repair painters and the risk was elevated for all histological subtypes, although more evident for small cell and squamous cell lung cancer than for adenocarcinoma and large cell carcinoma. There was evidence of interaction on the additive scale between smoking and employment as a painter (relative excess risk due to interaction >0). CONCLUSIONS: Our results by type/industry of painter may aid future identification of causative agents or exposure scenarios to develop evidence-based practices for reducing harmful exposures in painters.

The carcinogenicity of pesticides used in New Zealand.

AIM: To estimate the number and weight of pesticides used in New Zealand agriculture that are classified as known or suspected human carcinogens. METHODS: The yearly usage of active ingredients was extracted from the most recent (2005) report on pesticide use. For each active ingredient, the carcinogenicity classification of three regulatory agencies (New Zealand Environmental Protection Authority [EPA NZ], US Environmental Protection Agency, European Chemicals Agency) was extracted. The International Agency for Research on Cancer (IARC) Monograph Programme's classifications were also considered. Total tonnes of active ingredients were calculated according to each classification. RESULTS: None of the pesticides are classified as known human carcinogens. In total, 56 active ingredients are listed as suspected carcinogens by at least one of the four agencies, including 16 high-use ingredients, representing up to 51% of the total yearly quantity. Agency-specific estimates ranged between 4-26% (148-872 tonnes) with the EPA NZ classification yielding the lowest estimate. The suspected carcinogen weight was highest for fungicides (estimates based on the three regulatory agencies ranged between 72-540 tonnes), followed by herbicides (60-200 tonnes) and insecticides (16 tonnes). CONCLUSIONS: New Zealand's use of pesticides that are suspected carcinogens is high. Efforts to increase awareness and reduce exposure need to be considered.

The Prevalence of Cardiovascular Risk Factors in Different Occupational Groups in New Zealand.

OBJECTIVES: Although cardiovascular disease (CVD) risk has been shown to differ between occupations, few studies have specifically evaluated the distribution of known CVD risk factors across occupational groups. This study assessed CVD risk factors in a range of occupational groups in New Zealand, stratified by sex and ethnicity. METHODS: Two probability-based sample surveys of the general New Zealand adult population (2004-2006; n = 3003) and of the indigenous people of New Zealand (Maori; 2009-2010; n = 2107), for which occupational histories and lifestyle factors were collected, were linked with routinely collected health data. Smoking, body mass index, deprivation, diabetes, high blood pressure, and high cholesterol were dichotomized and compared between occupational groups using age-adjusted logistic regression. RESULTS: The prevalence of all known CVD risk factors was greater in the Maori survey than the general population survey, and in males compared with females. In general for men and women in both surveys 'Plant and machine operators and assemblers' and 'Elementary workers' were more likely to experience traditional CVD risk factors, while 'Professionals' were less likely to experience these risk factors. 'Clerks' were more likely to have high blood pressure and male 'Agricultural and fishery workers' in the general survey were less likely to have high cholesterol, but this was not observed in the Maori survey. Male Maori 'Trades workers' were less likely to have high cholesterol and were less obese, while for the general population survey, this was not observed. CONCLUSIONS: This study showed differences in the distribution of known CVD risk factors across occupational groups, as well as between ethnic groups and males and females.

Clinical presentation of young people (10-24 years old) with brain tumors: results from the international MOBI-Kids study.

INTRODUCTION: We used data from MOBI-Kids, a 14-country international collaborative case-control study of brain tumors (BTs), to study clinical characteristics of the tumors in older children (10 years or older), adolescents and young adults (up to the age of 24). METHODS: Information from clinical records was obtained for 899 BT cases, including signs and symptoms, symptom onset, diagnosis date, tumor type and location. RESULTS: Overall, 64% of all tumors were low-grade, 76% were neuroepithelial tumors and 62% gliomas. There were more males than females among neuroepithelial and embryonal tumor cases, but more females with meningeal tumors. The most frequent locations were cerebellum (22%) and frontal (16%) lobe. The most frequent symptom was headaches (60%), overall, as well as for gliomas, embryonal and 'non-neuroepithelial' tumors; it was convulsions/seizures for neuroepithelial tumors other than glioma, and visual signs and symptoms for meningiomas. A cluster analysis showed that headaches and nausea/vomiting was the only combination of symptoms that exceeded a cutoff of 50%, with a joint occurrence of 67%. Overall, the median time from first symptom to diagnosis was 1.42 months (IQR 0.53-4.80); it exceeded 1 year in 12% of cases, though no particular symptom was associated with exceptionally long or short delays. CONCLUSIONS: This is the largest clinical epidemiology study of BT in young people conducted so far. Many signs and symptoms were identified, dominated by headaches and nausea/vomiting. Diagnosis was generally rapid but in 12% diagnostic delay exceeded 1 year with none of the symptoms been associated with a distinctly long time until diagnosis.

Exposure to Medical Radiation during Fetal Life, Childhood and Adolescence and Risk of Brain Tumor in Young Age: Results from The MOBI-Kids Case-Control Study.

BACKGROUND: We explored the association between ionizing radiation (IR) from pre-natal and post-natal radio-diagnostic procedures and brain cancer risk within the MOBI-kids study. METHODS: MOBI-kids is an international (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, New Zealand, Spain, The Netherlands) case-control study including 899 brain tumor (645 neuroepithelial) cases aged 10-24 years and 1,910 sex-, age-, country-matched controls. Medical radiological history was collected through personal interview. We estimated brain IR dose for each procedure, building a look-up table by age and time period. Lifetime cumulative doses were calculated using 2 and 5 years lags from the diagnostic date. Risk was estimated using conditional logistic regression. Neurological, psychological and genetic conditions were evaluated as potential confounders. The main analyses focused on neuroepithelial tumors. RESULTS: Overall, doses were very low, with a skewed distribution (median 0.02 mGy, maximum 217 mGy). ORs for post-natal exposure were generally below 1. ORs were increased in the highest dose categories both for post and pre-natal exposures: 1.63 (95% CI 0.44-6.00) and 1.55 (0.57-4.23), respectively, based on very small numbers of cases. The change in risk estimates after adjustment for medical conditions was modest. CONCLUSIONS: There was little evidence for an association between IR from radio-diagnostic procedures and brain tumor risk in children and adolescents. Though doses were very low, our results suggest a higher risk for pre-natal and early life exposure, in line with current evidence.

Welding fumes and lung cancer: a meta-analysis of case-control and cohort studies.

BACKGROUND: An estimated 110 million workers are exposed to welding fumes worldwide. Welding fumes are classified by the International Agency for Research on Cancer as carcinogenic to humans (group 1), based on sufficient evidence of lung cancer from epidemiological studies. OBJECTIVE: To conduct a meta-analysis of case-control and cohort studies on welding or exposure to welding fumes and risk of lung cancer, accounting for confounding by exposure to asbestos and tobacco smoking. METHODS: The literature was searched comprehensively in PubMed, reference lists of relevant publications and additional databases. Overlapping populations were removed. Meta-relative risks (mRRs) were calculated using random effects models. Publication bias was assessed using funnel plot, Eggers's test and Begg's test. RESULTS: Forty-five studies met the inclusion criteria (20 case-control, 25 cohort/nested case-control), which reduced to 37 when overlapping study populations were removed. For 'ever' compared with 'never' being a welder or exposed to welding fumes, mRRs and 95% CIs were 1.29 (1.20 to 1.39; I2=26.4%; 22 studies) for cohort studies, 1.87 (1.53 to 2.29; I2=44.1%; 15 studies) for case-control studies and 1.17 (1.04 to 1.38; I2=41.2%) for 8 case-control studies that adjusted for smoking and asbestos exposure. The mRRs were 1.32 (95% CI 1.20 to 1.45; I2=6.3%; 15 studies) among 'shipyard welders', 1.44 (95% CI 1.07 to 1.95; I2=35.8%; 3 studies) for 'mild steel welders' and 1.38 (95% CI 0.89 to 2.13; I2=68.1%; 5 studies) among 'stainless steel welders'. Increased risks persisted regardless of time period, geographic location, study design, occupational setting, exposure assessment method and histological subtype. CONCLUSIONS: These results support the conclusion that exposure to welding fumes increases the risk of lung cancer, regardless of the type of steel welded, the welding method (arc vs gas welding) and independent of exposure to asbestos or tobacco smoking.

Occupation and motor neuron disease: a New Zealand case-control study.

OBJECTIVES: To assess associations between occupation and motor neuron disease (MND). METHODS: We conducted a population-based case-control study with cases (n=321) recruited through the New Zealand Motor Neurone Disease Association and hospital discharge data. Controls (n=605) were recruited from the Electoral Roll. Information on personal and demographic details, lifestyle factors and a full occupational history was collected using questionnaires and interviews. Associations with ever/never employed and employment duration were estimated using logistic regression stratified by sex and adjusted for age, ethnicity, socioeconomic deprivation, education and smoking. RESULTS: Elevated risks were observed for field crop and vegetable growers (OR 2.93, 95% CI 1.10 to 7.77); fruit growers (OR 2.03, 95% CI 1.09 to 3.78); gardeners and nursery growers (OR 1.96, 95% CI 1.01 to 3.82); crop and livestock producers (OR 3.61, 95% CI 1.44 to 9.02); fishery workers, hunters and trappers (OR 5.62, 95% CI 1.27 to 24.97); builders (OR 2.90, 95% CI 1.41 to 5.96); electricians (OR 3.61, 95% CI 1.34 to 9.74); caregivers (OR 2.65, 95% CI 1.04 to 6.79); forecourt attendants (OR 8.31, 95% CI 1.79 to 38.54); plant and machine operators and assemblers (OR 1.42, 95% CI 1.01 to 2.01); telecommunications technicians (OR 4.2, 95% CI 1.20 to 14.64); and draughting technicians (OR 3.02, 95% CI 1.07 to 8.53). Industries with increased risks were agriculture (particularly horticulture and fruit growing), construction, non-residential care services, motor vehicle retailing, and sport and recreation. Positive associations between employment duration and MND were shown for the occupations fruit growers, gardeners and nursery growers, and crop and livestock producers, and for the horticulture and fruit growing industry. CONCLUSIONS: This study suggests associations between MND and occupations in agriculture and several other occupations.

Inequities in exposure to occupational risk factors between Maori and non-Maori workers in Aotearoa New Zealand.

BACKGROUND: Health inequities between indigenous and non-indigenous people are well documented. However, the contribution of differential exposure to risk factors in the occupational environment remains unclear. This study assessed differences in the prevalence of self-reported exposure to disease risk factors, including dust and chemicals, physical factors and organisational factors, between Maori and non-Maori workers in New Zealand. METHODS: Potential participants were sampled from the New Zealand electoral rolls and invited to take part in a telephone interview, which included questions about current workplace exposures. Logistic regression, accounting for differences in age, socioeconomic status and occupational distribution between Maori and non-Maori, was used to assess differences in exposures. RESULTS: In total, 2344 Maori and 2710 non-Maori participants were included in the analyses. Maori had greater exposure to occupational risk factors than non-Maori. For dust and chemical exposures, the main differences related to Maori working in occupations where these exposures are more common. However, even within the same job, Maori were more likely to be exposed to physical factors such as heavy lifting and loud noise, and organisational factors such as carrying out repetitive tasks and working to tight deadlines compared with non-Maori. CONCLUSIONS: This is one of the first studies internationally to compare occupational risk factors between indigenous and non-indigenous people. These findings suggest that the contribution of the occupational environment to health inequities between Maori and non-Maori has been underestimated and that work tasks may be unequally distributed according to ethnicity.