Health Effects of Airborne Exposures from Concentrated Animal Feeding Operations

Toxic gases, vapors, and particles are emitted from concentrated animal feeding operations (CAFOs) into the general environment. These include ammonia, hydrogen sulfide, carbon dioxide, malodorous vapors, and particles contaminated with a wide range of microorganisms. Little is known about the health risks of exposure to these agents for people living in the surrounding areas. Malodor is one of the predominant concerns, and there is evidence that psychophysiologic changes may occur as a result of exposure to malodorous compounds. There is a paucity of data regarding community adverse health effects related to low-level gas and particulate emissions. Most information comes from studies among workers in CAFO installations. Research over the last decades has shown that microbial exposures, especially endotoxin exposure, are related to deleterious respiratory health effects, of which cross-shift lung function decline and accelerated decline over time are the most pronounced effects. Studies in naïve subjects and workers have shown respiratory inflammatory responses related to the microbial load. This working group, which was part of the Conference on Environmental Health Impacts of Concentrated Animal Feeding Operations: Anticipating Hazards—Searching for Solutions, concluded that there is a great need to evaluate health effects from exposures to the toxic gases, vapors, and particles emitted into the general environment by CAFOs. Research should focus not only on nuisance and odors but also on potential health effects from microbial exposures, concentrating on susceptible subgroups, especially asthmatic children and the elderly, since these exposures have been shown to be related to respiratory health effects among workers in CAFOs

Ethnicity and incidence of Hodgkin lymphoma in Canadian population

<p>Abstract</p> <p>Background</p> <p>Research has shown that ethnicity is a significant predictor of Hodgkin lymphoma (HL). Variations in cancer incidence among ethnic groups in the same country can lead to important information in the search for etiological factors. Other risk factors important in the etiology of HL are medical history and exposure to pesticides. In this report we investigated the association between ethnicity and HL in the presence of medical history, and exposure to pesticides.</p> <p>Methods</p> <p>The data resulting from a matched population-based case-control study conducted in six provinces of Canada (Ontario, Quebec, Manitoba, Saskatchewan, Alberta, and British Columbia) was analyzed to determine whether or not there was any association between ethnicity and incidence of HL when adjusted for personal medical history and pesticide exposure. Information on ethnicity, personal medical history, and pesticide exposure was collected by questionnaires via mail on 316 men diagnosed with HL; and on 1506 controls. A conditional logistic regression was utilized and results were presented as odds ratios and 95% confidence intervals.</p> <p>Results</p> <p>In our study population, the distribution of ethnic groups was: 38.5% North American, 15% British, 8.4% Western European, 8.2% Eastern European, 1.7% Asian, 1.4% Scandinavian and 27% of other ethnic origin. Compared to North Americans (i) the risk of HL was greater among the Eastern European descendents (Odds Ratio (OR_adj): 1.82; 95% confidence interval (CI): 1.02, 3.25) and Western European (OR_adj: 1.62; 95% CI: 0.95–2.76) descent population (borderline significance at 5% level); and (ii) the risk of HL was lower in Asian descents. Diagnosis with measles (OR_adj: 0.72, 95% C.I.: 0.53–0.98) and/or positive history of allergy desensitization shots (OR_adj: 0.55, 95% C.I.: 0.30–0.99) were negatively associated with the incidence of HL, while diagnosis with acne (OR_adj: 2.12, 95% C.I.: 1.19–3.78), shingles (OR_adj: 2.41, 95% C.I.: 1.38–4.22) and positive family history of cancer (OR_adj: 1.93, 95% C.I.: 1.40–2.65) increased the risk of HL. Exposure to individual herbicide dichlorprop showed an increased risk of HL (OR_adj: 6.35, 95% C.I.: 1.56–25.92).</p> <p>Conclusion</p> <p>In Canada, compared to North Americans descendents, the risk of HL was significantly greater among the Eastern European and Western European descent population. Our results related to association between ethnicity and HL support the findings reported by other researchers. Our data showed that subjects who were diagnosed with measles or had allergy desensitization shots negatively associated with the incidence of HL; and other medical conditions, ever diagnosed with acne, and positive family history of cancer were positively associated with the incidence of HL.</p

Association of the TLR4 Asp299Gly polymorphism with lung function in relation to body mass index

<p>Abstract</p> <p>Background</p> <p>Previous studies have shown conflicting results for the association between TLR4 polymorphism (Asp299Gly) and lung function. We investigated the influence of TLR4 Asp299Gly, a polymorphism, on lung function in a community population.</p> <p>Methods</p> <p>In 2003, a cross-sectional survey was conducted to assess the respiratory health of residents living in and around the town of Humboldt, Saskatchewan, Canada. There were 2090 adults age 18-79 years who completed a questionnaire that included a medical and smoking history, as well as socio-economic and lifestyle variables. Genetic information and lung function test measurements were available on 1725 subjects (754 males and 971 females) of the 2090 respondents. These subjects were selected for further analysis to investigate the association between TLR4 Asp299Gly genotype and forced expiratory volume in the first second in liters (FEV₁), forced vital capacity in liters (FVC), FEV₁/FVC ratio, and forced expiratory flow rate in liters/second (FEF_25-75). Multivariable linear regression analysis was used to investigate associations.</p> <p>Results</p> <p><b>A</b>djusted mean values of FEV₁and FVC were significantly different between TLR4 wild type and TLR4 variant groups [Mean ± S.E.: (TLR4 wild type - FEV₁: 3.18 ± 0.02, FVC: 3.95 ± 0.03; TLR4 variant - FEV₁: 3.31 ± 0.06, FVC: 4.14 ± 0.07)]. Based on multivariable regression analysis, we observed that body mass index (BMI) was associated with decreased FEV₁/FVC ratio and FEF_25-75in TLR4 variant group but not in wild type group.</p> <p>Conclusion</p> <p>BMI may modify the associations of TLR4 Asp299Gly polymorphism with FEV₁/FVC ratio and FEF_25-75.</p

Percutaneous injuries among dental professionals in Washington State

BACKGROUND: Percutaneous exposure incidents facilitate transmission of bloodborne pathogens such as human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV). This study was conducted to identify the circumstances and equipment related to percutaneous injuries among dental professionals. METHODS: We used workers' compensation claims submitted to the Department of Labor and Industries State Fund during a 7-year period (1995 through 2001) in Washington State for this study. We used the statement submitted by the injured worker on the workers' compensation claim form to determine the circumstances surrounding the injury including the type of activity and device involved. RESULTS: Of a total of 4,695 accepted State Fund percutaneous injury claims by health care workers (HCWs), 924 (20%) were submitted by dental professionals. Out of 924 percutaneous injuries reported by dental professionals 894 (97%) were among dental health care workers in non-hospital settings, including dentists (66, 7%), dental hygienists (61, 18%) and dental assistants (667, 75%). The majority of those reporting were females (638, 71%). Most (781, 87%) of the injuries involved syringes, dental instruments (77, 9%), and suture needles (23%). A large proportion (90%) of injuries occurred in offices and clinics of dentists, while remainder occurred in offices of clinics and of doctors of medicine (9%), and a few in specialty outpatient facilities (1%). Of the 894 dental health care workers with percutaneous injuries, there was evidence of HBV in 6 persons, HCV in 30 persons, HIV in 3 persons and both HBV and HVC (n = 2) exposure. CONCLUSION: Out of hospital percutaneous injuries are a substantial risk to dental health professionals in Washington State. Improved work practices and safer devices are needed to address this risk

Clustering of cancer among families of cases with Hodgkin Lymphoma (HL), Multiple Myeloma (MM), Non-Hodgkin's Lymphoma (NHL), Soft Tissue Sarcoma (STS) and control subjects

<p>Abstract</p> <p>Background</p> <p>A positive family history of chronic diseases including cancer can be used as an index of genetic and shared environmental influences. The tumours studied have several putative risk factors in common including occupational exposure to certain pesticides and a positive family history of cancer.</p> <p>Methods</p> <p>We conducted population-based studies of Hodgkin lymphoma (HL), Multiple Myeloma (MM), non-Hodgkin's Lymphoma (NHL), and Soft Tissue Sarcoma (STS) among male incident case and control subjects in six Canadian provinces. The postal questionnaire was used to collect personal demographic data, a medical history, a lifetime occupational history, smoking pattern, and the information on family history of cancer. The family history of cancer was restricted to first degree relatives and included relationship to the index subjects and the types of tumours diagnosed among relatives. The information was collected on 1528 cases (HL (n = 316), MM (n = 342), NHL (n = 513), STS (n = 357)) and 1506 age ± 2 years and province of residence matched control subjects. Conditional logistic regression analyses adjusted for the matching variables were conducted.</p> <p>Results</p> <p>We found that most families were cancer free, and a minority included two or more affected relatives. HL [(OR_adj(95% CI) <b>1.79 (1.33, 2.42)]</b>, MM <b>(1.38(1.07, 1.78))</b>, NHL <b>(1.43 (1.15, 1.77)</b>), and STS cases <b>(1.30(1.00, 1.68)) </b>had higher incidence of cancer if any first degree relative was affected with cancer compared to control families. Constructing mutually exclusive categories combining "family history of cancer" (yes, no) and "pesticide exposure ≥10 hours per year" (yes, no) indicated that a positive family history was important for HL <b>(2.25(1.61, 3.15))</b>, and for the combination of the two exposures increased risk for MM <b>(1.69(1.14,2.51))</b>. Also, a positive family history of cancer both with <b>(1.72 (1.21, 2.45)) </b>and without pesticide exposure <b>(1.43(1.12, 1.83)) </b>increased risk of NHL.</p> <p>Conclusion</p> <p>HL, MM, NHL, and STS cases had higher incidence of cancer if any first degree relative affected with cancer compared to control families. A positive family history of cancer and/or shared environmental exposure to agricultural chemicals play an important role in the development of cancer.</p