Spare non-occupational HIV post-exposure prophylaxis by active contacting and testing of the source person.

OBJECTIVE: HIV-1 post-exposure prophylaxis (PEP) is frequently prescribed after exposure to source persons with an undetermined HIV serostatus. To reduce unnecessary use of PEP, we implemented a policy including active contacting of source persons and the availability of free, anonymous HIV testing ('PEP policy'). METHODS: All consultations for potential non-occupational HIV exposures i.e. outside the medical environment) were prospectively recorded. The impact of the PEP policy on PEP prescription and costs was analysed and modelled. RESULTS: Among 146 putative exposures, 47 involved a source person already known to be HIV positive and 23 had no indication for PEP. The remaining 76 exposures involved a source person of unknown HIV serostatus. Of 33 (43.4%) exposures for which the source person could be contacted and tested, PEP was avoided in 24 (72.7%), initiated and discontinued in seven (21.2%), and prescribed and completed in two (6.1%). In contrast, of 43 (56.6%) exposures for which the source person could not be tested, PEP was prescribed in 35 (81.4%), P < 0.001. Upon modelling, the PEP policy allowed a 31% reduction of cost for management of exposures to source persons of unknown HIV serostatus. The policy was cost-saving for HIV prevalence of up to 70% in the source population. The availability of all the source persons for testing would have reduced cost by 64%. CONCLUSION: In the management of non-occupational HIV exposures, active contacting and free, anonymous testing of source persons proved feasible. This policy resulted in a decrease in prescription of PEP, proved to be cost-saving, and presumably helped to avoid unnecessary toxicity and psychological stress.

Exploratory Study on Occupational Health Exposure to Chemical Agents, in a Public Hospital in Valencia, Venezuela. Preliminar Assessment

Descriptive study that identified chemical agents (AQ) use and training on risk management and waste disposal techniques in a public Hospital in Valencia. A questionnaire was answered by 48 workers. Information obtained was: personal data, occupational history, AQ used; knowledge of risk management and waste disposal. There were 16 occupations from 12 “High Risk” areas. “Adult emergency” was the one with more workers (11 individuals), followed by “sterilization” and “clinical laboratory” (7 each) and oncology (5). The remained areas had less than 8.3% workers. The most used anesthetic agents were: Halothane, Enfluorane and Isofluorane 4.17% each and main antineoplastics used were: Doxorubicin 16.67% and Paclitaxel, 5-Fluoracil and Etoposide, 8.33% each. The most mentioned substances were: alcohol (70.8%) and Chlorine (64.6%). None of the answers regarding knowledge of AQ’ risk management and waste disposal was satisfactory. Statistical associations between training and several variables such as age, time in their job and being or not a professional, resulted non-significant. The correlation between training and the knowledge of AQ’s management was significant (p < 0.001). Participants showed that their knowledge about chemical occupational risk factors they are exposed to is still insufficient. Therefore, this theme should be included in graduate course curricula. These results provide important data and will serve as a pilot research for the follow up Phase II study that will include clinical aspects and environmental and biological monitoring.

Movies as a source of non-occupational noise exposure

This paper examines the noise levels of movies and whether or not movie theater sound levels may be hazardous to audience members.

In vivo CYP2E1 phenotyping as a new potential biomarker of occupational and experimental exposure to benzene

Assessing CYP2E1 phenotype in vivo may be important to predict individual susceptibility to those chemicals, including benzene, which are metabolically activated by this isoenzyme. Chlorzoxazone (CHZ), a specific CYP2E1 substrate, is readily hydroxylated to 6-OH-chlorzoxazone (6-OH-CHZ) by liver CYP2E1 and the metabolic ratio 6-OH-CHZ/CHZ in serum (MR) is a specific and sensitive biomarker of CYP2E1 activity in vivo in humans. We used this MR as a potential biomarker of effect in benzene-treated rats and, also, in humans occupationally exposed to low levels of benzene. Male Sprague-Dawley rats (375-400 g b.w.) were treated i.p. for 3 days with either a 0.5 ml solution of benzene (5 mmol/kg b.w.) in corn oil, or 0.5 ml corn oil alone. Twenty-four hours after the last injection, a polyethylene glycol (PEG) solution of CHZ (20 mg/kg b.w.) was injected i.p. in both treated and control animals. After 2, 5.10,15, 20,30,45, 60, 90, 120, 180, and 240 min from injection, 0.2 ml blood was taken from the tip tail and stored at -20 degrees C until analysis. A modified reverse phase HPLC method using a 5 mu m Ultrasphere C18 column equipped with a direct-connection ODS guard column, was used to measure CHZ and its metabolite 6-OH-CHZ in serum. No statistically significant difference in the MR was observed, at any sampling time, between benzene-treated and control rats. The concentration-versus-time area under the curve (AUC), however, was lower (p < 0.05, Mann-Whitney test), whereas the systemic clearance was higher (p < 0.05) in treated than in control rats. Eleven petrochemical workers occupationally exposed to low levels of airborne benzene (mean +/- SD, 25.0 +/- 24.4 mu g/m(3)) and 13 non-exposed controls from the same factory (mean +/- SD, 6.7 +/- 4.0 mu g/m(3)) signed an informed consent form and were administered 500 mg CHZ p.o. Two hours later a venous blood sample was taken for CHZ and 6-OH-CHZ measurements. Despite exposed subjects showed significantly higher levels of t,t-MA and S-PMA, two biomarkers of exposure to benzene, than non-exposed workers, no difference in the MR mean values +/- SD was found between exposed (0.59 +/- 0.29) and non-exposed (0.57 +/- 0.23) subjects. So, benzene was found to modify CHZ disposition, but not CYP2E1 phenotype in benzene-treated rats, nor in workers exposed to benzene, probably due to the levels of exposure being too low. (C) 2009 Elsevier B.V. All rights reserved.

Association between interleukin-6 polymorphism in the-174 G/C region and hearing loss in the elderly with a history of occupational noise exposure

Introduction: The biological processes involved in noise-induced hearing loss (NIHL) are still unclear. The involvement of inflammation in this condition has been suggested.Objective: To investigate the association between interleukin - 6 (IL-6) polymorphism and susceptibility to NIHL.Methods: This was a cross-sectional study with a sample of 191 independent elderly individuals aged >60 years of age. Information on exposure to occupational noise was obtained by interviews. Audiological evaluation was performed using pure tone audiometry and genotyped through PCR by restriction fragment length polymorphism - PCR-RFLP. Data were analyzed using the chi-square test and the odds ratio (OR), with the significance level set at 5%.Results: Among elderly with hearing loss (78.0%), 18.8% had a history of exposure to occupational noise. There was a statistically significant association between the genotype frequencies of the IL-6 - 174 and NIHL. The elderly with the CC genotype were less likely to have hearing loss due to occupational noise exposure when compared to those carrying the GG genotype (OR = 0.0124; 95% CI 0.0023-0.0671; p<0.001).Conclusion: This study suggests there is an association of polymorphisms in the IL-6 gene at position - G174C with susceptibility to noise-induced hearing loss. (C) 2014 Associacao Brasileira de Otorrinolaringologia e Cirurgia Cervico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Exposure to the Asp f 1 allergen in nonindustrial occupational environments

Sick Building Syndrome is a prevalent problem with patient complaints similar to typical allergy symptoms. Unlike most household allergens, the Asp f 1 allergen is conceivably ubiquitous in the work environment. This project examined levels of the Asp f 1 allergen in office and non-industrial occupational environments, and studied the bioaerosol and dust reservoirs of Aspergillus fumigatus responsible for those levels. ^ Culturable bioaerosols of total mesophilic fungi were sampled with Andersen N6 impactors. Aggressive airborne and bulk dust samples were concurrently collected and assayed for Asp f 1. Bulk dusts were selectively cultured for A. fumigatus. Samples were collected during both wet and dry climatological conditions to examine the possibility of Asp f 1 increases due to fungal growth blooms. ^ Only very low levels of Asp f 1 were detected in relatively few samples. Analysis of wet versus dry period samples showed no differences in Asp f 1 levels, although A. fumigatus counts from dusts did fluctuate significantly with exterior moisture events as did indoor prevalence of total colony forming units. These results indicate that even in the presence of elevated fungal concentrations, levels of Asp f 1 are extremely low. These levels do not correlate with climatological moisture events, despite distinct fungal blooms in the days immediately following those events. Non-industrial office buildings devoid of indoor air quality issues did not demonstrate significant levels or occurrence of Asp f 1 contamination in the geographical region of this study. ^

The normal range of the leukocyte count: Implications for surveillance of occupational and environmental exposure and the practice of preventive medicine

Leukopenia, the leukocyte count, and prognosis of disease are interrelated; a systematic search of the literature was undertaken to ascertain the strength of the evidence. One hundred seventy-one studies were found from 1953 onward pertaining to the predictive capabilities of the leukocyte count. Of those studies, 42 met inclusion criteria. An estimated range of 2,200cells/μL to 7,000cells/μL was determined as that which indicates good prognosis in disease and indicates the least amount of risk to an individual overall. Tables of the evidence are included indicating the disparate populations examined and the possible degree of association. ^

A cohort study of occupational asbestos-exposure related neoplasms in Texas Gulf Coast area

A cohort study was conducted in Texas and Louisiana Gulf Coast area on individual workers who have been exposed to asbestos for 15 years or more. Most of these workers were employed in petrochemical industries. Of the 15,742 subjects initially selected for the cohort study, 3,258 had positive chest X-ray findings believed to be related to prolonged asbestos exposure. These subjects were further investigated. Their work out included detailed medical and occupational history, laboratory tests and spirometry. One thousand eight-hundred and three cases with positive chest X-ray findings whose data files were considered complete at the end of May 1986 were analyzed and their findings included in this report.^ The prevalence of lung cancer and cancer of the following sights: skin, stomach, oropharyngeal, pancreas and kidneys were significantly increased when compared to data from Connecticut Tumor Registry. The prevalence of other chronic conditions such as hypertension, emphysema, heart disease and peptic ulcer was also significantly high when compared to data for the U.S. and general population furnished by the National Center for Health Statistics (NCHS). In most instances the occurrence of cancer and the chronic ailment previously mentioned appeared to follow 15-25 years of exposure to asbestos. ^

Assessment of occupational exposures to organic chemicals in a plastics manufacturing facility

The objective of this dissertation was to design and implement strategies for assessment of exposures to organic chemicals used in the production of a styrene-butadiene polymer at the Texas Plastics Company (TPC). Linear statistical retrospective exposure models, univariate and multivariate, were developed based on the validation of historical industrial hygiene monitoring data collected by industrial hygienists at TPC, and additional current industrial hygiene monitoring data collected for the purposes of this study. The current monitoring data served several purposes. First, it provided information on current exposure data, in the form of unbiased estimates of mean exposure to organic chemicals for each job title included. Second, it provided information on homogeneity of exposure within each job title, through the use of a carefully designed sampling scheme which addressed variability of exposure both between and within job titles. Third, it permitted the investigation of how well current exposure data can serve as an evaluation tool for retrospective exposure estimation. Finally, this dissertation investigated the simultaneous evaluation of exposure to several chemicals, as well as the use of values below detection limits in a multivariate linear statistical model of exposures. ^

Genetic susceptibility, cigarette smoking, and wood dust exposure in lung cancer: Case control analyses

This case control study was conducted to assess the association between lung cancer risk, mutagen sensitivity (a marker of cancer susceptibility), and a putative lung carcinogen, wood dust exposure. There were 165 cases (98 African-Americans, 67 Mexican-Americans) with newly diagnosed, previously untreated lung cancer, and 239 controls, frequency-matched on age, sex, and ethnicity.^ Mutagen sensitivity ($\ge$1 break/cell) was associated with a statistically significant elevated risk for lung cancer (odds ratio (OR) = 4.1, 95% confidence limits (CL) = 2.3,7.2). Wood dust exposure was also a significant predictor of risk (OR = 2.8, 95% CL = 1.2,6.6) after controlling for smoking and mutagen sensitivity. When stratified by ethnicity, wood dust exposure was a significant risk factor for African-Americans (OR = 4.0, 95% CL = 1.4,11.5), but not for Mexican-Americans (OR = 1.5, 95% CL = 0.3,7.1). Stratified analysis suggested a greater than multiplicative interaction between wood dust exposure and both mutagen sensitivity and smoking.^ The cases had significantly more breaks on chromosomes 4 and 5 than the controls did with ORs of 4.9 (95% CL = 2.0, 11.7) and 3.9 (95% CL = 1.6, 9.3), respectively. Breaks at 4p14, 4q27, 4q31, 5q21-22, 5q31, and 5q33 were significantly more common in lung cancer patients than in controls. Lung cancer risk had a dose-response relationship with breaks on chromosomes 4 and 5. Cigarette smoking had a strong interaction with breaks on chromosomes 2, 4, and 5.^ In a molecular cytogenetic study, using chromosome painting and G-banding, we showed that: (1) the proportion of chromosome 5 abnormalities surviving as chromosome-type aberrations remained significantly higher in cells of lung cancer cases (14%) than in controls (5%) (P $<$ 0.001). However, no significant differences were detected in chromosome 4 abnormalities between cases and controls; (2) the proportion of chromosome 5q13-22 abnormalities was 5.3% in the cases and 0.7% in the controls (P $<$ 0.001). 5q13-22 regions represented 40% of all abnormalities on chromosome 5 in the cases and only 14% in the controls.^ This study suggests that mutagen sensitivity, wood dust exposure, and cigarette smoking were independent risk factors for lung cancer, and the susceptibility of particular chromosome loci to mutagenic damage may be a genetic marker for specific types of lung cancer. ^

Economic/social impact of occupational noise exposure regulations : testimony presented at the OSHA hearings on the Economic Impact of Occupational Noise Exposure, Washington, D.C.

Mode of access: Internet.

Study of anticipated impact on DOE programs from proposed reduction to the external occupational radiation exposure limit.

Includes bibliographical references.