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Illness, injuries, and deaths from pesticide exposures in California 1949-1988.

Data on human acute illness/injury and death associated with pesticide exposure in California for the 40-yr period, beginning with 1949, were reviewed. Even though California has better data of this type than most government jurisdictions in the world, there are some shortcomings. In the early part of this period, nonoccupational data were scant because poison information centers were just being developed. Also in the early period, many occupational exposures were not recorded in state statistics although a good system to allow for such reporting was in place. California data currently available still do not take into account (i) persons who are exposed and become ill, but do not visit a physician or call a poison center, and (ii) most occupational exposures of the self-employed, U.S. military employees, U.S. government employees, maritime workers, and interstate railroad workers. In 1987, 268,092,595 kg of pesticides were sold and estimated as used in the state. Although the amount of pesticides used annually in California is estimated to have increased 4-fold in this 40-yr period, it is believed that the actual number of pesticide-related occupational illnesses/yr increased very little. Cholinesterase inhibitors and methyl bromide were most often involved in the more serious occupational systemic poisonings throughout the time period. Well-educated and trained farmers and other pesticide handlers as well as a strict regulatory system have contributed to keeping the number and the extent of pesticide exposure in check, considering the widespread use of pesticides, some of which are quite toxic and potentially hazardous if misused. In 1987, there were 1,507 cases of occupational illness identified, with 744 of these demonstrating systemic toxic symptoms. In 1987, approximately 17,000 human pesticide exposure incidents, almost all of which were nonoccupational, were handled by poison control centers. It is estimated that about 30 to 60% developed signs or symptoms. Occupational deaths for the past 10 yr have averaged about 1/yr. Suicides by use of pesticides are estimated at 15/yr, and nonsuicides, nonoccupational deaths are estimated at 5/yr. This paper does not address chronic effects such as cancer induction, developmental effects, or reproductive effects that may be suspected as being the result of pesticide exposure. Data presented in this report may be useful in estimating the number of poisonings that may occur in other geographic settings. Numerous variables that must be considered in making such estimates are discussed.

Agricultural Workers' Diseases↗

Occupational risk factors for multiple myeloma among Danish men.

A large population-based case-control study evaluated occupational exposures in 1,098 Danish males diagnosed with multiple myeloma from 1970 to 1984 and in 4,169 age- and gender-matched controls alive at the time of case-diagnosis. Industrial histories were obtained from the Supplementary Pension Fund which, since 1964, has recorded employments of adult Danes; occupation came from subjects' most recent tax records. Four industrial hygienists created a job-exposure matrix for 47 substances based on 15,000 unique industry/occupation combinations in subjects' histories. Risk of myeloma was significantly elevated among road and railroad workers, precision metalworkers, and workers in the transportation and communication industries. Risk increased significantly with duration of employment in: production of synthetic yarns, plastic packaging, and miscellaneous chemical compounds; fabricating structural metal and stationary tanks; body factories; electrical plants; and retail sale of paint and wallpaper. Risks of myeloma were elevated, though statistically nonsignificantly, in all categories of exposure to gasoline and engine exhausts. Risks rose with likelihood and duration of exposure to phthalates, and were statistically significant and nearly fivefold with probable exposure to vinyl chloride for five or more years. After adjusting for multiple exposures and disregarding exposures within 10 years of diagnosis (or selection as a control), probable exposure to vinyl chloride was associated with increased risk of myeloma, which rose to fivefold with longer exposure. Associations with gasoline, engine exhausts, and phthalates persisted, but were inconsistent with duration and probability of exposure. Previously reported associations with agriculture were not confirmed by these data.

Age Factors↗

Modified crossover and guidewire loop technique for double-balloon angioplasty of the aortic bifurcation.

A modified form of crossover railroad technique is described for iliac and aortic bifurcation obstructions in which the iliac occlusion is crossed from the opposite side by a guidewire which is brought out through the ipsilateral puncture site. After forming a loop in the abdominal aorta, dilatation with two balloons is performed. This procedure was successfully performed in 2 patients having iliac artery occlusions and aortic bifurcation obstruction.

Angioplasty, Balloon↗

Sensitivity of Roberts syndrome cells to gamma radiation, mitomycin C, and protein synthesis inhibitors.

Roberts syndrome (RS) is a rare autosomal recessive disorder characterized by pre- and postnatal growth retardation, limb reduction abnormalities, and craniofacial anomalies. Mitotic chromosomes from RS individuals display repulsion of heterochromatin regions or centromere splitting, leading to a railroad-track appearance of mitotic chromosomes. Abnormalities in metaphase duration, anaphase progression, nuclear morphology, and increased frequency of micronucleation have been reported in RS cells. Cells from RS heterozygotes are normal in these respects, and in vitro complementation of the defects in somatic cell hybrids has been reported. Therefore, in preparation for the isolation of cDNAs that complement the RS defect, we investigated various drug treatments to identify an agent that specifically involves the growth of RS cells. Based on the cytogenetic and cell biologic findings, we chose agents that increase micronucleation or inhibit protein synthesis. We found that RS cells are hypersensitive to gamma radiation, mitomycin C, G418 and hygromycin B, but not to colcemid or streptonigrin when compared to normal cells. DNA content and cell viability analysis confirmed that the sensitivity to gamma irradiation was primarily due to increased cell death.

Abnormalities, Multiple↗

A mathematical model for the European spread of influenza.

Following a study modelling the geographical spread of influenza in France, on the basis of population movements through the use of railroad data, we applied the same methodology on a European scale. We simulated an epidemic within a network of 9 European cities (Amsterdam, Berlin, Budapest, Copenhagen, London, Madrid, Milano, Paris, Stockholm), only taking into account regular between-cities air transport. Transportation data were obtained from the International Civil Aviation Organization (1991). The theoretical results show that the time lag for action is probably short (less than one month) after the first detection of an epidemic focus.

Aviation↗

Airway management in a patient with a cleft palate after pharyngoplasty: a case report.

PURPOSE: To describe a practical method of aiding nasotracheal intubation in a cleft palate patient with previous pharyngoplasty using a suction catheter under tactile guidance. Problems of airway management in these patients are also discussed. CLINICAL FEATURES: A 26-yr-old woman presented for elective Le Fort maxillary osteotomy. She had a history of cleft lip and palate and subsequent palatoplasty and pharyngeal flap. She had no symptoms of upper airway obstruction or obstructive sleep apnea. Preoperative examination revealed a hypernasal voice and patent nasal passages. Anesthesia was induced and the patient paralyzed. An attempt to pass a 6.5-mm cuffed endotracheal tube through the right nostril met with resistance. A suction catheter was introduced into the nostril, while a finger was positioned over the flap and the velopharyngeal port, until its tip rested against the flap, the catheter coiled and a small loop could be palpated past the patent velopharyngeal port. The catheter was then hooked into the oropharynx. The endotracheal tube was "railroaded" over it and advanced into the glottis. There was minimal bleeding and no desaturation during the procedure. CONCLUSION: Preoperative determination of the type of pharyngoplasty is essential to understand the anatomy of the patent velopharyngeal port. A history of pharyngeal flap infection, hyponasal voice or upper airway obstruction suggests possible port stenosis. We describe a tactile guided technique that is useful and practical. Use of a flexible suction catheter of small external diameter minimizes the potential for trauma, bleeding and creation of false passages.

Adult↗

Adverse effects on Alfeios River Basin and an integrated management framework based on sustainability.

The Alfeios River, the longest and highest flow-rate river in Peloponnisos, constitutes an important water resource and ecosystem in Greece. In the present study, human activities in the Alfeios River Basin are described, and their impacts on water quality and the ecosystem are analyzed; effects resulting from interventions on river geomorphology between Flokas Dam and the river delta are determined. These actions have caused significant adverse impacts on the infrastructure (the dam, railroad, and road bridges), the level of aquifer water table and area water uses, and the aquatic and riparian ecosystem. A general integrated management strategy is formulated and a master management plan is proposed for resolving management problems in river basins. The plan considers local conditions and national requirements and complies with the European Communities legislation; it would help prevent further basin deterioration, improve water quality, and protect water resources and ecosystems in the area in accordance to sustainable development. The Alfeios River Basin serves as a case study in the development of the plan.

Agriculture↗

Nd-YAG laser core-through urethrotomy in obliterative posttraumatic urethral strictures in children.

This study analysed the feasibility and effectiveness of Nd-YAG laser core-through urethrotomy in the management of obliterative posttraumatic urethral strictures in children. Between May 1997 and April 2000, 61 patients underwent core-through urethrotomy in posttraumatic urethral strictures, ten of whom were children (ages 5-15 years). Three patients had had previous railroading procedures, two attempted core-through urethrotomy, and two underwent end-to-end urethroplasties. Patients were on suprapubic cystostomy for a mean period of 12 months with mean stricture length of 2 cm. Nd-YAG laser core-through urethrotomy was carried out using 600- micro m bare-contact fibre as a day care procedure. There were no intraoperative or postoperative complications. Micturating cystourethrography was performed 6 weeks following urethral catheter removal. Urethroscopy and uroflowmetry were carried out after 3 months. Mean follow-up was 24 months.Nd-YAG laser core-through urethrotomy was seen to be successful in all patients without any complications. All patients are voiding without obstructive symptoms. Four required optical urethrotomy/endoscopic dilatation at least twice. Nd-YAG laser core-through urethrotomy is a safe and effective procedure for the management of obliterative posttraumatic urethral strictures in children

Adolescent↗

What is new in diesel.

We review information from the past 5 years on changes in diesel exhaust (DE) emissions and developments in the study of DE toxicity. New DE technologies have changed the composition of DE considerably, reducing emissions of many of the components of health concern. The increasing similarity of modern diesel and compressed natural-gas engine emissions needs to be reflected in any regulatory analysis. Even for historical DE emissions, considerable study of DE exposure in animals or humans has not produced data useful for risk assessment. DE inhalation exposure in most species (hamsters, guinea pigs, mice) does not produce lung tumors. Inhalation studies of DE in rats found lung tumors only with lung overload, and tumors also occurred when inert dusts were inhaled at overload concentrations. The animal data are reassuring and show that DE is not a concern at ambient exposure levels. Re-analyses of occupational epidemiology have been shown to have serious shortcomings that do not allow the derivation of a quantitative cancer risk. Studies of railroad workers found no dose response; rather cancer risk appeared to decrease for individuals with greater DE exposure. Studies of truck drivers also suffer from serious flaws because of misconceptions about the year that diesel was introduced, lack of an adequate latency period, and the realization that drivers exhibited increased lung cancer risk even prior to the diesel era. Recent industrial hygiene studies of drivers show that DE was not likely to be a primary source of particles or polycyclic aromatic hydrocarbons. Further, there is no dose response across occupations. In fact, the occupation (underground miners) with the highest exposure to DE does not exhibit increased cancer risks. This new information seriously weakens earlier risk characterizations of DE by various regulatory groups. New research and better exposure measurements are needed before a reliable risk assessment of DE can be produced.

Air Pollutants↗

Phosphorus trichloride toxicity. Preliminary report.

A railroad accident in Somerville, Massachusetts, led to spillage of phosphorus trichloride liquid. Attempted clean-up with water led to the liberation of phosphorus trichloride, phosphoric acid, hydrochloric acid, and phosphorus oxides. Seventeen people exposed to this mixture were studied. Patients experienced eye irritation, lacrimination, nausea, vomiting, and dyspnea. Six patients had transient elevation of lactic dehydrogenase. Although all patients had normal chest roentgenographic findings, pulmonary function tests showed statistically significant decreases in vital capacity (p = 0.02), maximal breathing capacity (p = 0.02), forced expiratory volume in one second (p = 0.02), and maximal expiratory flow rate at 25 percent of vital capacity (p = 0.05) in those closest to the accident site. Further, patients exposed for less than one and a half hours had significantly greater maximal expiratory flow rates at 25 percent of vital capacity when compared with patients who had been exposed longer (p = 0.02). In seven patients, repeated pulmonary function tests one month later showed improvement, suggesting strongly that the acute effects may have been due to phosphorus trichloride toxicity.

Accidents, Traffic↗

Ergonomic research in German travelling mail service. Part 1: ergonomic problems and research in railway mail vans.

Ergonomic problems in the travelling mail service are described, showing the necessity of ergonomic research work within the railway mail van, to obtain results suitable for evaluating the strain of travelling mail office clerks as well as for designing the system of a mail railroad car. The special methodological procedure of this type of ergonomic field research is discussed.

Journal Article↗

Forces applied to large hand wheels.

This is a report of a study conducted to establish the population isometric strength capabilities of subjects generating force using a hand wheel. Wheel force strength of 125 males and 125 females was measured using two different handgrip configurations: grasping the rim of the wheel and grasping the spoke. In addition, two separate procedures for generating and measuring strength were used: a 3 s average during a 6 s trial, and a ramp to maximum exertion level and then relax. The task simulated setting a handbrake on a typical railroad box car. Results indicated that grip characteristics and grip strength play an important role in isometric wheel force strength capabilities. The average tangential forces ranged from 393 to 614 N for males, and from 235 to 348 N for females, depending upon the grip configuration and the method used to measure strength. Standard whole-body strength measures for the legs, arms, torso and grip were also measured and demonstrated to be effective in predicting the wheel force strength capabilities of the subjects.

Journal Article↗

Biomechanics of fruits and vegetables.

The scope of fruit and vegetable biomechanics is reviewed. Sources of mechanical injury to produce in harvesting, processing, storage, packaging and transportation are briefly described. A survey of produce handling and transportation environments was conducted, whereby an envelope model encompassing composite spectra of trucks, railroad, marine and cargo aircraft is presented. The protective quality, i.e. strength of shipping containers is quantified in static and dynamic loading such as encountered in storage, handling and transportation. Mechanical response of fruits and vegetables in quasistatic and dynamic loading are formulated by a nonlinear rheological model, whereby a time and deformation dependent relaxation modulus is defined. A realistic link is established between the model and real fruits and vegetables by test procedures for determination of the parameters in the governing nonlinear equations. Based on the nonlinear relaxation modulus, mechanical damage of fruits and vegetables is quantified for static compression, transients and vibration loading as well as for combined static and dynamic loading, by equations of contact circle diameter, bruise depth and contact pressure. Distribution of loads over a maximal number of contact points per fruit is linked to geometrical patterns of produce packs. The application of Shock Damage Boundary techniques for produce-package testing is described along with a case study comparing the protective qualities of two types of apple packs. Produce damage quantification by direct fruit inspection in terms of a 'Bruise Index' is described, including a practical example, comparing the protective qualities of three types of apple packs in shipping tests. Indirect methods of mechanical injury evaluation, based on weight loss and CO2 emission differences between bruised and wholesome fruits are also briefly discussed.

Biomechanical Phenomena↗

An assessment of caloric intake as an indicator of physical activity.

Caloric intake has been suggested as a surrogate measure of physical activity, provided that energy balance is maintained. In this study we assessed caloric intake in relation to other measures of physical activity in a free-living population by a single 24-hr recall in white adult males, ages 22-79 years, examined in 1957-1960 as part of the U.S. Railroad Study. Intake was positively related to leisure time and occupational activity. Men with higher levels of caloric intake had lower exercise test heart rates indicating that they were probably more fit. Caloric intake was also significantly and inversely related to body mass index, the sum of the triceps and subscapular skinfold thickness measurements, blood pressure, and total serum cholesterol. These results suggest that caloric intake, even as measured in a 24-hr dietary recall, is an indicator of physical activity level. Therefore, caloric intake may be a useful indicator of physical activity in some population-based epidemiologic studies.

Adult↗

The etiology of problem drinking in the workplace.

American railroad workers (n = 5804) were surveyed to test whether occupational risk factors specified by Trice and Roman are related to problem drinking. Because sex and age covary strongly with problem drinking and these variables are also likely to covary with occupation, the effects of sex and age were partialled from the correlations in these analyses. Although correlations were without exception small (p less than 0.10) many were significant (p less than 0.05), lending support to the hypothesis that some characteristics of the work situation are likely to cause or to foster problem drinking at least to some degree. As with most correlational studies, it is impossible firmly to establish direction of causality, and the possibility remains that some of the results reported here reflect the gravitation of problem drinkers into jobs where they are less likely to be discovered, in danger, or dangerous.

Age Factors↗

Lateralization of object-shape information in semantic processing.

An experiment was conducted to examine whether perceptual information, specifically the shape of objects, is activated during semantic processing. Subjects judged whether a target word was related to a prime word. Prime-target pairs that were not associated, but whose referents had similar shapes (e.g. LADDER-RAILROAD) yielded longer "no" responses than unassociated prime-target pairs, suggesting that shape information had been activated. A visual-field manipulation showed that, in right-handed subjects, this effect was localized in the left hemisphere. This finding is consistent with behavioral, brain imaging, and lesion data, which suggest that object shape at the category level is represented in the left hemisphere.

Affect↗

The environmental history of Chatthin Wildlife Sanctuary, a protected area in Myanmar (Burma).

We reconstructed the history of Chatthin Wildlife Sanctuary (CWS) to understand how social and economic events, and policy changes affected the sanctuary's condition. We surveyed 25 villages surrounding CWS to evaluate past and present ecological conditions, compare the results with historical accounts and identify causal relationships. During the first half of the 20th century, the primary threat was the government's reduction of old growth forest to supply fuel wood for the British-built railway. The railroad opened the area to colonization, but the villagers' impact on timber and wildlife was low. From 1945 to 1988, villagers became the primary force of landscape degradation. The post-war windfall of firearms increased hunting pressure, and populations of large mammal started to decline. With the economic decline of the 1970s and 1980s, the community's demand for game and forest products intensified, and the large mammal fauna was reduced from eleven to four species. From 1988-2003, the forests surrounding the sanctuary were fragmented and degraded. The absence of large predators rendered the park safe for livestock, and the combined effects of grazing and removal of forest products seriously degraded habitat within CWS. Major threats to CWS during the past two decades have resulted from land use decisions in which government-planned economic enterprises caused encroachment by villagers. Stabilization and recovery of this sanctuary will require management compatible with human needs, including expanded buffer zones, better core area protection, community forestry projects, and probably relocation of villages within the park.

Animals↗

Trees as reservoirs for amphibole fibers in Libby, Montana.

Tree bark and core samples were collected from areas surrounding the asbestos-contaminated vermiculite mine in Libby, MT. These samples were collected to provide preliminary data in support of a proposed study to determine if trees can serve as reservoirs for amphibole fibers and to determine if there is a potential for exposure to those that harvest contaminated wood in the Libby mine area, specifically during firewood harvesting and commercial logging. Initially, three sets of samples were taken both within and directly outside of the EPA restricted area surrounding the mine site. Based on the results of the initial samples, a follow-up sampling program was conducted both in the town of Libby and directly outside the city limits. Gravimetric reduction of a tree core sample did not indicate the presence of amphibole fibers. However, transmission electron microscopy analysis of bark samples collected near the vermiculite mine yielded substantial amphibole fiber concentrations ranging from 41 million to 530 million fibers/g of bark. In addition, a bark sample collected approximately 7 miles west of the town next to a railroad line had concentrations of 19 million fibers/g. A conversion of these mass-based concentrations to areal concentrations (to reflect surface area contamination) revealed concentrations in excess of 100 million amphibole fibers/cm(2). These preliminary results suggest that trees in the Libby valley and along vermiculite shipping corridors can serve as reservoirs for amphibole fibers, and that a potential for exposure exists for those who harvest contaminated wood.

Asbestos, Amphibole↗